Return to the home page...

Go Back   Moyer Marine Atomic 4 Community - Home of the Afourians > Discussion Topics > Troubleshooting

Reply
 
Thread Tools Display Modes
  #1   IP: 184.70.15.142
Old 07-31-2012, 02:35 AM
Jon K Jon K is offline
Frequent Contributor
 
Join Date: Jul 2012
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Request advice with stalling engine

Thanks in advance for your advice.

My 1985 Atomic 4 has developed some problems, it stalls after reaching 180 degrees and won't restart until it cools. It also has a history of performing fine under power, then stalling when brought to idle when returning to port.

History:

I bought a late 1970s Ranger 28 in 2006, the marine surveyor said it was sound and we began sailing the boat and updating the cabin.

Recently I have noticed that the wiring in this negative-ground system uses different colors of wire, spliced partway through each run to another color. With red, orange, white and yellow wires, the only color absent on the ground side is black. I've added a second cigarette lighter receptacle so the GPS and handheld spotlight can be run at the same time, not much else.

I read about the Atomic 4 and learned how to do a few things, including how to change the oil. It is a traditional, un-upgraded engine with a new heat exchanger - freshwater cooling and two pumps. It burns a little oil, perhaps a quarter-litre per season of 10-12 hours of use. I tend to run the engine near or at top RPM, using my ear to avoid over-throttling. After 5 seasons I have put about 70 hours on the engine.

At one point the engine was overheating, it turns out that the saltwater through-hull was clogged with seaweed. A coathanger was an easy tool to clear the clog. Now it runs at 180 degrees all the time.

Every season we make a long trip that begins with a 5-hour crossing of the Georgia Straight between the mainland and the Gulf Islands, here in the Vancouver, BC area.

In the fourth year, returning from one such trip, the engine stalled after a few hours, when brought to idle from 2-3 hours at full speed. We had slowed to make a passage between two islands, possible only at flat water. Luckily a passing motorboat offered us a tow through, and we decided to make port nearby to diagnose the problem. As it turned out, during the passage the problem had cleared and we were able to restart and continue home.

After a speedy 3.5 hour crossing under sail and 2/3 power, I idled the engine to drop sails and moor the boat. Engine died and would not restart. We took a tow in and ended the season.

Last year in Spring I took the boat for service, only to stall half-way after running for about an hour. A friend brought some methyl hydrate which we added to the fuel, and we blew through the line to attempt to clear any blockage - the ragged running of the engine suggested a fuel starvation problem.

After 30 minutes or so the engine restarted, and so I handed the boat over the boat yard manager who convinced me to install new fuel lines, a Rakor filter, and an electric fuel pump to pull the gas through it. Electronic ignition was added, as well as new plugs and wires.

After the service the engine seemed to run well, however issues soon developed:

1. The electric fuel pump wasn't working -- I rewired it myself by adding a new hot lead from the engine cutoff switch. Now it spurts gas at the carb whenever I test it.

2. The common ground for some house wiring is gone; I rewired the house water pump with a ground directly to the gear housing. The mast light stays on whenever the batteries are engaged.

I think the mechanic was a little clumsy, or changed the wiring while installing the fuel pump. These are not critical issues for me, I will rewire at some future time. Just more data points.

This season I have completed a recent journey with the following symptoms:

3. Fairly constant loss of coolant, needing 1/2 litre for 30 minutes engine time. First noted when engine overheated with steam in the exhaust. I thought at first it was oil burning, but the cloud was white and smelled like antifreeze not stinky like oil.

4. During the same hot-engine breakdown I pulled plugs 1 and 2. Both looked okay, but I saw no fuel in the cylinders while cranking. Maybe it just evaporates in the hot engine. No obvious issues in the cylinder or plugs.

5. At the same time I tested for spark -- good spark. Tested for fuel at the carb -- lots of gas.

The engine restarted after ccooling, but once again stalled and would not restart when we slowed down to begin mooring.

So I tested a few things:

6. Thermostat works fine in boiling water.

7. Oil at Low mark, I topped it up, lubricant was a little dark but no obvious water.

8. Engine always starts easily and runs fine at idle, or while cool.

It's dificult to access the carb, although the fuel pump and filters are available. The other side of the engine is somewhat accessible, and the head area is exposed under the companionway stairs.

I am tempted to remove the head but I'm experienced mechanically just enough to know that this may introduce more issues, and right now the engine runs, enough at least for local sailing.

I hope the forum can offer me suggestions to diagnose the problem. I am motivated, have tools, shore power, flashlights, and a multimeter. I can rent or borrow a compression tester and know what it is for.

Where do I go from here?

- Jon
Reply With Quote
  #2   IP: 96.229.195.76
Old 07-31-2012, 08:51 AM
Dave Neptune Dave Neptune is online now
Afourian MVP, Professor Emeritus
 
Join Date: Jan 2007
Location: Grove, Oklahoma
Posts: 5,035
Thanks: 711
Thanked 1,289 Times in 839 Posts
Lightbulb Sounds familiar sort of

Jon, first thing welcome to the Afourian Forum!
Lots os stuff listed to dig through. Did you check for spark when the engine stalled? Your ignition upgrade may not include the properly rated coil and it is "opening" once it gets hot and then "closes" after cooling to fire up again. There has been much todo regarding this on the forum.
As far as the coolant leaking do you see any in the bilge or leaking anywhere on the engine? If not and you are using that much coolant it's probably time to check the intake/exhaust manifolds integrity. Not to bad of a job.
Don't R&R the head unless it is needed and it is not YET! A simple compression check will let us know if you are loosing coolant throuugh the heads gasket. Have you done a compression check?
Remember to close the water intake while cranking in hard starting diagnosis so you don't fill the exhaust risking water encroachment from the exhaust side to the engine .

Dave Neptune
Reply With Quote
The Following User Says Thank You to Dave Neptune For This Useful Post:
TimBSmith (10-01-2020)
  #3   IP: 70.91.159.33
Old 07-31-2012, 09:17 AM
Bold Rascal's Avatar
Bold Rascal Bold Rascal is offline
Senior Member
 
Join Date: Mar 2011
Location: Princess Anne, MD
Posts: 302
Thanks: 0
Thanked 1 Time in 1 Post
Welcome Jon!

Your going to receive some very good advice from this forum.
If you already have a manual that's the first place I would start. Excellent trouble shooting guidelines are there. If you don't have one, get one....

180deg F is pretty close to normal temp for the A4.
The symptom of the engine failing and needing to cool before it will restart is most likely electrical. There have been many recent threads discussing this symptom.

The loss of coolant out the exhaust should be concerning. Hopefully it's just a failed gasket. Have you performed a thumb compression test on all cylinders? Do get yourself a compression tester and document your compression on each cyclinder. Your looking for consistent readings from all cylinders.

It's a Good idea to keep checking that oil for water contamination.

Do you need to choke your engine at all when starting it cold? If not or very little you might be running a tad rich on your fuel mixture.

If your satisfied that the engine runs well enough for local sailing it's your call to delay seeking out and correcting the problem(s). If you choose to sail be safe and extra deligent to monitor your engine and fluids at regular intervals. Like before, during and after each sail.

Again. welcome to the Forum.

Mike
__________________
Mike, Slower-Lower Eastern shore, MD
1973 Pearson 33
1967 Bristol 27

Last edited by Bold Rascal; 07-31-2012 at 09:20 AM.
Reply With Quote
  #4   IP: 24.152.131.155
Old 07-31-2012, 09:58 AM
ndutton's Avatar
ndutton ndutton is offline
Afourian MVP
 
Join Date: May 2009
Location: Torrance, CA
Posts: 9,619
Thanks: 198
Thanked 2,208 Times in 1,425 Posts
Compliments on a detailed description of symptoms, so detailed in fact that what's not there may be informative too. I think there might be a combination of problems.

Coolant loss
The first thing I'd do is pressure test the manifold. This can be done with the manifold on the engine and is pretty straightforward. The test will eliminate or confirm the manifold as the cause of the coolant loss and point you in a direction for repair.

Original stalling problem
It sounds like it may have been fuel related as you and the mechanic suspected. The addition of a fuel filter and hose replacement probably resolved any fuel contamination problems from then on but here's one of those things you didn't say. I didn't see where the carburetor was cleaned and rebuilt. If you've owned the boat for 6 years, had possible contamination problems and haven't rebuilt the carburetor, it's overdue. It should have been done when the filter was added for a complete repair. Even if the carburetor is clean, where's the harm?

Electronic ignition upgrade
We're all thinking the same thing. Let me ask this specific question though: you correlate the current stalling problem to engine temperature but can you instead tell us the time line in a stalling episode? What we're looking for is somewhere around 45 minutes run time before the engine slows and dies much like fuel starvation. Following a 20 minute or so cooling off period she'll start only to stall again after a little less run time.

Here's my guess of what's gone on:
  • 24 year old installation with a deteriorating fuel system. Possible hose decomposition due to ethanol in non-ethanol rated hoses and possible tank contamination. Issue resolved with hose replacement and filter addition.
  • Electronic ignition upgrade performed at the same time as the fuel system repairs which brought on another problem with similar symptoms as the previously resolved fuel issue. You traded one problem for another. I did not read the coil was replaced in the EI upgrade. This is critical with electronic ignition.
  • I don't think the coolant loss is contributing to the stalling problems.
__________________
Neil
1977 Catalina 30
San Pedro, California
prior boats 1987 Westsail 32, 1970 Catalina 22
Had my hands in a few others

Last edited by ndutton; 07-31-2012 at 10:01 AM. Reason: punctuation
Reply With Quote
  #5   IP: 184.70.15.142
Old 07-31-2012, 01:17 PM
Jon K Jon K is offline
Frequent Contributor
 
Join Date: Jul 2012
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
great suggestions, will follow up

Okay, Neil Mike and Dave, thanks for the quick response and your suggestions!

I will check the coil type and model, I assume it is new.

As for coolant, there is no obvious leak or coolant in the bilge, but I will put down a clean rag to see what it picks up.

The mainfold integrity tests -- does that mean I should remove the hoses and try to pressure test the exhaust manifold from outside the engine? I'll have to do some research on the forum to find out the best way to do that test.

As for how much choke when starting, I always use full choke when cold but it isn't needed when the engine is warm, however I have never tuned the carburetor. I will need to understand the carb and clean it at some point. So it may well be running rich right now, not sure.

Compression test, either with my thumb or a tester, that I will do asap as well.

To Neil's question of the timeline before stalling, 45 minutes is an average, never less than that anyway. If it is specific to how hot the engine gets, longer times before a stalling episode may occur during lower engine load/rpms I suppose.

I did make a 3.5 hour crossing only to stall on arrival when going to idle. That has happened three times at least after the cooled engine was restarted during a journey including last week.

And Mike, the reason I considered pulling the head was due a suggestion that there might be a blown head gasket. That is unconfirmed and would take me out of commission entirely until completed -- but I am committed to diagnosing and solving these issues with a still-running motor. I would rather sail/cruise but first priority is a reliable engine!

Also, I never knew about water encroachment via the exhaust, I will close that port next time I'm cranking for more than a few cycles. Will try to remember to open it after as well!

Thanks again for pointing me in the right direction, I'll return with more information.

- Jon
Reply With Quote
  #6   IP: 173.128.242.12
Old 07-31-2012, 02:23 PM
roadnsky's Avatar
roadnsky roadnsky is offline
Afourian MVP
 
Join Date: Dec 2008
Location: Lake Mead, NV
Posts: 3,104
Thanks: 24
Thanked 467 Times in 309 Posts
Jon-
Here are a couple of threads to read thru regarding your manifold testing...

http://www.moyermarine.com/forums/sh...+pressure+test

http://www.moyermarine.com/forums/sh...+pressure+test
__________________
-Jerry

'Lone Ranger'

1978 RANGER 30
Reply With Quote
The Following User Says Thank You to roadnsky For This Useful Post:
TimBSmith (10-01-2020)
  #7   IP: 184.70.15.142
Old 08-01-2012, 03:13 AM
Jon K Jon K is offline
Frequent Contributor
 
Join Date: Jul 2012
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
compression test, rich mix, run hot, ignition photo

I did a compression test with the following results.

All plugs were somewhat black with carbon.

Cold compression test

#1 - 90
#2 - 95
#3 - 100
#4 - 95

Oil pressure at high rpm: 34 psi

Engine started cold with no choke.

I ran the engine with saltwater cock closed, it soon overheated to 212/220 with lots of steam in the exhaust (photo below). In that process it ran hot (180 to 200) for 10 minutes without failure. Dropping to idle while the temp gauge read 220, it did not stall.

The electronic ignition seems to be the new item attached below the distributor (photo below). The new coil seems to be a tall black can 3 inches in diameter by 6 inches tall with the main distributor wire coming out of it. Both are new; no brand or model number visible.

I have attached today's photos of the steamy exhaust and oil pressure and temperature gauge during today's hot run, and a photo of the new ignition components.

Questions:

Still unclear about the steam in the exhaust -- what are the possibilities.

Does the compression test rule out head gasket failure or other issues.

If the ignition system (coil, electronic ignition and wires) came from Moyer last year, when the boat was in the shop, does the picture agree. If so, or if not, how to test coil failure etc.

Last year the mechanic ordered ignition parts from the East Coast, likely to have been Moyer Marine.

Neil's description of the failure scenario (45 minutes run time) seems very close to my symptoms. They seem to have persisted through a fuel system upgrade and electronic ignition upgrade. What does this indicate?

Thanks for the input,

- Jon
Reply With Quote
  #8   IP: 184.70.15.142
Old 08-01-2012, 03:18 AM
Jon K Jon K is offline
Frequent Contributor
 
Join Date: Jul 2012
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
photos from today's hot run

Here are photos of the exhaust when deliberately overheating the engine, the oil and temperature gauges at that time, and the new ignition system installed last year which did not solve my stalling problem.

- Jon
Attached Images
   
Reply With Quote
  #9   IP: 24.152.131.155
Old 08-03-2012, 01:28 AM
ndutton's Avatar
ndutton ndutton is offline
Afourian MVP
 
Join Date: May 2009
Location: Torrance, CA
Posts: 9,619
Thanks: 198
Thanked 2,208 Times in 1,425 Posts
First, the coolant
Considering the amount of steam, if this were coolant in the combustion chamber the plugs would show it - and they don't. The compression numbers are great. They may have been skewed up by coolant in the cylinder but again, the condition of the plugs indicates that's not the case. Your test with the raw water valve closed and copious amounts of steam still present leads me to a single conclusion - the manifold. You really need to do that test.

And . . . you now need to replace your impeller too. Running it dry for 10 minutes is destructive.

Quote:
Neil's description of the failure scenario (45 minutes run time) seems very close to my symptoms. They seem to have persisted through a fuel system upgrade and electronic ignition upgrade.
This assumes neither upgrade solved anything. As I said in my earlier post, I think your fuel system work either solved or came close to solving the original issue (see below for carburetor comments). But you changed more than one system simultaneously, usually considered to be bad form when troubleshooting.

You also upgraded to electronic ignition. You said you think the coil was replaced (looks new to me) but you can't say with what. You said it might be a Moyer coil but you're not certain. Your run time and failure symptom strongly suggests you have a coil of insufficient resistance for electronic ignition and it doesn't matter if it's new or not. It's the balance of your unique coil input voltage and the coil resistance that matters and coils come in a variety of resistances. A crude estimate is your coil resistance should be 4 ohms (Shawn, where did you get that Omega symbol I saw in another thread??) There's a painfully long thread on the subject found here. Note that the coil issue is unique to electronic ignition and entered into the mix when the ignition upgrade was performed. Also, it's not affected by engine running temperature, at least not the temperatures you are reporting.

I apologize for repeating what I theorized in my earlier post but I still think the current failures are unrelated to the previous failures. I think your fuel system work went a long way toward solving the original shut down issue then the installation of electronic ignition introduced a new issue with a low resistance coil. You're thinking the problem persists, I think the current problem is entirely different from the original problem. Please remember this is theory only, we're guessing the best we can.

About those plugs - their color indicates a mixture that's too rich as does this:
Quote:
Originally Posted by Jon K View Post
Engine started cold with no choke.
You're getting way too much fuel. A carburetor rebuild and dialing it in after reinstallation is in order. If you're apprehensive about it, consider Moyer's instructional video offerings.
__________________
Neil
1977 Catalina 30
San Pedro, California
prior boats 1987 Westsail 32, 1970 Catalina 22
Had my hands in a few others
Reply With Quote
  #10   IP: 206.125.176.5
Old 08-03-2012, 10:10 AM
sastanley's Avatar
sastanley sastanley is offline
Afourian MVP
 
Join Date: Sep 2008
Location: Solomons, MD
Posts: 7,016
Thanks: 1,134
Thanked 600 Times in 442 Posts
Thumbs up quick hijack

Quote:
Originally Posted by ndutton View Post
A crude estimate is your coil resistance should be 4 ohms (Shawn, where did you get that Omega symbol I saw in another thread??)
Neil - ALT + 234 on the number keypad gives you Ω.

Incidentally, ALT + 248 is °.

Here is a link to a resource. http://www.alt-codes.net/
__________________
-Shawn
"Holiday" - '89 Alura 35 #109
"Twice Around" - '77 C-30, #511 with original A-4 & MMI manifold - SOLD! (no longer a two boat owner!!)
http://www.moyermarine.com/forums/signaturepics/sigpic3231_6.gif
Reply With Quote
  #11   IP: 184.70.15.142
Old 08-03-2012, 02:04 PM
Jon K Jon K is offline
Frequent Contributor
 
Join Date: Jul 2012
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
next steps

Thanks Neil.

I'll do the following:

1. Test the coil resistance and post the results.

2. Try to find a cheap way to test the cooling system manifold pressure.

To do this I need to get some kind of pressure gauge into the system, and either run the engine and coolant pump to generate pressure or add a tire pump into the mix.

I'll have to see what I can do about finding a schraeder valve and coupling it into the cooling system to add a tire pump with a gauge, or another inexpensive alternative.

3. Yes, time to change the impeller. I have a spare from the previous owner but haven't replaced the impeller, just made sure I know where it goes and that I have tools to change it if necessary. I'll get a new one.

While thinking about this, I know there are two water pumps, the lower rear one has a grease cap that I should fill too. Do I need to service the coolant pump immediately?

4. My resistance to doing the carburetor rebuild is simply that, on my Ranger 28, the carb is located behind and below the access panel inside the cupboard beside the companionway stairs.

So I can see it from the cabin, and could possibly see my right hand going through the cupboard doorway, through the side access hatch and possibly reaching the carb with some kind of tools, since my head and arm don't both fit in the cupboard at the same time!

One of the strangest things I've seen in a while was the mechanic lying full-length inside the empty port cockpit locker, adjusting the gearbox. Quite a feat to get in and out I'm sure, and lots to bump your head on. The sole locker is usually chock-full of lines, fenders, boathook, ladder, shore power cable etc. I never considered it as an engine access method, but there you go.

I'll have to think through the carb work, at the very least take a good look at the manual to identify the screws and see if they can be adjusted without losing too much skin from my knuckles.

Thanks for the on-track advice.

- Jon
Reply With Quote
  #12   IP: 206.125.176.5
Old 08-03-2012, 02:19 PM
sastanley's Avatar
sastanley sastanley is offline
Afourian MVP
 
Join Date: Sep 2008
Location: Solomons, MD
Posts: 7,016
Thanks: 1,134
Thanked 600 Times in 442 Posts
Jon...a bicycle pump will work fine. The tricky part is the schrader valve to NPT fitting..some better hardware stores may carry them..or a place like McMaster Carr for sure, or even Amazon, has them.

Then you just need to cobble together a couple of bushings, reducers, etc. to thread it all together. By the way, the manifold threads are 3/8" NPT.

I've never had to do it myself, but, I am sure you can find more info here on this site with some creative searches, or maybe someone that has recently done so, can post their advice..
__________________
-Shawn
"Holiday" - '89 Alura 35 #109
"Twice Around" - '77 C-30, #511 with original A-4 & MMI manifold - SOLD! (no longer a two boat owner!!)
http://www.moyermarine.com/forums/signaturepics/sigpic3231_6.gif
Reply With Quote
  #13   IP: 24.152.131.155
Old 08-03-2012, 04:53 PM
ndutton's Avatar
ndutton ndutton is offline
Afourian MVP
 
Join Date: May 2009
Location: Torrance, CA
Posts: 9,619
Thanks: 198
Thanked 2,208 Times in 1,425 Posts
Jon,

I think your breach is big enough that you can test the manifold with your thumb as a gauge and a piece of 5/8" hose to blow in. Remove the two hoses on top of the manifold leaving the fittings in place. Clamp the test hose onto one fitting and blow into it with your thumb blocking the other. If you can develop enough pressure to either feel it on your thumb or turn your face red your manifold is intact, anything less and it isn't.

To test the coil, be sure to remove the wire(s) from at least one of the terminals and read the resistance between the two small terminals. To test it's suitability for your ignition system you also should measure the voltage between the coil + terminal and the engine block while the engine is running above 1000 RPM and then apply the formula or use the calculator, both found in the Coil Input thread (link provided in my previous post).

If it turns out that these tests result in properly operating systems, that's good information too. We can look elsewhere.

edit:
If you're concerned about carburetor access, all you really need access to are the cables, fuel line, scavenge tube and 2 mounting bolts. The delicate work is done on the bench. For adjustment after reinstallation, consider the Moyer idle adjusting needle with knurled extension. Get a 6" piece of fuel hose that's a snug fit over the knurled extension and use it as an extendo-handle to turn the adjustment screw, easily reachable from the front of the engine.
__________________
Neil
1977 Catalina 30
San Pedro, California
prior boats 1987 Westsail 32, 1970 Catalina 22
Had my hands in a few others

Last edited by ndutton; 08-03-2012 at 06:09 PM.
Reply With Quote
  #14   IP: 128.183.140.38
Old 08-08-2012, 10:46 AM
edwardc's Avatar
edwardc edwardc is offline
Afourian MVP
 
Join Date: Aug 2009
Location: Laurel, MD
Posts: 2,509
Thanks: 153
Thanked 595 Times in 388 Posts
Quote:
Originally Posted by sastanley View Post
Jon...a bicycle pump will work fine. The tricky part is the schrader valve to NPT fitting..some better hardware stores may carry them..or a place like McMaster Carr for sure, or even Amazon, has them.
I took a different approach to this. I bought an automobile tire rubber valve stem and used an xacto knife to cut off the "mushroom" part of the base. The remaining part of the valve stem could then be easily inserted into a hose and clamped to seal it. The other end of the hose then gets clamped onto one of the manifold fittings.
__________________
@(^.^)@ Ed
1977 Pearson P-323 "Dolce Vita"
with rebuilt Atomic-4

Reply With Quote
The Following User Says Thank You to edwardc For This Useful Post:
TimBSmith (10-01-2020)
  #15   IP: 98.237.173.224
Old 08-08-2012, 11:28 AM
Chris T Chris T is offline
Senior Member
 
Join Date: Nov 2004
Location: Tacoma. Washington
Posts: 36
Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by edwardc View Post
I took a different approach to this. I bought an automobile tire rubber valve stem and used an xacto knife to cut off the "mushroom" part of the base. The remaining part of the valve stem could then be easily inserted into a hose and clamped to seal it. The other end of the hose then gets clamped onto one of the manifold fittings.
Ingenious!!!!!!!!!!!!!!!!!
Reply With Quote
  #16   IP: 99.141.167.187
Old 08-08-2012, 07:47 PM
jbsoukup's Avatar
jbsoukup jbsoukup is offline
Afourian MVP
 
Join Date: Jan 2012
Location: chicago
Posts: 148
Thanks: 0
Thanked 12 Times in 9 Posts
IMHO #1 replace the coil - easy to do and relatively cheap.They are hard to test for heat related failure (you would have to first heat the coil to what temp?) #2 pressure test exhaust manifold - where else is all that coolant going if not inside or outside the engine
Reply With Quote
  #17   IP: 184.70.15.142
Old 08-31-2012, 12:57 AM
Jon K Jon K is offline
Frequent Contributor
 
Join Date: Jul 2012
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
More data points

Thanks to all of you for following up on this thread.

I finally got some time to continue gathering information, including what a Schraeder valve is, and why not to buy a bicycle pump at Walmart.

Here is what I know:

1. Engine loses coolant during regular use.

2. Engine stalls after 45 minutes to an hour of full speed, will not restart until it cools again.

3. Exhaust manifold cooling jacket holds 20 pounds of air pressure for 20 minutes.

4. Block cooling circuit from Obendorfer freshwater pump output hose to thermostat output coupling, with no thermostat, holds 22 pounds of air pressure for 20 minutes.

5. With the heat exchanger cap off, there are visible bubbles in the freshwater coolant, frothing when the engine revs to 2000 - 3000 rpm.

6. Freshwater pump looks good -- newish impeller and I sealed the gasket and tightened the screws.

7. Thermostat housing looks good -- cleaned and sealed the gasket, tightened the nuts.

8. Oil looks good -- no froth or other indication on the dipstick.

9. Cold compression test looks good -- no liquid, 90 - 105 compression.

10. Coolant hoses look good, and circuits test with good pressure.

11. Plugs are carboned, but mixture is rich.

So where is the steam coming from, and why does it lose coolant? At the beginning of this testing cycle there was no water or coolant in the bilge. Now of course there's lots because of changing the hoses and so on.

Where do I go from here? I could pressure test the heat exchanger, take her on a test run, or do the head gasket.

Is the head gasket a lot of work? I have access to the engine top and a few tools. The head bolts or nuts are rusty but I think they would come off.

If so, do I have the head machined or just add silicone to the gasket, or put new gaskets?

If I pressure test the heat exchanger freshwater circuit I might find air coming in. I could also replace all the hoses, although they and the heat exchanger look very new and clean.

I did hope that Neil was right about the exhaust cooling sleeve, but it holds tons of air. I got a tire valve stem, put it in a hose and clamp, and clamped it on. The other end I got a garden hose nipple, clamped it into a coolant hose, and added a garden hose close cap off my sprinkler to close it up. It took two tries tightening up until it held air, but the block cooling circuit and the exhaust manifold cooling circuit are tested without leaks. So I think it's not a cracked block, at least when cold.

Thanks in advance for your advice,

- Jon K.
Reply With Quote
  #18   IP: 24.152.131.155
Old 08-31-2012, 03:06 AM
ndutton's Avatar
ndutton ndutton is offline
Afourian MVP
 
Join Date: May 2009
Location: Torrance, CA
Posts: 9,619
Thanks: 198
Thanked 2,208 Times in 1,425 Posts
Your pressure testing indicates a sound block and manifold. I wouldn't touch the head gasket given these tests and your reported compression. The heat exchanger is next, cap on. It and the Oberdorfer FW pump are really the only components left.

Sounds like the coil is shot too.

Great testing and report. It's nice to have solid information.
__________________
Neil
1977 Catalina 30
San Pedro, California
prior boats 1987 Westsail 32, 1970 Catalina 22
Had my hands in a few others
Reply With Quote
  #19   IP: 24.224.206.117
Old 08-31-2012, 06:34 AM
Mo's Avatar
Mo Mo is offline
Afourian MVP
 
Join Date: Jun 2007
Location: Halifax NS,
Posts: 4,470
Thanks: 292
Thanked 411 Times in 272 Posts
Smile I`m with Neil.

My thoughts as well Neil and that sounds like it if there is no engine performance problems.
__________________
Mo

"Odyssey"
1976 C&C 30 MKI

The pessimist complains about the wind.
The optimist expects it to change.
The realist adjusts the sails.
...Sir William Arthur Ward.
Reply With Quote
  #20   IP: 184.70.15.142
Old 09-02-2012, 05:13 AM
Jon K Jon K is offline
Frequent Contributor
 
Join Date: Jul 2012
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Day 3 of 7

So if I close the saltwater cock to heat up the engine, where does the steam come from?

1. Pressure test of FW side of heat exchanger failed. It won't hold 5 pounds of air pressure.

2. Going to sail today, visiting friends cabin on Gambier Island. Change hoses to send raw water pump output to freshwater pump inlet, through engine to exhaust manifold cooling jacket, change hose to send manifold outlet to exhaust. Two pumps, lots of cooling. Engine at or below 100 degrees.

Voila, raw water cooling. Left the thermostat out so temp never got beyond 100 degrees. Checked that water temperature gauge sending unit was still in the system, it is beside the thermometer housing and reads correctly.

3. Ran under power for 1 hour, stopped then ran again for another 1 hour. Dropped to idle to lower mainsail, engine stalled. (Stall on idle is ongoing problem). Engine temp read 140 degrees. Possibly less cooling during idle, engine still hot?

4. Waited a few minutes, engine restarted and ran fine for another 20 minutes, had dinner. Came home 1.5 hours, engine temp 100 degrees, no issues.

Stall on idle problem happened at 2 hours, engine temp 140. When engine was cool, did not fail as before. I think this points to a temperature related problem.

Neil, the cold coil resistance is 3.1 ohms. I just read the coil thread, will try to think about that. Measure when hot?

Great to be on the water today/tonight, full moon guided us home. Trying not to think about the saltwater cooling the engine.

Answer: Steam caused by freshwater and antifreeze pushing into the saltwater circuit at the exchanger and out the exhaust. Seems a likely scenario.

- Jon K.
Reply With Quote
  #21   IP: 24.152.131.155
Old 09-02-2012, 09:45 AM
ndutton's Avatar
ndutton ndutton is offline
Afourian MVP
 
Join Date: May 2009
Location: Torrance, CA
Posts: 9,619
Thanks: 198
Thanked 2,208 Times in 1,425 Posts
Great post Jon

You have it surrounded Jon. Install a new heat exchanger and the cooling system issue is resolved. Nice work with the pressure testing. It took you directly to the problem without guesswork.

Your coil seems to be Okay although I'd still like to see one of slightly greater resistance for longevity (suggested on principle only). Given your history of shut downs I'd change it anyway.

As for the occasional stalling at idle, at what RPM do you customarily idle in gear? This could be as simple as a minor adjustment. Dare I ask, do you have a PCV valve installed?
__________________
Neil
1977 Catalina 30
San Pedro, California
prior boats 1987 Westsail 32, 1970 Catalina 22
Had my hands in a few others

Last edited by ndutton; 09-02-2012 at 09:49 AM.
Reply With Quote
The Following User Says Thank You to ndutton For This Useful Post:
TimBSmith (06-28-2023)
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Wiring spaghetti ndutton Electrical 35 09-07-2011 06:18 AM
Removing the engine from your boat Don Moyer General Interest 13 06-27-2008 11:06 AM
Engine stalling Bob N Fuel System 3 10-09-2006 05:22 PM
Removing the engine from your boat Don Moyer Ranger 7 12-12-2005 12:24 PM


All times are GMT -4. The time now is 01:57 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.


Universal® is a registered trademark of Westerbeke Corporation

Copyright © 2004-2024 Moyer Marine Inc.

All Rights Reserved