What temperature?

[BadaBing]

I now need to amend my temp vote. A little.I voted 160
. Today, after deciding I had worked on the New bimini dodger long enough, I decided to give her some exercise and burn off some of the small that will burn off the new exhaust tape.
Newly installed Dec with Johnson cm30 pump on the coolant side and the 501 pumping raw water through the HX. No thermostat.
After letting her warm a bit I put her in forward, let the floating dock chains come tight and the fender to find their happy place, then brought her to half throttle. It took about 10 minutes and she combed to 170. Sensing she wanted more I brought her to 3/4 throttle. (Tide was going out and its a good way to keep the hole under my boat deep)
After a few minutes the temp climbed to just under 180 and held there. I let her like that for about 5 minutes before backing down to idle. The temp came back down as well.
After shutting her off I turned the key back on to cause the coolant pump is to run and as mentioned by others the temp was now about 20 degrees below where it was reading just the moment before. Don't know what's up with that but it all looks good from here.

[JOHN COOKSON]

After shutting her off I turned the key back on to cause the coolant pump is to run and as mentioned by others the temp was now about 20 degrees below where it was reading just the moment before. Don't know what's up with that but it all looks good from here.

Possible sticky gauge. Next time this happens try tapping gently on the gauge with a screwdriver handle.

TRUE GRIT

[Mo]

I now need to amend my temp vote. A little.I voted 160
. Today, after deciding I had worked on the New bimini dodger long enough, I decided to give her some exercise and burn off some of the small that will burn off the new exhaust tape.
Newly installed Dec with Johnson cm30 pump on the coolant side and the 501 pumping raw water through the HX. No thermostat.
After letting her warm a bit I put her in forward, let the floating dock chains come tight and the fender to find their happy place, then brought her to half throttle. It took about 10 minutes and she combed to 170. Sensing she wanted more I brought her to 3/4 throttle. (Tide was going out and its a good way to keep the hole under my boat deep)
After a few minutes the temp climbed to just under 180 and held there. I let her like that for about 5 minutes before backing down to idle. The temp came back down as well.
After shutting her off I turned the key back on to cause the coolant pump is to run and as mentioned by others the temp was now about 20 degrees below where it was reading just the moment before. Don't know what's up with that but it all looks good from here.

Sounds about what to expect. I find my own boat, RWC and no T-stat, will hang around 140 cruising at 5-6 kts in relatively calm sea.
With FWC the engine will only cool as much as the capacity of the heat exchanger's abilitiy to transfer heat. Of course, there are a few factors involved there: RW flow volume, size of heat exchanger, temp of RW, integrity of system and FW pump flow rates....I think you are running pretty good as described

PS my earlier post on this thread says my temp doesn't go over 130...the guage doesn't. I bought one of those infra red thermometers and now check my temps with it...much more accurate...she's 142 degrees just moving in good weather and maybe a few degrees above that when slugging it out in bad weather...not bad.
.

[hanleyclifford]

I now need to amend my temp vote. A little.I voted 160
. Today, after deciding I had worked on the New bimini dodger long enough, I decided to give her some exercise and burn off some of the small that will burn off the new exhaust tape.
Newly installed Dec with Johnson cm30 pump on the coolant side and the 501 pumping raw water through the HX. No thermostat.
After letting her warm a bit I put her in forward, let the floating dock chains come tight and the fender to find their happy place, then brought her to half throttle. It took about 10 minutes and she combed to 170. Sensing she wanted more I brought her to 3/4 throttle. (Tide was going out and its a good way to keep the hole under my boat deep)
After a few minutes the temp climbed to just under 180 and held there. I let her like that for about 5 minutes before backing down to idle. The temp came back down as well.
After shutting her off I turned the key back on to cause the coolant pump is to run and as mentioned by others the temp was now about 20 degrees below where it was reading just the moment before. Don't know what's up with that but it all looks good from here.

Some temp senders operate on voltage differential and the fact that you shut down and continued running a pump could influence voltage being delivered to the temp gauge. Neil may know more about this.

[ndutton]

Except for the bourdon tube type, all temp gauges operate on voltage variation. Although I've never tested, it's logical to me that there would be a difference in temp gauge readings at the same temperature when the engine is running with the alternator driving the system voltage and when it is not.

Of much greater concern is running the electric coolant pump by turning the keyswitch to ign and the engine not running. The risk to the coil far outweighs any cooling benefit. Plus, without raw water running through the HX I doubt there's much cooling benefit anyway.

[hanleyclifford]

A good argument could be made for having two temperature gauges since the coolant temperature is going to vary widely at different points in the loop. I also believe calibration varies even on the best quality gauges. Presently I am sensing for the electric gauge at a point nearest the UHS where I believe the highest reading can be had; but who knows what the temperature at the coolant pump might be after it (the coolant) has passed thru the exchanger(s)?

[zellerj]

re: an forum exchange from 2011. Thought I should update what I found out.

I bought my 1982 Catalina 30 in 2000 from a guy that had it 12 years, and he said that it always ran at 210 with no issues. I've owned it for 11 years, checked the thermostat a number of times, acid flushed, put a larger shoe in the water pump, made sure there is plenty of flow out the back , and it still runs at 210. I put in a manual analog gauge and that read 210, so my gauge is working properly.

I have recently purchased an infrared thermometer and the top of the cylinder head reads from 150 to 180 - only very close to the spark plug will I see a reading of 210.

My question is - could the temp gauge be picking up a stream of hot water (sort of like a warm current) from the head so that the gauge does not measure the average block temperature?

Best,
Jim

and a reply from Neil:

I have a few questions Jim,
Checked the thermostat? How, stove top test? At what temp did it open?
What condition is the inside of the thermostat housing, clean and sharp edges on the inside of the dome or corroded, eroded and rounded over?
Raw water or fresh water cooled?
Moyer bypass valve or not? If so, closed or not?
Have you removed the side cover plate to physically look (and muck out) the water jacket and examine or replace the diverter cap?...

Update: While replacing my alternator I could not help but take off my water diverter plate because it was so exposed. I found a bunch of old black organic matter that had plugged up a lot of water passageways going to the head. I cleaned these out the best I could using a dental pick, re-installed the plate, new alternator, and then cleaned out the water exit fitting of the manifold. Was very glad to see the temperature settle in at 145-150 F. Water flow was not noticeably different. I sail in a fresh water lake (Lake Erie) and am raw water cooled.

My conclusion: if your temp gauge reads hot, shoot the head with a infrared thermometer to see what the temp of the head really is before you panic and get a tow etc. My A4 was at 210 F at the gauge for at least 12 years with no damage, because the head was not at that temperature. If the head is at a reasonable temp with the infrared gauge, then you can fix the problem at your leisure.

Best,
Jim

[hanleyclifford]

re: an forum exchange from 2011. Thought I should update what I found out.



and a reply from Neil:

Update: While replacing my alternator I could not help but take off my water diverter plate because it was so exposed. I found a bunch of old black organic matter that had plugged up a lot of water passageways going to the head. I cleaned these out the best I could using a dental pick, re-installed the plate, new alternator, and then cleaned out the water exit fitting of the manifold. Was very glad to see the temperature settle in at 145-150 F. Water flow was not noticeably different. I sail in a fresh water lake (Lake Erie) and am raw water cooled.

My conclusion: if your temp gauge reads hot, shoot the head with a infrared thermometer to see what the temp of the head really is before you panic and get a tow etc. My A4 was at 210 F at the gauge for at least 12 years with no damage, because the head was not at that temperature. If the head is at a reasonable temp with the infrared gauge, then you can fix the problem at your leisure.

Best,
Jim

This story is a good illustration of how tolerant the Atomic 4 can be. For 12 years your block was being cooled unevenly and for all practical purposes you did not know whether you were overheating or not. At the least you block was subjected to uneven cooling, but favoring the area near the cylinders where it really counts. The black goo and attendant plugging of passageways is evidence that Lake Erie is not as "fresh" as was thought.

[Van_Isle]

Running 140-150 .... that's not bad. I wouldn't be sweating that.

I must admit I'm a little gun-shy on temperature.

Two years ago, I had the engine rebuilt .... well I always say 'rebuilt' but in reality it was 'replaced' as the shop that did the work started with a used FWC block they had. They felt it was easier to use that block than the RWC one I had .... but I also acquired (for the cost of a bottle of scotch and a bottle of gin) a complete 2nd engine (disassembled) that had a heat exchanger with it. They didn't use that block due to some known issues with it, but it, and my old engine, supplied a lot of parts, not the least of which was a replacement head for mine, which was cracked.

The process kinda went this way:

1) I asked the guy doing the work (40+ years experience and a former Universal factory rep) a number of times if they were going to send out the heat exchanger to be boiled and pressure tested. Answer was 'yeah, we still have to do that'.
2) The weekend before putting it back in I am handed the old HX and 'told' to take it home and soak it in CLR .... and clean up the exterior (it's about at this time I discover that their sandblaster has been broken during the rebuild and they've spent countless hours wire-wheeling parts to clean them up.
3) Like the idiot I am, I spend a significant amount of time over the weekend soaking, scraping, sanding, etc. inside and out. It looks pretty darn good!
4) Monday AM I bring it back and am told ... oh, the connections are the wrong size ... we can't use this. Huh? Ahh ... it came off an A4??
5) So they say ... well we have another one here (pulls off shelf) and it's been boiled and pressure-tested so we'll just swap it. Seems to be a ok solution in my mind.
6) Everything installed and (supposedly) tested. I'm told 'ready to go!'. Down with the family that evening to motor back to our berth (about 30 minutes away).
7) Running fine, but a bit hot in my mind ... close to 200. But I've got about 24-hours motoring time experience with the boat and that was the old RWC engine (complete with near fire on board ... but that's another story!).
8) 20 minutes into it, into the channel to our berth and it's ebb tide so straight into the current ... have to throttle-up a bit. I get distracted for a couple minutes monitoring engine when ...
9) my wife calls from up forward 'what's all that white smoke!!!?' OMG!! No water out the exhaust! Temp is pegged at 250! Oil pressure is zero! My hand reaches for the ignition switch and at the same time a huge 'SCREETCH!!' followed by a loud 'BANG!' and a high-pitched 'PHHHHHT!' sound
10) and we went round in circles in no wind until a buddy comes by in his zodiac to tow us in.

So who can guess what happened??

[Easy Rider]

Three possible answers:

1. The "expert mechanic's" credentials are questionable.
2. HX faulty or wrongly connected.
3. You never took your wife out again for yelling at you.

Anxiously awaiting the next installment!

Chuck

[Van_Isle]

Close! I'll do this in reverse order:

3. I am amazed my wife has gone out with me again! This was her 1st time on the boat!

2. Now the HX was initially installed incorrectly ... but I quickly brought-up the fact that anti-freeze was pumping out the exhaust during the first start-up! That was resolved in short order.

1. You be the judge (I've been writing this since my previous post, case you were wondering):

1) The 'SCREETCH' was the raw water pump impellor running dry.
2) The 'BANG' was the hose from the HX to the overflow bottle blowing out (not off ... the hose actually failed).
3) The 'PHHHHT' was a mix of anti-freeze and raw water escaping from said hole in the hose.
4) So during the rebuild, I picked up a generic plastic overflow bottle from the local autoparts store. That specific type has a connection on the bottom but the hole is plugged ... it can also be used as a windshield washer bottle. Written instructions provided. ... they didn't drill the hole out!
5) But the HX also failed. I'm not sure if it was due to overpressure in the system, botched pressure-test, or perhaps I got a blockage ... or a combo.
6) So the whole thing overheated, and not being able to expand out into the tank, the hose blew-out.

The fix, and further discoveries:

1) The shop replaced the impellor on the raw water pump. The raw water impellor is intact, but completely separated from the shaft. I question the fresh water (old raw water) impellor ... I pull it ... well it's obvious to me that they didn't open the pump during the rebuild, but it seems fine. Replace it anyway.
2) Engine forward and reverse flushed multiple times (by me).
3) HX sent out, repaired, pressure tested and re-installed, with a new overflow bottle (complete with drilled hole), by the shop.
4) Tested at the dock ... still running at 200. I question this (and do a fair bit of reading here on this site!)
5) I borrow a kit and pressure test the HX and the cap ... they are fine.
6) I come-up with the idea that the thermostat should be checked. (remember this is a 'new' head). I pull the thermostat ... a Holley (if I remember correctly) and obvious it wasn't cleaned up during the rebuild. Neither was the thermostat housing! I soak thermostat in cleaning vinegar, clean up the housing and the shop does a stove-top test. The thermostat is barely opening!
7) I check thermostat prices ... and when I stop hyper-ventilating, I grab the thermostat from my old RWC block. Into the vinegar and I do a stovetop test myself. This one is fine.
8) Pop it in ... hmm ... 180 to 190 at dockside.
9) I borrow an infra-red thermometer from the shop ... head temps seem fine.
10) The guy at the shop imparts the pearl that when they put the engine back in, the temperature gauge didn't work. He replaced the sensor. Was it matched to the gauge, I ask? 'Oh, those things are universal!', he says. I investigate ... the sender he pulled off their shelf is an oddball unit that barely shows-up any info online ... I phone the company and am told it's a dual-station model ... hmmm! I am told by the guy in the shop that he couldn't get the exact match .... but this one should be fine. Can't get one?? For a Faria temp gauge?? I drive 2 miles to the local NAPA and ... they've got the exact correct sender in stock ... huh!
11) New sender installed. Temp now reads 140 to 150!
12) I install a low oil pressure and high-temperature alarm.
13) Dockside run-up, with the shop. The guy manages to get the orange alternator wire caught in the fan. He, who did the wiring hook-ups, says 'You should clean-up that wiring!'
14) Shake-down cruise, with the guys from the shop. The trans is slipping in forward. They adjust it (perhaps another contributing factor?)
15) 2-hour shake-down cruise, with the guys from the shop. All seems good (except he doesn't have the idle set quite right and stalls it coming back alongside ... big gouge in the port bow!).
16) Use the boat for a couple weeks ... and note there is an oil leak somewhere at the rear of the engine, maybe on the tranny ... I track it down to a missing bolt! Shop puts a new one in.
17) I discover a couple of the hoses are weeping ... sloppy work on the connections.
18) The guy who did the engine rebuild is banned by me from doing any further work on the boat. And interestingly, he no longer works there.

[Mo]

There are few things as disheartening as engine issues occurring following major work. I rebuilt an engine in my Toyota pickup, in the evenings, as I was going through medical training in the military. Between learning how to rebuild an engine and the intense study from the medical side of things...there was no time for anything else.

4 days prior to graduation the truck was done and I fired it up. Fired up perfect then blue smoke started to pile out the exhaust pipe....I was heart broken and the temper flared. Picked up a piece of pipe and was going to pound the ---- out of the truck. There were a couple of other guys in the hobby shop and one stopped me and said "hold up there young dude"... he remembered when I drove it in there she was pouring thick smoke out the exhaust and when the engine was broken down the rings of number 4 piston were in the base pan....

The smoke stopped after about 5 to 10 minutes....it was literally oil burning off the inside of the exhaust that had been forced in by compression when the engine went. I almost needed a body job after that because I so friggin mad....anyway....I'll never forget that feeling after all that work, sacrifice of time and sleep....BTW, the engine ran perfect for years later and never used a drop of oil between changes.

[hanleyclifford]

I hope you now see that you are the best "expert" on your installation. This is almost always true due to the esoteric nature of our A4 installations. In the future come here first where your true A4 family exists. FWIW. Post pictures.

[Vermonstah]

ouch

Van - that is quite the aggravating ordeal.

i too am very sensitive about temps. Maiden voyage after taking ownership, I melted a plastic water lift muffler. Yes, sir. Plastic! Horrible design but alerted me to an overheating issue .... I chased down the repair on that for the remainder of that season and the next as the overheating damaged the head gasket etc. And i was doing my own work, occasionally making things worse before better. But I eventually learned some things about my engine and subsequently my boat. I think I have it sorted out now and so very exciting for the upcoming season!

Back to the thread topic - temperature. I have RWC on a somewhat cold lake, Lake Champlain is not Lake Superior cold but still rather cold for much of the sailing season. Once again, this year we could still have some ice in the mooring field when it opens on May 1st.

I have limited boat bucks in this year's budget, so is there any general consensus as to what should be my top priority:

1. Control temp by adding FWC

or

2. Monitor temp and other key performance parameters by adding the EWDS.

I am not exactly confident in my ability to install either so I am currently not factoring that into my decision.

Thanks,
Brian

[Van_Isle]

I hope you now see that you are the best "expert" on your installation. This is almost always true due to the esoteric nature of our A4 installations. In the future come here first where your true A4 family exists. FWIW. Post pictures.

I'm gaining more and more knowledge and 'level of comfort' on the engine as I go along.

Pics are here: http://www.moyermarine.com/forums/showthread.php?t=7615