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-   -   Engine died after running for hours (https://www.moyermarineforum.com/forums/showthread.php?t=11509)

SeaHarlequin 05-29-2020 01:38 PM

Engine died after running for hours
 
Hi - this forum has been a big help in my gaining an understanding and trust in my Atomic 4 which I bought last year. Thank you!

Unfortunately, that trust was severely undermined when my engine died and I'm hoping for some ideas on identifying the root issue.

I have the Moyer manual and with help from the forum, I've replaced all spark plugs, changed the oil, installed a new ignition coil, cleaned the carb, and run compression tests. This engine is awesome and I've run it about 20 hours in the SF Bay without any issues.

On Monday, after running it about 6 hours, I filled the gas up and put it away. Yesterday, I took it out and motored for about 4 hours. We were getting hammered by some swell and were rocking around. The engine suddenly died. I was able to get it started again and motor for about 45 minutes before it died again.

The only major differences that I can think of are the gas (maybe it was dirty but why run for 4 hours if that's the case) or, according to the Moyer manual's fuel system troubleshooting section:
  • The vent line to the fuel tank became clogged (could getting rocked with a tank that is almost full slosh gasoline in a way that it clogs the fuel vent line?)
  • the fuel pump failed (I don't think this is case since it's an electric fuel pump and the engine started back up once in the slip again.)
  • Oil safety switch failed (I don't think this is the case for the same reasons as above.)
  • Dirt in the bottom of fuel tank or pick-up tube. I plan to remove and clean the pick up tube and check the supply / fuel lines but don't think this is the problem either because we motored for 4 hours before the shutting down issue happened.

While the engine seems to be working again, I want to regain confidence in the engine to ensure this doesn't happen again and the best way for me to do that is to pinpoint the root cause. I'd appreciate any ideas or suggestions in pinpointing the issue. Thanks!

Sam 05-29-2020 04:13 PM

Few years back I had a similar problem a day after riding through a rough storm - lost rpm and engine would die and retart/run and repeat. I did not think it was fuel related because of recent fill up. I drained the tank and shined an inspection light into it and was amazed at the crud/gunk on the bottom. I started there- cleaned the tank repeatedly, updated the fuel lines to A1 low permutation [needed for ethanol], new fuel filter, changed the electric fuel pump [there is built in a filter inside], cleaned the carb AND most importantly added a 0-15psi fuel pressure gauge. This will help with any diagnostics regarding fuel vs spark.

SeaHarlequin 05-29-2020 04:49 PM

That's a good suggestion; the tank is translucent so I can see the fuel level and things seem relatively clean but there might very well be gunk sitting on the bottom that's getting stirred up. I'll plan on draining the tank this weekend and getting a good look at the tank itself.

I feel silly but while I've recently replaced the main gasoline filter and the fine in-line filter, I didn't consider that the fuel pump itself might have a built-in filter. I'll check into that.

Adding the psi gauge also sounds like a no-brainer -- should've done that.

Thanks for the suggestions! I now have my weekend tasks planned out. :D

Surcouf 05-29-2020 04:53 PM

I feel silly but while I've recently replaced the main gasoline filter and the fine in-line filter, I didn't consider that the fuel pump itself might have a built-in filter. I'll check into that.

[/QUOTE]

I had no idea neither before I saw that one
http://www.moyermarineforum.com/foru...ghlight=filter

Peter 05-29-2020 05:07 PM

Harlequin,

You mention wanting to pinpoint the cause to get your confidence back. I think you will also save a lot of time and $ if you pinpoint the cause as opposed to just trying things and hoping that was the problem.

May I suggest a that fuel pressure gauge is in order? It will tell you explicitly if there is a fuel delivery issue. The cost is low, they are easy to install and they are endlessly useful. I initially installed one because I suspected a fuel problem and sure enough that was the issue. In fact, I had my problem and was going to post a query to the forum and realized that the first question I would get is "Do you have a fuel pressure gauge?" So I installed one and was able to diagnose the problem myself - dirty fuel tank was my ultimate conclusion.

I reached this by verifying that:

1) Fuel pressure was good and engine ran fine when run off an auxiliary tank
2) Things got dodgy when I introduces my filter between the aux tank and the engine.
3) Examination of the filter revealed it was full of crap
4) Crap must have come from the tank.
5) Removed and cleaned tank - all well since then.

I have since had stalls and it was once again fuel pressure - I forget sometimes to open the fuel shut-off valve...

Careful diagnosis is the key to having confidence in your engine AND your ability to trouble shoot issue when underway.

Best,

Peter

SeaHarlequin 05-29-2020 05:18 PM

That's a very good point, starting off with a fuel pressure gauge as that would give the maximum ROI in terms of accurately pinpointing the root issue. I'll get that into place and establish baselines before starting on the other processes.

Many thanks to you all for the ideas!

ndutton 05-29-2020 09:54 PM

Don't get tunnel vision on what you think might be the problem or that it is a single problem. Nothing is off the table when you begin your testing. Your description suggests a dirty tank but for example and not mentioned yet are possible issues related to your recent filter work. A loose fitting or hose clamp can produce a vacuum leak in the fuel line introducing air. That will stop an engine just as well as anything.

SeaHarlequin 05-29-2020 10:44 PM

Good advice; I'll try not to get tunnel vision nor restrict my thinking to one potential issue.

Quote:

Originally Posted by ndutton (Post 121419)
possible issues related to your recent filter work

How dare you! :D Yep, I'll be going through processes of elimination and let the facts lead me where they may... even if it's to something (or several things) I screwed up.

roadnsky 05-30-2020 10:37 AM

Quote:

Originally Posted by SeaHarlequin (Post 121403)
I've replaced all spark plugs, changed the oil, installed a new ignition coil...

As others have said including yourself, it's likely fuel.
Adding a pressure gauge is a great help.

As Neil said, let's keep an open mind to other possible issues too.

Quote:

The engine suddenly died. I was able to get it started again and motor for about 45 minutes before it died again
While we're here, what about that coil?
Do you have EI by chance?

SeaHarlequin 05-30-2020 10:29 PM

Yes, I have EI. The coil was replaced a couple of months ago so I don't think it's related to the recent incident.

Today, I got out to the boat and installed a pressure gauge on the fuel line after the electronic fuel pump and inline fuel filter -- it read about 2 PSI which, to my understanding, meets operating specs.

I also opened the fuel pump to access the filter (mainly because I didn't know it existed and I wanted to see it) -- that was clean.

Now, I've removed the carb and will be hitting it with some carb cleaner. I've not rebuilt a carb before and am hoping spraying carb cleaner will suffice since I don't have a feel for how involved rebuilding a carb is.

As a baseline, I tried starting the boat several times when I got there today. It would not start. After removing the fuel line to install the pressure gauge, the engine started up. I'm assuming something may have clogged the carb (or the needle got stuck) and the rapid release of pressure when I removed the gas lines back-flowed the debris/needle. Does that sound plausible?

SeaHarlequin 05-30-2020 10:30 PM

@ roadnsky - Just noticed your avatar. Nice ranger! :) I have a 1974 29' Ranger!

roadnsky 05-31-2020 07:47 PM

3 Attachment(s)
Thanks
Ranger is a great boat and our "home away from home"

Administrator 05-31-2020 08:41 PM

Beautiful!

Bill

SeaHarlequin 05-31-2020 11:03 PM

Agreed! That's a beautiful boat! It's surprising how much larger the interior looks considering mine is "only" a foot smaller. I like the quality of your cabinet work! You also reminded me I need to get my boat painted. :D In my defense, most of the scuff marks are from the previous owner although I can claim responsibility for one (or two, but let's not quibble).

http://www.moyermarineforum.com/foru...pictureid=2057

http://www.moyermarineforum.com/foru...pictureid=2056

Today, I cleaned out the carb. A few months ago, I sprayed carb cleaner into the openings but didn't disassemble it. Today, I disassembled it, taking care preserve the gasket, and in addition to shooting carb cleaned into orifices, used a thin wire to clean the idle jets, and then hit everything, including all inlets, with an air compressor.

Now that I've done it, I don't know why I took so long to do so. I was a bit apprehensive but in seeing how easy it was, I'd recommend it for anyone contemplating it. Of course, if I've somehow hosed the entire carb, I may end up eating those words. :eek:

I had a full face mask on, took care to try to predict where the carb cleaner would go, and I still got surprised twice by splash back so that's something I'd strongly recommend for someone approaching it for the first time -- that carb cleaner goes in surprising directions: BE CAREFUL and protect your eyes.

Hopefully, I can just slap the carb into the boat next weekend and go sailing!

My current plan is to try to run the fuel tank down to <5gal then extract the remainder into a container and hopefully get most of any dregs/particulate off the bottom. I'm hoping to let that sit for a while undisturbed and see if I can find water or particulate in the container. I'm also planning on replacing the old fuel lines then trying to inspect them for hairline cracks as I bend them. Hopefully between those two actions, I can reasonably infer the culprit(s). Ideas/suggestions would be appreciated.

JOHN COOKSON 06-01-2020 01:06 AM

If you can get into the tank (maybe through the top outlet opening?) you can attach length of tubing to a stick (cable ties) then use the stick to guide the tube to the lowest part of the tank.

If you can't find the cause of the shut downs try shorting across or bypassing the OPSS. An OPSS can fail in all sort of weird manners. Been down this road.

ex TRUE GRIT

The diagnostic test for tank or some other problem in the fuel system is to run off an auxiliary tank. See post #5 (1)

SeaHarlequin 06-01-2020 03:47 AM

Guiding a stick to access the low part of the tank is great idea; now that you mention it, I think I recall seeing a tank access plate which would make that idea a breeze.

I did have issues with the OPSS once before, I'll re-check that.

Thank you for the reminder about the auxiliary tank. I don't have an extra tank so hopefully I can pinpoint the issue and resolve it before I need to buy one. :D

hpweisse 09-02-2020 03:47 PM

Quote:

Originally Posted by Sam (Post 121408)
Few years back I had a similar problem a day after riding through a rough storm - lost rpm and engine would die and retart/run and repeat. I did not think it was fuel related because of recent fill up. I drained the tank and shined an inspection light into it and was amazed at the crud/gunk on the bottom. I started there- cleaned the tank repeatedly, updated the fuel lines to A1 low permutation [needed for ethanol], new fuel filter, changed the electric fuel pump [there is built in a filter inside], cleaned the carb AND most importantly added a 0-15psi fuel pressure gauge. This will help with any diagnostics regarding fuel vs spark.

And only use Marine or non-ethanol gas. Ethanol is water absorbant, especially if it sits a few weeks. Look for tank stations posting ‘non-ethanol gas,’ or fill up at the gas docks.

sastanley 09-03-2020 12:47 AM

Quote:

Originally Posted by hpweisse (Post 122708)
And only use Marine or non-ethanol gas. Ethanol is water absorbant, especially if it sits a few weeks. Look for tank stations posting ‘non-ethanol gas,’ or fill up at the gas docks.

http://pure-gas.org - I would not guarantee that 'marine gas' is E-zero.

ndutton 09-03-2020 08:55 AM

Quote:

Originally Posted by hpweisse (Post 122708)
And only use Marine or non-ethanol gas. Ethanol is water absorbant, especially if it sits a few weeks. Look for tank stations posting ‘non-ethanol gas,’ or fill up at the gas docks.

For the ethanol alarmists, I've run on a steady diet of E-10 (10% ethanol blend) for 15 years with only a single fuel related shut down and it had nothing to do with ethanol.

Dave Neptune 09-03-2020 10:02 AM

I too ran on E-10 right up until I sold the boat and never an issue with the "fuel". I did have one fuel failure at the dock when my mechanical pump shot craps. I LOOKED AT THE FUEL PRESSURE GUAGE for diagnosis and it read zero:D. Twenty minutes later we were on our way to Catalina with no OPSS and a "hot wired electric pump.

The problem with the E-10 is not the fuel but how long it is stored. Some boats use the engine just to get in an out of the slip so a tank may actually last a few years:eek:. Those who cruise a lot like me use up the fuel long before any problems occur:rolleyes:.

Dave Neptune :cool:


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