Got the engine Started! Now to trouble shoot odd running patterns

[LemonShark2]

Hi All,

After posting a few weeks back about my engine not running due to what I thought was water in the fuel, I made some significant progress. Siphoned out the fuel and separated out the water, as well as emptying the fuel filter, and fuel bowl right before the carb, which also had water in it. I primed the whole line up to the bulb, and hooked it back up.

I also changed the Oil, which was black as hell, but not milky, so at least there wasn't water in there!

I tried starting it a number of times, to no avail. I popped out a spark plug, and noticed it as bone dry, so I went ahead and used the hand primer about 100 times (should it have resistance? I didn't feel any pressure.)

After a couple of tries, I got it running again, for about 10 minutes, however the action of the engine, and its running pattern was very odd! At higher throttle, it did this odd thing (see video) I turned it off after getting nervous.

https://youtu.be/qBRTHbDxUtQ

Here it is with the throttle just about where I usually leave it for idling. Sounds Healthy! Except then I noticed a bit of smoke...

https://youtu.be/IiTCR2vL4Ig

It eventually stalled - my theory is overheating - check out the water out the exhaust. I remember reading it should be a steadyish stream, where as mine is just spitting it out bit by bit. Doesn't help that my thermometer isn't working.

https://youtu.be/aaNws3w5dqA

So hoping this is just my flexible impeller needing replacement, so i yanked it out and am about to order one...

At the very least, I'm happy I got it running - as I feel like a running engine, even if not running well, is probably better than a non-running engine!

Bonus video, you kinda see how much amazing engine access I have to work with... Maybe youll also spot something I need to fix!

https://youtu.be/X_Ci1MTmcQQ

[hanleyclifford]

Your engine looks good and sounds good; I would like to see more water coming out of that exhaust. Check the usual suspects for restrictions.

[ndutton]

Looks to me like you're still dealing with contaminated fuel/dirty carburetor problems. In your post I did not see where you:

• disassembled and thoroughly cleaned the carburetor
• cleaned the fuel tank interior
• determined the source of the water incursion in the tank and repaired so it never happens again
• discarded the questionable fuel and refilled with fresh

The water flow out the exhaust looks normal to me considering the low RPM in the video but there's certainly no harm in replacing the impeller anyway. Is there any real indication of overheating beyond your theory? What is the history of this engine?

[JOHN COOKSON]

A Few Ideas

Are you sure that nothing wrapped around the prop?

The smoke could be from hot running. Are you RWC? It looked like it in the videos. Let's start with a little diagnosis before you start replacing cooling system parts. Low water flow can be caused by a of a few things. Partially blocked inlet to the water pump. Water pump impeller shot. Blockage of flow through the engine ie a thermostat that is stuck closed or blocked engine cooling passages. Another common place for blockages it is at the manifold outlet.The usual method of diagnosis for a RWC engine is to start at one end or the other of the cooling system and find out where the water flow is reduced.

If running off an auxiliary fuel tank solves the fuel problem then the problem is before the fuel pump. If you still have fuel problems while running with the auxiliary tank then the problem is with the fuel pump and\or the carb.

How long has it been since you've had a look at the distributor advance?

Hang in there. You're getting close.

TRUE GRIT

[LemonShark2]

Reply to ndutton

Looks to me like you're still dealing with contaminated fuel/dirty carburetor problems. In your post I did not see where you:

• disassembled and thoroughly cleaned the carburetor
• cleaned the fuel tank interior
• determined the source of the water incursion in the tank and repaired so it never happens again
• discarded the questionable fuel and refilled with fresh

The water flow out the exhaust looks normal to me considering the low RPM in the video but there's certainly no harm in replacing the impeller anyway. Is there any real indication of overheating beyond your theory? What is the history of this engine?

1. Previous owner said he had the serviced the Carb. Might be time to do it again as he didn't seem to visit the boat often.

2. I haven't cleaned the fuel tank interior, though am considering just getting a new tank.

3. Water got in because a friend left the fuel cap off in Seattle for a week (rain water went down the chute).

4. I filtered out all fuel, let the water separate, then siphoned most not all back into the tank. Next step is to top of the tank and add some fuel treatment.

it sounds like maybe something to do with the carburetor or the main mechanical fuel pump, so I guess that'll be next weekends project...

I do think that 2 owners back, the engine was worked on using moyer marine parts/manual, and possibly some love and TLC put in. A few years between then and now, and I think the engine needs another bout of love...

[LemonShark2]

reply to JOHN COOKSON

Are you sure that nothing wrapped around the prop?

The smoke could be from hot running. Are you RWC? It looked like it in the videos. Let's start with a little diagnosis before you start replacing cooling system parts. Low water flow can be caused by a of a few things. Partially blocked inlet to the water pump. Water pump impeller shot. Blockage of flow through the engine ie a thermostat that is stuck closed or blocked engine cooling passages. Another common place for blockages it is at the manifold outlet.The usual method of diagnosis for a RWC engine is to start at one end or the other of the cooling system and find out where the water flow is reduced.

If running off an auxiliary fuel tank solves the fuel problem then the problem is before the fuel pump. If you still have fuel problems while running with the auxiliary tank then the problem is with the fuel pump and\or the carb.

How long has it been since you've had a look at the distributor advance?

Hang in there. You're getting close.

TRUE GRIT

Pretty sure I'm RWC... Don't believe there is anything wrapped on the prop, shes been in a lake the last two years at least, and there isn't really anything in there to wrap.

My Thermostat currently isn't reading at all, maybe that's an indication that it is stuck shut?

Oddly, the smoke is coming off a section that was rusted, so I used WD40 as a cleaning solution - maybe it is just that burning off...

For next weekend, I think I'm going to pop off and clean the carb, then try running it again. If that doesn't work, Ill do the auxiliary tank check. Is it worth changing the filter in the racor if I don't know its history?

Will also order a new impeller as the one I took out seems like its hardened with the impellers in a bent position...

[Mo]

Sounds and looks pretty good to me, I agree with the guys.

Smoke...once it's been running for a while and ensure everything is burned off check around the manifold and hot exhaust...that could take about 30 minutes...otherwise you may have to change the hot exhaust.

Water, mine is about like yours at idle....might not be an issue at all. If impeller hasn't be changed recently by all means change it out anyway. A infra red thermometer is a good idea and you can usually pic one of those up for about $25 on sale.

Neil mentioned fuel system/ carb...fully agree as well. It takes a second to block you carb with crud, and if the engine won't throttle up a carb blockage or sucking air ... among other possible causes those are the two I suspect right away.

[hanleyclifford]

No one ever finally solves the problem of fuel contamination and system blockage. We are never more than a single particle a few thousandths of an inch in diameter from a fuel issue and that is why vigilant fuel filtration and monitoring are so important. The last two experiences (before the carb) fuel should encounter in an Atomic 4 are a 10 micron filter and a fuel pressure gauge. Keep trouble upstream where it is easier to handle. BTW, cleaning polluted fuel and reintroducing it to the system is dodgy IMO.

[ndutton]

1. The PO may have done excellent work and maintenance, maybe not. The only work you can trust is your own. We generally hold PO's - and many so-called professional mechanics - in disdain around here.
2. New tank is the smart move. The ethanol component in gasoline acts much like a solvent and can return tank residue into the mix.
3. Please replace the O-ring seal on the fuel fill cap. It's seldom done and a critical sealing point.
4. Again, with ethanol in the fuel it absorbs water rather than allowing it to separate. My guess, depending on the volume of fuel you had in the tank, is the ethanol absorbed as much water as it could to the point of saturation and the remaining water is what you saw in separation. I wouldn't trust the old fuel to start a campfire, maybe to put it out though . . . .

My best advice is to get much more aggressive in cleaning up the fuel system. The engine sounds sweet when she's running.

edit:

For next weekend, I think I'm going to pop off and clean the carb, then try running it again. If that doesn't work, Ill do the auxiliary tank check

If you run old (read: questionable) fuel through your newly cleaned and rebuilt carb, you'll need to clean it again after. You may want to reconsider the order in which you're trying things to prevent doing the same repairs over and over.

Is it worth changing the filter in the racor if I don't know its history?

Absofreakinglutely. Until you get fresh gas in a clean tank you should have several filters on hand. There's that repeat repair thing again.

[LemonShark2]

1. The PO may have done excellent work and maintenance, maybe not. The only work you can trust is your own. We generally hold PO's - and many so-called professional mechanics - in disdain around here.
2. New tank is the smart move. The ethanol component in gasoline acts much like a solvent and can return tank residue into the mix.
3. Please replace the O-ring seal on the fuel fill cap. It's seldom done and a critical sealing point.
4. Again, with ethanol in the fuel it absorbs water rather than allowing it to separate. My guess, depending on the volume of fuel you had in the tank, is the ethanol absorbed as much water as it could to the point of saturation and the remaining water is what you saw in separation. I wouldn't trust the old fuel to start a campfire, maybe to put it out though . . . .

My best advice is to get much more aggressive in cleaning up the fuel system. The engine sounds sweet when she's running.

edit:
If you run old (read: questionable) fuel through your newly cleaned and rebuilt carb, you'll need to clean it again after. You may want to reconsider the order in which you're trying things to prevent doing the same repairs over and over.
Absofreakinglutely. Until you get fresh gas in a clean tank you should have several filters on hand. There's that repeat repair thing again.

I just ordered a new filter, new impeller, and a bottle of moyer mystery oil.

Do you have any recommendation on types of fuel tanks? My current one is a big hunk of metal, I was thinking about switching to one of the plastic ones.

[ndutton]

Do you have any recommendation on types of fuel tanks? My current one is a big hunk of metal, I was thinking about switching to one of the plastic ones.

When I replace my tank I'll have a hard look at the Moeller cross linked polyethylene tanks. Shawn Stanley has one in his boat and his experience has been favorable.

[edwardc]

..Do you have any recommendation on types of fuel tanks? My current one is a big hunk of metal, I was thinking about switching to one of the plastic ones.

Depends on what type of metal.
If its galvanized steel, then definitely change it. (IMHO)
If its aluminum then maybe, depending on the condition.
If its Monel, then don't change it!

Monel is like the gold standard for fuel tanks. It is a high nickel alloy that is very corrosion resistant. At one time, in the mid-70s, it was very common for fuel tanks, but now it's too expensive for boatbuilders to use.

In appearance, monel is a dull color, somewhat similar to galvanized steel, but with a much smoother finish. Depending on the percentage of copper, it may acquire a slight greenish tint with age. Its is also poorly magnetic. A magnet will stick to it only weakly.

More on Monel here:

https://en.wikipedia.org/wiki/Monel

[LemonShark2]

Depends on what type of metal.
If its galvanized steel, then definitely change it. (IMHO)
If its aluminum then maybe, depending on the condition.
If its Monel, then don't change it!

Monel is like the gold standard for fuel tanks. It is a high nickel alloy that is very corrosion resistant. At one time, in the mid-70s, it was very common for fuel tanks, but now it's too expensive for boatbuilders to use.

In appearance, monel is a dull color, somewhat similar to galvanized steel, but with a much smoother finish. Depending on the percentage of copper, it may acquire a slight greenish tint with age. Its is also poorly magnetic. A magnet will stick to it only weakly.

More on Monel here:
https://en.wikipedia.org/wiki/Monel

Good to know, Ill check on that this weekend. Even in the situation that I keep it, Ill still probably drain the fuel and try and clean it out.

[sastanley]

When I replace my tank I'll have a hard look at the Moeller cross linked polyethylene tanks. Shawn Stanley has one in his boat and his experience has been favorable.

I have been happy with mine.

I agree with the others on fuel. Here is my almost infamous saying around here....topping off a tank that contains 5 gals of bad fuel now gives you a full tank of bad fuel, and fuel system treatments never fix already existing issues.. Neil touched on the issues already, so no need to repeat. You cannot 'fix' bad/water contaminated/yucky ethanol laced fuel..

Burn all the old fuel first, or discard it, so you are dealing with fresh fuel. If you add new fuel filters to the mix, you'll also likely burn through those $$ filter elements that cost far more than the few gallons of bad fuel you are trying to salvage. Don't bother replacing the filters until you are done with the old fuel and are burning fresh.

Glad you got it running, all downhill from here. Do you have a temp gauge? What part of the t-stat is "not working"? Stuck open/closed/filled with gunk, etc?

edit - oh...you asked about the little primer on the mechanical fuel pump...100 is a little excessive, but you might need that many to prime thru a filter,etc. There is a pushrod on the camshaft that moves the pump diaphragm in the pump housing..the handle allows you to actuate the diaphragm from the outside for priming...if the pushrod is in the extended position and keeping the diaphragm from moving, you'll feel no resistance on the handle..you should feel some in one direction of travel when pulling fuel/air (there are a couple little springs inside that provide the resistance if the diaphragm is moving freely.) If you are not feeling resistance, try bumping the motor with the key, or turn the motor it by hand if you have a flywheel crank, to reposition the pushrod and allow the diaphragm to fully articulate with the handle.

[JOHN COOKSON]

Good to know, Ill check on that this weekend. Even in the situation that I keep it, Ill still probably drain the fuel and try and clean it out.

LS2
You're on the right track here. If the fuel is questionable get rid of it. Don't fight with it. As noted additives will not clean up dirty fuel. It what's going on inside the tank that determines engine performance.
Small detail: Marine tanks fill and empty from the top so you won't be able to drain it. What works sometimes is to attach a tube to a stick or dowel with cable ties and leave the tube sticking out from the end of the dowel ~ 2". Then use this apparatus to guide the end of the hose to the lowest corner of the tank while you pump the gas out. Catch some of the fuel in a clear glass jar and hold it up to the sunlight to see how much crud is in it.
If you don't have one already I would strongly suggest a final filter between the fuel pump and carburetor. Available from MMI.

TRUE GRIT