351W Died then won't run right

[ashedd]

I have an old Palmer Thermo Electron 351W that has been running great. Then one night around 12/23 it start surging and stalled. It kinda started again, with difficulty, then died again never to restart.

The next day it started fine. I let it warm up and it surged again and died after about ten mins. So I replaced the fuel filter, judging by the tools required to remove I would say it was several years old. I also replaced the mechanical fuel pump as it looked original.

I got it started and warmed up. Went out for a water test and did the same after about 20 mins. Limped home with one engine hitting the dock :/

I replaced the coil. No start. I verified spark with no start. Pulled a plug and it's caked with carbon. Scraped it of and got blue spark from it. That was number 8. I get spark on number 1 via timing light. Voltages are good at ballast resistor. Everything under the distributor looks fine.

I took the Holley 4160 for a rebuild from a carb shop. He said it had some issues but it was good to go. I installed it and can't get it started. Previously it would basically start the next day. I drained fuel from the filter and it looked ok to me. I got fuel from the fuel pump while cranking. Still no start. It always tries to start when I try to start it. It'll stumble and die with a carb backfire.

It'll run ok with starting fluid. My next step is new plugs and maybe try a different fuel source.

When it ran it runs good until it surges and dies. I've never checked compression.

Any ideas?

 

[ashedd]

More info:

Carb guy said the secondary diagram was damaged. That might explain my 2500 RPM WOT. The spark arrestor was clogged, I had him clean it. And once when it wouldn't start I pulled the pcv hose off and it started fine. Hook it back up and it wouldn't start. That trick didn't last long however.

 

[alldodge]

I runs fine on either but will not start with gas, this tells me it's not getting gas. With it running 10 minutes and then dying leans me to where the pump is having trouble sucking fuel up. So you need to go thru the fuel supply system.

On top of the fuel tank there should be a barbed fitting which has a spring loaded ball inside it. This is called an anti-siphon valve. This ball can stick and restrict fuel. Remove the valve and clean with some carb cleaner, or just replace it if in doubt.

If the pick up tube can be removed, do so and clean the screen. If it cannot be removed blow some low pressure air back thru it.

Check the fuel tank vent line to make sure something like mud dobbers have not filled the opening.

Replace the plugs

Install a fuel pressure gauge between the carb and fuel pump. Pressure should read 4 to 7 psi

 

[ashedd]

I'll try your suggestions. It's worth noting that it won't start at all now, except for maybe three seconds. After that initial start it won't do it again. I'll check the vent line again but I just checked it a month ago after discovering the port side vent clogged. I'll look for a check valve on the tank but I'm not too optimistic it has one. The tanks are pretty basic from 1957. But I'm sure there's a screen. Might be worth mentioning that there is about ten feet of couple fuel line

 

[alldodge]

Now it won't hit with starting fluid?

 

[ashedd]

Oh no it'll start with starting fluid and even run good for about ten seconds if I spray enough. It just won't start off the gas like it used to. Not since the water test.

 

[ashedd]

It'll still start and run for about 2 - 3 seconds first time I start it. When I get there today it will likely start right up for those few seconds then not start again without fluid.

 

[ashedd]

Here is the spark plug I removed. It was so fouled I could barely see a gap. I scraped this one with a screwdriver and cleaned out the gap. Normally I wouldn't suspect the plugs since it runs on starting fluid but these are really fouled.

 

[alldodge]

From the looks of that one plug and with the other issues we discussed in other threads, I'm thinking it may be time to rebuild or replace the motor. The other one was replaced for probably similar issues. If you replace all the plugs, your getting spark and it will not continue to run its either old gas or no gas

 

[ashedd]

From the looks of that one plug and with the other issues we discussed in other threads, I'm thinking it may be time to rebuild or replace the motor. The other one was replaced for probably similar issues. If you replace all the plugs, your getting spark and it will not continue to run its either old gas or no gas

I really don't want to replace this motor anytime soon lol. It's a Ford so basically nothing would transfer to a replacement 350. If I replacing the motor I would want it to match the crusader 350 on the left side. Think I've mentioned several times, but that 2001 crusader looks new. The oil is even honey brown! It would be silly to rebuild this Ford, even though it maybe cheaper. I think I've spent $900 so far on this motor if I include all the stupid cooling hose I bought. I'm also not real sure how to physically remove the engine since it's under the floor in the "pilot" house. In 2016 I spent as much on boats than I would on an airplane... Think I'd rather have an airplane at this point.

 

[alldodge]

I really don't want to replace this motor anytime soon lol. It's a Ford so basically nothing would transfer to a replacement 350. If I replacing the motor I would want it to match the crusader 350 on the left side. Think I've mentioned several times, but that 2001 crusader looks new. The oil is even honey brown! It would be silly to rebuild this Ford, even though it maybe cheaper. I think I've spent $900 so far on this motor if I include all the stupid cooling hose I bought. I'm also not real sure how to physically remove the engine since it's under the floor in the "pilot" house. In 2016 I spent as much on boats than I would on an airplane... Think I'd rather have an airplane at this point.

I hear you, but the 351 appears to be pumping oil. Do remember the other was a 350, just mentioned the rebuild because its always an option. Do agree going with the 350 would be the best choice.

As for the engine removal, don't know how, but the Crusader tells us it was done once. If you could post some over all pics we might get some ideas

 

[ashedd]

Replaced plugs. All looked clean and dry. Number 3 was fouled like the previous one from cylinder 5(originally thought it was 8). It was fouled enough to completely fill the gap. It's been running great for ten mins now. No carb adjustments yet. Idling at 1000, 650 in gear. Carb guy says the idle mixture is set a little rich and to turn both screws in 1/8 of a turn at a time up RPM peaks them adjust idle speed back down.

The motor has valve noise that goes away after it warms up. I'm not sure if it's always been there or came after I changed the oil when I was replacing cooling hoses. This is really the first time I've run the motor with all the covers/floors out.

If it's "fixed" then I'll hit it heavy with seafoam and hope that the rings are just gummed up from not being used. The previous owner had the boat ten years and took it out maybe five times a season. But he did start the motors every month at least.

 

[ashedd]

Can't see timing marks so I'll have to try and clean them off. All I can tell is the timing is about 1/4" after the line.

 

[alldodge]

Carb adjustment sounds good, might need to turn them back out and 1/8 once rpm is set

Seafoam is snake oil IMO but use if you want to

Valve noise going away once it warms up lets me know the lifters are collapsing. So once the engine is under a heavier load some of this could be happening still.

Another one of my opinions, but even if it starts running better, I don't think its fixed. It may last long enough before something else happens, just roll the dice

 

[ashedd]

Water test went well. Got 20 knots out of a 40' motor yacht, not too bad. Got the timing set. I fixed the stuck advance weights. Fiddled with the idle mixture but need to redo it. Went 8nm to my favorite bay at 12 knots and dropped anchor. Think I'll stay the night if my propane heater holds out. I'll do some more high speed runs to try and loosen up any stuck rings and maybe burn off some carbon. Hate to imagine what the fuel burn is but I've got 100 gallons on board.