Can't keep my engine running

[bkrizmanic]

I have a 32 hp Universal Diesel model 5432, I have been having problems with it for the last week, it started when the engine died in some rough weather, I felt it was fuel starvation and thought maybe I stirred up a bunch of junk in the tank, Changed both filters as well as cleaned the screen on the electric fuel pump, the fuel looks clean, no visible water but it still seems like I have the same fuel starvation. Any idea's?

[Sandero]

air in the fuel lines.. or maybe a small breach which is letting air in? Try bleeding the fuel lines.

[damir s]

Maybe is dirt on suction side in the tank try to blowback with air and later clean fuel tank from dirt

[cabo_sailor]

I have had both happen. Clogged pickup tube, needed compressed air to clear. And air leak. Went back and tightened every hose clamp I could find on the fuel system. Perhaps bleeding the injectors? Might also be bad fuel pump. I kind of doubt a bad injector. It would run rough but run. Gods forbid something with the injector pump!

How many hours on engine? Any recent service?

The rough weather part would suggest some crud picked up in tank.

[DeepFrz]

Some pickup tubes have a wire mesh/screen on the bottom. If yours does have one then take it off and dispose of it.

[a64pilot]

On delivery when I bought my boat engine would die of fuel starvation, filters etc. clean as could be, I thought lift pump, but turned out to be some junk in the dip tube, stuff had the consistency of tofu and none of it ever made it to the filter, just clogged the pick up tube.

[bkrizmanic]

Thanks for all the input, I'll try the pick up tube next...Thanks

[Cheechako]

Did you engine speed up and surge before dying? That's what mine usually did if starved for fuel.

[bkrizmanic]

Originally Posted by Cheechako

Did you engine speed up and surge before dying? That's what mine usually did if starved for fuel.

it did not, just started running rough and died.

I check out the pick up tube, the screen was at the top of the tube,(actually the tube does not come out of the tank)in the fitting and had a lot of something in it including what looked like insulation from a electrical wire...not sure where that owuld have come from.
I guess the real question left is if the tank itself needs to be cleaned out. I am going to run it for a couple of days and pull the screen again to see.

Thanks for all the help

[DeepFrz]

Take that screen right out of there and throw it....
The filters should be filtering that stuff out not some itsy bitsy screen.

engine would die of fuel starvation, filters etc. clean as could be, I thought lift pump, but turned out to be some junk in the dip tube, stuff had the consistency of tofu and none of it ever made it to the filter, just clogged the pick up tube.

Yep, been there done that. Not a lot of fun in a seaway.

By the way I have found out that by putting a few drops of bleach on the gunk you can tell if its biological or tar precipitates. If it turns white its biological growth.

[Lepke]

If all your problems started with rough water the problem is most likely crud from the bottom of the fuel tank being compacted at some point in the fuel lines/system. As DeepFrz said, a common problem is a screen in the tank becoming fouled. But I have also seen screens behind fittings where fuel enters the filter housing, injector pump, lift pump, etc.
If you can't get compressed air, you could use an electric fuel pump to reverse flow fuel thru the pickup tube from a can of diesel. If your tank has a inspection port or fuel sending unit, you may be able to get a look inside.

[Russ]

Just been through this. It IS an air leak and they are hard to find. I got excellent advice and here is what to do.

Wrap EVERY joint i.e. Flare fittings or whatever with a small piece of paper towel and run the engine. Then look for the red diesel stains on the paper. You may need to do this backwards and PUSH the fuel through the system. To do this you need to hook up a fuel grade pump to he INPUT of the system i.e. where the fuel line attaches to the fuel tank and pump for an hour or two then again look for leaks at ever joint. I personally would NOT use teflon fuel grade tape but a fuel approved paste and use flare nut wrenches. Good Luck Russ

[GrahamHO]

An air leak in a primary fuel filter on the suction side can cause your problem.
Change the primary filter element and lightly grease the new O rings that are supplied with the element before you fit them. Often an old O ring in a groove on the filter body can be overlooked. It's likely an air leak somewhere on the suction side of the lift pump but can be gunge in the bottom of your tank.

[Charlie]

To check for an air leak it is a good idea to install a piece of clear hose in the fuel delivery system. If there is a leak you will see bubbles in the clear hose. That does not test for leaks beyond the delivery system. I take this as a necessary thing to do on older boats: 1) Cut holes in each baffled section of the tank, 2) empty the tank, 3) install access plates (I have used these and really like them), 4) use a scraper and clean the sides off of the scudge, 4) use a scotch brite pad and windex to get the tank really clean and 5) seal the ports. This will ensure clean fuel in the tank. On one boat I also changed all of the fittings and the fuel lines. On the other I replaced the filters after running it at the dock for a couple of hours. I like Russ' tip about the paper towels in checking for leaks but am not sure whether or not they would detect an air leak. I found one once that wasn't leaking fuel but allowing in air. I found it because I felt the hose clamp and felt that the hose had been cut by the clamp. Probably a fuel starvation or an air leak. Hard to tell which one.

[SkiprJohn]

Originally Posted by bkrizmanic

it did not, just started running rough and died.

I check out the pick up tube, the screen was at the top of the tube,(actually the tube does not come out of the tank)in the fitting and had a lot of something in it including what looked like insulation from a electrical wire...not sure where that owuld have come from.
I guess the real question left is if the tank itself needs to be cleaned out. I am going to run it for a couple of days and pull the screen again to see.

Thanks for all the help

This answered my question. The engine runs but runs rough? The engine dies after running good for awhile?

I think that if there is air in the system it will not start and run. That's been my experience.

I think you have some gunk in the pickup tube at the tank or along that tube somewhere before it gets to your filters. There is a good way of checking this by putting some clean diesel fuel in a container and tapping it into your fuel line. I use an old plastic gas can with some extra fuel hose. If the engine runs smooth without a problem then you've isolated the problem area.

Just a thought. Good luck in your troubleshooting.