Our Engine Died! Whats up?

[Bob Robeson]

We have a 1986 Catalina 36 with a Universel M25, 21 HP Diesel engine.We went out for a sail and as luck would have it the wind did not come up. So after sitting there with our sails up for over an hour we decided to go back to port.We started our enging, and started for home when the engine started to slow down, not react to thottle, and sputters to a stop after only running a minute or so. Trying to restart, it would start, and then sputter to a stop.I changed fuel filters (did not bleed anything) and turned on the eletric fuel pump until it slowed to its normal click, click, click. I tried to restart and it would restart and sputter to a stop, soon it would only fire, acting like it would start, but never quite starting, after multile atempts, I gave up as the wind came up and I sailed back to port.I do have a Racor water seportaor filter, before the stock engine fuel filter.It has a new fuel tank from Catalina and I have run about 20 galones of fuel through it. Since it died slowly and it did restart, I feel the engine may be OK, but that I may have a fuel problem.Any idea?ThanksBobC-36

 

[Dave Ullrich]

BLEED IT

First I would bleed the engine to make sure you are getting anice fuel flow.

 

[Stevec]

I would check the bottom of the fuel pickup tube

in your fuel tank. Sounds like the engine is being fuel starved. Unless your engine is a 'self-bleeder' (which I don't think yours is), if an engine has air in the fuel lines, it will not fire at all. Fuel starvation allows an engine to start, run for a while and quit. But it will attempt to fire up again if you try to restart it. I have a Yanmar and the pickup tube has a small screen at the bottom to prevent gunk from being sucked up from the tank. If you have one there, just remove it. The gunk has probably clogged the screen preventing fuel from being drawn up. This could be the cause since someone has just messed with your tank. We've kicked this one around quite a lot on these forums...

 

[Patrick Ewing]

Could be exhaust riser blockage

See if the riser is plugged with soot and rust by removing the hose and then see if the riser is blocked by sticking something into it. It may take a hammer and chisel to clean it out - ours did. Several mechanics couldn't figure it out and we changed filters, bled lines, removed and checked injectors and pump, etc. several times. I now check this item annually.

 

[Bob Robeson]

Its fixed, but dont know why!

1)I changed the water sep and main fuel filler. 2)Checked all fuel line connections, there was a very small leak at the "T" fitting to the heater.3)Removed and checked pickup tube (no strainer)4) Bleed the intire system.Stared engine and it ran for about 2 minutes before sputtering and dying.1)I removed fuel cap for ventilation!2) removed and clean the fuel shut off valve.3) rebleed the system. It ran fine so we went out and it sputtered and died. This time the fule pump was running fast.4) I sailed to a fuel doc and tried to fill up. Weird things happened.A) even though I was low on fuel it would only pump fuel out the vent. B) I closed and opened and fuel valve and suddenly I could fuel in the tank.5) I rebleed the fuel system and wowla, it runs fine now.Conclution:I had some kiind of air lock, fuel blockage that I can not fine and it finaly cleared itself. Since I do not know what the fix was, I do not know what the problem is, it may happen again.But hey, I know how to bleed the system, change fuel filters and water strainers, and how to check the fuel return and just how my fuel system works.Big funThanks for all your input and suggestions.BobC-36#586