Beat To Death Thread 4.108 Bleeding or?

[forsailbyowner]

Im at my wits end with this diesel. I left an anchorage in the glades and the engine died. i sailed back to tampa and pulled into a slip towing with my 4 hp dinghy. (solo). That was two months ago. I found the fuel pipe between the filter housing and injection pump had rusted out and was leaking. My first thought was a quick fix. I took the lines off (ones running from filter to injection pump) cut the ends off leaving enough to clamp hose to. before reattaching to the injection pump i ran a half gallon of diesel thru in case I had rubber from inserting fittings on the hose. I then bled a copious excessive amount of fuel through head locking screw and the air vent on the top of the governor. It has an electric pump inline so its just a matter of opening bleeding points and letting it flow. I was catching the diesel and ran at least a quart through each point. it would then start instantly, run for exactly 5 seconds then die. Wait for about 10 seconds and do the same thing. I bled, over and over till I figured maybe rust had gotten into the injection pump.

Phase two. I traded a bimini build for a perkins 4.107 in parts. The two lines i needed were shot but the injector lines were in much better shape than mine so... I replaced the injection pump, injection lines, and ran 1/4" copper lines with compression fittings in place of the rubber hoses. This seemed to work well. Again I ran copious fuel thru to flush lines before connecting to pump. Did the same bleeding thing running a bunch thru the same points except one additional point i picked up in the injection pump manual which says to bleed at the blocked off passage at the filter housing. After I figured out the stop lever runs backward from the one I had I have good fuel squirting out of the lines while cranking. After final bleeding, It cranks right up, runs for 5 seconds then dies AAAAARGH!!!!!!!!

One thing I noticed which i dont know if is normal is... I get a strong flow out of head locking screw, it will shoot 6" or so out of the vent screw i get steady drips but nowhere near the flow of the head locking screw. Normal??? Didnt think too much of it after looking at the pump diagram and seeing possible flow restrictions from metering valve and small passages.

Anybody can shed some light here? Im tracking down a diesel mechanic who needed canvas work and gonna try to work out some kind of barter for his services. He charges $85 hr and I cant afford many of those (hrs)
Thanks for any replies.

I should add, racor filter, engine filter, replaced. lines gone over from end to end and less than 2 yrs old. Fuel flows unimpeded to injector pump. pumps quart in no time.

[Hoofsmit]

Pump timing? If you changed the pump ?
The only other things I can think of is injectors are worth a service/ clean and are you sure the lift pump is UPTO scratch

[Loredo]

In your bleeding procedure you don't mention craking open the injector lines @ the head. You DID bleed also the injector lines, right?

[a64pilot]

Will it continue to run if you leave the electric pump running? Sounds like a lift pump issue to me. I do not think injector pump as same problem existed prior to changing it.

[model 10]

Sounds like air is getting in between the tank and the lift pump. It only takes a very small bubble. At only 5 sec of run time, the air leak must be close to the pump. You sure the lift pump is working? On our 107, the electric pump will not keep the engine running nor does it help with bleeding. For bleeding, we need to use the manual lever on the lift pump. If the lift pump diaphragm is shot it can leak air.

[forsailbyowner]

yep bled the lines with them disconnected to check the volume, then connected and cracked the two recommended. It fired right up, for 5 seconds. Im on a lead now. I talked to Jason at dieselitems.com in alabama. He was very helpful. He said if it did the same thing with two pumps its time to look elsewhere. He said from what it sounds its a plumbing problem either constriction in the inlet side or BLOCKAGE IN THE RETURN. I hadnt thought of that at all. Upon removing the filter housing there was an old seal smashed into the port in the return. Im in the process of cleaning it up and giving a cosmetic go over before reinstalling.

Lift pump is 1 yr old and pumps good.

One thing I found in the cav dpa instruction manual that I hadnt seen anywhere in other bleeding instructions is. On filter housings with 4 ports the blocked off port MUST be bled regardless of there being a bleeding screw on the top of the housing. Thats the only place that Ive seen this mentioned and Ive seen a lot of different bleeding instructions in various places.

I will give the results of how things go after reinstalling the filter housing and going thru the bleeding process again.

[forsailbyowner]

Originally Posted by Hoofsmit

Pump timing? If you changed the pump ?
The only other things I can think of is injectors are worth a service/ clean and are you sure the lift pump is UPTO scratch

I followed the cav pump instruction manual for the install. using the stamped marks for timing. they were in identical locations on both pumps. One thing that did throw me for a loop for a while. On one pump the fuel shutoff is pushed forward to run, on the other its pulled back.

Gonna test function of year old lift pump while the filter housing is out just to make sure.

[forsailbyowner]

Originally Posted by Guy

Sounds like air is getting in between the tank and the lift pump. It only takes a very small bubble. At only 5 sec of run time, the air leak must be close to the pump. You sure the lift pump is working? On our 107, the electric pump will not keep the engine running nor does it help with bleeding. For bleeding, we need to use the manual lever on the lift pump. If the lift pump diaphragm is shot it can leak air.

I wonder whats up with your electric pump? As mentioned mine shoots diesel about 6" out of the head locking screw and as mentioned dribbles out of the vent screw. Ive had this boat for 10 yrs and have had bled it before at least annually when changing filters. Last time before this was a real pita Im thinking the piece in the port was there then and blocked off the passage completely when i was changing out the line. The lines are new and dont leak when the 5or6 lbs of fuel pressure are present from the electric pump.

[Pirate999]

You beat me to it... I was going to suggest a blockage somewhere else, even the return line. I'd remove all the lines and clean. Rust or corrosion may have cause a blockage somewhere.

Worse case is it's your injector pump.... Doesn't take much to ruin them.

[Phantoms]

Just a quick thought, but how about clogged tank vent? Try opening fuel fill when it shuts off and see if you hear an in-rush of air. See if it will run longer with the tank fill open.

[forsailbyowner]

WOOOOO HOOOOO!!!!!!!!!!!!! Happy dances and celebrations here!!! cleared the return line, bled and she started up instantly. Id be gone today if I didnt have 3 canvas jobs with contracts signed and deposits received. I will be a stitching fool this next two weeks. Thanks everybody.

[bletso]

We had a similar problem last week. The manual shut off wasn't fully disengaging.

[ontherocks83]

Originally Posted by forsailbyowner

WOOOOO HOOOOO!!!!!!!!!!!!! Happy dances and celebrations here!!! cleared the return line, bled and she started up instantly. Id be gone today if I didnt have 3 canvas jobs with contracts signed and deposits received. I will be a stitching fool this next two weeks. Thanks everybody.

Awesome!! Good to hear what the fix was. Thanks for sharing

[forsailbyowner]

Just a follow up to add a few things I learned. I looked far and wide for the lines running between the fuel filter housing and injection pump. Not available. When i contacted partsforengines.com they told me they replace them with 1/4" copper tubing and compression fittings. Total cost was $8 at ace hardware. These lines are thinwall and nowhere near as thick as the injection pipes, so if you see pitting BEWARE!!

For an injection pump rebuild, Dieselitems.com was $200 less that any estimates I got in the tampa bay area and offered free injector service with a pump rebuild, this cost $65 per injector locally. The owner there was the one who gave me the tip to check plumbing going to and from the pump and saved my day.

[Hoofsmit]

Thanks for the heads up on the fix, another one to put in the fault diagnostic little black book