Perkins 4108 Fuel Problem

[perchance]

Try adding more fuel to the tank. There may be a pinhole further up the pickup tube in the tank. Adding more fuel will verify this.

[NoAgenda]

Hey y'all. New member here. Also have a Perkins 4-108. with intermitten stalling, I found a bad seal in the Raycor was allowing air into the pump, causing at first skipping, then an all out stall. check that the top of the filter housing is properly sealed, that or check the gasket. Any irregularities may be allowing air in. Good Luck, and hello to all

[Jim Cate]

I had a similar problem some years ago with a new alloy diesel tank. Turns out that there was indeed a pinhole in the pickup tube where it was welded as it entered the top to the tank. A bit of Permatex #1 gasket glue rubbed into the outside fillet of the weld cured it forever. You might have a very close look at that area if your construction is similar.

Cheers

Jim

[Wainui]

Finally had time to go on a long motor after replacing the lift pump and changing the oil. I am leaving the electric fuel pump on while motoring.
After 3 hours of motoring at about 2,300rpm the oil pressure had dropped from just over 40lbs down to 25lbs. the water temp was 185/190 on a hot day. The engine was blowing some white smoke that would hang until about 12' from the boat. Apon arriving at anchorage I checked the oil level which was 1 and a 1/2 inch higher than when I started. I am thinking it may now be the injection pump leaking fuel into the sump? I have sent some oil out to be checked. Can the Injection pump leak into the engine?
Now I am off to do the Transpac and will have to deal with this when I get back *****perkins
regards
Mark

[Astrid]

The engine was blowing some white smoke that would hang until about 12' from the boat. Apon arriving at anchorage I checked the oil level which was 1 and a 1/2 inch higher than when I started.

That almost sounds like a blown head gasket when coupled with a higher than expected oil level.

[Wainui]

Would a blown head gasket let water into the engine and then the oil would go cloudy?

[Astrid]

Yes it could, and you would get white exhaust, perhaps intermittently or continuously that would linger for a bit until the steam condensed out. Run a compression test on each cylinder.

[JulianGullsway]

I'am no expert, but I had water coming back to the engine and it turned out to be the water cooled prop shaft which worked under high pressure to cool it, the pressure was so great it was some how forcing water back into the block, yes the oil will turn cloudy and will spew out of every where if your getting a mass of water in the block, I disconnected it re positioned the water blocker (It was on the same height as the heat ex changer ) I also changed the head Gasket for good measure, But I doubt you would have got as far as you did under the same instance, might sound nasty but taste the oil mixture, can you taste salt or diesel, I had a plethora of problems with my 4108 and was very close to replacing the whole lot, including a constant cutting out which turned out to be a faulty rubber seal on one of the fuel filters, it can seem so bloody frustrating, but stick with it you will eventually find the fault, Good luck !!!!

[Wainui]

Changed the lift pump which did not cure the problem. We looked further and found the IP seal was leaking and that the raw water pump bearing was also leaking into the engine. The leak hole in the RW pump was blocked and as my engine is reverse mounted, it was not easily seem.
The engine was redone about 150 hours ago but not the IP. This engine has more ways to fill up with fluid than I realised. I quess the IP seal was letting air back into the return line to slowly fill the filter with air and stall the engine. I feel like Sherlock Holmes after getting to the bottom of this problem
Thanks for all the advice.
Mark