Fuel in oil LDS4651A

[Recht71]

Thought I would share what I found what the problem was. I bought a LDS engine in a crate this spring, I got it to my shop opened it up. Had tags on it and paper work said rebuilt in 1/87 decommsioned 8/88. When I had the pan off I checked the bearings, all good it was a rebuild. Got the engine in started, ran great. The first parade in May about a 60 mile total run, ran great lots of power. Stop at the VFW fluid pouring out the front seal. It was fuel & oil mix. All the things I read and learned from this site lead to Oil rings in the head of the pump where the lines go in. I pulled the radiator took the plate off where the gear is that drives the pump. At this time I was still trying to fine where all this fuel was getting in to the oil. Started it up fore sure fuel was coming right there from behind the gear. I bought the seal kit from Memphis Truck 100.00, gaskets and o rings. I had never worked on an injection pump before, got the diagram on line. What I found when taking it apart very carefully. 2 screws to remove the cover where the cable hooks to the stop. You pull to stop the engine. There's an u shape bracket a shaft that goes into the injector head. The 2 screws that hold that shaft in place were wired like they do everything, the screws weren't even turned in 1/4 of the way. Anyways there's an o ring there size of a pencil eraser. Strange but that’s what the cause was the o ring was pushed out. Who ever rebuilt it didn't tighten those screws. I did replace the other seal but they all looked fine. The sad thing was I could of fixed it with out taking the pump off. So if you’re getting fuel in your oil check this first. Maybe you'll be lucky. I hope I explained it ok

 

[gimpyrobb]

I could understand it, and I'm an idiot. Thanks for the heads up!

 

[SixSpeed]

Must have had a serious brain fart there...that was supposed to go in the Florida Rally thread. LOL. I'll delete it...

 

[area52]

Good write up on that leak cause/repair.

I have to get my LDS fired up this spring.

 

[Billy Bobbed]

Thats whats nice about this site.You have a problem and you fix it, let us know.A year down the road I might have the same problem. Im going to remember this thread.

 

[Westex]

That is a great piece of info. I was not so lucky. I was making oil and first bypassed the fdc, dumped the oil, then only to discover that it was the injector pump itself leaking. Had to have it rebuilt at a LARGE expense, but the silver lining to the cloud was they pop tested the injectors, and turned them up to the high end of spec. Drove it home from San Antonio this past weekend and aside from the check I had to write, loved the way it drove. Point of all of this is that an injector pop test and adjustment can give you alot of power. But glad to know about the possible leak at the kill pull.

 

[DaveP]

thanks for taking the time to do the write up.

 

[Keith_J]

That is the control collar positioning mechanism. And yes, the little o-ring there is very important since there is fuel at ~50 PSI behind it. Any leak will dump to the IP sump which drains to the crankcase.

Were the safety wires installed correctly? It should be impossible to loosen the screws.

 

[baxter]

Great info, I didnt know you could adjust the injectors how is this done. I have turned up my fuel what is the difference.

 

[RangerDave]

Thank You for reviving an old memory for me!!! This exact problem happened to me and in a quest to find out how to solve my problem, I found this site and all the answers I needed!!! (although searching through endless nonsense to find what you need is a chore , but that was about 4 years agoish...

I thought I took a picture of the "o" ring that burst on mine, and if I can find it I will post it... I was prepared for the worst, but dove in and replaced the 2 large "o" rings on the hydraulic head while I was at it.... One of my screws had loosened as well, even being wired closed. I surmised that sitting for a few years with no fuel might have dried up the small "o" ring to the point that it moved around too much under the plate and finally burst sideways. The crease in the "o" ring was pretty obvious at the time, but all the same, I was still suspect of the other "o" rings/seals that might also be leaking... No fuel in the oil since!!!!

PS: No picture - Sorry

 

[Recht71]

Kieth The wire was on , to be exact the left screw was finger tight and the right one was in a few threads. Seeing the
short time from rebuild to being decommsioned it was put together that way. Might of been a friday !!!! .Thanks for the
proper name and psi info

 

[reloader64]

Westex, where did you have your injectors tested, and how much did it cost?

Thanks,
Scott

 

[wsucougarx]

A quick question to those who had the oil dilution problem. Did your crankcase oil smell like diesel?

 

[Floridianson]

Great info, I didnt know you could adjust the injectors how is this done. I have turned up my fuel what is the difference.

The differance is you can't do them at home and there are two types out there. One you reshim to increase spring pressure the outher adjustable in the injector it's self with threads.

 

[Hay Man]

A quick question to those who had the oil dilution problem. Did your crankcase oil smell like diesel?

I'm currently dealing with this situation and my oil was very thin and smelled like diesel. In fact, everything smelled like diesel when the oil started pouring out of every engine orifice.

 

[rizzo]

I just had this problem after I changed the o rings on my Hydro head. The lower oring was the wrong size. I am hoping that it is fixed now, but wont know until I drive it some more.

 

[rizzo]

I found this using the search function. I had to go back about 6-7 pages, but I found it.