Fuel Injectors

[Wannabe]

Greetings,

I am a long time lurker considering purchase of a new to me boat.* I am a newbie with deisel engines.* The engine survey came back with an elevated fuel level in the oil analysis.* I understand that this probably means the injectors need some cleaning/adjustment.* I need to know how involved and expensive this repair is.* Can you shed some light on it for me?

Thanks for sharing your experience and knowlege.
Wannabe

 

[troy994719]

What kind of engine is it?

 

[Wannabe]

Lehman 120.

 

[troy994719]

American Diesel sells them for about $90 each. You have to remove *the valve cover and remove the rocker arms to replace the injectors.

 

[Daddyo]

Actually you don't remove the valve cover. The injectors are mounted in the side of the head. Replacement is pretty easy as even I have done one. You have to be very careful not to crimp or bend any of the fuel tubing going to the injectors when making the exchange. Fuel in the oil might be coming from the injector pump I believe this is about a $800 rebuild.

 

[Marin]

An elevated fuel level in the oil can also mean a leaking fuel return line.

 

[FF]

The most common cause would be poor compression from lack of use though there are loads of other causes.

Looking at the oil sample log will show how long the problem existed .

My guess is the seller came to the boat , ran the engine at dockside (to "exercise" it) and caused the poor sample readings.

If this was just for the months the boat was for sale , no biggie , change the oil.

IF this was his "technique" to not have to pickle the engine during his off season , plan soon on a rebuild IF the engine smokes with a load , after warmup.

 

[troy994719]

Daddyo wrote:

Actually you don't remove the valve cover. The injectors are mounted in the side of the head. Replacement is pretty easy as even I have done one. You have to be very careful not to crimp or bend any of the fuel tubing going to the injectors when making the exchange. Fuel in the oil might be coming from the injector pump I believe this is about a $800 rebuild.

You do have to remove the valve cover and the rocker arm assembly. Sounds like what you replaced was the injector lines or the connection to the injector. Here is a picture from the service manual that shows the injector and the injector line\connection. I think American diesel has an injector removal tool, I would get a valve cover gasket and the gasket kit for the injector lines. The gasket kit replaces all the rubber fittings that go into the head on the injector lines, thats a good place for an oil leak to develop. This will also give you a chance to adjust the valve lashing, another good thing to check on the Lehman.
Here is a link for the operators manual in case you would like a free copy.

http://www.gbwoodies.com/OwnersManuals/Lehman/Lehman%20Append%20A-Parts/index.htm


*

 

[Wannabe]

All,

Thanks for your input.* I am sure this is just the first of many questions as we feel our way through this.

Regards,
Wannabe

 

[C lectric]

I'm sure this is too late to be of help but the lift pump on the side of the engine can also leak fuel into the crankcase.

 

[rwidman]

Since several possible causes have been posted, and most require considerable expertise and cost, it might be a good idea to have a competent, experienced diesel mechanic actually examine and repair the engine. Or - there might not be anything wrong with it.