2H diesel problem

[oldlep]

Hi everyone ,i have a issue with my 75 troopy it has a rebored turbo 2h with 25000 km recently it lost power and has a rough idle and chugs grayish white smoke i immediately checked fuel filter noticed it had become very dirty so i replaced the filter with a new one but no difference i have cracked the injectors and noticed all lower the rpm except no4 there is no noticeable difference in rpm could this be a blocked injector or a pump problem or somthing else

 

[Tapage]

First be sure you are not getting any air on the lines .. 2H works poorly with air on the lines .. even small amount.

To isolate #4 injector vs pump, swap injectors ..

Edit: feed your IP directly from fresh tank of diesel and see how it behave

 

[ozcrusier]

Good idea to swap injectors to see how it behaves also check valve clearance on number four if this looks OK then pull the injectors and comp test engine.

 

[oldlep]

Ok done a co2 test it was negative to gasses in the coolant i cracked injectors again noticed #3 and #4 dont lower rmp so i suspect there is a leak between 3 and 4 causing low comp and unburned fuel resulting in rough idle and white smoke

 

[ozcrusier]

Did you re-torque the head gasket after a few thousand K ? I've been advised to do so with my 12ht EA kit.
I found with blown head gaskets between cylinders you will hear the cylinders leaking back through the air box as the inlet valve may be open causing back presser.