Jump to content

4890 case injection pump timing

Recommended Posts

Our 4890 case has been slowly running a little less strong, but doing its job. Son used it all day Thursday and ran fine, but Friday morning it wanted to miss and smoke/ pop out the exhaust. We thought injector was stuck, as fuel was dripping from exhaust manifold joint at back of engine. Temp gauge showed #6 only running about 150 degrees. Pulled #6 injector and it seems to hold pressure and pop around 23-2400 psi with a good spray pattern. Yesterday put it back together and it sounds worse, really popping out the straight pipe and smoking. Now #1 only 150 degrees exhaust and fuel dripping from front manifold joint, as well as not hitting on # 6. Dont have a manual for this machine. Does anyone have valve specs and info on how to time injection pump? The pump had a lovejoy type coupler that drives it. I pulled top cover and found years of dirt grease, etc in there. During clean out I found a washer and nut for pump side of coupler. Other bolt is tight but possibly it has slipped inj timing? Any info or suggestions would be appreciated. New fuel filters in last 30 hrs and I pulled return line at pump and it has excellent return flow and hose to tank is clear. It makes no harsh mechanical noise and has little to no blow by. Thanks, Robert 

Link to post
Share on other sites

Yup, injection pump timing was terribly retarded. Jr found timing procedure online somewhere and got it set back where it belongs. Runs like it should now

  • Like 1
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...