[4bt4me]

A while back my Injector pump lost the frount seal and dida thourough thinning of my oil with diesel fuel, but before I knew that I just thought it was the lift pump so that got replaced. I was very busy with work at the time so our tractor mechanic replaced the seal and I had him do the 366 gov spring too... I finished puting the truck back together and when I started it it wouldn't idle, It was wayyyyy too low, so he had to redo something with the throttle shaft ???. After it was done I drove it home and it was gutless, it had no power after half throttle at all, and he only had it set to rev to 2800rpm with the high rev screw... What I'm also lost at is he said the only timing adjustment is inside the pump not by clocking it towards the block, which is different than anything I've read. So I'm curious what he did because i had lost some serious power at this point... Well I decided to take it into my own hands, so I took the AFC diaphram out clocked the starwheel a 1/4 turn, rotated the diaphram to the richest point, turned on the power screw 1.5 turns, and also let it have more revs. I went out for a ride and it was better maybe close to what it was before the mechanic messed with it. Well I then turned the power screw all the way to the metal collar, and did 2 turns on the smoke screw went for a ride and it was good, I had smoke up until about 1300rpms then it cleared up, and power was nice, I turned back the smoke screw until I just had a haze.

Still all along there is a big difference if I give full throttle it actually loses power as opposed to half throttle, it's really starting to bug me... Any insight on the situation? HELP

 

[Carl Donica]

You need to take your pump to someone that really knows the VE pump so they can find and fix whatever your "mechanic" did. Everything you did after will be partial wasted because of what he did. This is one reason I do ALL my own tuning on this engine, I know exactly whats been done and how to undo if need be. If I dont know, I study until I do before I touch anything.
Carl

 

[BobS]

I agree with Carl. You now have too many variables involved. There may be something that is not put back in the right place. Having to re index the throttle shaft usually indicates a certain amount of unfamiliarity with a Bosch rotary pump. The only other things left to try is advancing the pump timing by rotating the top of the pump slightly toward the head and resetting the high idle screw.

 

[CrewCab59]

Hard to say but sounds like he got the throttle shaft turned and even if he did install the 366 spring he turned the the shaft / lever. So when will happen is the engine has no power under load.

1.remove your throttle springs and try to adjust to get the throttle back,if that doesn't work .

2.At this point the top section of the pump has to come back apart.

I did the same thing my self years ago.

Next time do it your self ,take your time and you'll be fine.

CrewCab59

 

[sdstriper]

The guy has the throttle lever indexed wrong or off I should say. I would try it before you take it in to a pump shop. Link over to Den's 3200rpm Gov' spring write up and look at the page with the mention of marking the indexing. When that lever comes off the shaft you can turn the shaft in the direction that will put tension on the spring inside. You do this by hand and try to leave the shaft right at the point of being taught at the spring, then re-install the throttle lever on the shaft making sure you do not let the shaft/spring go slack while doing it.

Good Luck! I had a guy "helping" me once who removed the throttle lever from the shaft and didn't know a thing about the indexing, never even looked at it. It took some tinkering to get it right. It would start and idle but when you throttled up the engine would kill. I got it though and it performed better than previously so I'll call that good enough...

 

[mooktank]

Also,

If your idle is low, use the full fuel screw to turn it up as long as it doesn't run away. It's a good time.

 

[sdstriper]

Or turn up the low idle screw... cussing will be involved.

 

[4bt4me]

He redid the the throttle and it idle's fine now, something else just seems off... Tearing deep into the pump seems a bit overwhelming, as I've never done it before.