Thread: fuel pump issues... remote assistance?

Originally Posted by Bush65

The pump on my 4BD1-T had 9.5 mm plungers, but they are being changed to 10.5 mm using elements for an Isuzu 4HG1-T pump (Ident. No 101401-7452).

Your engine was export spec? From a truck sold new in Aussie?

My JDM engine has 10mm plungers according to the code. My spare injection pump (history unknown) has a code that also indicates 10mm plungers.

However, my two pumps have different size tapers on the shaft. My spare requires a different drive sprocket with a larger bore.

I have a photo of a 3.3L 4BC2 pump. Unfortunately the tag is dirty enough that the small row of numbers can't be read.

thanks all for the info!

so are you fellas recommending larger diameter plungers? or stick with the same if replacing? The missus has given permission to 'make it work and work well' so the budget has stretched a little...

This is the first deisel pump I've ever worked on, so be gentle if I'm asking baby questions!

Originally Posted by Dougal

Your engine was export spec? From a truck sold new in Aussie?

My JDM engine has 10mm plungers according to the code. My spare injection pump (history unknown) has a code that also indicates 10mm plungers.

However, my two pumps have different size tapers on the shaft. My spare requires a different drive sprocket with a larger bore.

Sorry I don't know its history.

if you;re going to up it might as well go the bigger ones but get the torque cam that goes with them as well.

Originally Posted by EchiDna

thanks all for the info!

so are you fellas recommending larger diameter plungers? or stick with the same if replacing? The missus has given permission to 'make it work and work well' so the budget has stretched a little...

This is the first deisel pump I've ever worked on, so be gentle if I'm asking baby questions!

Not my recommendation unless you need more fuel than you can get now.

If it goes to a pump shop, tell them that a turbo has been fitted and ask them to calibrate it for a bit more fuel than a stock turbo'ed engine.

More fuel will get the turbo performing better, and increased boost lowers egt. It might produce some black smoke when you floor it, until the boost pressure builds (because you don't have a boost compensator). If the black smoke doesn't clear reasonably quick, you can easily turn the fuel down.

Originally Posted by Bush65

....If it goes to a pump shop, tell them that a turbo has been fitted and ask them to calibrate it for a bit more fuel than a stock turbo'ed engine....

Thanks for the info ... umm but how much is a "bit" - remember, you are talkin to a diesel pump infant here are we talking 1cc/500 strokes? or should this be done in conjunction with a dyno run or similar?

Originally Posted by EchiDna

Thanks for the info ... umm but how much is a "bit" - remember, you are talkin to a diesel pump infant here are we talking 1cc/500 strokes? or should this be done in conjunction with a dyno run or similar?

Does anyone have stock injection volumes?
The US engines should have it listed on their EPA tags. But I haven't seen one yet.