Club 80-90 Forums

Hi! I'm (trying to) rebuilding a Pierburg 2e3 (with the 13mm accelerator pump diaphragm) and to my help I'm following the excellent video series by James Akers. Everything was going smoothly up until the step when I would measure the fuel injection volume. Its really hit or miss weather the jet will squirt a proper amount or not. I've tried to blow "wd40" and then air through the jet and the holes that leads up to it from the fuel bay. Most times the injector jet is just dripping out the fuel or squirts some amount but thats nothing compared to the "jet" that comes back to the fuel bay from the diaphragm housing, please see image.

Could I've missed some basic step? Misplaced some part?
Could a mismatching o-ring/seal lead to this kind of problems?
How much fuel should be in the bay when testing?

The filter on the injector jet is clean as well.

Thankful for any suggestions!

T3 '83 1.9L DG - Camper

There must have been something stuck in the jet, after some additional cleaning I get sort of consistent squirting each pump. 
I still can't seem to get more than 5ml per 5 pumps, instead of the suggested 6.75ml. I've tried adjusting the screw and also slight bending of the arm to eliminate any gap. Does this angle look right?

Hello! The screw on the cam in the latest picture is over to the right which means the accelerator pump is already engaged with a pre-load. Have you tried it the other side to get more per squirt? 

jamesakers wrote: ↑12 May 2021, 13:12 Hello! The screw on the cam in the latest picture is over to the right which means the accelerator pump is already engaged with a pre-load. Have you tried it the other side to get more per squirt? 

Hi! Yes I have. I started the calibration with adjusting the screw on the cam all the way to the "left" and bent the arm to remove the gap without any notable differens in volume. The picture was taken after an hour or so of testing.   I've also verified the orientation of the diaphragm. Could there somehow be too much space between the end of the arm and the little ball at the top of the diaphragm?

Should the ”ball” at the top-back of the jet be movable?

I don't know specifically on that but a ball bearing is quite often used as a plug in a drillway which is what that looks like to me - you can see the pressing around it where it is held in.

Oldiebut goodie wrote: ↑13 May 2021, 11:46 I don't know specifically on that but a ball bearing is quite often used as a plug in a drillway which is what that looks like to me - you can see the pressing around it where it is held in.

Ah then it's a good thing that it doesn't move, thanks!

I'll try to get hold of some straw small enough to fit inside the injectors exit hole and see if something is stuck inside blocking the fuel in to some degree.

Blast it through with some carb cleaner or wd40 with the straw. 

Stesaw wrote: ↑13 May 2021, 14:16 Blast it through with some carb cleaner or wd40 with the straw. 

Thank you, I'll try!

Does anyone have an image of the inner workings of such injector? In the bottom part there is some movable object which is spring loaded, I guess that is to dampering the fuel flow and if the spring is to stiff it would restrict the flow too much?

From what I recall there should be a rubber seal around the injector along with the filter on the bottom.

Just to follow up on this: I did get it to work a little bit better, but I think that either the pump arm is too bent or the jet is still not in perfect condition. I've connected the carb to the engine and is seems to work better than before the rebuild, but I notice some hesitation when accelerating - making me think that the pump volume is still on the lower side. I'll be having an eye open for a new pump arm and a new injector jet, but it won't be my focus as of now.