New style primer pump...does it work for anyone else?
 

I just switched my manual primer pump from the old unscrew-pull-push type to the new push-push kind. It was a PITA because of a bunch of VO related hosing/valves, etc in the area of the pump (although I'm not looking for any sympathy here :D) which was the reason to change it in the first place...the old was was really difficult to operate.

Anyway, after getting it swapped out and reconnecting everything, I pumped and pumped and pumped and the clear filter never filled with diesel. I though I had the hoses connected wrong. I followed everything and it seemed right. Pumped some more, still nothing. I said "screw it" (pg-rated version) and I cranked the engine. It fired right up, I kept it just above idle, waiting for the stumble from any air, a little stumble came and went in the idle and it was all good. Shut off the engine, went back to the pump...pumped, pumped, didn't really feel like it was moving anything.

I thought I remembered using the old style pump and it would move diesel through pretty well. Do I need to remove the IP inlet or an injector line to let the diesel flow? Anyone have experience with the new kind of primer? I was so happy when I finally got around to doing this...AND using my new crow's foot set...talk about a let down after I was done.

The primary filter won't fill with fuel, it will always have a large bubble. Just keep pumping until you hear the pressure relief valve on the side of the injection pump opening when you pump.

i had similar experience. new style pump seems like it requires 5x as many pumps as the old style did. I seen some folks say they use their mity vac to pull fuel up from the tank.

I haven't had this experience at all, the new style works great for me, and 30-50 strokes is a matter of 20 seconds.

I've had 3 or 4 cars with them and they work great! I did have one I had to replace once, but that is because it leaked when you pumped it.

I had my old one fail and start leaking all over my garage floor and motor. I installed the new one and a few pumps and I was good to go. Hasn't leaked since.

Same here. But I have read about complications when alternate fuels are involved.

Mine that I replaced on my 240D worked great on vo. Much nicer than unscrew pump push hold screw. Its only a primer pump if after pumping you went and started your engine and it ran, then it did its job.

I've never had a problem with mine, in fact, I even have a few pictures from when installing it: http://www.peachparts.com/Wikka/PrimerPump

When I bought the car the new style pump was already there; but I have on the job experience with the older style ones. I like the new style Primer Pump better.
If you are using VO it may be that the VO is thicker and harder for the new stye Primer Pump to move and as the other member said the new style Primer Pump may move smaller amounts of fuel when you pump.
Also last year there was a member who got a new, new style Primer Pump and it was no good. He went back and got another and that one was also no good. He took it back and got his money back and went to another parts supplier and bought another one that turned out to be a good one.
He figured with 2 bad pumps fromt he same place there must have been a defective "Lot" of pumps. Going to another seller reduced the chance of getting another from that defective Lot.

I have the new style pump on my '78 300D.
I ran it out of fuel a few weeks ago and thought oh great, here we go...
It only took about 15-20 pumps to pull fuel from the tank and it fired off without a problem.

The primer will never pump VO...I'll always be in diesel mode when the engine is not running and I'm pumping fuel. VO gets switched once the engine is hot.

hmmm....

But I didn't get ANY fuel entering the primary filter...I don't remember hearing the pressure relief valve opening, but I wasn't listening for it...I'll try that.

I wonder if I got a bad pump...I bought it months ago, don't remember where, maybe fastlane. But if so many other people have had success with it, I'll keep playing with it. For now all is good...I just don't want to need it just yet :eek:

Thanks for the comments.