Former VWDieselParts.com Forum

750 miles since Complete bottom end rebuild with new head and rebuilt injection pump. Lack of power. Louder and shakier then I remember. Lots of black smoke on steeper hill climbs. Just took the new injectors out to find a butt load of carbon build up in cylinders 2 and 3. Doing a liquid molly fuel pudge tomorrow morning hoping to clear up the carbon build up. Any ideas what could be wrong? Clear line to IP with no air. And everything else appears correct. Maybe my pump timing is off. Maybe I didn’t break the rings in properly

How did you time it?

Shop did dynamic timing. I have since used a dial indicator and found my timing was way far advanced. Turned it back down to .89 or so and everything evened out. No more carbon. No more black smoke. Power increased but still isn’t great... I don’t expect much from 50something horse power but you always wish it would do better up the hills

Thanks for the update.

With my pump at .89 still no smoke and otherwise power seems fine but this damn thing is way too shaky!!! Was never like this before the rebuild. I’ve checked and re tourqed all the mounts. still no air in the feed line but does appear to be some very small bubbles in the return line. Getting fuel to all injectors and they were all pop tested and passed.

Do you have clear lines between the injectors?
Even a little air coming from the pump is a bad sign,.. I mean if you've just opened it up it'll take some time to clear the small air bubbles from the system.
Sometimes it is coming from an injector, into that output banjo.

Have you watched the lines before and during a startup to see if there is more air?

Runs/sounds the same even after warmup?