PeachParts Mercedes-Benz Forum - View Single Post - GreaseCar WVO System

Blevinsax · #14 10-14-2006, 02:12 AM

Okay - I left the 350SD with my mechanic for two days and he checked, checked, and rechecked everything in the GreaseCar system. Everything checks out - no amperage problems, power is good, solenoids are working, but I still have these same two problems:

1. the car stalls after switching to grease from diesel, then restarts fine with a brief priming.

AND

2. after shutting down and leaving the car on grease with the motor off for at least 15 minutes, the car stalls shortly after restarting, then restarts fine with a brief priming.

This tells me that when the grease line is not flowing, it is running back down the line and air is getting into the line. It seems to be up front in the system because it takes longer to reprime the motor if it has been off for a longer period of time, but it reprimes much quicker if it was running very recently. So where is air getting into the line???

Quote:

Originally Posted by WD8CDH

Also using an auxillary lift pump for veggie and the stock lift pump for diesel helps prevent air problems and allows faster switch over and purging too.

I should also mention that I already have the auxiliary pump from GreaseCar - Initially we thought the stock lift pump was not strong enough to pull grease from the trunk, so that was the first thing I did when this problem surfaced, but it did not remedy the problem. It is now one of the primary suspects for the air leak, too.

This system is so close to perfect, but this last little hitch is really annoying. The car runs so great on grease, but I cannot switch on the fly or the motor will die. Ultimately that causes me to run a lot more on diesel than I would like because I have to find a place where I can safely stop so I can restart the motor after it shuts off when I switch to grease. I've already burned through a half tank of diesel in a week - I was hoping a full tank of diesel would last 6-8 weeks like it does on our VW. I know the VW motor is smaller, but so is the VW diesel tank at just 14 gallons compared with the 22 gallon tank on the Benz. A tankful certainly won't last that long at this rate - and that stinks because I have an endless supply of WVO I could be burning if I could get it working properly.

The one thing my mechanic discovered is this:
While driving - when switching from diesel to grease, he let it go just until the motor started to die, then he flipped the grease/diesel switch back and forth several times. When he did this, the car picked up and kept running. Naturally, I'd rather not have to do that every time I change fuels - I'd like to get to the bottom of the problem. After all, this IS a Mercedes!! It's the nicest car I've ever owned!! I shouldn't have to be driving it like some half-ass redneck pick-up truck that only works if you 'whack it' or 'thump it' or otherwise 'jimmy-rig' it! As it is right now, I have to 'whack it' under the passenger dash to make the A/C blower work , but never fear - I've already ordered a new fan blower motor, so I wil have that repaired sometime soon!

Okay - Anyone have any suggestions that might help me figure this one out?

P.S. I posted this same thread over on the GreaseCar forum and got NOT ONE response!!!