617. wobbly motor - PeachParts Mercedes-Benz Forum

davidp · #1 03-17-2013, 06:25 PM

Used veg.oil for a year.now my engine has the shakes. Adjusted rack damper no difference. Has the veggie oil killed my injector pump? What needs to be replaced.changed fuel delivery pump.what next?

GregMN · #2 03-17-2013, 06:36 PM

Water in your fuel with damage the injection pump.

Injecting cold (below 160 degrees F) VO will damage the cylinder by most likely impacting the rings into the pistons with a build up of carbon.

With no information about your system on the car and how you process your fuel, all I can respond with is generalizations.

Volker · #3 03-17-2013, 06:41 PM

They always kind of shake, don't they?

I remember on a 300 TD it was shaking only a little but the car shaked like crazy... new motor mounts and the car became nice and smooth (relatively) but looking at the engine, it was bouncing around all over the place!

fender_bender · #4 03-17-2013, 07:54 PM

Motor mounts was my first thought.

davidp · #5 03-17-2013, 08:20 PM

Yes cold injection, my veg oil was filter to 10 microns and mixed with diesel. And at different percentages .I tried a different injector pump but could never get timing right as it was a 602 pump. So it didn't shake .I don't think its damage engine wise. I think its pump damage!

sleepstar · #6 03-17-2013, 08:44 PM

maybe because of the VO you've got some leaks in the rubber fuel lines. one of the motor mounts is placed directly below the lift pump where theres lots of hoses above. maybe you had a leak down on there and the motor mount is now shot.

Diesel911 · #7 03-17-2013, 08:47 PM

If you have the Stock Nozzles the tiny Passages could be plugged with Carbon.

Item 12 shows the tiny passages drilled in the Hole of the Injector Pintel.

Even on Diesel Fuel if you don't do regular Injector Purges the can get blocked with Carbon; at least all of the ones I pulled from My Car were blocked Solidly.

barry12345 · #8 03-18-2013, 01:15 AM

Your injection pump does not have all the elements contributing properly so there will be vibration or rough running issues. Your retarding the inecction pump to partially eliminate the severe number one cylinder knocking does not solve the issue. It just masks it somewhat.

You really should examine how to do the milli volt method of checking and adjusting the number one element that is so far off. Or grab a used injection pump from a pick and pull yard. Getting two threads going that perhaps involve the same issues adds complications.

davidp · #9 03-18-2013, 07:37 AM

where is this millivolt information?

GregMN · #10 03-18-2013, 08:25 AM

Do a compression test before you spend any money on parts or spend too much time messing around with settings on things that don't usually change much in a single year's time.

Simpler=Better · #11 03-18-2013, 09:17 AM

2x:
Your motor mounts are probably shot from old age (they just plain wear out)

Adjust your valves, do a compression test.

If the compression is good, then get your injectors cleaned/ balanced/ possibly new nozzles.

After that I'd check the rack damper and timing

barry12345 · #12 03-18-2013, 04:44 PM

Archives at the top is where there is a lot posted on the milli volt method. Plus thouands of other things. By retarding your timing to get rid or lessen the number one cylinder knock you should also have lost a little power. Primary timing by the milli volt method is a thread worth reading in the archives. If nothing else one can get some insite from others experiences with it.