Carbon Build- Up in Intake
 

Hi Diesel Guys - I have sort of a problem with my 87 300 Turbo D- 124 running a Frybrid Veggie system. She runs great on veggie once warmed up, however very shakey and rough on diesel until warmed up.

Also I now have a bad oil leak and I am still trying to find out where. I ordered a new valve cover gasket but I think it may be leaking around the turbo or the oil line to the turbo - not sure yet.

I removed the intake plenumn and saw lots of greasy carbon inside the tube but it looked real clean looking down into the turbo. See pix. Thanks for any help in advance.

Sorry - trying to uplaod pix but the forum limit is only 65kb and my pix are 149kb- how can I resize them to fit or is there another way. I have no problem on other forums uploading pix.

pix?

typical EGR clogging?

upload to another location and then link to them here.

http://i127.photobucket.com/albums/p...atchero052.jpg
http://i127.photobucket.com/albums/p...atchero050.jpg
http://i127.photobucket.com/albums/p...atchero049.jpg
http://i127.photobucket.com/albums/p...atchero047.jpg
Lets see if these pix come up.

Very typical and very difficult to clean. Cleaning doesn't lead to a worthwhile improvement in performance or mpg, most say.

Sixto
93 300SD 3.0

OK, this dirty oily build up (which is soft and not too hard yet) is probably not the cause of my start up shake/knock? I'll change out the EGR valve, valve cover gasket and clean the plenumn and see if there is any improvement.

The oil leak can be very frustrating to track down.

Don't change the EGR valve, just plug it's vacuum line.

Do you mean, just leave it in there disconnected after the vacuum line is plugged?

Will the valve then be Open or Closed?

This could be the cause of the oil being forced out of the engine. A clogged EGR?

Buy some vacuum line and cut a small piece, plug it with a screw or something and slip that short blocked line onto the EGR. Also plug the end that you've now left disconnected.

A badly blocked EGR could cause performance problems and oil spewage. Happened to me on my TDI.

1: Yes. Plug the vacuum line with a BB or other object that will seal the hole and leave the EGR in place.

2: The EGR will stay closed all the time.

3: EGR has no effect on the oil leak but it will stop the build-up in the intake.

The leak will probably be one of the oil feed or return gaskets for the turbo.

For the rough running, do a search here for "Diesel Purge". It's the cheapest first step.

I see what your saying now. Cap off the vacuum line and the EGR, but hopefully the EGR is in the open position to vent gas pressure out of the vavle cover.

The EGR has nothing to do with valve cover gasses. The carbon build-up is caused by oily crankcase gasses (from the valve cover) passing through the intake and combining with soot from the exhaust introduced into the intake through the EGR valve.

When the EGR is disabled by plugging the vacuum line, the exhaust soot will not be able to enter the intake to create the build-up.

Definately typical oil/grunge build up from EGR. Mine looked just like that when I took it apart in October. PITA to clean it out.

Don't forget to pull out your over boost sensor and clean the tip of it out. It is attaced to the intake manifold.

-Jim

Unless the EGR is so choked up that it's stuck open.