1984 300sd California(i know CARB requires different equipment on Cali cars).


I am recently having a problem with turbo/engine. As it spools up the turbo cuts out and makes a hissing/scratching(kinda like when your brakes are bad and sqeek and drag) noise, I dont think its the turbo bearings, or i would hear it as it spools up. It only happens around I believe 20mph or around 2000rpms I Can't get up to 50mph. Turbo sounds ok and whines like normal and then at around 2000rpms it looses power and makes that noise i mentioned. I think its a wastegate issue or EGR. Anyone have a turbo issue of loosing boost?

New fuel filter, no fuel leaks(lines, injectors, pump), banjo bolt line going to ALDA cleaned.

 

Thanks will look at turbo shaft play tomorrow. New to turbos and diesels.

Do you happen to know what turbo brand I have? I haven't seen a turbo like mine yet in the 300sd engine pics on the net or anywhere online. Is that the wastegate on the side of it? If it is the wastegate it looks like its hooked up to the vacuum line system. Thanks.

 

THANKS A BUNCH, its been frustrating me trying to find out that part on the turbo assy(Air Recirculation Valve) and the turbo itself.

My understanding of the Air Recirculation Valve and EGR that you mentioned is that if they were INOP and stuck in a closed position(acting as if they were not even installed) would give me a more smoother/stronger boost, reclaim some acceleration and Hp's?

If the Vacuum line was removed from the Air Recirculation Valve how would that effect the EGR and car in general?

Im also assuming the Air Recirculation Valve is a California requirement do to CARB?

 

No turbo play in any direction. I tested the EGR and ARV by disconnecting them and plugging them up. Problem seems to have gone away, leaning toward one of these dumping boost somehow.

 

Either you have some problem with the Tubo or your method of checking the Play (clearances) leaves much to be desired. When the Turo brand new there is paly between the Bearing and the Turbo Shaft and again play between the Bearing OD and the Turbo Beaing Housing ID.
The above is side play.

On a new Turbo there is also a tiny bit of in and out play but with Oil on the Bearings you might not feel that. It would show up with a Dial Indicator set-up.

From you description of the sound the Turbo My best guess is that your Compressor Wheel is making contact with the Compressor Housing.

If you remove the Air Inlet and get a Strong Light and a small Mirror you may be able the rubbed area on the Compressor Wheel. The Metal will be mushed to one side on the side of the Fins.

Better ways. Remove the Compressor Housing and take a look. Remove the what it takes to get at the Exhasut/Turbine end of the Turbo Charger and stick Your hands in and push the Turbine Wheel towards the Compressor Housing and at the Same time Turn it and listen to see if it scrapes on anything.
Do the same as the above but reach into the Compressor Housing and put a finger on the Shaft Nut and try to apply some side thrust as you slowly turn the and push the Turbine Wheel towards the compressor Housing; again listening or trying to feel any scraping.