View Single Post
  #9  
Old 11-19-2007, 01:25 AM
Diesel911's Avatar
Diesel911 Diesel911 is offline
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,038
When I did this sort of thing where I worked to remove the exhaust housing bolts work carefully. Squirt with penetrating oil, take a good sturdy flat ended punch and hammer and smack the center of the exhaust housing bolt heads several times followed by heating the housing area with a propane before you attempt to remove them.
When the bolts start moving (I often used a combination wrench the box end on the bolt head and tapped the end off the wrench until the bolt loosened) a little; shoot some more penetrating oil into them and move the bolt back the opposite direction to help the oil feed back into the threads. Continue to go in and out with the bolt trying to advance the bolt out a little more each cycle. Tapping the head of the bolt some more can also help as well as more heat and more penetrating oil. This usually loosened 95% of the bolts with out breaking them off.
It is also a good idea to get the correct bottoming tap and chase the threads in the housing after the bolts are out. When you assemble it is a must to use a high temp ant seizure compound on those bolts. In fact if you had a lot of trouble getting the bolts out and the rebuild kit did not come with them it is best to replace the bolts with new ones of the same grade.
I have not had my Mercedes turbo apart yet so I don’t know if it applies to Mercedes turbos but some Garrett (Air Research) turbochargers have exhaust housing bolts the ends of the bolts actually are exposed to the hot exhaust gases and actually causes the threaded bolt ends to mush over; meaning you need even more care to remove them.

Air leaks on the compressor (pressure intake) side can cause whining noises as can metal to metal contact. (My boss used to get a thin piece of paper about 1 inch wide and 6 inches long and have some one accelerate the engine and run the paper around anyplace possible where there could be a leak; if the paper fluttered that was where the leak was.)
If neither of the 2 is going and it is normal sound??? Try an internet search.
Reply With Quote