Help! I noticed a coolant leak from the top side of the timing cover just below the a/c compressor. So before I took it apart, I went and got a cover just in case it was bad from Autozone. It is Dorman part number 635-507 listed for 3.1L. Well once I got the whole thing apaprt, my OE cover was no good (Pitted) but the bad thing was the Dorman part number was slightly different and didnt match the OE one. Some of the bolt holes did not line up, so we went back to Ausotzone and the other 3 they had there were the same way. UGH! So Ive filled in the pitts on the OE unit for now with epoxy, but Id really prefer not to use it because it may happen again. Any Ideas? Or has anyone else run into this issue, of the people at the parts counter have no clue....
Any help is appreciated....

 

What bolt holes didn't line up?

All 660s share the same timing cover bolt pattern, minor differences being that some (RWD) have a bypass hole below the left side water pump coolant passage, and different bolt sizes between different years, but the pattern matches.

Posting some pictures may help discover what may be going on.

 

Maybe the new one is an 82-86 cover?

 

The listing Autozone has is for a 2.8 or 3.1 Liter, it obviously isnt correct. The water pump gasket from Felpro would even match the pattern on the front of the cover. According to the Dorman sit, it fits 82-86 2.8L GM Performance block. Ive emailed thier tech department to see what the story is. If you google that Dorman number, all the descriptions of people who sell it state it fits a 3.1, but it clearly does not. Just trying to see if anyone else experienced this problem and/or prevent someone else from going through the hassle..

The OE Cover was pitted in the coolant bypass holes into the water pump cavity, what is everyone using for coolant? Prestone (Green) or Dex-cool (Orange)

thanks

 

If it fits an 82-86 it won't fit an 87+. IIRC early engines also use a clockwise-rotating water pump which is probably why the water pump gasket doesn't fit either. There are 87+ covers on ebay and also you could grab one off an 87+ S10 2.8 too.