ZR-1 Net Registry Forums - View Single Post

WVZR-1 · 10-20-2013

It would be very wise if "all" owners actually checked that fitting when doing maintenance or if you don't remember ever checking, do it! The early production fitting was used in most GM's of the time and the material actually swelled and became fatigued. It wasn't uncommon to have these fail on any GM that used them.

I don't know how you would remove the threaded aspect of the nipple in the ZR-1 short of removing the t-stat housing and doing it on the bench. I've never needed to so.

Jerry of course has them but if you were in dire need it should be "on the shelf" at most GM dealers, ACD jobbers and most auto parts stores. The service part is certainly the more desired product!

If you can't get a 1 1/16 (27mm) end wrench on it you need to be concerned. The OE is only similar to Cliff's image but Cliff's is what the later "service part" would appear as.

10-20-2013	#3
WVZR-1 Join Date: Oct 2004 Posts: 1,884	Re: thermostat housing nipple broke It would be very wise if "all" owners actually checked that fitting when doing maintenance or if you don't remember ever checking, do it! The early production fitting was used in most GM's of the time and the material actually swelled and became fatigued. It wasn't uncommon to have these fail on any GM that used them. I don't know how you would remove the threaded aspect of the nipple in the ZR-1 short of removing the t-stat housing and doing it on the bench. I've never needed to so. Jerry of course has them but if you were in dire need it should be "on the shelf" at most GM dealers, ACD jobbers and most auto parts stores. The service part is certainly the more desired product! If you can't get a 1 1/16 (27mm) end wrench on it you need to be concerned. The OE is only similar to Cliff's image but Cliff's is what the later "service part" would appear as. Last edited by WVZR-1; 10-20-2013 at 07:10 PM.