Lizard944

Short story made long...I bought an updated water pump for a 1986 n/a, and in anticipation of it arriving, I bought a stock temp 80deg thermostat 944.106.129.05. The pump actually came with a T-stat 83deg 944.106.019.00. All resources say that this T-stat is to be used with the updated pump. The problem is that I did the stove top boiling test and the 80deg was perfect but the 83 opened way late, around 90c before it started opening. Can I use the 80deg with this pump? I see no physical differences other than the 83 came with a thicker rim gasket and some shims, but the 80deg also came with the thicker gasket in the box. I've been burned by this in the past by installing a T-stat that tested out of specs so I don't want to do this again. Also, does the shim(s) go into the pump first before the T-stat? Thanks folks.

austin944

Search yields this:
https://rennlist.com/forums/944-turb...tat-parts.html

Lizard944

Thanks Austin. I did a thousand searches which yielded nothing conclusive. I get nervous when I see part suppliers state, "You MUST use 944.106.019.00 with this pump..." The thread you supplied is probably the closest to an explanation that I've seen. But even here, the responder's answer was a lukewarm, "should be ok if it fits." I'd be more comfortable seeing a 30 page lab analysis on the differences and a statement such as; " The only difference is the temp rating and the supplied shims to correct the grove height...I've used this for a million miles and the chief Porsche design engineer uses this in his car." ..LOL! Anywho, the info I have gathered suggests that there are no differences between the 83 and 80 thermostats other than the supplied hardware that comes with the 83deg to make it fit into the updated water pump, and the temp rating itself. I just wanted to rule out that there was some TSB that I missed stating that the 944 should now run at 83deg. I had an 83deg T-stat in before and it ran a little on the hot side. Thanks again. ---Lizard.

austin944

Well then, how about Clark's Garage:
http://www.clarks-garage.com/shop-manual/cool-07.htm
http://www.clarks-garage.com/shop-manual/cool-08.htm

JBC1

Lizard, I am fighting through this same issue right now. I installed a new Whaler 83 degree C Thermostat from Pelican Parts and I did not test it in hot water on the stove. I should have done so. Yet, I have a laser thermo gun and I know that it is not opening until between 85 and 90 degrees C as that is when the lower radiator hose starts to get hot and water flows through the radiator. Additionally, my fan thermo switch is rated at 92 -102 degrees c. So, the fan comes on a slightly over the middle mark. So, my temperature gauge runs about 1/4 too high. I have ordered a 71 degree C thermostat and a new fan thermo switch rated at 75 degrees C. This should keep the car running at the middle mark. I read a post from another 1983 944 owner and he did the same thing and his car runs perfect now.

Do you have a Whaler thermostat?

Regards,
JBC

FIA-F1

Not to way over simplify this thread but I had ongoing overheating problems with my '91 S2 and read the forum discussions like this to research thermostat temps, etc. in the end, I went with stock, OEM spec for the thermostat and water pump from the dealer for my '91 and it has been perfect. Temp guage runs consistently just under the half way mark. It may not have been the cheapest path but it was the right one for me.

MAGK944

dont forget the fan switch is matched to your coolant thermostat. A 71 thermo matches a 75 switch and a 80 thermo matches an 85 switch, there is also an 87 thermo. 80 or 83 is the same apart from attaching parts that are included, as you figured out. Some people fit higher or lower thermos and switch to accommodate their climate, just check you have the right 85 switch to match your 80/83 thermo in case the PO fitted the wrong one. Good luck!