FityOne

Does the oil circulation system on the 951 have a thermostat or switch that controls circulation to the oil cooler. I have a feeling that my high temperatures is a result of improper oil cooling.
Anyone know where this is located ?

Thanks

GrantG

I'm pretty sure there is no thermostat - open all the time. However, if I'm wrong, I'd love to know where it is too...

Steve Lavigne

There is an oil cooler thermostat. If you look to the right of the oil filter, there is large internal hex cap/bolt and it either sits under there is is a part of that bolt. Unfortunately, my knowledge of it pretty much ends there.

WillyC4S

Steve is correct on the oil thermostat location. It takes a large 17mm hex driver/allen wrench to remove this bolt. It's an all aluminum bolt. The same hex driver/allen wrench to remove the transmission fill & drain plugs is used to loosen this bolt.

I've taken off my oil filter housing, but I didn't remove the oil thermostat yet. I tried yesterday, but it is definitely on there very very tight!

I don't know if there are any seals or such to replace once you separate everything. There isn't too much written up on this. There's more info on the oil pressure relief valve than the oil thermostat.

Hope that helps.

*****

Bri Bro

I also tried to remove this bolt and couldn't get it to break loose. I decided I didn't want to break something trying to get a look at a part that was working correctly.

GrantG

Are they known to fail? My car gets very hot at the track. I'm curious to know if this could be the reason, but i don't want to damage it either by removing it...

FityOne

Well, I have done almost everything to my cooling system and the heat buildup over time still occurs. A 944 mechanic friend of mine thought that this might be the culprit based on the symptoms. This was the same guy that checked the car out when I bought it, he is pretty good at solving problems. He said that the thermostat over time tends to get a little crudded up and hence sticks preventing full circulation to the cooler, hence resulting in a slow but steady heat buildup until your fans keeps cycling on and off at moderate speeds. This is the explaination I understood, but I could have interpretted it differently. Anyway, most oil coolers have a thermostat so that when cold, the oil does not circulate and hence is allowed to heat up to about 160-180F after which it is maintained at that temp by allowing circulation to the oil cooler. Anyone know where to get a new one ?

David Floyd

Here is what lies under the cap. Thermostat is stamped 105 C



I am replacing the stock oil cooler with a 25 row Mocal and also a Mocal inline thermostat, now should I just leave the stock thermostat out and run just the Mocal ?

WillyC4S

David,

Cool pictures! I haven't gotten mine open yet, even with a 17mm long allen wrench. I'm thinking of leaving it alone for now. It's always reachable next to the oil filter anyways, not like it's hidden underneath the heat shields ...

A couple of questions:

1) Were there any other components other than the items in the picture? Were there any seals of any kind inside? How about a large aluminum washer around the cap, mine looks like it has the washer (as least from the outside inspection).

2) Where the components very dirty or had sludge on the surfaces? I'm assuming that the pictures represent post-cleaned samples of your oil thermostat?

Thanks,

*****

David Floyd

*****,

Yes there is a washer around the cap, other than that what you see is what you get, no seals or o-rings ect.

The parts are wiped off but there was no sludge or build up of any kind, the engine has 114k miles

RAD951

Hey David,
how much are those mocal oil coolers?? I hear they sell a complete kit for the 944 turbo. Or is it cheaper to just buy the core and retrofit it in using your own hoses?

David Floyd

Rad951,

<a href="http://www.batinc.net" target="_blank">www.batinc.net</a>
25row 7x12" Mocal $181.50
22mm x 12an adapters 2x $17.50
inline Thermostat (optional) $94.50

Then buy -12 stainless hoses and -12 an fittings

I am deleting the stock cooler and hoses and may leave out the stock thermostst.

Trying to mount in front of the radiator, have not come up with a mount I am satisfied with yet.
A cooler with deminsions of about 4x20" would be a better fit.I think Danno has mentioned a RX7 stock cooler deminsions work well.

Loki

Does anyone use an aftermarket temp gauge? I began to wonder about the reliability of the stock gauge because the gauge and the cooling fans(on/off) never seemed to correlate. I also noticed that I get two different readings when the car is running and when it is shut off(key in on position, gauges active). No matter how hot it reads while running, when I turn the engine off(key in on position) I get a much lower temp. BTW I just replaced my thermostat a couple of months ago when I was doing oil-cooler seals. Anyone ever have there oil thermostat fail?

Chris '86 951 now 48k

WillyC4S

David,

Thanks for the info. I'm not taking mine apart, so I'll just have to live with your pics.

*****

David Floyd

I am installing a Autometer oil temp gauge for my new engine, drilled and tapped the large banjo bolt on left side of oilpan (turbo oil drain)