FSM thermostat quest??

[Guest ekvh]

In the FSM, my 88 Reatta says at the end of page 6B5 to install the thermostat with pointed end up and towards the radiator, but the diagram on 6B6 shows it the other way around, pellet end up. It is pointed end up isn't it?

[89REATTAJIM]

I believe that there was a post awhile back that one of the FSM's had it wrong. Possibly Padgett??..... Jim

[Guest Bobby Valines]

If you do put it in upside down you will know it your car will overheat in no time. I would think pointed end up.

[Guest ekvh]

I just went and asked for the rubber gasket that fits around the thermostat. I know I read last year and even had pics from people saying how this gasket, like an o-ring with a groove, went around the thermostat and then slid into the housing. Well, I could not get that piece to fit into the housing without tearing it to shreds. Last year I ended up using a bunch of silicon to get it to seat properly. When I asked today, the guy took me in the back and said he had two that showed for the Reatta. The first one he handed me looked too small, the second was the O-ring for the elbow. I almost left when I took the smaller one out and studied it and I think it goes on the top of the thermostat. It then makes a cushion to press the thermostat tightly into position. It has room for the two tabs from the elbow piece. I'll find out tomorrow.

[Guest Drake]

ekvh, you have the right gasket now. A little white grease on the neck o-ring, and you're all set.

[padgett]

Smaller one (not an O-ring) goes into the water neck. O-ring goes into the groove on the outside of the water neck.

I clean all surfaces first. Shiney clean. Pointy end of the thermostat goes up unless you have a "reverse poppet" which you won't. Important thing is that the pellet (brass cylinder about 3/8" in diameter faces the engine but I don't think it will assemble properly otherwise.

With all surfaces clean and liberal use of white grease, the neck should just push in by hand (I sometime push with a big screwdriver centered on the top. Bolt just holds it in place DO NOT use to try to pull neck down. 10-12 lb-ft works for me.

Note: a "wobble" 1/4" extension and a short 10mm 6 point socket make life a lot easier, the manifold flange is in exactly the wrong place for a straight down shot - obviously the engineer who designed it never had to remove one).

I use 180F Stant "SuperStats" p/n 59848 usually in stock at Pep Boyz (plug) & just put one in the White car. My observation is that the SuperStat will hold to about +/- 1 degree of the set point where with a conventional 'stat it is more like 5 degrees, usually on the high side. It matters to me.

O-ring (Fel-Pro 0427 or equivalent) is always changed if the neck comes off (e.g. when flushing the coolant system) and it has been more than a month or two since replaced (Keep several on hand). If the inner rubber seal seems good I generally reuse them since it will not cause an external leak.

BTW there is a TSB on that inner gasket. Seems without it enough coolant could flow past the thermostat to make getting heat a lengthy process. Also 180F thermostat will generate more than enough heat even at 0F (observed) and will warm up to operating temperature just as fast as any other. If there were a 44 mm 170F thermostat available, I'd buy some.

[Guest ekvh]

Padgett: As to the heat being a lengthy process, yesterday it would not get above 150 even with a clamp on the upper hose. It would not keep the TCC engaged. Of course it was pretty cold, today it is -50 with the windchill so I am heading out to see if I can find a carwash I can sneak it in long enough to change it before I head home tomorrow. I doubt it will give enough heat to keep the inside warm. I agree with you on the lower thermostat in the summer, but in the winter where I am, you want a 195 for heat. I agree with your ideas on the 180 thermostat, but was thinking, if you have a 180 thermostat, it is going to open more often and perhaps keep the actual radiator temp warmer and thus defeat your purpose. However, watching the engine temp in hot summer driving, the 3800 engine tends to get a bit warm. I have an aux trans cooler laying around at home. I plann on putting it on soon.

[Guest ekvh]

I just found an empty car wash and the attendant was nice enough to let me in. Fen minutes, no leaks, heated to 195 in no time. I will try to post the part number later for those interested. If your car doesn't have one of these, it takes much longer to go into Loop and for the TCC to be engaged.

[padgett]

Am serious, Bonneville (also "C" 3800) would roast out with 180F thermostat even after sitting out on a 0F night in Indiana. The inner circular rubber gasket does seem to be necessary for quick warmup: PepBoys (Fel-Pro ?) p/n 35126