67 GS 400 is running way hot

**Shakadula** · 08-31-2010, 07:55 AM

Temp is around 210 degrees and goes up to 250 at a stop light. The thermostat is a 190. I think I need to go back to a 180. The car used to run at 200-205 but my gauge might be a little off.

New hoses and running the heat isn't helping.

Thoughts on checking the guage and the thermostat? 50/50 coolent and water

**Bob** · 08-31-2010, 08:44 AM

If it was good and happened suddenly, the thermostat would be a good bet!

**Shakadula** · 08-31-2010, 09:40 AM

I replaced my timing cover gasket and replaced the thermostat at the same time. Don't know why I got the 190.

Thanks.

**henryj11** · 08-31-2010, 03:20 PM

If you have a clutch fan it could be bad. Run it till it gets hot and watch the fan while somebody shuts it off. If it keeps spinning a bit after you shut it off, the clutch os bad. It will slip and not turn fast enough when the engine is running. if that's the problem, replace it with a thermostatic clutch not a viscous clutch as the thermostatic works better. As for the thermostat, once you hit 190 it should be open and flowing. The different temps are just a way to select operating temp. You really shouldnt need the 190 in it though. That was usually used on a smog motor as they run them hotter to burn all the fuel. Put in a 180 and leave the rad cap off while it warms up to make sure it is opening. Hope I helped you a little.

**BigRivy** · 08-31-2010, 09:50 PM

The 190 opening temp of the thermostat will not cause the overheating problem you describe. One that does not open properly might. There is absolutely no problems that should arise from running a 190 degree thermostat. You have other heating problems.

**Shakadula** · 09-07-2010, 09:23 AM

It was the thermo and a bit of a kink in the top hose when it got hot. Fixed and I'm a bit under 210 degrees.

Now for a new problem. I'm never going to get this car on the road at this rate!

Since 2001, I have had 2 rear main seals put in this car. The first one the engine was pulled and the second time in 2008, they did it with the engine in the car. I suppose they dropped the drive shaft and raised the motor because after having it back for 2 weeks, the ubolts shook the rearend diff so bad it killed the rear end. Just my opinion. Anyway, my question is why do I need to replace the rear seals so often. Is my crank bent? Both times they used rope seals. I think I am going to go to the rubber seals next time.

The first shop that pulled the motor were really good and told me they thought my crank might be bent. I don't know how they can tell without pulling the crank out. The second shop was just a bunch of jerks. Put a new carb on for me and now I can't use my Star Wars Air Cleaner. And they said they were car guys.

Thoughts on the crank?

**BigRivy** · 09-07-2010, 03:25 PM

Seal surface may be worn but I seriously doubt the crank is bent if this is a running driving car. Other problems would make themselves known real fast. The main problem that I see is that the rope seals that are sold today in gasket sets are not the same as the ones from when the cars new. This nylon crap they are selling today just doesn't work worth a damn. Try the neoprene replacement. You should be able to replace this without pulling the engine.

**Bob** · 09-07-2010, 05:30 PM

If the sealing surface is damaged, it must be cleaned up, especially if you are going to move away from the rope. I think I would go back to a 180 thermostat too. The 195 is more for newer emissions engines.

**Shakadula** · 09-07-2010, 05:33 PM

Thanks. That's what I thought. How about pulling the motor as opposed to raising it a bit in the car!

**Schurkey** · 10-23-2010, 08:43 AM

Originally Posted by Shakadula

It was the thermo and a bit of a kink in the top hose when it got hot. Fixed and I'm a bit under 210 degrees.

No, you didn't fix it. 210 is still too hot for cruise and idle.

210 isn't hot enough to damage the engine, but at cruise and idle you should be very close to the thermostat rating. Work the engine harder, and the temp might climb a bit.

Originally Posted by Shakadula

[RIGHT]How about pulling the motor as opposed to raising it a bit in the car!

I think it's less work--and better procedure--to PULL THE ENGINE instead of dicking around with the engine in the chassis.

Just because it "can" be done with the engine jacked-up in the frame does not mean it SHOULD be done with the engine in the frame.

Takes about the same amount of time either way; and with the engine out, you can flip it over on an engine stand and work comfortably instead of half-assing the job by working on your back like a prostitute; or overhead on a lift.