Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

Radiator Cap Pressure Too High?


maitai11's Avatar
Member

Join Date: Jun 2000
Posts: 91

09-08-04, 12:01 PM   #1  
Radiator Cap Pressure Too High?

Just trying to figure out whats going on with my 1988 Camaro, 305 Vin E, Throttle Body Injection...

I've replaced:
The radiator
Hoses
Cap
Thermostat

But my radiator cap is set at 16 psi...is this too high? Should I go 15 psi instead?

Am missing, and will replace my air dam below

The car runs very hot...not losing coolant internally as far as I know...There are times when I have to run the heat (In Hawaii!!) to make it to my destination. If AC is maxed, it (the temp) spikes pretty quick (new compressor and accumulator)

Guess I'm gonna replace the water pump tomorrow...i believe it's the original (with 136k)...I'm hoping that the impellars are degraded and that its the source of the problem...car just started overheating about 6 mo ago.

Btw, I did flush the system

Thanks!

Maitai

 
Sponsored Links
easywind's Avatar
Member

Join Date: May 2001
Posts: 516

09-08-04, 12:17 PM   #2  
As I remember these Camaro's had very marginal cooling systems to begin with. If your air dam is missing I would wait before replacing the water pump as the air coming in to the engine compartment is not getting to where it should be. Get the air dam on first, see what happens and go from there.

 
carguyinva's Avatar
Member

Join Date: Nov 2003
Posts: 1,147
VA

09-08-04, 12:58 PM   #3  
F bodies...

...are bottom breathers (camaro and firebird) and get their air for cooling from the road surface. a missing air dam will cause overheating at cruise speeds for sure. install a new one before anymore repairs are attempted

 
car nut's Avatar
Member

Join Date: Aug 2003
Posts: 478

09-08-04, 04:57 PM   #4  
Impellers can go bad but this is rare. A water pump is the last thing I would try. If this has a clutch fan the clutch may be bad. When the engine gets hot the fan should lock up and be pretty noisy, and sound like an airplane. Shut the engine off when it is hot and if the fan turns easily by hand the clutch is bad.

The air dam will have minimal effect if you are over heating at slow speeds.

If you have electric fan(s) are they coming on when it gets hot? If not you need to see why.

Are the AC condensor and radiator fins plugged with bugs, leaves, etc? If so hose them out & gently clean them. How does the inside of the radiator look? It may need to be flow tested and cleaned or replaced if necessary.

The efficency of the radiator deteriorates over time and old radiators get to the point where they wont cool adequatley.

When it gets hot let it run and spray the radiator with a good hose stream. If the temp comes down either the fan is not doing its job or the radiator is plugged or both. If the temp will not come down you have other problems such as a bad thermostat (new ones can be bad) head gasket etc. If the problem is when you are at speed the bottom radiator hose can collapse and block coolant flow if it is soft or if there is no spring inside.

Also if the fan shroud is missing or broken the fan will be less efficent. If you are with in 1 lb. of the factory pressure on the cap it should not be a problem. Higher pressure just raises the boiling point.

Good luck and let us know what you find.

 
maitai11's Avatar
Member

Join Date: Jun 2000
Posts: 91

09-28-04, 09:02 PM   #5  
Air Dam Magic

Gentlemen;

I replaced the Air Dam. I was astonished (but not surprised) to learn that my cruising temp was now 50 degrees cooler...My car doesn't even reach 220 deg operating temp any more. The AC works like a charm now too. Thanks for all the input and suggestions. BTW, just because, I replaced the water pump. I put in a new delco and opened the old one up to inspect. Pretty bad corrosion, but the impellar still moved freely...who knows - I believe the pump was original w/137k miles on it. It's done now though

Now, I'm just getting a little hesitation/stumbling on acceleration...maybe time for tune up. I think I'll start there

Maitai

 
carguyinva's Avatar
Member

Join Date: Nov 2003
Posts: 1,147
VA

09-29-04, 03:56 AM   #6  
be sure to clean the throttle body...

...with your tune up...

 
maitai11's Avatar
Member

Join Date: Jun 2000
Posts: 91

09-29-04, 10:29 AM   #7  
Thanks again

 
Search this Thread