1969 Camaro Over Heating issue

[Leon in Mn.]

Do you have the correct fan spacer?  The fan should not be too far into the fan shroud.  It should only be in slightly as to pull air out.  In too far just causes fluctuations in air flow.  You did say that you found the fan touching the back of the radiator?  Just throwing thoughts out there..........also 190 is not too hot.  Many engines with electric cooling fans, (I know yours is not),  did not kick their electric fans on until around 230 degrees Farrah Faucett. 

[camaroman1969]

There is about a inch between back of radiator, and front of fan.  New clutch fan just put in.  We did not use a "spacer.  Nothing came in box when new one arrived.  ?

[camaroman1969]

"IN" is the hose at bottom of radiator, and "OUT" would be hose at the top of radiator.

[bcmiller]

My 468 runs at 200 to 205 on a hot day. And that's not overheating.

If you are not pushing coolant out, I wouldn't worry about it.

[camaroman1969]

This is to JKZ27......Heat indicator was the stock temp gauge.  Went all the way into the "RED Zone"  We are really stumped here on this heat issue.  We don't want to throw good money at this problem, and still have the same issue.  I read that article about "timing and Vacuum"......a lot of good advice here...may try some of those ideas.  Thank you to everyone who chimed in on this issue.   If you have some solid info, please post it.  I need to get my 69 Camaro up and running again.   Don

[camaroman1969]

bcmiller.....My Camaro ran good last season...mid-way in the gauge.  Car ran good.  Now when it approaches the 3/4 point into the gauge, car goes crazy.  Won't idle right, shifts hard, etc.  This block is really touchy.  Major headache.......

[68Zproject]

You might have an air pocket too in your system.  Leave the cap off for a while and let it run until the thermostat opens and you get radiator flow.  Keep the revs up for a while and notice the flow and see if there are bubbles or there's a spot where it doesn't flow for a bit and then starts again.  Might be air getting displaced if that happens and the coolant level will go down.  If so keep doing that until you are sure all the air is gone and top off.

[bcmiller]

You might have an air pocket too in your system.  Leave the cap off for a while and let it run until the thermostat opens and you get radiator flow.  Keep the revs up for a while and notice the flow and see if there are bubbles or there's a spot where it doesn't flow for a bit and then starts again.  Might be air getting displaced if that happens and the coolant level will go down.  If so keep doing that until you are sure all the air is gone and top off.

Good idea! Zero cost to do this, and it may fix the problem.

[bcmiller]

There is about a inch between back of radiator, and front of fan.  New clutch fan just put in.  We did not use a "spacer.  Nothing came in box when new one arrived.  ?

Sounds too close.

Are you running a shroud?  How about some pics?

[Vince]

I'm just throwing this out there as it happened to me.  My car started running hotter than its regular norm and started dying at a stop and being really hard to restart.  It usually didn't restart until it sat and cooled down awhile.  It turned out that the heat riser valve in the passenger side exhaust manifold had frozen shut. 

[68Zproject]

There is about a inch between back of radiator, and front of fan.  New clutch fan just put in.  We did not use a "spacer.  Nothing came in box when new one arrived.  ?

Sounds too close.

Are you running a shroud?  How about some pics?

My stock set up with a shroud has about 5 inches from fan to radiator and the fan sits half in and half out of the shroud. As bc said, pictures would help.

[ban617]

What is the temp of the new thermostat that was replaced ? What compression is the engine & what size is it ? Could it be the sending unit for the factory gauge , I had one bad once & thought it was overheating but it was just the sending unit ... it doesn't have a serpentine system on it does it ?

[camaroman1969]

Hi!  Thanks for your time on commenting on my issue.  We replaced thermostat with a 180 F one.  It's a "high flow one".  I have a 1969 Camaro SS/RS 397/375
car.  Comp. ratio is 11.0 to 1.  Pretty much all factory set-up.  No serp. belts being used here....factory originals only.  It could be a bad sending unit.  I think I'll change it out just so I know what I have here.  Actually, yesterday, we installed a new "pusher fan" in front of radiator, for added insurance when car is driven.  I have a 4 core, 4 row radiator in it now.  Well, this is where I'm at Ban617.  Any other ideas will be welcome.  Thanks for chiming in.    Don

[uscrichter]

I have had the problem with several big block restorations in the past and was the problem posted by 68z28 with the air pocket issue on both Camaros and Corvettes with big blocks and have successfully fixed the issue once by running the car without the thermostat and cap off for better flow, however on two accessions I literally had to raise the front end of the car 12" inches while purging the system so that the water could purge the air pocket in the water jackets and both times this procedure worked and for some reason have not had to raise the front of the car to purge small blocks that I have built. Good Luck!

[rich69rs]

I'm just throwing this out there as it happened to me.  My car started running hotter than its regular norm and started dying at a stop and being really hard to restart.  It usually didn't restart until it sat and cooled down awhile.  It turned out that the heat riser valve in the passenger side exhaust manifold had frozen shut. 

My suggestion is that you throw the heat riser valve out in the snow and replace it with a "donut" in order to avoid the very problem you mention.  I got rid of mine a long time ago. Only thing I do to compensate is a few more seconds at idle after starting cold.

Heat riser valves you get today from anywhere are junk IMO and you are just asking for trouble if you install one.