[78w72]

im sure florida makes a big difference compared to most places, im in iowa & although we have terrible winters & mild spring/fall... the heat of the summer can be almost as bad as florida... mid 90's & terrible humidity but luckily it doesnt last that long during july & aug.

as much as the divider plate clearance is mentioned, some members on here say they never clearance the plate & have big gaps like your .200 & dont have any cooling issues. so its hit or miss & the rest of the system like tune, fan/shroud etc play a big part in how a car cools. i would imagine your new pump will help though.

nice looking 79, my 78 is a black W72 4 speed hardtop.

[nUcLeArEnVoY]

Originally Posted by 78w72

im sure florida makes a big difference compared to most places, im in iowa & although we have terrible winters & mild spring/fall... the heat of the summer can be almost as bad as florida... mid 90's & terrible humidity but luckily it doesnt last that long during july & aug.

as much as the divider plate clearance is mentioned, some members on here say they never clearance the plate & have big gaps like your .200 & dont have any cooling issues. so its hit or miss & the rest of the system like tune, fan/shroud etc play a big part in how a car cools. i would imagine your new pump will help though.

nice looking 79, my 78 is a black W72 4 speed hardtop.

Yeah, in FL the humidity is almost year round. So I'll take any measure I can to keep this car near 'stat temp in all conditions. Point is, an inferior part with a big clearance was on the car, and that is a known issue with Pontiacs, so it's the first thing I tackled. These temps I told you about are WITHOUT AC, mind you. Pretty sure it's not an airflow problem. Using stock shroud, stock 19" 7-blader, a brand new Hayden 2747 HD clutch... heck, I even got some weather strip to seal the shroud against the radiator. At idle speed, a piece of cardboard will get sucked against the condenser. Pretty sure it's just insufficient coolant flow at low RPMs. Also using the original overdriven 6.5" AC water pump pulley.

And thank you so much! I've had 'er for almost a year and a half now. It's got its hangups like any 40+ year old car that hasn't been completely gone through, but it presents well. Like a step or two above a driver, if you will. Got any pics of your '78 to share?

Right now I'm a little concerned, though. I pulled the old water pump a few days ago, and like a dumb*ss, I didn't drain the cooling system thoroughly enough. Not only did I make a huge mess when the water pump came off, but as soon as I removed the two long 3/8" bolts that marry both the water pump and timing cover to the block, I saw a small coolant leak spring and dribble down behind the timing cover where it meets the block, right at where the coolant passage is on the timing cover-to-block gasket on the passenger side. I'm hoping it's only because I undid those bolts, and when I put on the new pump and snug everything back down, it'll seal it back up. I figure that undoing those bolts caused the tension/pressure from the intake-bypass connection where the donut o-ring and draw bolt is to overcome and unseat the timing cover toward the top just enough to spring the leak. It only takes .003-.005 for water to seep through afterall.

Really don't want to have to pull the timing cover and re-gasket it. If it does seal back up when I cinch everything down and refill with coolant, I'll do an oil change just in case before I start the car.

[78w72]

the a/c condenser can restrict flow, one member recently had a thread about overheating when he installed the condenser, said it was ok before that. but these cars stayed cool from the factory so the a/c parts shouldnt be related to your overheat.

i did see your post about the timing cover leaking. if the gasket is newer or in good condition & isnt ripped it should seal back up when you tighten it all back down.

heres a pic of my 78, 400 4 spd. no a/c.

[nUcLeArEnVoY]

Originally Posted by 78w72

the a/c condenser can restrict flow, one member recently had a thread about overheating when he installed the condenser, said it was ok before that. but these cars stayed cool from the factory so the a/c parts shouldnt be related to your overheat.

i did see your post about the timing cover leaking. if the gasket is newer or in good condition & isnt ripped it should seal back up when you tighten it all back down.

heres a pic of my 78, 400 4 spd. no a/c.

Hmm, perhaps. Id hate to have to sack the AC tho.

Interestingly, I don't know if they're related but I noticed that the heating up in traffic or idle has occurred after any time I rev the engine to 3500-4000RPM and cause a belt to chirp that I've been dealing with. It could've been an issue the entire time I've owned the car, but I'd have never known since I VERY rarely wring the car out. I drive it like a granny and I'm delicate with it.. ill usually shift at 1800rpm. So I looked around and noticed my power steering pump was installed years ago without the .250" rear bracket spacer, causing it to bow downward and misalign the pulley so maybe that's the source of my chirp. Also using same width belts on alternator and PS pump even though the PS pump should be slightly wider. Anyway, like I said, I noticed the heating up occurs after that belt chirps... can you think of ANY relation? Maybe once the belt chirps, it starts slipping thereafter even though I can't hear it, causing the water pump not to flow coolant as well?

Man, is your 78' a beaut! I bought a 78' SE clone without t-tops back in 2008 site unseen off eBay and it was a disaster. Turned me off from old cars for years while I had a 2010 Camaro. In that time I developed a taste for the 79-81 body style and ended up getting this one last year from a guy a bit up the road. Went to go look at it first lol like a smart person.

[78w72]

i dont think a slipping or chirping p/s belt would cause overheating since the alt belt also drives the pump pulley separately. sounds like you have checked all the right things, see what the new w/p does & go from there.

thanks. it had the common gold decals but since it has a red interior i chose the silver/red bird that came on white & silver cars when it was repainted. a friend of mine has a 2010 rs/ss camaro with a mild cam & lots of bolt on goodies, its a nice modern car but not as fast as it should be for what it is with modern technology.