Running hot

RDubya · Poncho Master!

Running hot

RDubya · Poncho Master!

Anyone got a pressure tester? I see Princess Auto sells for $100, but i don't want to invest that for a one time use.

eeluddy · Uber Guru

Ask one of the local garages to pressure test it for you. Is there any anti freeze in your oil? Start the car when cool with the rad cap off and let it get to temp and see if there are any gases or bubbles indicating a head gasket or cracked head. How old is your radiator? Has it ever been recored?

Ghost Post · Poncho Master!

What are we talking here, the Firebird w/ a crossflow rad?.
And what's 'using up' antifrz mean as far as the amount lost?.

Have you let it run w/ the cap off and topped up the system after confirming the stat is open by feeling heat in both hoses?.
Also with the engine running and stat open, looking in the rad filler have you visually seen coolant flowing by?.

With cap on and engine hot from a drive, after shut-down pop the hood then look and listen as the pressure built up may be enough to cause the leak and help you find it?.

If you can't find anything and think it's an internal leak, do you know someone w/ a scope or emission testing equipment that can 'sniff test' your cooling system for hydrocarbons?.

Good luck!

-- Edited by Ghost Post on Thursday 22nd of July 2010 12:45:07 PM

RDubya · Poncho Master!

I'll try checking with the rad cap off to look for bubbling when i start it up. I also need to pull of the oil cap and check to see if i've got any water vapour there. I hope it isn't the head gasket.

Beaumont4008 · Uber Guru

If it was getting into the combustion chamber via a head gasket, your exhaust would puff a liitle white. I test for that the old fashion way. I put my hand over the exhaust pipe until my palm of my hand gets moist and then give it a lick, if it taste sweet then its antifreeze into the combustion chamber. I know the dumb back yard mechanic way. But it works.

73SC · A Poncho Legend!

Hoping it's not internal but looking that way, I'd bet it is the intake manifold gasket.

Remember I have access to a good 5.7 from a GTA.

RDubya · Poncho Master!

Thanks for the tips guys. Ray i have a feeling i've got a big project ahead, i'm pretty sure it's going to involve ripping this engine apart. I know that i've got a LOT of work ahead if it is the head gasket. As strange as it sounds i am interested in doing this to get a look at everything and learning as i go since it's the first time i've taken apart an engine. This way i can replace valve cover gaskets while i'm at it. Also do some clean up of the engine and see if there are any other problems developing assuming i can tell what they are. Like so many say, the only way is to learn by doing so here's my chance. I say that assuming it is the head gasket, i've got a feeling it is the more i do my research.

-- Edited by blacktransam on Thursday 22nd of July 2010 03:10:02 PM

-- Edited by blacktransam on Thursday 22nd of July 2010 03:17:55 PM

73SC · A Poncho Legend!

Just changing the gasket may not be enough if it is leaking. Coolant leakage is a large cause of main bearing or rod bearing faliures which often ruin the crank as well.

Ghost Post · Poncho Master!

Cam bearing failure can happen easily too if the system isn't drained properly first and any coolant runs down inside the lifter area when intake manifold is removed..

Be sure you have the problem absolutely diagnosed before ripping anything apart!.
Again how much coolant loss are you experiencing?.

Good luck w/ everything!.
~

RDubya · Poncho Master!

Pete the other day before changing the thermostat i drove the car to work, about 40km. The resevoir went from full down below add. So while it was hot i topped it up to near the full mark. I drove home and checked, it was full. I thought what harm would changing the thermostat be so i went ahead and did it. When i drove to and from work in the country it ran around 220 degrees. Yesterday, which was a really hot day, i just drove in town for a few minutes and it got up to 240 +. I ran it out of town to the first concession and back only because the temp guage was still up there. Got home and it hadn't gone through any coolant, resevoir was still full. I didn't check it again after it cooled down. I'll try to take a look tonight. I was surprised the other night coming home that i didn't lose coolant. And it hadn't gone down when i went to change the thermostat.

grande jim · Guru

If your not losing any more coolant you could have a bad thermostat..wouldn't be the first time that happened!!

RDubya · Poncho Master!

Jim, yeah i guess i could have bought a bad one. Once i check for a head gasket problem i should pull it out and test it.

66 Beau · Poncho Master!

Sounds like you had air in the system after changing the heater core and had to top up after the themostat opened & you circulated out the air. I am surprised you didn't have teh same prolem again after changing the thermostat.

Check the thermostat by putting it in boiling water. It should open before the water gets to a boil - or if you have a thermometer, you can measure exactly.

An old mechanic friend told me that the majority of cooling problems are due to a bad cap. Replacing it costs $10. A pressure tester is $100.

455gto · Poncho Master!

http://www.youtube.com/watch?v=hUzOTnsWImI&videos=b7QdzvNpK68

Randy this is a great video for you. Shows everything to look for when you have a overheat problem.

dualquadpete · Canadian Poncho Superstar!

any chance you installed the new T/stat up-side down??? That will do it too, no coolant flow. Pull the oil dip stick [JIMMY] & see if theres any coolant in the oil????

grande jim · Guru

I think the point here is ...As Pete said....diagnose the problem first, run all necessary tests then start fixing (Exactly) whats wrong....Guessing and throwing parts at it can be a good learning experience..but it can get very costly as well. Been there! Done that!

RDubya · Poncho Master!

I've done some troubleshooting. First i opened the oil cap and took a look. No water vapour on the cap. No discolouration on the dipstick when i checked it. I tightened a connection to the overflow bottle. I went ahead and picked up a rad cap, cheap insurance. I started the car and moved it out so i could observe the tailpipe. No sweet smell/taste, and no white smoke. I drove it for a few minutes down the street in traffic and it heated up. I was stuck behind a few cars and the temp climbed. Once they got out of the way, the temp dropped down since i had open air. I couldn't see any debris in front anywhere blocking the air coming in. I had checked the fan and it was working but i don't think it was turning fast enough. I have an inkling its the fan.

87 player bird · Poncho Master!

A lot of these cars have an aftermarket toggle switch to control the electric fans.

4SPEED427 · A Poncho Legend!

Silly question, but did you put in a GM / AC Delco thermostat? It sounds like I'm brainwashed but I have had no luck with any other brand in a GM and perfect success with the GM parts. I have had a number of customers who have had the same experience.

RDubya · Poncho Master!

It's an aftermarket thermostat. The car went to down to around 220 once i had no one in front of me in traffic. It had got up past 240 just before that while in traffic. I've looked in the service manual trying to find what to do about diagnosing the fan but can't find anything. Is there a fuse for it in these cars? Is it all mechanical? The fan is actually turning so is there even a problem with it? There's no rad leak but could it still be the problem? I know i'm a real amateur at this and having a hard time figuring it out. Thanks for bearing with me.

Since this post i've drained the oil and there i had no antifreeze come out, just the oil.
-- Edited by blacktransam on Monday 26th of July 2010 06:38:16 AM

-- Edited by blacktransam on Monday 26th of July 2010 12:22:52 PM

RDubya · Poncho Master!

I checked in with the garage i took the car to before they closed for the day. Car is running at 190. Cleaned inside and outside of the rad, did some levelling of the thermostat housing, told me it wasn't sitting flush, replaced the coolant and it's good to go. Cost a bit but i'll pick it up in the morning and be able to hopefully enjoy the car the rest of the summer without anything major going that can't wait to be fixed until the "off season".
Thanks everyone for all the suggestions to help out.