I just put a new waterpump, new thermostat, new rad cap and new coolant in the car, and its still over heating. The coolant is not flowing from the overflow tank to the rad and is causing the car to overheat.

 

You did actually put coolant in the radiator itself and not just the overflow bottle correct?

 

Sure seems like it.

 

It doesn't matter if anything from the overflow bottle is going to the radiator. That's not going to be your source of over heating. I would double check and make sure the coolant level in the radiator is where it's suppose to be. If it's not where it's suppose to be, their is probably a lot of air in the radiator.

 

Start the car let it run untill its warm and make sure your fan is kicking on(I had this problem with my old Trans Am It ate fans like nothing due to a bad switch....

Check that problem before you spend more $ and I would also check your coolant level in the radiator before you get it warm and let it run with radiator cap off....

Make sure its not puking coolant out when starting or shutting off.

 

The rad is full and the rest of the coolant I put in the overflow bottle, for some reason I don't think the thermostat is opening, I just put a new one in today and it's still not opening. And yes I did put it in the right way.

 

pull the thermostat out completely and see what it does. If thermostat isnt opening that means your bottom radiator hose or waterpump isnt working properly. Did they give you the correct pump Some pumps turn clock wise and some turn counter clockwise

 

Are your fan coming on? If not then that could be the cause.

 

Make sure you get a fail safe thermostat when they fail they fail open not closed.

 

You can test the thermostat in a pot of boiling water.

 

How long after starting does it over heat?

What condition are the hoses in--Does lower hose collapse from the pump suction?

Fan(s) & relay(s) good?

If it gets hot while driving-- air dam in place?

What temp is the stat & what temp for fan(s) to come on?

Sorry if you've checked these, but that's all I could think of!

 

I'd check all of your hoses for cracks and crimples 1st. Next I'd do what the other guy suggested and put that t-stat in a pot of boiling water and see if it opens up at all. Then if those things don't work it's possible you were sold the wrong water pump. All the work you did for your I just did for my car back in March and my doesn't overheat anymore.

Also, what pressure rad cap do you have? 15# or 16#?

That makes a difference too, if it's not holding pressure. If you've got fluid in your reservoir & in the radiator then the real problem is abit deeper. I would double check and triple check everything and that's the best advice you can get for free. Take it to a shop and you'll get raped.

 

The car heats up about 10 to 20 minutes after start up while in park idleing. When i rev the car the lower rad hose does collapse, the rad hoses are original to the car. The stat is 195 degree and the fans come on at 220 which is stock. I drove it less than a mile today and the car was up over 220 almost into the red. We put the GM dex-cool, the orange stuff into the car, would it have been a better idea to go with the green coolant?

 

if the lower hose collapses then there is a restriction. either the radiator is plugged or the thermostat isnt opening. remove the thermostat and try it again. it would have been better to put the green stuff in it. i hope you flushed it very well before putting dexcool in it as it doesnt mix.

 

Come on now guys. I see that there is a senior members in here. Have you checked the tech articles on the main page? You may have a problem with your timing. Yes it can cause over heating. Review the page that I have provided you..... https://www.thirdgen.org/overheating

 

alright mister senior member there. when in the hell have you ever seen the timing being off cause a hose to collapse. it doesnt. and. if the timing is that far off it would run really bad. two. it will over heat while idling. heck the timing can be advance 20 degrees and still not cause it to heat up that much while idling. the cooling system has a restriction. period.

 

ruberbanman126--

Before the lower hose gets hot, is it firm, or is it more soft & mushy?

If it's soft & mushy and collapses before it gets hot, IMHO, replace it.
Also, IMHO, I would get the correct size spring insert if it doesn't come with 1.
The spring will help from collapsing. A spring in an old hose will result in the spring coming thru!!

My reasoning--
I had a '75 Camaro, Bigblock. After just a year, the lower hose started the collapse thing. I put a new hose & spring in it-- no hose collapse!
I also needed a new rad, but never got it--shoulda had a pressure test......

 

 

Wow, such hostility. What crawled up your tailpipe? A smog probing instrument perhaps?

 

no people like you calling senior members. it doesnt matter if someone has 10000 posts it doesnt mean they are good mechanics. and we have been giving him sound advice. timing?????????? come on. i have been a mechanic for over 30 years. and he just now told us the bottom hose was sucking shut. RESTRICTION! not timing.

 

If the timing is off, you would know.

Dont worry about 86, He seems to have some fetish with post numbers.

 

I would bet money that the small line that runs from the overflow tank to the radiator is plugged up. It will look like bran or fiber. Something of that consistency. You'd need to take the line off and flush it out in a sink until it runs clear. Once that's fixed, your overflow tank will work as it's supposed to.

 

Well, from , I learned something!!

Thanks Reid! That's something I have never heard, but will keep in mind!!

 

Also - the radiator cap controls the overflow - as the pressure builds in the radiator, the cap is 'opened', allowing excess fluid into the overflow. As the pressure subsides, a vacuum is created, sucking the excess fluid back into the radiator.

Same as canning veggies - boil the jars, pressure builds forcing air out of the tops, as they cool, vacuum is created sealing the lids air tight - the screw on tops are only put on afterwards to keep that vacuumed seal from getting disturbed.

That why a bad rad cap can cause overheating - can allow excess pressure to escape too early or too late.

But I agree with the lower hose - replace and get the right spring for inside it to keep it from collapsing.

 

What do post numbers have to do with anything.

 

Looks like someone has a bad memory but if memory serves right you and your posting history proves this, you do. Its in this thread others if I recall.

Keep spamming that smilie, Just goes to show who deserves it.

Now please before you turn this into another drama thread, end it.

 

Actually you want to put the screw caps on loosely so that the lids do not fall off becuase if they do you have to redo them and you may end up with nasty dry fruit if you pressure cook them twice.

 

wow this has gotten to be a good one.
1. it was overheating before you did all this.
2. you replaced most of the stuff but not the hoses.
3. you have the lower hose that is sucking shut with rpm's
now. when you were replacing the coolant and all that did you look into the radiator to see if there was buildup on the fins? one thing you can do is remove the radiator cap and start the car. see if the coolant is flowing from the hose that goes( engine to radiator) the small one below the neck. and also that it is flowing thru the radiator fins. you dont need the cap on for this test. and even if you dont have the cap on it should not overheat. the timing can be off for this test as well. now as the car is starting to warm up keep feeling the upper hose. when the thermostat opens it should get very hot. now if you can feel the radiator near the top hose and near the bottom hose. how cool is it. the bottom hose should be warm and the fans should be on. rev the engine some and see if the hose collapses. you can take the overflow bottle off the car and it will not overheat so dont worry about it right now. what you need to be concerned with is coolant flow.
now before it started overheating the first time what was the last thing you did to the car. did you change something? add something to the engine? or is this something that has been happening over time and you just tried to fix it.

 

one92rs, Ive heard of a spring that inserts inside of the hose to prevent collapse. Would that be wise or just a waste of money?

 

all lower hoses should have that since it is the suction hose of the system/

 

One thing that I would definitely do is find a member that has a cable that can connect a MemCal to a PC. The objective is to change The BIN settings inside the EPROM. Our factory fan turn on setting is set at 220* or 225* for the ECM controlled fan. That is too hot but our engines where designed to run that hot just for a more complete burn of the fuel to reduce emissions. But lf course that temperature affects performance and engine life. So what I did was chance my factory settings from 225* to 183*. As for the temp switch that is inside the passengerside cylinderhead, remove that one and Install a tempswitch that is rated around 180* for the second fan. If had the equipment, I would do it for you (reprogram the MemCal) for free, but I do plan on buying everything to start programming blank EPROM's. If your instersted, and get the cable, would you want me to change the settings?

 

1. You need to replace the lower hose atleast. If it collapses it is bad and nothing else you do is going to fix it. You need one that has the spring. I had a very similiar/ weird issue in the past that the temp would go back and forth from 195 to 220 going down the road and stay at 220-230 sitting. It was the hose expanding and contracting. I replaced it with one with a spring and no more problems since. The spring works as it makes the lower hose more rigid.
2. Dexcool should not be in any vehicle in my opinion. It clogs alot of parts. My friends Bazer had dexcool and he had to replace everything, the heater core weighed 3 times as much as a new one due to the dexcool, breaking down and sludging up everything. When I pulled the heads on my 2000 SS Camaro the coolant jackets around some of the cylinders were clogged with the same sludge from the Dexcool. Every since I first found the problem when I see a car using Dexcool I look at the rad cap and it is gunked up with the same sludge and has flakes in the coolant. Go back to th green stuff. Once my truck is out of warranty I am getting rid of the Dexcool.

 

You need a reverse spinning water pump on the car.
I bet you used a older model water pump off a older model engine.
I just bought a camaro about aweek ago and had the same problem.
It was the water pump it was spinning the wrong way and would not cool the car.
Thats why your hoses are collapsing.
I hope this info helps..

What year car is it 1992?

 

I have heard that too much coolant and not enough water will make it run hot because the coolant retains the heat. I was told to drain the rad a little and add more water, should i try this?

 

Check the casting numbers on your water pump.
Im 99% sure you have the wrong water pump on the car.

 

not sure if anyone has said anything about the fuseable link that takes care of the cooling fans. my buddies 91 did the same thing. but only did it ever so often. then one day it over heated and it wouldnt start. just to think of something, the fuseable links are at the battery. just hanging off of a junction block off to the side of the radiator support.

hope this helps a little

 

personally, i would never use the spring inserts. a radiator hose should be able to hold its own, if it collapses its time for replacement. period.

imho the inserts should sit on the self next to bars leak and alumaseal.

you said the hoses are original? well 20 something years later, its time to replace them. i bet another expensive set of acdelcos would last another 20 years. my upper hose is an original gm

 

To be honost with you, you should drain the whole system and clean it out. There is a fluid that is used to clean out a cooling system. Not sure what its called. But be careful though. Dont let any radiator fluid or the clean leak into the street because 1, it illegal and 2. you dont want to contaminate the environment (plus coolant is very sweet because of the Dextrose and is very poisonous to animals). you should have your system at 50/50.

 

WOW!!! This is my problem exactly. My sons 1986 Z28. Just put in a new 350 Long block. I have doneeverything you have done. I am now going to replace the hoses. Might as well only thing I haven't done. I am going to replace the temp coolant sensor/sender and guages as well. After that I think someone said the intake manifold because I don't have rear ports on my Holley street dominator. I ahve too much money into this car now to stop. I'll even try the timining. But Thanks to all for ALL the advise.

 

Hold on bro. You got a 350 in your 86 IROC? The 86 only had 305's. There were about 50 350 TPI's made for the 86 but they were never sold to the public. Not verified but I read it somewhere on a IROC website. Im guessing that you have a TPI system. If so, you'll need to reprogram your MemCal to run 21 lb injectors. Also here is what you'll need to change
1. ESC Module to a 350
2. 350 Knock sensor
3. 19 lb injectors to 21 lb injectors

To get better info, follow this link (very important)
http://tpiparts.net/305_tpi_to_350_tpi_conversion

 

never mind. I see that its carb.

 

And I noticed its a Z-28, not an IROC.

 

Drill a 1/8" hole in the thermostat base to allow air to escape when you fill the system...you probably have an air pocket in there that will not allow hot coolant to reach the thermostat and open it up. I had the same problem on my Trans Am and a hole in the thermostat fixed it!

 

Yes buy pre mix 50/50 to make it easier.

 

4Playta-Where do you Drill this hole? Where on the Thermostat? Thanks

 

anywhere on the outside edge