Over heating prob. ideas coments please

[816allen]

When i took her to get legal maybe 10-15 min away jumped on highway most of the way jumped off drove maybe 5 min and she did great once i left, went straight on the highway maybe 5 min she jumped up to 230 240
Jumped off real fast turned it off.........
Cooled down drove home flushed entire system, everything and put new 180 stat in and new antifreeze of-course .
Now i drive it on the highway maybe 2-3 min and shes doing it again wtf hoses all have springs in them so they cant collapse water pump aent leaking but do ya think its going out.....?
Rad looks great...



Also I turn on the heater/defroster i guess, just a slight hint of heat coming out.
I'm also not really feeling a good wind from it or the fan below or on top is that normal?
I know shes old but ya never know so I'm asking,I tried search but really didn't get answers like i want...
Please any info or ideas ya got would help me out thanks!

Also I did burp her real good so i doubt it has air in it...

[Eagar1]

Could be lots of things, what engine? How old?
I have actually seen impellars rusted away so bad they didnt pump, and the pump didn't leak, you could have an impellar spinning on the shaft. You could have total blockage in your radiator, block or even heads.
Pics help too =)

[816allen]

Sorry my bad heads been worked before i bought ....I was told and have no proof....
Its a 250 Straight six not sure what year because it has a egr on it so I'm thinking it was out a new model than my truck mine is a 65

[816allen]

I dont have any new pics but here is some when i got the truck...

[Eagar1]

The EGR may be your problem, as if it is not set up properly it can lean out the engine causing it to run hot, especially if your carb isn't set up right already, and you could have the timing off, etc etc.

You may also have a blown head gasket, which you can check by leaving the radiator cap off while the truck heats up and see if you can see bubbles, or you can even get a tool that can sense exhaust gas that you hook to the radiator.

You can even have a cracked block but that usually puts water in the oil.
If the engine is well worn, or has been over bored, the cylinder walls can be too thin, and the water heats up faster than the cooling system can handle.

If the head was worked on they could have not installed the right head gasket, or put it on wrong blocking the proper flow of coolant.

Just some other points to ponder.....

[816allen]

Well today I burped it again and once it got to about 210 215 it stopped bubbling and was starting to just rumble out the hotter she got...
I have the right intake for it i guess ill get some gaskets for it and carb and slap it on see if that helps man I hope it aent a blown head gasket never changed one and not sure if i want to or if its worth it....
Wouldn't it smoke at all with a blown head?
Also carb needs to be replaced or rebuilt its loading up if i floor it...
"not in gear "

[wbr775]

well if you blow a head gasket you would be losing coolant. did you flush the radiator thoroughly? is there anything blocking air from going through the radiator? how old is the water pump? just because it doesn't leak doesn't mean it is good. mine was doing same thing. it is a 283. replaced water pump fixed it right up. just saying. im not telling you it is a water pump.

[816allen]

Ya i was thinking its a old water pump for sure wouldn't hurt to replace it good or bad atleast ill be at ease down the road and ya i flushed it real good took my time cleaned all the hoses and where they clamp on took the stat housing sanded it down to bare metal taped it then painted it.....
The guy before me flushed it because of over heating but only put water back in for some reason....
Ill do the water pump and intake back to stock see what she does hope for the best ya know....There's some good shows coming up but i gotta use the highway to get to them so I'm praying this does the trick!

[MacAttack]

Be careful you're not just chasing a bad indication from the coolant temperature sensor. Is this radiator over-flowing into the catch bottle or out on the ground?

[816allen]

ya it will throw a lil in the overflow and even more if i lift that tab.....why what ya thinking

[MacAttack]

Well - I always go after the simple stuff first.

Is this an all-of-the-sudden thing?

Is this a highway only deal - or all the time the engine's running?

You've replaced the radiator cap?

And again, when the engine over-heats, is it puking violently into the catch bottle?

Too much air/exhaust gas in the cooling system is a bad thing and it shouldn't be too hard to track the source down. These sixes are pretty much indestructible, but if you do have a warped head and the block isn't hurting, it's not that big of a deal to pull the head and have it checked out.

Case of beer and a couple of husky buddies will handle that in a weekend.

Mac.

[816allen]

Ive only had the truck for a lil bit but once I started to really drive it farther than around the block it has over heated I have a gauge going to the stat and motor it could sit in my drive way and over heat......
The rad cap is for sure aftermarket but no i haven't changed it i was thinking about that also...
No its not puking violently in the over flow
I'm gonna take her for a short 10-15 min or so ride see how she does i did get more air out of her last night i think.
Thanks guys for keeping up with this thread and helping me out with ideas on pinpointing the problem with this thing!

[MacAttack]

Do the simple stuff first - cause you end up replacing all the little gear anyway when you rework the head and they're not big expenses. Remember, most of the time it points back to the radiator on the straight sixes - or the water pump.

Is the radiator the thin 2-row core?

[816allen]

OK drove it to work today no highway and never really got over 200 deg but it was kinda cold out too....plus short drive so IDK

[Corts60]

Is your temp gauge electronic? I would check the engine with a temp gun or even a thermometer when she starts getting warm, just to be sure it isn't your gauge or sending unit. One time, on my Nova, I chased my tail trying to figure out why it kept overheating and then I shot it with a temp gun and it said 185!

It turned out to be a bad ground which was screwing my factory gauge all up and making it read wrong.

[Chevy Fleetside]

Looks like it has a new sender on it. if so they don't work with the older trucks. Mine did that with the new 350 and new radiator. I wold make it get hot and somehow open the cap very careful like. I guess I have had lots of practice on it and can do it somehow. I was able to put a thermoter in the radiator to find out it was fine. I put a resister on the wire so the gauge and sender would be on the same page. Even if you go get a cheap gauge and hook that up just to make sure.
The only other thing I can think it would be is the radiator. If the core is clogged up it will be fine on the streets but as soon as you get on the freeway the temp will rise fast. No amount of flushing will cure that that I know of.

You could also get one of these

[apachedaddy]

Does it have a clutch fan or direct drive fan on it?? Mine had a clutch fan on it and it went out, i put a driect drive flex fan on it and sloved my prob.

[816allen]

Even if the Rad is flushing out clear water it still could be clogged? Dam I figure it was good.....



Ya i was thinkin about buying one of those caps but 40 bucks turned me away....




Its just got the stock belt fan.......

[816allen]

MacAttack is Hooking me up big time with a nice Rad Cap so lets see if that helps you never know the crap after market one i have on there now may not let out pressure.......Lets hope for the best!
Thanks MacAttack I owe you big time!!!

[Frizzle Fry]

Only overheating on the freeway sounds like timing too advanced to me. If you are cruising at hwy speed and step on it do you hear pinging? Also you say you get a stumble when you step on it "not in gear." This could indicate an overall lean condition which would will contribute to overheating. It could also just be a bad/insufficient accelerator pump squirt.

[Frizzle Fry]

BTW, I did a head gasket on my 230 in an afternoon by myself. No big deal. Also, it is possible to have a blown head gasket without a coolant leak on these. I replaced mine for a compression leak. But it didn't cause overherheating...

[SCOTI]

Originally Posted by 816allen

Even if the Rad is flushing out clear water it still could be clogged? Dam I figure it was good.....

Since the radiator is a series of tubes that allow air to flow over them for cooling, it's VERY possible that a portion of the radiator (a portion of those tubes) is clogged thus limiting the heat transfer area available while still allowing flow through the remaining unclogged tubes.

Stock 'small' 6cyl radiators were not generally regarded for their abundant cooling efficiency. Add several blocked passages & 'uh-oh' . . ....

[816allen]

Ya makes since I'm gonna find a rad shop and see how much they charge to get it boiled and gone through.........
On a good note i can still drive it on side roads all day long and only get to 200 deg on stat and up to 220 on the motor so I drove it to work today man since i got tags last week I cant stop driving this dam thing I'm hooked to it!
Don't know how much gas i have or how fast I'm going but I'm having fun lol

[Corts60]

Originally Posted by 816allen

Don't know how much gas i have or how fast I'm going but I'm having fun lol

That's the spirit!

[816allen]

A lil LATE update sorry guys my computer has been down.....
Well i scored the free rad cap wasn't it but looks and works good thanks allot MacAttack i still feel i owe ya buddy!
My buddy had a new 60s style rad out of a camaro and man i got it in there and she stays coooooooooool 50 bucks well spent!
Only thing i had to do is but a new top hose and a lil bending and cutting and shes in there.