The water pump could be new and junk
Run it with the cap off. If you get air bubbles all the time then you have a cylinder breach of some kind, or it’s air locked
I always run them 5 minutes before I put the cap on
CK5
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Overheating
- Thread starter RayzWorld
- Start date
Run it with the cap off. If you get air bubbles all the time then you have a cylinder breach of some kind, or it’s air locked
I always run them 5 minutes before I put the cap on
RayzWorld
Registered Member
Oh nice.. I'll try that and see what happens. Have you heard of the radiator cap being crap and it could be the cause of overheating?
Yes, if the cap goes bad it won’t keep pressure on the system. It doesn’t sound like that’s what is happening, but I’m also one of those “show me” types
The other radiator have a new cap?
RayzWorld
Registered Member
Im kind of the same way i need to be shown. Yes, the radiator does have a new cap and that didn't even crossed my mind to try and use it for testing. Great thinking .
Exactly what he is saying.
As I said, I had a new water pump be junk 10 years ago. It's even worse with parts now.
Look for flow or bubbles with the cap off.
Another difference water pump, PREFERABLY a stock replacement, non-shiny test part, is cheaper and less work than pulling the engine to go through it.
Shiny stuff doesn't mean that it is built to work hard..
Sorry.
my second post, block check will show if head gasket or something in combustion chamber is cracked. It is possible to get combustion pressure in a cooling system but no coolant in oil, very little to none coolant in cylinder/s
Also the correct direction. and if it is tight up against the rad it may not flow enough air. A 2 minute run shouldn't need a fan, nor build enough pressure to blow coolant out the top.
Shouldn’t, but if its working and so is the water pump, it should barely get off the tstat
Hey @RayzWorld are we sure the Tstat is in the correct direction?
I have dropped those in a pot of boiling water to make sure it pops open
RayzWorld
Registered Member
Okay, thank you. I understand what you mean. I got the chrome because there was too many parts that were already chrome so I just gave in with purchasing it. I'm really not big on chrome.
RayzWorld
Registered Member
I've put it in the correct direction, I've put a thermostat in before and I also watched videos to triple check that I was correct.
Wasn’t trying to be rude, but you’d be surprised how many dumb things I’ve seen here in the last 23 years
the 170° tstat in mine maybe 2 years old, temp would creep up and keep going. Well it would crack at 180° ish and not open till 200° ish. In AZ summer time an old gen1 small block can't survive with 200° tstat.
water temp 8° above opening temp
Not open
water temp 8° above opening temp
Not open
RayzWorld
Registered Member
I believe it because I've read it.Wasn’t trying to be rude, but you’d be surprised how many dumb things I’ve seen here in the last 23 years
I tend to agree with Wes on what he has suggested so far . For it to get that hot that quick and get the pressure that you have experienced so quickly , the first thing I would look for is combustion gases in the antifreeze/water . You need to eliminate the obvious first , you say you have addressed the radiator condition and thermostat , I would make sure that the electric fan is working properly , has sufficient voltage (through a relay with proper size wiring ) and enough air flow . Cooling is VERY dependent on proper airflow , I like to see at least 2600 -3200 cfm , a lot of the fans on the market may not flow but 600-800 cfm . Even if you have dual fans , you may only be moving 1600-2000 cfm , which may get you by in ok conditions .
Meaning what? It never gets hot up North?
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Also the correct direction. and if it is tight up against the rad it may not flow enough air. A 2 minute run shouldn't need a fan, nor build enough pressure to blow coolant out the top.
[/QUOTE
Correct direction is what came to my mind first on both water pump and fan.
Wasn’t trying to be rude, but you’d be surprised how many dumb things I’ve seen here in the last 23 years
Quit talking about me Bent! ; )
See if the rad hoses are being sucked in or squished when running, if you can find one with the spring in it they help.
In your picture the small diameter hose from the intake to the water pump looks kinked? Might just be the pic, but if it is a straight piece of hose look for one that is a formed elbow.
I am thinking you have a blown head gasket or cracked head. Like others have suggested,take radiator cap off and look for bubbles,(air) in the coolant. If engine has overheated in the past and good chance of a cracked head or even worse a cracked block. I had one over heat years ago and with the radiator cap off it blew coolant out that went higher than the hood.
skimmed through this - anyone checked the timing on that thing? and is are we sure it isn't running super lean?
someone once tried to mail a "custom chip" to me one time and made my 350 overheat in a hurry. noticeable increase in power, but the timing was WAY too much. even with the 160 degree thermostat, it would overheat and boil out of the radiator if i was hot roddin around at all... went straight back to the factory 180 thermostat and the factory chip with correct timing. no more overheating.
I saw a "think maybe i need to rebuild the motor" post a ways back... already going down that road without getting a correct big block radiator on it?
you mentioned already having the big radiator? I would flush that block with a garden hose as best you can and swap that bigger radiator in.
someone once tried to mail a "custom chip" to me one time and made my 350 overheat in a hurry. noticeable increase in power, but the timing was WAY too much. even with the 160 degree thermostat, it would overheat and boil out of the radiator if i was hot roddin around at all... went straight back to the factory 180 thermostat and the factory chip with correct timing. no more overheating.
I saw a "think maybe i need to rebuild the motor" post a ways back... already going down that road without getting a correct big block radiator on it?
you mentioned already having the big radiator? I would flush that block with a garden hose as best you can and swap that bigger radiator in.
RayzWorld
Registered Member
I ended up letting the truck run at idle and get to temp with the radiator cap off. It spilled out antifreeze for a bit and then stopped. I let it run for about 10 to 15min and the temp stayed at 160° with no issues and the return line was no longer hard as a rock. I changed the radiator cap and testing it for over heating at this time.
