radiator overflows

[Bill 49]

Does anyone have any thoughts as to why the radiator on my 440 would still be overflowing? I thought it was a blown head gasket so I pulled the head and had it checked, got new gaskets from Lavoy and followed the rules for install. It seems to really "gush" when it trys to start and just falls short of actually starting. No water in the oil and it actually runs pretty well. The radiator cap was weak so I put the one from my truck on but it still leaked a bit from the overflow line. Didn't make it work hard since I didn't want to make things worse. Is it possible for the water pump to be acting up, I did notice that the belt is pretty loose. Thermostat was tested and is working. Antifreeze was tested for -35 before it got cold here in Wisconsin. If it wasn't the head and it's not the water pump what else should I consider.

thanks

Bill

[Lavoy]

Did you have the head magnafluxed?
Lavoy

[Bill 49]

Lavoy, not sure what magnaflux is but the shop I took it to tested the head under pressure and vacuum, they said the valves and guides were good. This a pretty reputable shop but I can call them about magnaflux.


Bill

[Tigerhaze]

Bill-

Magnaflux is a process that is used to determine whether there are microscopic cracks in the cylinder head. Iron oxide particles (either in solution or dry) are placed on the part to be tested. The part is then paced into a magnetic field and examined with UV lights. The particles flux around the cracks and can be seen using the UV light.

[Lavoy]

That would seem like they should have found any leaks then. Did you use anything on the head gasket when you reinstalled it?
Lavoy

[Bill 49]

Lavoy, I was afraid you would be asking me that, the short answer is no. The question is what should I have done? I can pull the head in about 45 minutes so that may be the next step. If so, can I reuse the head gasket or am I better off getting a new one.

Thanks

Bill

[Pammark]

The head is only half of the collant system. What about the block? There might be a crack in the cylinder wall or small pin holes in the sleeve.

Drain the coolant and adapt an airhose to the radiator cap inlet with maybe a rubber stopper and presurize the coolant jacket. Pull the spark plugs and listen for air leaking through the spark plug hole and oil filler. A leak as bad as you seem to state should be heard. If you can not get your ear to the sparkplug holes, listen through a rubber hose.


Mark

[Lavoy]

I use Copper Spray a Gasket or Kopperkote, Hylomar would work too. I have had ZERO luck getting a metal head gasket to seal without using something. I did one engine 3 times for just exactly the same problem you are having. Last go around, I coated the head, gasket and block, no problems since.
Lavoy

[jdemaris]

? I thought it was a blown head gasket so I pulled the head and had it checked, got new gaskets from Lavoy and followed the rules for install.
Bill

You might want to get your coolant checked for CO intrusion. It's an easy check and will tell you for sure, if there is a crack anywhere letting combustion gasses into the coolant. It just takes a minute and is done with a test-strip of paper.

[Pammark]

I learned a trick from an old mechanic. I have done this many times and never a fail yet.

Get any type spray paint in a can and spray both sides of the head gasket until wet on some cardboard. Put on engine and torgue it down. Just be careful not to have so much dripping paint as to plug small oil holes.

The big question is, what color to use.


Mark