Rebuilt engine overheating

If you read my posts in tech tips, you will see I had the same problem. I tried all the easy fixes:

a. refilled the radiator with fluid and hoped the air was out of the block
a. radiator cap replaced ( three times)
b. catch tank added on radiator overflow hose
c. radiator removed and inspected
c. engine block sealer added to seal any engine leaks


I had my mechanics at RATS take off the heads and it turned out the block was not smooth, and exhaust was pushing out the coolant. Several plugs had white stuff on them from water getting into the cylinders and there was rust from the water trails beteen the engine block and heads and on the passanger side.

Same symptoms, tempertaure gage would move toward hots,run it five or ten miles and I would have to add about a gallon of fluid. If I got on it ( ie high revs, I could empty the radiator out in a couple of minutes)

Anyways, the engine block was just milled. New head gasket. Engine is being put together now. I will know for sure if this repair worked later this week.

I hope yours is it is air bubble, timing or the need for a catch tank.

 

Sounds perfectly normal to me. All engines want a certain amount of coolant expansion space in the radiator (air bubble). If your car doesn't have a coolant overflow container, it will puke the excess out if the radiator is topped off. The temp gauge is the real indicator of a problem.

 

Exactly as KMCBOSS said. If you left the house with the radiator full to the top, the water expands. Especially after the engine is shut off. If it vented water down to about the bottom of the top tank, this is very likey normal.

 

Mine sounded angry too. In my case the exhaust leak pressurized and superheated the coolant. It even blew coolant out of the overflow catch tank.

 

is the thermostat installed correctly? is it the correct temperature t stat?

 

Another common cause of overheating like this are head gaskets that are installed backwards. If they are backwards, it blocks the water passages. It happens more than you would think.

 

when they rebuilt your engine they filled the radiator all the way to the top. it needs to be about a inch or so below the cap.

 

I had a similar problem as i have just finished my car last month.Freshly built 351w slightly tweeked i was advised for breaking the engine in to run a 4 core rad with shroud and i have an aftermarket flexi-fan.So far i clocked up 400 miles my temp stays around 205 no need for expansion bottle i think the 4 core rad done the trick i have been in stop and go traffic it did not boil over or overheat.regards javed

 

When I was younger I did this and the car had all the symptoms you have. I hope that is not the problem.

 

I don't see in your post what the temp gauge was indicating (before shutdown). If there is air in the system it will puke regardless of the engine temp upon stutdown. I had to jack up the front wheels to finally get all the air out when I had the same problem. That fixed 90% of the puking. A 16 lb. radiator cap cured the remaining 10% pukage.

Z. Ray
6s1117

 

Once you have run thru all of the usual and obvious "fixes" and they dont seem to help that much here's a possible solution for your problem. I have
done this a number of times. It's an old racers trick.

The radiator isn't working as effeciently as it could. Water must flow down
all of the tubes in the core. This means the water must flow accross the
top of the radiator to the other side. This allows the water then to enter all of the tubes in the core. The problem is: water is not reaching accross the full width of the core, hence cooling capacity is less than it should be.

To assure it does, it needs some help. This will take some help from your local radiator shop. If they take care of the local road race/stock car junkies this is a snap for them. They will have to remove the upper tank and install
a divider strip: a piece of "u" channel about an inch or so wide that goes
from side to side, above the top of the core.

This allows the water coming out of the intake manifold, and into the
radiator to encounter the divider. This will ensure water flows along the divider to to the other end of the radiator and then into core tubes.
This gives full flow coverage to the entire radiator core. Suprisingly,
back in the early 60's, some of the big block performance Fords had this
installed from the factory.

Hopefully this sheds some light on your problem from another perspective.
Good luck on your finding and correcting the problem.
Regards, shlby66.

 

get a new clutch. I had a 390 that did this and put a new fan clutch and it fixed the problem.