Do you have a real mechanical water temp gauge on it? If so does the water temp seem to rise and drop often? I have had more trouble with getting all of the air out of 5.0's than any thing else I have ever worked on. Did you drill a small hole in the outer ring of the thermostat? It helps. Try parking it up hill and crank it with the rad. cap off and let it warm up a couple of times. I also put a small valve on one of the openings on the intake that I can crack and let the air out of. That works good also. clint
Thanks for all the info and input guys very help ful keep comin on all the tips! Ive done everyone so far exept putting a lot of effort in getting all air out. ive had to refill coolant because of leaks and on second run my bottom radiator hose blew becasue of bad clamp. tomorrow ill try with getting it up hill and running and taking off rad. cap. a couple times. I did not hear about drilling hole in the t stat. where would i put it? Just anywhere? how big and what is that for? My dad is becoming paranoid that its an internal problem rather than something we can fix externaly. One reason that could be true is that the head gasket is either facing wrong way or the hole isnt big enough ( Hole near the front of head ) I was told that a lot of people acidently plug that with gasket and it makes it over heat. There is also another weird thing we found today, theres a hole next to the header on the front of the passenger side head and one on back drivers side head that air is coming out of. Is this exahust, some emisions thing that i have to plug? Thanks again!
The holes in the heads are for the thermactor/smog pump.You need to plug them.Best way is to tap the holes and screw in pipe plugs to seal em.As for the T stat...drill a 1/8 th inch hole at the 12 O'clock position on the face of the T stat.Not in the gasket contact area though, below it.It allows air to escape while filling the cooling system.As for your electric cooling fan...Its not big enough.You need to pull 3000 cfm if not a bit more 1200 cfm is not adequate for a stock 302 let alone a bored out one.Especially if you are running the stock radiator.Get a bigger cooling fan regardless of the overheating issue.If you are in doubt about the head gaskets...pull the heads(when in doubt...check it out) you will need to to get the smog holes tapped and plugged anyhow.Good luck.
It threads into the head and plugs it. It also has internal threads for use with bolt on accessories on the front of the head.
