I have a 302 engine, and currently it has a coolant leak at the thermostat. I think the reason it is leaking is because I did not get the thermostat to line up right, and it is being pinched, I had a really hard time getting that thing to stay in the middle. Does anyone have any suggestions on how to get it to set right. I am getting ready to take the manifold off and stand it up so the thermostat stays were I put it. If I were to do that could I use the old intake gaskets, or could that couse a leak.

Also even with the cooling system full, my truck takes forever to warm up, and the gage will read at the cold line of the normal band but it wont stay there, it will move just a little in either direction, and the air blowing out of the heater will be just barely worm. Is this normal, Could I have a bad thermostat? It is new and it is supposed to be a 95, but it is much colder than that I think.
I have never owned a vehicle this age, and I have never owned a carberated vehicle, could this heating problem just have something to do with it's age.

 

any truck will take long time to heat up if theres a air bubble in the heater core side or just idling. my question is did you change the ratiator fluids when yuo did install and if so when you filled it up did you run the truck with radiator cap off to check for fluid movment? as fo thermostat theres usual a small recess for it to sit in when properly installed if theres no recess I put a lil rtv on the edges of the gasket to keep it center and the gasket holds the thermostat.

 

triple check to make sure its the right size. i had the same kind of problem but on my 4 banger import. sorry to hijack the thread here but dungeon . . . please elaborate what you are talking about with running the engine without the cap. i know it has something to do with it possibly not having the right pressure? am i right? if so, what now cause i did the exact same thing and i have the same exact "symptoms" as Mr. Finch . . . so in essence, its not a hijacking lol

 

if it did slip out of center then coolant is going around it could cause the slow to heat issue. I use contact cement to glue my thermostats in place and then I glue the gasket to the housing further holding the stat in place apply a thin film of rtv and you should be good to go. Remember the pellet goes toward the engine. And since you did pinch it in the housing make sure the housing isn't warped. I broke a housing one time by letting the stat get pinched.

 

Stupid me. I forgot about using the sealer, I don't normally use it so I forgot that such a thing exists.
When I first got the truck ans it had the other engine in it I checked and you could not see any flow. but if you disconnect the upper hose, it sprays coolant, and the antfreeze and water were mixing so I am pretty sure there is flow.
felixr
You made me think, I dought it is the problem, but it is possible. Here is the problem. When I got this truck it had the 255 v8, the po put on a Edelbrock performer 302 intake manifold so he can put on the Holly 4 barrell carb. When I say it is the edelbrock performer 302, all I mean is that is what it says on the top, I did not find any part #, and I do not even know if it is realy for the 302. I am currently using that intake on this engine, and I was wondering is he put on the wrong goosneck, or if I did get the wrong thermostat. I dought it is the thermostat, because the 255, 302, 351, and 460 use the same ones, wright. But this guy loved to take apart cars, and I was wondering if this goose neck could be from a different moddel or even make. If so will I beable to use the one from the efi intake.

Also of the things that I took from the 255V8 the timing cover and water pump were some of thoes things. Are the water pump and timing cover for the 255 the same as the 302. From what I have sean the only difference between the 2 engines was the bore, stroke, and intake ans exhoust ports.
Anybody have any other ideas. Since my radiator is now about half full, I will get a new gasket and use sealer and see if that helps. But I had the slow warm up problem even before I was low on coolant.