Whats the easiest or best way to find out where I am losing coolant. It has dropped several times now so its not an air lock. Also no visible coolant on the ground. Motor is recent build. 383 stroker. Runs fine does not overheat. Thanks

Check the dipstick for a milky white color....If it's not a blown head gasket then coolant is seeping, from the intake manifold water passages, into the motor!

Also check the back of the water pump. My long water pump recently blew a backing plate gasket. I hadn't noticed any leakage on the garage floor either. But upon further investigation it looked as though it might have been leaking around one of the bolt holes on the backing plate because of the stain that it had left. Mine did not overheat either until it blew.

make sure the raditor is full. pressure test it. the leak will show up.
i bought a new rad. a couple years back, started to notice the fluid dropping to half full. couldnt find any leaks per say. so as a last ditch effort, i pressure tested it. the leak showed up. took it to a shop to fix it, come to find out the top half of the raditor leaked. the workmanship was less the perfect needless to say. sonny

Also check the back of the water pump. My long water pump recently blew a backing plate gasket. I hadn't noticed any leakage on the garage floor either. But upon further investigation it looked as though it might have been leaking around one of the bolt holes on the backing plate because of the stain that it had left. Mine did not overheat either until it blew.


If you're lucky, that's what it'll be. My truck did that and it took me awhile to find it. I kept topping off the bottle and it never overheated. You have to let it sit in one place and come to temperature so that it builds enough pressure to push out of the waterpump gasket if that's what it is. It winds up blowing it out going down the road so you never have a spot under the car unless it dribbles a little when you get home.

Do you have screw-in rocker studs?

Go to a parts store that rents tools and ask if they rent a cooling system/radiator pressure tester. It attaches to the radiator filler neck and you pump it up. The needle should remain steady. If it doesn't, you will see where the fluid is being pushed out of. Here is a link to a tester:
http://www.sears.com/shc/s/p_10153_12605_00946342000P?vName=Automotive&cName=Tools&Equipment&sName=Automotive%20Specialty%20Tools&psid=FROOGLE01&sid=IDx20070921x00003a

Let's talk about coolant level.... Many 1st gen owners overfill their radiators and think there is a leak. (I'm not saying this is your case .)
The proper coolant level for a 1st Gen is about an inch below the top of the radiator tank when you check it cold. (NEVER open it HOT!) If you "top off" the coolant level when it is cold, it WILL blow out when at operating temp. It has nothing to do with the engine overheating. It is simply thermal expansion. The excess fluid will eventually blow out and then remain at a consistant level after a few days of normal driving. If the level continues to drop after a few more days of driving, say to the point where the coils are almost exposed, then there is a problem.

If you have installed a recovery tank (using it as a closed system), and you are loosing coolant, then that is an entirely different situation.

Jb

Thanks for the ideas. I tried an overfill tank and a new radiator cap. That did not work still drops down real low after several 20 to 30 min run. I am going to try a dye in the system which can be detected by a black light. After that I will try some of the suggestions. Any other ideas or pat experiences welcome. Thanks again for responding.

I discovered I had a small coolant leak by having an oil analysis done. It was leaking thru the rocker stud threads.