Re: 4.3 merc Cracked block, blown head gasket, or manifods? (LONG)
I did a compression test a couple weeks ago when it was hydrolocking. Unfortunately I didn't write the numbers down. They were all between 180 and 200. Mostly being 180. I haven't hydrolocked since I replaced the manifolds so that problem at least seems to be fixed. The oil then also appeared to be fine. It smelled like gas, but didn't look bad. After changing the manifolds and putting in rebuilt carb the oil went to crap. If I do have a crack, I guess it could have just spread after the engine ran more.
I had overheating problems a year ago so I am still not 100% convinced this is cracked block yet. I really want to do the air leak test on the cooling system. Any suggestions on how to plumb the pressure gauge and compressor to the port in my picture above?