Well, I did find a leak on the new engine and is becoming a pain in the butt. The long water pump bolt which also holds the lower alternator bracket has a drip. Would this be due to a bad water pump? I've tightened it to the point where it's pretty tight, and it still leaks. Any suggestions?
drain the block ... let it dry... take the bolt out.. and put some sealant on the threads of the bolt and put it in the hole.. tighten it.. and let it dry.
You don't have to drain anything if you let it cool down completely and use "Gasket Maker" by "Loc-Tite" on the threads and under the head of the bolt. Just pull the bolt out after the engine is cool. It won't leak much if at all. Coat the threads and under the head of the bolt and put it back in.
much better. it shouldnt leak, but a bit, i'd coat the threads good, then stuff it back in, you can wipe the excess off, it should seal good.
Oh YES! that gasket maker is a lot better on straight threads than teflon tape. It can't get into the coolant either. It just stays on the threads and will seal a lot of pressure. It also acts like loc-tite and won't let the bolt vibrate out. Will teflon tape do that?
i wouldnt use teflon tape for bolts.. maybe a water sensor or something.. but not on a bolt the reason i said to drain it.. you dont want water in where the bolt hole is.. otherwise the sealant wont seal properly. you want to have dry threads.. inside the hole and on the bolt when you seal it
Why is sealing the threads necessary? You have a gasket between the waterpump and cover and another between the cover and the block. I would think you could remove the bolt completely and not have leakage. It sounds like a torn or cracked gasket that is allowing coolant into the area around the shoulder of the bolt.
some of the bolts go all the way into the water jackets. the water is not leaking through the gasket, but runs out the threads. if that's what the problem is.
Is this something with later blocks? I just went out to the garage and air pressure-checked all the front cover/waterpump bolt holes in my '70 302 bare block and none of them went into the cooling passages. They are all blind holes.
The Gasket Maker doesn't need dry threads. It will seal no mater what - even in oil. Some of the holes go into the water jackets - just like screw-in rocker studs. The added benifit is that it acts like loc-tite which is something that some thread sealers don't do. I have used it to seal transmission leaks in industrial transmissions. A very useful product that only requires a film that is .010" thick.
Again, is this something that is only present on later blocks? I have never experienced this and I have had a lot of small-blocks. My current 302 does NOT have any of the holes entering a cooling passage.
i was also told to put antiseze on the whole bolt. it will keep it from leaking and rusting. the guy that told me this was changing a water pump and had 3 bolts break off in the block. he said he has had that happen a few times. i have noticed before that the water pump bolts are always rusty when i pull a pump. that is what i am going to do on my new engine ...frank...