'74 Mav, 250 I6. Just replaced the waterpump (check my other post - !@#$!! help?)... I'm getting water in the oil. No idea where from. I picked up a new head gasket, and figure what the hell - the motor has like a million miles on it, and the gasket was only $22. Any tips on replacing the head gasket? Any comments/suggestions? I'd like to run a compression test on the motor first, but to do that, I'd have to wait until like 7pm tomorrow eve.
It sounds to me like you drilled a hole to deep in the engine when you tried to fix your water pump problems. I "think" you might have drilled a wee bit to far and.........have........ruined................................................the motor. There, I said it.....somebody had to break the bad news to you.
Sounds like Craig may be right. Unless there is a crack in the block allowing coolant to flow where it ought not to, you may have been a little too aggressive with the drill. We don't know what your budget constraints are, but another motor may be your best, if not only, option. There are decent used ones out there. I found a 250 locally with only 60,000 miles on it cheap from a private owner. If you have a decent wrecking yard nearby that uses the Hollander system, they can find one for you if they don't have one themselves. Of course, there's always the 302 swap option.....
j.m.o. you said 1 million miles, in my messing with motors over the years a motor with that many miles it will be like opening a can of worms. everything you touch will need to be replaced. if you pull the head that would be a good time to do a valve job. if you do that when you put it back on you take a chance of blowing the bottom end with the new compression. the list goes on and on. putting a head gasket on a bad block would be $$$ in the wind. as wes, suggested a different motor would probley be best...frank...:bananaman :bananaman L.T.N.G.
Well, I feel the least I can do, is yank the head, and look, right? I'll pull the water pump back off... anyone have a diagram of the head, head bolts, tightening pattern, or anything like that?
If the 250 is ruined, I'm definetly going 302. Northern Auto has a stock rebuild kit (everything minus heads/crank/rods) for $200. Can't beat that with a stick. I just need wheels right now, and if I can get another 2 weeks out of the 250, I'll be set.
If there was no leak prior to your waterpump installation, it's absolutely pointless to change the head gasket. Why go through the headache when you are almost certain the waterpump issue created your leak. That is where your attention needs to be focused. There is no reason to change a head gasket if the only reason is mileage. Head gaskets do not wear out.
Don't waste your time changing the gasket. A couple of reasons: 1. You are going to need an exhaust manifold gasket as well. I can just about guarantee that you will break off some of the exhaust manifold bolts in the process. This means that you will need to drill those out...or take the head to a shop and have them removed. 2. If you don't do everything correctly when re-installing the head, the new gasket will probably leak. Now you are back to where you started. Honestly....all I see is more problems with the road you are heading down. You need to definitley find out what the problem is before you do anything else. Measure twice...cut once.
So what would you guys recommend? Just pull the water pump off, then put it back on? I was thinking that pulling the head + pump would let me at least try to find where the heck the problem is... if I did nail an oil galley, shouldn't I be able to see it, then? How do I know the head gasket didn't blow, when it was run about 35 miles with no water? The few times i have gotten it to crank, it was blowing some white smoke... *sigh* I may just disassemble this motor, and throw a 302 into it, anyway - just to have a fresh motor, and none of these problems. I guess that's what happens when you take a 200k+ mile engine, and try to work on it.
That's your option. The white smoke is usually indicative of coolant in the combustion chamber. the plugs should show this also. Does the smoke have any trace smell of anti-freeze? Sometimes if the amount being dumped is great, you can smell it in the exhaust. If you have access to an exhaust analyzer, and you very well may not, an old trick is to put the probe into the radiator filler inlet and see if you have any CO readings. If you do, this is usually indicative of a blown head gasket. Obviously, you are getting coolant into the chamber. Bottom line is that there may be more problems with this motor than you should be investing much time and $$ in. It gets to a point that you have to cut your losses.
Pulled the head. Lots of good news. The head gasket was busted. Right along the number 1 cylinder, broken in 2. Also found something nice about the #1 slug - it's got about a 1/8" chunk missing on the side of it. You can see right past the rings. Yay. 302 definetly on the way.
A little late, but this may help for future problems with drills. I was working on my friends 66 mustang, replacing valve covers, when I misread the torque specs (10 years ago, don't flame me ) and overtorqued the valve cover bolts, and snapped one off into the head. GREAT!!!! Instantly I yelled "DAAAAAAAD!!! He came out with his drill and proceeded to drill out the bolt. Only problem is he drilled right on through, and into the water jacket, and crumblin almost all of the bolt support material around the bolt. Well, we broke out the jb weld, and stuffed a bit down into the hole we just made, then stuck the bolt in the hole, and formed a new surface around the bolt for it to thread into, we then broke out the razor blade and began to trim. After we were done, it looked oem, and 10 years later, no problems!! I was going to suggest stuffing jbweld into the hole, but it looks like you have bigger fish to fry, good luck!!
Well, I'm gonna do what I can with the 250. I kinda need to get to work tonight, and ah, this is the only car right now My Camaro is running again, though, if I can just get it insured/tagged today
jeremy, That JB weld trick may work for a valve cover bolt, but you could probably run a valve cover with a bolt missing and suffer little ill effects. I would not use the JB weld trick to create any bolt hole that would require healthy torgue or sealing.
