Broken water pump bolt

[Cliff. Elford]

Problem: The water pump bolt {one of five} that bolts on at the 10 o'clock position {71 Z} has broken off deep inside the block.

Why is this bolt 3 1/2 long? Is this length necessary to get past the aluminum block? Is the block not aluminum? Has anyone had the experience of drilling this bolt out at this depth? Is it possible to tap the hole as it enters the block and installing a new shorter, fatter bolt in the new tapped threads? I am looking for enough pressure to keep the gasket from leaking, {or blowing out altogether} the first time I drive through Baker, California when the temp outside reaches 120 degrees. Right now there is no leak because I applied a bit more pressure than I normally would to install the new water pump. Is there any chance that block sealer used with the new coolent would help keep that gasket stronger? Novice that I am I hate to try to dig that old bolt out myself. Suggestions would be appreciated.

Thanks, cliff

[RandyC]

Don't worry.....I am restoring a '71 that I have owned since Jan 76. Since then I have lived in several places the most recent (and lengthy) of which is the "moderately temperate" Southwest in the Phoenix area. I twisted that bolt off about 130K miles ago and when I pulled the engine and looked in that area everyting was STILL sealed without any late model adhesives. I think that if you broke 2 adjacent bolts you might be in trouble but for that particular one........my experience is you are fine as long as you watch the temps and keep it under 7500 rpm!

Randy in AZ

[2ManyZs]

The only reason I can think of that the bolt is so long is that it probably passes thru the water passage inside the block. Would it be difficult to remove, darn right, if it broke of that deep it will be. Should you remove it? It's possible at some time it will deteriorate to the point it could pose a problem. As far as drilling and tapping the outer section I suppose you could just to make sure you are applying some pressure to the pump. I think I would just use some good sealant for now, if it gives you problems then try something else. Somewhere in the future you may need to do some block work so then you might be able to have a machine shop drill out the broken bolt. I don't think I would try this myself, no sense in doing it without the right tools. And no the block is cast iron, so it wouldn't be as easy to mess up as an aluminum block, so for now I think I would leave it as it is. Just my suggestion.

[Daniel]

Boy reading the troubles on this fine website sure takesme back down memory lane!Broke bolt 10 oclock.Yeap!I ran one like that for years.I put the extra sealant on the gasket.Never had any problems.If I may offer a trick for future use.Any time you try to remove a bolt/nut that has been in place for a long time.First try to tighten it aLITTLE don't force.Then as you remove the bolt/nut.Remove a little then run it back down some.Continue this until removed.This forward motion clears the threads of crap that the reverse motion loaded into the threads.It turns easier and won't break them off! Have Fun! Daniel

[byunique]

The bolt is 3.5 inches long because it first had to make it's way through the timing chain cover. The cover is a good 2.75" at the point which you are describing. The depth at which the bolt screws in the block is probably not much more than 5/8 of an inch.

If you were to pull the timing cover off, you would probably see that the bolt broke toward the bolt's head, so that the majority of the bolt would be sticking out of the block. You could then use some channel locks to pull the rest of it out.

I had the same thing happen to me, and I felt much better once I replaced the bolt...one of those confidence level things....

[Royce]

I don't have any experience with this bolt, I replaced my waterpump when the motor was out last. But I do have experience replacing the timing chain cover. If you are thinking of taking the timing chain cover off to get to that bolt you sould realize that the timing chain cover is sandwiched between the head and the oil pan. In fact if I remember correctly there are a few bolts that attach the cover to the head, you shoud take off the cam cover and look to be sure. I was able to get mine out by droping the oil pan just a bit and carefully removing from the pan gasket and head gasket using a metal putty knife. If you do damage the head gasket or the pan gasket you may be able to repair it with liquid gasket maker/sealer. However, if that doesn't keep the oil in the engine you may need to replace an entire gasket.

[Cliff. Elford]

Gentlemen: Thank you for the input. I have decided to replace the water pump without that bolt installed. New coolent and a can of Bars Leak along with a few prayers. I think it work just fine. {hope, hope} cliff.