I totally understand. I have so much to do that I can't seem to get anything done!

 

I was chasing the threads of the bolt holes in my new short block when I found one of the holes by one of the water inlet ports had rusted through into the water jacket. The other 3 holes surrounding the water ports has a lot of rust in them, but did not poke through. I guess I'll have to use thread sealer on that punched-through hole, like the lower head bolts, and hope it holds.

I'm now worried about what other areas might be rusted thin. Before machining, the machinist did a visual check and found no cracks at any of the usual places; in the lifter valley, between the cylinders, and the main web. He did find a broken bolt in one of the other hole around the same water port, which he removed and fixed. This engine saw pretty severe neglect.

The original engine I want to replace has over 198000 miles on it, and I noticed something recently that might indicate it's time to do SOMETHING. The oil pressure gauge needle would jump around when the engine is idle, and stabilize when I start driving at higher RPMs. My impression is that maybe the oil pump is not generating steady pressure at low RPMs, and only gets steady when it is run at higher speeds. Does this sound right?

 

Is it possible to use studs in those locations? I would try and do that if it was possible.

 

I guess it's possible; I would probably get a stainless steel threaded rod and cut it to size.

 

Making threads in stainless is not fun. If you can find a stud at a good hardware store, I would pass on that idea.

 

Not what he said, you can buy threaded rod, stainless steel, mild steel, aluminum, brass, at hardware stores, or W.W. Grainger, McMaster Carr.

 

I misread it, thanks. But stainless is still a bitch to cut threads in.

 

I had a guy not too long ago who bought a stainless steel bolt kit for his Ford Windsor engine. Of course about 90% of the bolts were the wrong length for the front of the engine. I was able to clamp them, cut about an inch more threads using a die and then trim them to length. It wasn't easy but it wasn't terrible either. These were ARP bolts but I bet there are other stainless alloys that would make that about impossible. I had nothing to lose. I used some very nasty smelling tapping oil that came from my grandfather who was a pipe fitter. Good stuff.

 

Yes, I was thinking of looking for some length of stainless threaded rod. The thread is 5/16-18, and looks like my local Ace hardware store has some in stock.

I tried cutting some threads in some stainless rods once, and just messed it up royally, so I finally gave up and bought some from eBay.

The question I now have is, will putting a rode in the leaky hole work better than a bolt? The stock bolt has less than 1/2" of thread engagement, and I think I can run my tap about 3/4" in. My thought is if I use the stud, I can apply more sealant or teflon tape to the longer piece of stud that goes into the hole, hopefully resulting in a better seal.

 

I would feel more comfortable with a stud that is somewhat permanent. I am certain there is some loctite product that is designed for that purpose.

 

I got the thread sealer intended for the lower head bolts whose holes are opened to the water jacket. Shouldn't that work for the water pump/front cover bolt?

 

It turns out the ARP thread sealer is teflon paste, which I've used before in home plumbing repairs. I might feel better using teflon tape instead.

Based on your advice, I got a 5/16-18 stainless steel threaded rod which I will cut to length and install into the holes surrounding the water ports going into the block, with plenty of teflon tape to seal the hole that had rusted through.

I just hope that there are no other leaks in this block.