Found A Crack...
Thread Starter
Safety Car
Joined: Aug 2000
Posts: 3,909
Likes: 26
From: Clymer PA
Found A Crack...
As I was porting the heads I found a very small crank inside the intake runner. It's a pretty small crack (approximately this size "-"). The good part is that it isn't a crack that goes into the water jacket. The small crack is located where the rocker arm stud is screwed in. With the rocker arm stud removed, you can look down the hole and see a little bit of light due to the crack. I honestly don't think it's that big of a deal, but I could be wrong. Am I correct in thinking that I can take the head to my machine shop and have it welded and smoothed down?
Surely I wouldn't have to junk that head because of this... :( But if I do, that will just give me a good excuse to get a nice set of heads :)
Surely I wouldn't have to junk that head because of this... :( But if I do, that will just give me a good excuse to get a nice set of heads :)
Melting Slicks
Joined: May 2000
Posts: 2,125
Likes: 9
From: Crescent City, CA
Re: Found A Crack... (bence13_33)
Bence
That should not be a problem, just use sealer on the stud.
Watch out for the bump (head bolt boss) in the exhaust!! If you take too much off there the head will crack when you tighten the head bolts.
Terry
That should not be a problem, just use sealer on the stud.
Watch out for the bump (head bolt boss) in the exhaust!! If you take too much off there the head will crack when you tighten the head bolts.
Terry
Le Mans Master
Joined: Aug 2000
Posts: 9,662
Likes: 7
From: Semper ubi, sub ubi
Cruise-In VI Veteran
Cruise-In VII Veteran
Re: Found A Crack... (bence13_33)
Bence,
You can get the crack welded, it won't hurt the head at all. I'd suggest taking it to a competent machine shop, and let them check the heads out. They should be able to pressure check the heads and find any cracks you can't see.
It is cheap insurance.
You can get the crack welded, it won't hurt the head at all. I'd suggest taking it to a competent machine shop, and let them check the heads out. They should be able to pressure check the heads and find any cracks you can't see.
It is cheap insurance.
Melting Slicks
Joined: Aug 2001
Posts: 2,833
Likes: 15
From: Southeast La
Re: Found A Crack... (bence13_33)
Bence.....
Don't do it!! :nono: Oh my God for the sake of St Jude. I had a cylinder welded one time in the exact same spot, and what a mistake. The shop I took it to charged me an arm and a leg and I had to take it back to them three times! When they got it right, it cracked in two when I was running out at the track, melted the whole block. A piston cracked and slung a rod through the block, threw oil all over the track, causing the car I was racing to crash into the wall.
Of course, this is all :bs I just wanted to give you a reason to buy some new heads. :D
Don't do it!! :nono: Oh my God for the sake of St Jude. I had a cylinder welded one time in the exact same spot, and what a mistake. The shop I took it to charged me an arm and a leg and I had to take it back to them three times! When they got it right, it cracked in two when I was running out at the track, melted the whole block. A piston cracked and slung a rod through the block, threw oil all over the track, causing the car I was racing to crash into the wall.
Of course, this is all :bs I just wanted to give you a reason to buy some new heads. :D
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Re: Found A Crack... (Jvette73)
You might want to be careful about welding that head....
I have an ASME & AWS certified weld shop, and we weld everything from racecars to spacecraft. There's no qualified process by any recognized welding authority for welding cast iron. Reason for this is that cast iron gets extremely brittle when you weld it, and tends to crack out. The welded joint does not have the strength of the parent material, and an inferior weld repair results.
There are people out there who have success at welding cast iron. It's more of an art than a welding science, and specific filler material is used with a TIG process ("Heli-Arc"). It's not something that a regular machine shop would have the capability to do. In the entire metro Denver area, with all the contacts I have in the welding business, I know of 2 people who could pull this off with success, and I'm not one of them...
If the crack is in a non-structural area and not in the water jacket, you might want to consider stop drilling it and using some JBWeld rather than actaully trying to weld it.
I have an ASME & AWS certified weld shop, and we weld everything from racecars to spacecraft. There's no qualified process by any recognized welding authority for welding cast iron. Reason for this is that cast iron gets extremely brittle when you weld it, and tends to crack out. The welded joint does not have the strength of the parent material, and an inferior weld repair results.
There are people out there who have success at welding cast iron. It's more of an art than a welding science, and specific filler material is used with a TIG process ("Heli-Arc"). It's not something that a regular machine shop would have the capability to do. In the entire metro Denver area, with all the contacts I have in the welding business, I know of 2 people who could pull this off with success, and I'm not one of them...
If the crack is in a non-structural area and not in the water jacket, you might want to consider stop drilling it and using some JBWeld rather than actaully trying to weld it.
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
Re: Found A Crack... (bence13_33)
Take it to a shop and have them magnaflux it...it may not be anything more than a surface scratch, or there may be more cracks than just the one you can see...most cracks are not visible to the human eye until it's too late. Also have them mill the head for straightness while it's in...the entire process is usually only $40 - $50.
