Worried about my EGT probe...

[TurboOmni08]

Do you guys think this weld is going to crack?! I didn't know how else to do it and keep the probe in the right place.

http://i26.photobucket.com/albums/c133/TurboOmni08/DSC00548Medium.jpg

http://i26.photobucket.com/albums/c133/TurboOmni08/DSC00546Medium.jpg

[1FastCSX289]

Cast iron is pretty hard to weld to and have it stick. Why didnt you tap the manifold and screw the fitting in?

[shelby zed]

looks like it would hit the other side.

[Stinkbox]

i angeled mine in the other direction, towards the turbo inlet and didnt weld anything on just tapped it on an angle. still a tight fit though.

[mo' parts]

i had one in that location once, worked well. i didnt weld it though, i tapped it, only prob. there is its on an angle and not very thick there. you only get a few threads, so be careful not to strip it out.
as for welding it, depending on how to did it, it should be fine. like many others, i have found #3 runs a little hotter than #4 for some reason, thats where mine is now.

[TurboOmni08]

Well, I got it with the hole already drilled, it was too big for my Autometer probe. So, I could have got a brass modifier, or pluged it and drilled somewhere else, but the welding seemed to make the most sense. Everyone says to be 1in from the head, which is exactly where it is. The weld seemed to stick well, I have never done welding before (after I did this everyone at the show was like "damn, picked a hard first welding project!") so I think it turned out rather well for my skill level. I had to grind it down a bit a few times because it got sloppy. There is a lot of weld build up there, and I cut a few shallow grooves in the iron to help it adhere. It was a mig welder I believe.

Is there any way to test if it will crack? Heat it up with a oxy torch a few times and let it head cycle?

[mo' parts]

Well, I got it with the hole already drilled, it was too big for my Autometer probe. So, I could have got a brass modifier, or pluged it and drilled somewhere else, but the welding seemed to make the most sense. Everyone says to be 1in from the head, which is exactly where it is. The weld seemed to stick well, I have never done welding before (after I did this everyone at the show was like "damn, picked a hard first welding project!") so I think it turned out rather well for my skill level. I had to grind it down a bit a few times because it got sloppy. There is a lot of weld build up there, and I cut a few shallow grooves in the iron to help it adhere. It was a mig welder I believe.

Is there any way to test if it will crack? Heat it up with a oxy torch a few times and let it head cycle?

i think it will be fine. many people have welded on the cast when making their swingvalves and they seem to hold up. not sure if i would heat it w/the torch as you may make it crack. typically its best to have the whole thing heated before the welding, too much heat in one spot can/will cause a crack.
im still a welder in training, so my welding advise is to be taken somewhat lightly. lol
im sure someone else w/more experience can prob. help better than me.

[Birddog]

im still a welder in training, so my welding advise is to be taken somewhat lightly.

Preheating and a long slow cool down is key with iron. Stick usually gets better penetration in my experience, I have done mig repairs to manifolds that held up for as long as I kept the cars the repair was made on it just wasn't pretty..

[Clay]

yup, pre-heat and post-heat, then wrap it with insulation for a slow cool.

[mo' parts]

there is a local guy i had do some welding on my manifold, he was in the air force and did ALOT of work on the stealth bombers. he told me, usally they drop it in a barrel of sand for cool down, but informed me i would be fine. matter of fact, it was an egt bung i had welded a couple years ago..

[Clay]

Ive heard of the sand thing, but never seen it.

[shelby zed]

ive done the sand thing when welding differentials, still warm hours later