Double check your macinist work !!!!

[jon rand]

Well I finally got my 73 MOTION camaro ready to holeshot down the road, so I thought. Well I finaly got the motor assembled tranny gone through, had it all put together boy did it sound good. I ran the car in my garage for about 2 hours on jack stands, just to make sure it didnt over heat and ran the trans through all the gears, every thing good. Well it was finaly time, I shut this beast off, took it off the stands, got in and here we go so I start the car and it turned over kind of hard and then fired, I got out to double check for any leaks and such when i saw a bunch of water from the header to the rear end @%%^^&& I said. I shut it off pulled the plugs from that side cranked over the moter, water shot out the #3 hole.I pulled the head and the one valve guide i had replaced leaked, when the shop presed it in or out they cracked the head,not only did it crack the head but the cilinder hydroliced, bent the rod and cracked the piston around the pin. So after three years of waiting i guese it will be a litle longer, this sucks! So just a warning, double check all macine work no matter how good your macinist is supossed to be. And by the way the macinist said I didnt do that! so i'm stuck with the bill.

[T Billigen]

Should have major parts magnafluxed as a precaution, most places would recommend this just to make sure what happened to you would be covered!

[jon rand]

They were magnafluxed, aparently before he put the guide in. I also had .040 shaved,valve job and hot tanked. I might just set up a booth at Norwalk Super Chevy an show his work if I cant get him to fix them. I bet that woud be good for business!

[robber6910]

Jon, I've noticed alot of machinists won't put any guarantees on a block if it's more than 10 yrs old. I have been shopping around for a place to work a 427 block I purchased. Alot of guys just don't want to mess with it. My assumption would have to be that if something happens to the block, they don't want the headache of trying to fix it or giving you some kind of restitution if it is unrepairable. You should take the block to SC, show everyone what they did to it, and how they screwed you over. You should also report them to the better business bureau. Good luck. Rob

[COPO PETE]

Been there...done that!!!! After pulling the motor on my orange COPO after spending hours to install with no chips or wrecking finishes on bolts, I now have a new engine guy who pre runs the motor and breaks the cam in on outer springs only to make sure it's right on. We then dyno it with many pulls to 6000 rpm (7000 in the ZL-1 case). When it goes in the engine bay, it's READY!!!!!! Best $350 bucks I ever spent!
Peter

[jon rand]

Sent my head to another shop to be welded. They are going to pressure test it so i know it wont leak this time. Pete thats whats bad all that work making everything look perfect, down the drain.

[Stefano]

You hit the key note, it is mag. and pressure testing. A reputable shop should know to pressure test big block heads after a new Guide(s) has been pressed into the head.

[fpcopo]

Hi Jon, sorry about your trouble. It is unusual for a big block head to crack by the guide. However the exhaust guide goes into water and they sometimes leak there which is what might have happened to you.
You said you were sending the head off to be welded. Did you verify that it is in fact cracked by the guide?
If it is cracked and you do get it welded, make sure the machinist resurfaces the head and does another valve job. It won't take much if welded right but things move around alot under that much heat. Now, you were very unlucky if the head was NOT cracked but only the guide leaked because usually it just fills the muffler up with water and blows it out when you start it but doesn't hydraulic the cylinder. Was the car steaming when you first ran it? If a guide is leaking it usually steams bad when you run it out of one side.
Believe it or not, you can fix this by getting a 6 pack of stop leak pellets from the GM dealer and dumping them in. We put them in all new engine jobs for just this reason. They won't hurt anything but really stop the leaks. They used to put them in all new GM cars at the factories to stop possible warranty problems. Frank Payne

[YENKO DEUCE REGISTRY]

Frank;
Have you ever had those pellets deteriorate the heater/radiator hoses? I tried them once on my Trans Am, and they worked great for about 5-6 months. Then all 4 hoses (that were fairly new) developed splits in them within the same week. When I changed them, they had those pellets all gooked up inside. Maybe I put too much in, or the wrong type, but curious as to your experience.
Thx,

[jon rand]

It was cracked, had it magged again. It also bent the rod I checked with a dial indicator thar cylinder was .095 below the deck and the rest were .020 below. but I got a new piston and rod done today so I am on my way.