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Discussion Starter #1
I called my machinest yesterday and he said to come down, he wanted to show me something. I came down there today and he explained that he was putting the new pistons with the new rings in the bore and when he mic checked # 6 it was .010 to large, and it turns out that # 8 was also .010 overbore and there was a stamp that said .010 GM on the top of the oil gallary next to numbers 6 and 8. He said hes never heard of that, all the rest of the cylinders were std bore. He had to sleeve the cylinders and make them std bore again. Is this a good way to fix things? has anyone ever heard of a block like this? To my knowledge it is completely stock from GM. the stamp has GM on it. It is a Hencho en Mexico Block as well.
 

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You forgot to put a burito in the gas tank!

Never heard of anything like that, what where the pistons at?
 

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Discussion Starter #3
i brought the pistons down for him to mic sure enough 6 and 8 were 4.010 and the rest were std. numbers 6 and 8 were also diff pistons the rest were hencho in mexico.
 

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Dont know what to say.

Never heard of GM doing such a thing.

I would just go with a .020 over bore and forget about the whole thing, but sleveing the cylinders is fine too.
 

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That doesn't surprise me at all really. Depending on the cost to sleeve the two cylinders I would think about boring all the cylinders (what ever it takes to get them clean and all the same size). If the sleeving is done right there is nothing wrong with it.

To do it right it is not cheap if I remember right. A new set of pistons could/should be cheaper. Sounds like you are running cast pistons anyway. They are VERY inexpensive.

Just something to think about.

Royce
 

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Discussion Starter #6
The thing is my machinest took the liberty upon himself to sleeve it. w/o calling me. He wont give me a price quote on it either, How much money would you guess for two cylinders to be sleeved? I have talked to a few people in my town about this machine shop (Bell and Gains) and they all say its a good place.
 

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Wow, that sucks that the machinist took it upon himself to just sleave it without calling you. Also weird that he won't give you a price either! I would proabably have gone with the .020 on the two cylinders and .030 on the others.
I hope everything works out ok for you.
By the way, what is it that you're building?

Rock on and God bless...

Señor
 

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overbore

I would say he bought you a sleeve job if he did it with out your permission first. It would have been more realisitic to have bored them all out to 4.02 or 4.03, in my estimate. Sleeving isnt a cheap way to fix anything. Sleeving those two cylinders probably costs as much as to have bored them all out to the above specs. At least aroud here it does.

I would also get written price on what it would have cost to bore it out to the previous mentioned specs, and get a hard price on the sleeve job. Dont forget that both jobs are going to require new pistons as well, and if it comes out that boring all 8 out to 4.02- 4.03, including pistons would have been the less expensive way to go, I would only pay him what ever is the lesser amount of the two. If he wants to squawk, tell him to explain it to your attorney.
 

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Bore

I know positive that GM did make quite a few .010 blocks in the early 70's. A few years ago this was encountered and the parts manager at the Chevy dealership did a direct contact with GM parts division. GM had quite a few blocks that were machined incorrectly and rather than scrap a bunch of blocks it was cheaper to go to .010 pistons. 1973 350 engines seemed to have a higher number. If you encountered a ring problem with any of the engines you could get GM rings but cylinder problems and you would have to bore to .030. I encountered this problem in 1985 on a 73 impala. I was amazed at finding .010 pistons and had never heard of it from the factory untill the research was done and the information came straight from the horses mouth. So GM does do it rather than to scrap blocks.
From my management experience with GM and rule of thumb on any auto related business you cannot repair a customers vehicle or in your case the block without your permission, signed or verbal. Without your permission on ANY repair, and you do that repair then you just ate it.
 

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You need a new machinist for two reasons.

He didn't check the bores to start with.

He didn't advise you of the cost of sleeving before doing it.

Mention a lawyer. Crooks love that!

tom
 

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.010

First, i am with Tom you need to find another shop. I would never do something like that with out getting the go-ahead from the customer. Plus he should have given you the other options, like boring to the next oversize,,, alot more cost effective then sleeves...

Second, all those crazy oversized engines do exisit. I was told one time that the come-back engines from warrenty work are fixed and put back into service. And they only repair the problem not rebuild the total engine.

Keith
 

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k-star said:
First, i am with Tom you need to find another shop. I would never do something like that with out getting the go-ahead from the customer. Plus he should have given you the other options, like boring to the next oversize,,, alot more cost effective then sleeves...

Second, all those crazy oversized engines do exisit. I was told one time that the come-back engines from warrenty work are fixed and put back into service. And they only repair the problem not rebuild the total engine.

Keith
"dang dude, why you going so slow?"

"oh gotta break in my #8 rings again."

K:rolleyes:
 

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Tom hit the nail on the head and it was my first thought. Why didn't the machinist measure all the bores to start with.

In any case it may be cheaper for you to pick up another block and let him keep the sleeved one. It really depends. Like I said above if the sleeve job was done right there is nothing wrong with it. I would be HIGHLY upset if my machinist ever did anything like that without calling me first. He should make suggestions and give you options it is supposed to be up to you to make DECISIONS.

Royce
 

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Discussion Starter #15
I gave him a call today and asked him about the price, he said it was 200 for both sleeves. He also said it would be better to do that then to bore them all out, as there was not enought wear on any of the cylinders even on the ones that were over .010. He also seemed upset about me asking. he questioned if I trusted him and his shop or not, i told him yea, and that i was just double checking. It is a well known shop for my area. He did admit it was his fault he didnt catch it earlier. Shouldent he have earlier like 3 months ago when he did a hone job on it? This is my first time dealing with a machine shop.


For those who asked the engine is a 350, comp magnum 270 cam, flat top pistons, edlebrock performer RPM 70cc straight plug heads, edelbrock performer RPM intake, 670 street avenger. backed by a th 350 and 3.08 gears in a 66 el camino.
 

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I would get another block, and let him keep the one he did the work on without your permission. If he honed the cylinders previously he should have found the oversized cylinder. The fact that he did not indicates that he didn't even check cylinder clearance. Sleeving two cylinders is not the most cost effective way to solve the situation, boring the block to the next standard size is much more desirable, even if the the other six cylinder show no wear.

Find a new machine shop.

GM is not the only manufacturer that does this, I have personal experience with Ford products around the same time period.

Vince
 

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Sounds like he wasnt paying attention when he was honing the cylinders.
My what a coincidence that one revolution on the dial bore gauge is .010 :drunk:
And to top it off the pressed in sleeves are going to distort the cylinders next to them.


"Nope I sure dont trust you now buster. Mistake number one you missed the .010 over holes, mistake number two you started major work on my engine without telling me. Screw it Im not going to let you make mistake number three I want my stuff right now."

Just go back and tell him you thought it over and dont think hes the right man to be doing work on your stuff.
 

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I have to agree with Vince and Greg. I think I would be looking for a new machinist. I had a similar experience with my last engine, he was "telling" me what I wanted and not listening to what I was requesting. He was very pushy and got mad if you questioned anything. I left it there over night thought about it (couldn't sleep), so I went back and took all my stuff and found a new shop (my great machinsit from years ago passed away so this was a new venture for me).

Turns out the new shop I found is great, I explained what I was trying to do. How I would like it done. They had no problem and they did a great job.

Just because everyone goes to this guy you are dealing with doesn't mean he is right for you. He is probably great for people that just drop of engines and a wad of cash and say "I want this or that".

I don't understand his logic at all. In order to sleeve the two cylinders he had to bore them out in order to press the sleeve in. I have no idea why that was a better idea to him. Not sure what was discussed between you two but, I would probably tell him to keep the block and pick up the rest of my parts and find a new shop.

The most disturbing part of it is he didn't ask you if you wanted it sleeved or offer you any other options. Anyone in customer service knows that is a NO NO. A customer would rather hear bad news over, no news and make thier own decisions.

Royce
 

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I'd be on him about the exact reason why he sleeved that block. $200.00 US?! My machinist in Alberta, Canada charges $18.00 CAD/hole to bore an engine! I think that's around $100.00 USD on a V8, and if you're using cast pistons, the whole overbore would have cost like $160.00 USD! Without asking, to do that kind of an operation, sasys one thing to me - CROOK!!

To talk about the .010 overbore in those cylinders, it doesn't suprise me. I have torn down original engines, and found one main bearing journal .010 underzize, or a rod journal .010 under, while all the others were STD. And this on enginges that had never been cracked! I guess it comes from the "squeak" factor. I've heard it said that if it will save 1/4 of one cent, GM will stop the line, and make a change.....
 

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machine shop

Make it the last time you visit this guy.....

Try this, have a buddy call this guy and get a price to bore and hone a block .030 over. then compare it to the price he is charging you to do this shoddy work to your block and i think you will find right away he is blowing smoke up your dress.......

I don't know any one that can install 2 sleeves(the correct way) faster and more cost effective the a +.030 bore and hone....

Keith
 
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