The Stovebolt Site Forums The Shop Area Engine Shop Need to sleeve a 235

Completely rebuilt my '61 235 and after 1500 miles a hole developed in number 4 cylinder and started sucking coolant into the cylinder. My builder bored it .060 over and I guess since it was from a beach area and had sat for quite awhile it suffered rusting in the water jacket. Anyway, am thinking of sleeving it in order to save all the new parts already invested in. Can I bore the sleeves back to .060 to reuse the new pistons or should I buy smaller pistons? Does it make sense to sleeve all the cylinders? My builder said he would work with me on the price, but I wanted to have an idea of what a reasonable cost would be before I talk to him and whether I should expect him to tear it down and put It back together at little or no cost. Looking for advice since I paid 4500 already for this rebuild!

Perfectly safe to sleeve just the bad one, and run a standard piston.

Panic, I'm confused...a standard piston? Is that the one that's already in place or a unbored out stock piston?

There two basic sizes of sleeves- - - -3/32" wall thickness and 1/8" wall. Since you're probably dealing with more than one thin spot, I'd recommend going with the 1/8 wall sleeve, then boring the sleeve .060" and reusing the piston you have now. Taking 60 thoudsndths out of a 3/32" wall sleeve doesn't give you much remaining thickness to work with.
Jerry

Thanks Jerry, this is what I need to know. Where Panic said I could get away with just doing the one cylinder, it seems to me the wise move would be to do them all rather than have this problem reoccur in another cylinder. Still don't know what the cost breakdown might be...

Unless you've got a reason to keep that block with that truck, such as a matching-numbers show winner, sleeving all the cylinders will be prohibitively expensive. I don't know what the labor rate is now, but back when I was doing a lot of machine work, my charge was $100.00 labor per hole, plus the cost of the sleeve. It takes 3 or 4 passes with the boring bar, minimum, just to hog out enough metal to install a sleeve. At 15 minutes per pass, that's an hour for each cylinder, install the sleeve, face it off, and then bore the sleeve to fit the piston, and hone out the final .002" or so to get rid of the machining marks. Multiply that times six, and the dollars add up in a hurry! If the rust in the water jacket is bad enough to need sleeves in all six, you've got a boat anchor! Why didn't your machinist figure that out early on?
Jerry

I sure spent a lot on rebuilding that block, not too excited about spending much more. I see the builder on Tues.

The point that Panic is making is simply the cheapest and safe way to correct the problem at hand. One unmatched piston won't hurt any thing. And spending a lot more money on this engine won't get you any more reliable. Fix the one hole with a sleeve. Drive it while you look for another engine. Good looking truck by the way.

Have the one hole sleeved and then bored to use your new .060 piston.

Your machinist should be able to check that block before doing any more work to make sure it's okay in the other cylinders.

Unless the previous owner had been putting sea water in it I doubt that simply sitting by the sea had much to do with the inside of the water jackets rusting. My bet is it was a thin spot in that cylinder to start with and when it was bored it opened the hole up. Or the cylinder was pitted bad from the piston side (as I recently had one) and the hole opened up.

Have the sleeve installed, bore it to match your pistons and put it together.

It's not uncommon to find a "sand hole" in a cylinder casting that will open up when a large oversize piston is used. A bit of contamination during the casting procedure might go unnoticed for years until it's exposed during a rebore job.

We used to have problems with 350 Chevy race blocks with "core shift" problems. Standard-bore blocks would perform well, but when we bored them .030" over to make 355 NASCAR engines and then beaned 'em up to 600+ HP, it was possible to get a crack in a cylinder wall.
Jerry

Thanks for all the info guys. I now know more about how this is going to go. Nice to know I don't have to sleeve them all! This forum is invaluable to guys like me!

One trick we used on the race blocks to look for potential leaks was to block off all the cooling passages and pressurize the block and heads with a garden hose. There's something about 40-50 PSI water pressure that will make even the tiniest pinhole leak show up!
Jerry

After you get the sleeve installed and bored and honed, make sure the machine shop hones the adjoining cylinders because installing the sleeve will distort them. But i'm sure they know this.

If it rotted thru one cylinder I would be very suspect of the rest of it and as Jerry pointed out doing all is cost prohibitive. Place a local classified ad for a 235 and you may be surprised how many rodders have one of these "boat anchors" laying in the corner of the garage they wish would disappear. If you want to try with what you have get it sonic tested.

My quote to sleeve 2 cylinders and line bore the other 4, includes clean/flux, new cam bearings etc etc (basically give them a block with 2 cylinders to sleeve, and 4 to bore, install cam bearings and get back a motor ready to put back together)
was $800.

Compared to just having all 6 cylinders bored/honed to .020 = $180

These were for separate motors... the one with the bad cylinders was scrapped.

Well, guess what? Couldn't find a hole in the cylinder so we had the head magnafluxed. It showed three cracks and a pinhole! I'm assuming my problem can be solved with a good head and I've been looking for one with no luck yet. Like a fool, I sold all of my old engine stuff after I got the rebuilt engine back thinking my problems were over. Now I need another 848 head. A friend offered me his '56 261 motor but that would be another rebuild. Anyone have a good head for sale?

Put an ad in the parts wanted section. You should be able to find one.

A good machine shop could fix the head you have.

I have a 848 head ready to go on but it has a stud with no threads in the bolt hole at each end of the manifold side. The old head had bolts there. Should I try to remove them with vise grips?

You might have to heat the studs up, then put a vice grip on and they will turn out. The holes are threaded.

[IMG]http://imagizer.imageshack.us/v2/150x100q90/843/cxze.jpg[/IMG]]Imageshack.com[/url]

My 1954 Head uses the dowel studs.
You can use the dowel studs on your head.
You don't need a bolt in the manifold ends.
Use a bolt if you like.
Some think using a bolt in the manifold
ends can lead to manifold cracks.
I'd use the end dowel studs just as
GM built & designed it.

If you need new nos dowel studs
like these below @photobucket

http://i669.photobucket.com/albums/...pecs/Manifold_End_Studs__zps89cd0854.jpg

They are available
GM NOS @:

Whisler Chevrolet
Rock Springs, WY
phone:307-362-5677
They have ( 10 ) GM # 3835487

Banks Chevrolet
Concord, N.H.
phone:603-224-4055
They have ( 4 ) GM # 3835487

Dan's Obsolete
Chinook, MON.
phone:406-357-2615
They have ( 8 ) GM # 3835487

GP

Re: pressure test.
40-50 psi water is a useful test for vacuum or water leaks.
Not as useful to show a perforation between the jacket and the interior of the cylinder bore - because that's more like 700 psi.

Thanks Guys, since the studs are part of the design I'll go ahead and use them. I was told the cylinder head bolt torquing sequence was important, and it's not in my book. Any one know the sequence?

235 Chevy Cylinder Head torque sequence.

@ photobucket

http://i669.photobucket.com/albums/...ead_Bolt_Torque_Pattern__zps8aadaa39.jpg

GP

Thanks GP, that's just what I needed. Hoping the new head solves my problems!

Good news! Head is on and purring like a kitten! The vibration I was experiencing turned out to be those bad cylinders getting the water in them. No more vibration. My cheapo chrome valve cover won't seal for crap so today it's back to the boneyard to find the stock one. No big loss. Celebrating my return to being a daily driver! Thanks for all the help folks.

The old ones can be a pain as well. You need to be a bit of a tin smith to get even them to seal. I place the cover on the head without the gasket and check to see if the sides are bowed out (they all seem to be bowed out somewhat), then check to see if the seal area of the cover is tight where it meets the head and adjust with a hammer and appropriate sized punch to massage the cover for a tight fit.
Carl

Good news, enjoy!