Advice on stroker build with cracked cylinder

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RAMM said:
^^^^^^^^^^This is correct. Done PROPERLY the sleeved cylinder will probably have the most integrity of all the cylinders. Sleeving is a simple process but requires precision and a machinist that can hit their marks dead on. For example you just don't bore a hole and slam a sleeve in. You determine with a sonic check if the major and minor thrusts will favour a slight offset. Then you setup the cylinder and bore the hole (leaving a step at the bottom) while also leaving .002"-.003" interference-based on measuring the sleeve first. The boring tip will leave a chamfer at the step so before breaking setup I have to change tips to a counterbore style that will square up that chamfer at the step. Then I measure the length of the cylinder (usually 6") and install the sleeve in the lathe and part off the excess from the non-chamfered side of the sleeve leaving me about .125" that will protrude from the deck after install. Then the sleeve gets cleaned and tossed in the freezer for a few hours or overnight. Then the cylinder gets thoroughly cleaned and dried. When the time is right, I get my sleeve driver (which is a 2" thick disc of aluminum with a 1" bolt through it), BFH (2lb sledge), PPE (gloves, glasses, ear defenders) sitting on the deck of the block. Then I smear Permatex green sleeve retainer stuff all over the crack. Then I don all my PPE, walk to the freezer (about 40' away) run back to the boring mill and beat the sleeve until I feel it bottom. With any luck at this point the sleeve will protrude about .100-.125" and I proceed with the same counterbore cutter to machine the excess off as close to the deck as I dare. If the block is not getting decked then I finish with a nice sharp large file. The sleeve is then bored to within .005" of final size and the block then moves to the CK-10 for honing. When all is said and done if I did the job right you cannot tell where the sleeve is. I am sure I am forgetting some of the steps but it is simple but not easy to execute at least based on some of the sleeve jobs I have seen. I charge by the hour and the last sleeve I did two weeks ago (BBC 468 lots of nitrous) cost $600+ sleeve. If you are worried about the job have the shop pressure test it afterwards--I only do that if I have any doubt if I "got" all of the crack.

Sorry for the wall of text--to make a long story longer--have it sleeved it will be fine. J.Rob
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Very concise, thank you. I'm confident enough that a properly done sleeve will handle the heat and pressure of the combustion. Would the crack in the block, behind the sleeve be a weak point for other stresses/forces the block is subjected to? The machinist mentioned twisting.
 
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Th
Rocket said:
You can always sonic check the block. If there is enough minimal wall thickness to build at that oversize you are all set of that is your preference. If there is not enough then you can pursue the sleeve. A good shop should give you an honest opinion on your block given the crack and your intended plans? What are they telling you is the best course of action given the blocks current condition? Sounds like they build high horsepower engines. They are likely to have seen cracks before.
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They feel that the crack will create an issue weakening the block's strength, rigidity, etc. and may allow movement resulting in more drama. They are confident the sleeve will cure the cylinder issue though.
 
nm9stheham said:
'Stop drill' the ends of the crack. Once stopped, I can't see how it can effect anything else. And if you bore for a sleeve, the remaining wall integrity is not anything you can count on anyway. Take a bore that has a walled thinned to .150" or less due to core shift, bore for a .093" sleeve, and you have <.060" wall remaining. Not much strength left there anyway. So the crack issue goes away IMHO, as long as you stop it form extending into the upper and lower ends of the bore. The orientation of the crack is good in that regard, since it leaves the vertical strength of the other parts of the bore intact.
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That's sounds like a good approach, especially if they can stop drill the crack. How about the water around the crack? Even though it won't be an issue in the cylinder anymore, wont stop drilling both ends of the crack create 2 more places for water to escape the jacket and seep into the void behind the sleeve? Would that be a potential future problem or...?
 
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No worse than the rest of the cooling system I would say.
 
lots of good suggestions- drilling and pinning the ends of the crack for example and using premium sleeves- like always
did anyone mention a short fill?
report on sonic check if available in your area or at least look for visible core shift (cam tunnel centered etc)
get the water passages clean/ de rusted
should be good
if bad just use a 360 nothing special about most 340's although there were some trans am and 6 pack and others
 
I'd rather sleeve it than toss it if it were me.
Then 1/4 fill it.

I've gone .060 on a 1971 340 block with no issue.
 
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moparodbuster said:
That's sounds like a good approach, especially if they can stop drill the crack. How about the water around the crack? Even though it won't be an issue in the cylinder anymore, wont stop drilling both ends of the crack create 2 more places for water to escape the jacket and seep into the void behind the sleeve? Would that be a potential future problem or...?
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Yes, that makes all the sense in the world. But again, the 'green sleeve retainer stuff' will help.. and you can put other material in the holes. The bored cylinder IS going to expand at that crack when the sleeve goes in. I'd rather do all I can to make the stress at the ends of the crack stop rather than possibly working its way on up or down to the top or bottom. If that happens, then it would be ruined.

As for twist and other stresses, yes, each cylinder wall is part of the block's rigidity. But, they also may be wanting to just cover the whole situation with you. How much it can/may effect strength is not knowable unless someone had done the exact repair.

I'd reason that:
  • the outer and inner surfaces of the block are still intact, still providing support
  • once the cylinder is bored and the original wall thinned way down, then the cylinder's strength is drastically reduced anyway, with otr without cracks. (And really.... who actually knows how may thinned walls crack after the sleeves are installed?) Since this has been done successfully and survived at your proposed power levels, that indicates to me that it is a fairly good bet to survive.
In your shoes, with the difficulty of sourcing blocks, I'd go for it. But I realize that this is a judgement call. Maybe first cost out getting another block. Sleeving is certainly not free.
 
Last fall we broke the head off a exhaust valve and put 3 cracks in no 8 cylinder.....got it sleeve for 139 dollars....reassemble the engine....it is a .040 360 with a 4 inch crank.....engine has run 10.43 in Vegas air so far....a
 
70aarcuda said:
Last fall we broke the head off a exhaust valve and put 3 cracks in no 8 cylinder.....got it sleeve for 139 dollars....reassemble the engine....it is a .040 360 with a 4 inch crank.....engine has run 10.43 in Vegas air so far....a
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Impressive to say the least. J.Rob
 
moparodbuster said:
Th

They feel that the crack will create an issue weakening the block's strength, rigidity, etc. and may allow movement resulting in more drama. They are confident the sleeve will cure the cylinder issue though.
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That crack doesn't mean jack crap. You are overthinking this and mentally masturbating yourself into a corner.

I can't count the blocks I've sleeved. I've sleeved them with holes in the cylinder walls.

Use a .125 wall sleeve, sleeve it and move on.
 
yellow rose said:
That crack doesn't mean jack crap. You are overthinking this and mentally masturbating yourself into a corner.

I can't count the blocks I've sleeved. I've sleeved them with holes in the cylinder walls.

Use a .125 wall sleeve, sleeve it and move on.
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Yeah some folks just like to drive themselves insane. You can what if yourself into a coma. Why?
 
RustyRatRod said:
Yeah some folks just like to drive themselves insane. You can what if yourself into a coma. Why?
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Easy to say if you can afford to pay for mistakes! I'm not as financially well off as most people playing with these toys. Ive had to save for years to do this so I damn well want to be sure I make the right decision. But thanks for your 2 cents anyway champ!
 
I've had a cracked cylinder in a 440. After a new sleeve was put in, as a test we lightly skim-bored the new cylinder surface with a (same KeyWay) cylinder bore.
After that it became obvious the bore hadn't touched the area where the original crack was. The sleeve had conformed itself slightly to the old cylinder shape. (I have pics of this somewhere but need to put them on my site)

Given that experience, and you're saying you will race the engine anyway, I would say do a 'partial or half fill' with concrete in the block to limit any further distortions and have an ease of mind.
 
yellow rose said:
That crack doesn't mean jack crap. You are overthinking this and mentally masturbating yourself into a corner.

I can't count the blocks I've sleeved. I've sleeved them with holes in the cylinder walls.

Use a .125 wall sleeve, sleeve it and move on.
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
^this !!^

we sleeved a hemi superstock type block, no. "5 and 7 cyl's," , back in the 70`s, raced it for 14 yrs. It`s in a street car car now and running .
 
moparodbuster said:
Easy to say if you can afford to pay for mistakes! I'm not as financially well off as most people playing with these toys. Ive had to save for years to do this so I damn well want to be sure I make the right decision. But thanks for your 2 cents anyway champ!
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Ha! Me and you both. I just finished a 396 Chevy short block. From block #2. Block #1 was cracked in a cylinder. Had it not been cracked in TWO more places by a freeze plug, I would have sleeved it. It was cracked in a cylinder almost identical to yours. I would have sleeved it and never thought about it again! You're losin too much sleep over this, trust me. Just sleeve it and you will be fine. It will be a nice motor.
 
BigBlockMopar said:
I've had a cracked cylinder in a 440. After a new sleeve was put in, as a test we lightly skim-bored the new cylinder surface with a (same KeyWay) cylinder bore.
After that it became obvious the bore hadn't touched the area where the original crack was. The sleeve had conformed itself slightly to the old cylinder shape. (I have pics of this somewhere but need to put them on my site)

Given that experience, and you're saying you will race the engine anyway, I would say do a 'partial or half fill' with concrete in the block to limit any further distortions and have an ease of mind.
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Then you didn't use a .125 wall sleeve.

One thing I always do is look at all the sleeves available. I didn't just order the sleeve that the book called for.

I can't remember the part number that was called out for a 340 (I used to but I'm older now and that's what they make charts and catalogues for) but, if I was doing a sleeve for your engine and you were going to go .040 over, (so a finished bore size of 4.080-4.081ish depending on what you need for piston to wall clearance) I'd look at the chart of available sleeve sizes and look for a sleeve the correct length (or longer as it's easy to top cut the sleeve and if it's way too long put it in the lathe and part it off first...it ain't that hard) and with a bore size of 4.100ish.

But you say...I'm only going to be 4.08ish finished. Yup you are. But the sleeves are .030-0.035 UNDER nominal bore size.

That means, once the sleeve is pressed in (you only need .001-.0015 press on a sleeve that diameter and if you leave a .100 wide ledge at the bottom for the sleeve to seat on it will never ever move) you will have a bore diameter of roughly 4.068-4.070ish and that's PLENTY of material to hone out. You don't even have to bore it.

When you are done, your sleeve will have about a .125 wall or a bit more and the damn thing is made of better material than the block.

Some of the fastest guys in the country were sleeving all 8 holes back in the day before you could get harder aftermarket blocks, especially they Chevy guys because the stock Chevy block is soft as butter compared to the Chrysler.

That is the brief rundown of how to correctly select a sleeve. It ain't that hard.

Put a sleeve in that hoopty and get on with it. I've sleeved blocks that have been blown alcohol, stuff that's been in the low 7's naturally aspirated and everything in between.

Think about it...every single aluminum block out there has 8 sleeves in it.
 
I built a 440 ci out of a 400 block (4.185" x 4") in 2014 EMC using 8 Melling HP sleeves with the flange (step) at the top. That engine had something like .280"-.300" wall thickness-LOL it made a lot of power very very easily. Then in 2016 I wanted to compete in the 2016 EMC in the big block SPEC class (470 ci). Made a sleeve puller -pulled all 8 sleeves out of the same block-bored and installed 8 sleeves for a 4.32" bore--Made a lot of power (696 hp) finished 3rd and is running in some kids '69 Satellite that he says is "crazy". So that is 16 sleeves in the same block. Sleeve it and forget it. J.Rob

This Chrysler Big-Block Has A Twist - Windows In The Block!
 
I don't think I have ever seen a more thoroughly answered question on FABO, with opinions, reasoning, parts, process descriptions, and supporting success stories from very experienced people. It is a 500 HP iron block application, not a 1000HP AL block application.... different animals altogether.
 
nm9stheham said:
I don't think I have ever seen a more thoroughly answered question on FABO, with opinions, reasoning, parts, process descriptions, and supporting success stories from very experienced people. It is a 500 HP iron block application, not a 1000HP AL block application.... different animals altogether.
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Agreed.
Lots of good discussion here for sure. Bottom line, it sounds like the OP is nervous about running a sleeve. Then don't do it. Find another block and start again. With all the positive sleeve opinions, I wouldn't have a second thought about doing it that way.
 
YR's walk through on sleeve section should have been valuable to OP
sometimes you have done it so many times that it becomes second nature or standard operating procedure and I sat up wide awake
LA Sleeve is still nearby and was right around the corner from an older location in Santa Fe Springs- great people
 
Wrist pin got loose and troweled a slot in cyl. Sleeve it, as good as new.
100_1853.JPG
 
RustyRatRod said:
Ha! Me and you both. I just finished a 396 Chevy short block. From block #2. Block #1 was cracked in a cylinder. Had it not been cracked in TWO more places by a freeze plug, I would have sleeved it. It was cracked in a cylinder almost identical to yours. I would have sleeved it and never thought about it again! You're losin too much sleep over this, trust me. Just sleeve it and you will be fine. It will be a nice motor.
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rrr, did u investigate block pinning the cracks "by" the freezeplug holes ?
 
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