Sleeve thickness vs block integrity

Hopefully this is my last question on this engine.

pulled my A460 apart. and i took some sonic measurements of most the cylinders. as previous post mentioned, i had a 1.5" long crack through the siamessed wall of cylinder 5 and 6.
this block is bored to 4.625, max bore by most all definitions. there are other bores with small flaked off circles in patches.looks like shadowy pox marks. so at this point i will likely be looking at multiple sleeves.

So sleeves come in 1/16, 3/32, and 1/8" thick walls (normally). i have sleeved blocks in the past and always used 0.125.
however, since this will have sleeves side by side math comes into play.
4.9 bore center - .125 - 0.125 - 4.625 leaves 0.025 cast wall between them. this is basically nothing.
4.9 bore center - .09375 - 0.09375 - 4.625 leaves 0.0875. this is noticeably more material.

now the total thickness of cylinder plus the sleeve is the same since these will be dry sleeves.

***so the question is, is it better to have a thicker sleeve, or a little more cylinder wall to stabilize and lock the sleeve at the expense of the sleeve thickness?


As context, the cylinder walls were on average 0.240" material left, even at 4.625 bore. there were a few spots that dipped to 0.180 or 0.170". always in the center of the vertical wall where we would expect. So except for the one inch where the cylinders tangentially touch, there is a lot of meat to hold the sleeve. however, if i end up sleeving 3 consecutive cylinders, the middle bore would have this paper thin spot on both sides. And this looks to be the case on bores 5, 6, and 7. now if there was a 5/32 sleeve this would allow O.D.s to interlock whic could be of value.

i expect this engine to always live in the 700 hp range, so nothing earth shattering.


i found where frank Merkle did all eight bores with darton sleeves. i am not sure what thickness he used though.


Anyone have insight on sleeving side by side by side bores and what sleeve thickness you had success or failure with?

thank you all.

oh yeah, and any thoughts if this crack should be "stopped" from running around the cylinders. its a radial crack so it could continue to spread around the bore. of course it wouldnt meet at the other side so it could in theory just spiral around the bore.

basically should i somehow drill a 1/4" hole to capture the end of the crack all the way through, on both ends of the crack.

How would you even get inside the coolant area to drill the ends of the crack?....unless it just happens to be right in line with the core plug that you can remove and see it straight on.

Could be. You would have to use one of those funky angle adaptors on the drill.

drill method would be to take a carbide burr and grind into the wall where the crack ends. after there is enough of a ledge created, use a long 1/4" bit to drill into the rounded out spot. where the burr ground would hold the bit in place.

i look at it like this, these two bores are already open to the water cavity, but not as bad as if a piston blew threw the wall. but i do want to make certain the crack doe not propagate radially around the cylinder

supervel45 wrote:Frank claimed he used 4.8" on all 8.

A 4.7" at 4.625" bore =.075" on my calculator. .0375" is half of that. 4.8"-4.625=.175"/.0875". The 4.8" are longer also if that matters?

https://dartonsleeves.com/products/sleeves/manufactured-sleeves/ford-manufactured/

If you scroll over at the bottom of the link you can see the rest of the dimensions. Looks like 2 are for Aires blocks AR Ford.

Did you call Oakely?

his was a little different than my deal. he went to 4.605 bore.
the sleeves were 4.801 to he had .099" between bores. so (4.801-4.605)/2=0.98 sleeve wall thickness. so his finished sleeve was basically 3/32"
so at its weakest point he had 0.1" cylinder and 0.1" sleeve (roughly). this point would be at the front and back of the wall. the thrust and non thrust are not an issue

if i duplicate his effort it leaves me with 0.088" sleeve walls, and 0.099" cylinder walls. probably about the best compromise. makes sense why Merkle used them i guess

appreciate the sounding board.
ill visit the machinist tomorrow, but yeah, looks like Franks recipe is likely the way out of this.

Remember that the sleeve material is much better than the block material.

thank you Randy. that concurs with what some other well respected folks have told me as well. favor the sleeve material. also there is plenty of material near the decks and bottom to hold so i will be going with 1/8" sleeves.

for those that are interested in the failure mechanism.
i got a carbide burr out tonight and opened up the wall. i am fully grinding the crack out to stop propagation. then i am going to have it magnafluxed here locally to make sure i got it all.

in this process i opened some porosity. a handful of spots about the size of a a BB all with-in a half inch length.
so my guess here is that the crack formed from this and radiated from inside the wall outward. these three or four spots together just made a weak spot to crack from.

outside of these spots though, these block walls are absolute beast. basically grinding through 0.300 inch cast walls. these are jobs you save the new carbides burrs for.

funny thing, it looks like im grinding two stroke ports in a V8.

I can only speak to the crack drilling. Yes that is the correct way to repair a crack in cast iron. Drill a hole at each end of the crack and then weld it up with nickel rod. I guess you’re not worried about the welding part since it’s t will be sealed by the sleeve.

stanger68 wrote:I can only speak to the crack drilling. Yes that is the correct way to repair a crack in cast iron. Drill a hole at each end of the crack and then weld it up with nickel rod. I guess you’re not worried about the welding part since it’s t will be sealed by the sleeve.

since it was a ragged crack i ground the entire crack out with carbide burrs. tomorrow will get it mag-fluxed to look for any spiderwebs.

ive welded more than a few cast heads. in fact the D0Oe heads on the engine are welded from damage. so that is not a problem. one thing im certain of is use 99 percent nickle rods. machinest do not like the 55 percent stuff. it gets too hard.

ChrisH wrote:

stanger68 wrote:I can only speak to the crack drilling. Yes that is the correct way to repair a crack in cast iron. Drill a hole at each end of the crack and then weld it up with nickel rod. I guess you’re not worried about the welding part since it’s t will be sealed by the sleeve.

since it was a ragged crack i ground the entire crack out with carbide burrs. tomorrow will get it mag-fluxed to look for any spiderwebs.

ive welded more than a few cast heads. in fact the D0Oe heads on the engine are welded from damage. so that is not a problem. one thing im certain of is use 99 percent nickle rods. machinest do not like the 55 percent stuff. it gets too hard.

For crevices of that nature behind a sleeve, we simply use silver solder to fill it; (the sleeve will supply the strength needed).

You'll make more power giving up a little displacement and bore dia. and putting some cyl wall thickness back in the block. I've proven this several times with aluminum block customers who will listen.

Scott Foxwell wrote:You'll make more power giving up a little displacement and bore dia. and putting some cyl wall thickness back in the block. I've proven this several times with aluminum block customers who will listen.

i dont disagree. ring seal is everything. But the 4.625 pistons are essentially new. otherwise i would sleeve down to 4.560 without question or maybe even low 4.5xx.
new pistons adds alot of money to this repair that i would like to avoid. pistons, balance, and 8 sleeves is a fair amount to do while i am in the middle of sourcing parts for an A headed engine.
really wasnt planning on doing two at once here.

so for now its 4.625. this engine is destined for a 64 f350 after the A headed engine is complete. so plans are to keep it 600-700 and "reasonable" for street driving.

for now just finishing my part of the repair. i would have silver soldered it as Randy mentioned, but cutting the crack out with carbide burrs made for a hole 3/8" wide. and 1.5" long. so i started welding that in tonight.

not to mention silver solder is $100/lb right now, 99% nickel is $40/lb. the battery car people are killing prices on anything that conducts electricity.

ChrisH wrote:

Scott Foxwell wrote:You'll make more power giving up a little displacement and bore dia. and putting some cyl wall thickness back in the block. I've proven this several times with aluminum block customers who will listen.

i dont disagree. ring seal is everything. But the 4.625 pistons are essentially new. otherwise i would sleeve down to 4.560 without question or maybe even low 4.5xx.
new pistons adds alot of money to this repair that i would like to avoid. pistons, balance, and 8 sleeves is a fair amount to do while i am in the middle of sourcing parts for an A headed engine.
really wasnt planning on doing two at once here.

so for now its 4.625. this engine is destined for a 64 f350 after the A headed engine is complete. so plans are to keep it 600-700 and "reasonable" for street driving.

for now just finishing my part of the repair. i would have silver soldered it as Randy mentioned, but cutting the crack out with carbide burrs made for a hole 3/8" wide. and 1.5" long. so i started welding that in tonight.

not to mention silver solder is $100/lb right now, 99% nickel is $40/lb. the battery car people are killing prices on anything that conducts electricity.

I thought that might be the case with the pistons. I'd say you're on the right track. The .125 wall should be plenty for what you're doing as long as whoever is installing the sleeves knows what they're doing.
I probably don't have to say this but just make sure you leave enough of the ID to finish...they won't be very round when installed.
Are you using the cast iron tig rod by any chance? I've heard that it's really expensive but almost like magic for welding iron.

[/quote]
Are you using the cast iron tig rod by any chance? I've heard that it's really expensive but almost like magic for welding iron.[/quote]

no, i heard good things about some of that magic rod. im just using NI99.
i know how to deal with it and it machines well so i just stick with it. i would have brazed it but the hole was too big after i ground everything out. so nickle it is.

some day i will have to try some of the tig cast rod. i think part of the deal is i welded for so long with only an AC stick box on everything i became pretty good with it. now that i have a DC stick welder its its just seems so easy i still using it alot.

i did try tigging with old NI99 once. knocked the flux off. resounding failure. i kept getting too much heat in the cast and cracking.


dfree
Kid not, i look the block over everytime i do something with it, checking for other cracks, just trying to make certain

My nephew is a welder by trade and I have seen him work miracles Tig welding with flux rod. I tried it t on a cast water pump with a cast 55 rod and did manage to seal the crack but it wasn’t nearly as pretty as his work.