IL6 block crack at head bolt hole

[ziggy]

hi folks, long story short. and i think i know the answer(a different block), just don't want to hear it. <br />just went out to start cleanin up the block on my il6 chevy 250, 1972... heads off bein repaired. looks like i'm doing things backwards as i just descovered i got a crack on the block. port side, front screwhole. right by the waterpump. think it'd be the #13 bolt. no water leaks externally or internally that i'm awhere of... oil is clean.<br />so did i freeze damage it? where does freeze damage show up at usually on a il6. not like it makes any difference. i winterized dry. drained block, manifold and riser and removed waterpump hose at bottom. so felt i had a pretty dry block. anyways...live and learn i guess..<br />the crack is visable right down the screwthreads. 2 cracks, 45* apart, cracks leadin to front and port side. i can't think very seriously that i'd ever get a bolt to torque up to 90 ft lbs without breakin the corner of the block off or just pullin the screwthreads right out of it...<br /><br />any advise? am i hopeless? i guess money can repair anything, but i aint got a lot... i can't even think that a good Machinist could be ontoit(gonna ask one though) as the crack is inside the screw hole leading outward. surface of block(deck) shows the crack too. the surface of the block on the outside, ft and port side show no eveidence of a crack. well, right at the very top front of the block, 1/32 showin on the front, maybe.. crack is all the way down the screwthreads, visiable... what me next best step.....

 

[Bondo]

Re: IL6 block crack at head bolt hole

Freeze Cracks on that motor Usually are along the Port-side,.. Just above or below the Coreplugs.....<br /><br />Are you saying it's a Headbolt Hole that's Cracked,..???...

 

[ziggy]

Re: IL6 block crack at head bolt hole

Bondo<br /><br />Are you saying it's a Headbolt Hole that's Cracked,..???...

yep, that's exactly what i'm saying

 

[ziggy]

Re: IL6 block crack at head bolt hole

interesting, not to much feedback on this subject. kinda leavein me to my own demise i guess. <br />only ideas i came up with over the weekend, not even knowing what it is i'm thikin about. found this article, about crack repair. i have no idea if it's cost effective let alone viable.<br /><br /> http://www.aa1car.com/library/ar497c.htm <br /><br />other idea that the neighbor came up with is, just use yer sealer ontoit and put it back together again. ya will either win or lose. maybe not torque up the 13th head bolt to it's full torque value. i don't know...anyone with any bettter ideas. i feel i'm already lookin at a different block unless something like a pin would work...i'm still open to suggestions......?

 

[Bt Doctur]

Re: IL6 block crack at head bolt hole

drill it clean, install a oversized slug, weld it in, drill and retap to original size.had one that took out the threads there, retapped for an oversize bolt,(had to be 2in. longer cause the bolt head was too big to fit in the recess on the head),machined a spacer with a cutout for the valve cover. looked strange with a head bolt sticking up that far but it worked.

 

[ziggy]

Re: IL6 block crack at head bolt hole

thanks bt doctur. i appriciate any suggestions. i feel reel bad about the way i didn't check the deck prior to doin the head. anyways. now i'm somewhat commited to a short block i'd think. if i was to go that route. not that i'm sayin i am. i'd realy rather repair than R&R if i could. i got no ring wear. at least not with the fingernail feel. another reason is i have read far to many articals about remanufactured engines not bein up to spec. i hate to admit it, almost. but i am tech school trained in automitive, and we were trianed to plistigage shortblocks. 1 in 4 wouldn't pass the test for rod brgs. or crank brgs.....that's not insperational for a remanufatured IL6. do ya think a remanufature goes to the trouble of replastigagein crand brgs or rod brgs......<br /><br />bt doc, that sounds like a reasonable repair. my concern would be the fact that cast iron expands and contracts at different rates than perhaps the weld....good that you've had success that way,, food for thought for me, and that's what i need, thanks....

 

[thunderroad]

Re: IL6 block crack at head bolt hole

I agree with your neighbor, especially considering the location of the cracked hole...and the age of the engine. I've got a 69 IL6 and that's exactly what I'd try first in the same situation.

 

[Bondo]

Re: IL6 block crack at head bolt hole

Sorry Ziggy,..... I read your link last night,+ never made it back to post........<br /><br />The Pinning is an Old system, that just Won't Work for You,..... It's for Cracks that are Inside,... Not Outside......<br /><br />The Spray Welding is Interesting,..... I've Brazed,+ Welded alot of Cast Iron,.....Never got My hands on a Spray Torch.....<br /><br />I'd Probably Try, grinding,+ welding,... But Blocks are Tough,... Lots of Iron to Heat.....And Your's is Assembled.......<br /><br />It would Probably make More Sense to Try the Epoxy route,...... <br />Less Trauma to the Block,+ The Actual Chances of it Working are about the Same.............. <br /><br />Lock-Tite has a Whole Bunch of Different Chemicals for Just This Reason........<br />I haven't looked in awhile,... But Googling Lock-Tite just Might bring a little Light to your Delema............<br />I remember using some of that Stuff,.... That by using the release agent,... <br />It was Claimed that the Bolt could Still be Used,+ Retorqued,......<br />Don't Know Really,...... It Held the Air-Shift Valve from being Blown Off the side of My Road-ranger Transmission.......

 

[ziggy]

Re: IL6 block crack at head bolt hole

thanks folks for the help. the loctite idea sounds good, i need to do some googlein. i talked to my machinist guy today. i ask him about them pins. he said he was an expert on that subject and knew when and when he couldn't use them... this is just some cat i picked out of the phone book ya understand. so far though i think i believe him. he says bring it on by and we'll have a look at'er. gonna do that round abouts thursday i think. i kinda like a fella that has a lot a pride in what he does. time will tell if i think that in the end. i will talk to this fella about the loctite ideas to bondo....oh, thats three yeahs for just puttin it back together again...????<br /><br />

Bondo<br /><br />The Pinning is an Old system, that just Won't Work for You,..... It's for Cracks that are Inside,... Not Outside......

either i don't understand or i was lame in my description of the crack. to me it is from the inside leading out. the front port headbolt hole screwthreads has a vertical crack from top to bottom of the screw threads themselves. there are 2 cracks. one is from the front of the screwhole leading to fore. one is port side leading out. crack is not visable to me anyways on the outside of the block. the deck does show the cracks leading in the stated directions. i assume the crack to be as deep into the block as the vertical length of the crack that is visable in lookin at the screwthreads, just an assumtion though. i suppose a magnaflux would really tell ya...$$$$.. .....see i'm still smilein.......

 

[ziggy]

Re: IL6 block crack at head bolt hole

well, took the boat to the welder machinist guy. says he has good new and bad news. <br />good news is it's fixable<br />bad news is the engine has to come out + be disassembled to be welded. . he was nice and said i could leave the cam bearings in it if i wanted. what a nice guy.<br /><br />well, i've been thinkin now. man, this is the worst case scenerio for me. being a poor boater and all. i do not want to get rid of the boat. i like the boat, i like a trihull, i like the engine. i can not, in my mind do me a half way job of repairin it. (gotta at least try to do it right)if i glue the crack, i will always wonder when it will break off, cause me a head gasket leak, whatever. it aint right. so i guess at this point i'm gonna go for it. (under the shade tree as i gots no where else to do it)the head aint been started being repaired yet as i caught the wleder machinst guy prior to him being to far along with it. so i have my options open right now. remanufatured engine, or fix what i got. i think it's time for another post with a new topic. thanks for the replys to this one. ya all have been most helpfull.....looks like i got a ways to go before i will be boatin this year, if at all. .

 

[RubberFrog]

Re: IL6 block crack at head bolt hole

I wouldn't weld it. If you're gonna go to the trouble of rebuilding it, I would just get another block and start from there. You'll always wonder if the weld will hold up.

 

[lilmandavis]

Re: IL6 block crack at head bolt hole

could always check on the price of a long block. thats the way to go these days man. the bottom is probably blown out of that hole to. id say that carcked when torqued down. to much oil on the threads? cleaner solvent in there maybe? water might have been in there as well and froze. get a long block and get it over with. by the time you spend at least 250 on just that bolt.... another 100 on the head. 150 for engine boring and grinding your half way to a long block almost. rebuild kits arent that cheap either.

 

[ziggy]

Re: IL6 block crack at head bolt hole

RubberFrog<br />Member # 55622 - posted May 12, 2006 07:39 PM I wouldn't weld it. If you're gonna go to the trouble of rebuilding it, I would just get another block and start from there. You'll always wonder if the weld will hold up.

i guess i would think a weld would be better than glue. new would be best. i'm wondering though in this day and age if a block truely can't be welded and have it work as well as new. ya always have to turn in your core when ya get a new one. i'm guessin someone welds up the problems and the remachine it and rebuild it. as for me rebuilding. that wasn't what i was gonna do. though that notion brings a question to me. if i weld, i wonder if the deck don't need planed? i would think so. the welder i been seenin seems to be pretty sharp. i don't know one welder from another, but this fella garenttes his work. showed me a manifold with a crack in it. 2 acutually. one he'd repaired, it didn't break there, it broke somewhere else, not at his repair. anyways. as for rebuilding. i was just thinkin perhaps i'd hone the cyl. maybe some new rings. reuse everything else assummin i don't have any issues. don't know if i can get away with that. but i'm on the cheap within reason. still needs to meet specs or i'll have to spend more bread. <br /><br />

lilmandavis<br />Member # 71023 - posted May 12, 2006 08:01 PM could always check on the price of a long block. thats the way to go these days man. the bottom is probably blown out of that hole to. id say that carcked when torqued down. to much oil on the threads? cleaner solvent in there maybe? water might have been in there as well and froze. get a long block and get it over with. by the time you spend at least 250 on just that bolt.... another 100 on the head. 150 for engine boring and grinding your half way to a long block almost. rebuild kits arent that cheap either.<br />

checked a jasper engine out. 2400 round abouts. complete with carb. fair price but not quite what i had in mind. hopefully. may end up there, but not w/o seen what i got to work with first. interesting speculations on possible causes for my failure. one thing can be eliminated though. bottom is blowen out the bottom of the holes. all of em as they ain't blind holes. they are exposed to the waterjacket. that's how i found the crack. i didn't know if they if headbolt holes were blind or thru to the waterjacket. by readin a couple of other posts, i suspected they were thru to the waterjacket. that's why the thread sealer on at least my headbolts. also i've price the headjob. round about $300 for the head. new hardened seats, head is good apperently, no cracks anyways. weld bock est was $180. so i'm thinkin that pluse some gaskets is my cheap way out. i don't know. reckon i will find other issues on the way....like a leaky rev. lock valve. if all works well, i will need to repair that while engine is out. so i can break the bolts off and have a hope of repair. har har..problaby not though from what i've expereiced on workin on a boat anyways.... ah, boatin sure is fun, sigh.... guess i'd best get to work. made a drive stand last night. (from folks posts here on iboats) wonder how it'll slide in the dirt and grass which is my work environment..... ah, one obsitcal after another..

 

[waterdog85170]

Re: IL6 block crack at head bolt hole

i had the same problem on my 140. i drilled the hole and JB welded a heli coil in for strength and cleaned and JB welded the crack. i have about 20 hours on the fix and its still holding! one of my buddies suggested the idea and i was skeptical at first but im very happy it worked. good luck!

 

[waterdog85170]

Re: IL6 block crack at head bolt hole

forgot to add that i used a fine flat file to smooth the deck at the crack as one side of the crack seemed to feel higher than the other.

 

[lilmandavis]

Re: IL6 block crack at head bolt hole

2400 $?????? got a 5.7 liter long block for 1500 and thats expensive cause it was a vortec. you dont need a drop in motor. just a long block. unless your manifold everything else that goes on is bad as well! id search around a little.i found a v6 for a 1000 so im sure that an inline isnt much more if any!!