VWDiesel.net The IDI, TDI, and mTDI source.

Engine Specific Info and Questions => IDI Engine => Topic started by: 85gti on December 05, 2008, 11:10:32 am

Title: Cracked block question
Post by: 85gti on December 05, 2008, 11:10:32 am
I am wondering if anyone evry fixed a hairline crack it a 1.6td or any engine for that matter.  I assume it would get me out of a bund if it doesn't leak and I am just wondering if anyone has any info before I go waste the next few hours learning to weld...  Thanks in advance.
Title: Cracked block question
Post by: zukgod1 on December 05, 2008, 11:14:47 am
It depends on where the crack is.

http://www.locknstitch.com/

This looks WAY cool..

Heres an example of the repair.

http://www.locknstitch.com/Repair%20pdf%20files/Cummins%205.9%20crack%20repair%20instructions.pdf
Title: Cracked block question
Post by: arb on December 05, 2008, 11:22:23 am
Yeah, do you have photos ? Cast iron is not where you want to learn to weld - it will become like glass and crack even more ;-)  I've welded blocks / manifolds. That's why you need an oven in your shop - you must pre-heat and slow cool to avoid the cracks.
http://www.vwdiesel.net/phpBB/viewtopic.php?t=15633&start=0
Title: Cracked block question
Post by: 85gti on December 05, 2008, 11:41:42 am
The crack unfortunatly is where the top front tranny mount is.  A bolt that was too long was used and caused a stress crack about an inch long.  I could go take a few pics but I figured you guys would know what I meant.  Thanks a lot guys!!
Title: Cracked block question
Post by: 85gti on December 05, 2008, 11:48:30 am
Quote from: "libbybapa"
Learning to weld is never a waste of time, but as others mentioned, leaning on a cast iron block is probably not a good place to start.  If the crack intersects a cylinder or a main bearing cap I'd toss the block without hesitation.  If it intersects a head bolt hole I'd toss the block with hesitation.  Anywhere else, I'd likely attempt a repair.

Andrew


It is cracked a few inches below the head where the tranny bolts to the block.  I think it is repairable but I really don't know how to weld that well.  Maybe I will take a picture to make this easier to understand.  Thanks again
Title: Cracked block question
Post by: arb on December 05, 2008, 11:49:55 am
That is probably the only important bolt I would think about welding - because it has several other backups and it is not under combustion pressure.

I recommend you take it to a speed shop and have their welder fix it, IF you don't know them, have him guarantee his work in writing that he will not damage it further.
Title: Cracked block question
Post by: smutts on December 09, 2008, 01:19:08 pm
Copper Sulphate solution and solder? :twisted:
Title: Cracked block question
Post by: jtanguay on December 09, 2008, 02:55:44 pm
you being in nova scotia, finding another 1.6TD shouldn't be a problem... i would only try to salvage this block if it was rebuilt not long ago... but thats just me!

that said... that locknstitch thing looks really cool.. i think you should do that instead of welding
Title: Cracked block question
Post by: arb on December 10, 2008, 06:51:54 am
Quote from: "smutts"
Copper Sulphate solution and solder? :twisted:


I doubt solder has the required strength, but it would be easy to try.
Title: Cracked block question
Post by: madrogers on December 10, 2008, 08:35:33 am
i fixed a 327 chevy engine in high school that had froze and cracked two ,2 inch cracks across the water jackets on each side of the block. I cleaned it and warmed it up v-ed it out a bit and used JB Weld , the repair lasted 5 years and sold the car like that with the fix still working .
Mark
Title: Cracked block question
Post by: arb on December 10, 2008, 08:46:34 am
Quote from: "madrogers"
i fixed a 327 chevy engine in high school that had froze and cracked two ,2 inch cracks across the water jackets on each side of the block. I cleaned it and warmed it up v-ed it out a bit and used JB Weld , the repair lasted 5 years and sold the car like that with the fix still working .
Mark


You're showing your age !!!  Man I miss the 283 I remaned.
Title: Cracked block question
Post by: 85gti on December 10, 2008, 11:29:13 am
Quote from: "madrogers"
i fixed a 327 chevy engine in high school that had froze and cracked two ,2 inch cracks across the water jackets on each side of the block. I cleaned it and warmed it up v-ed it out a bit and used JB Weld , the repair lasted 5 years and sold the car like that with the fix still working .
Mark


You're saying that the JB weld held the coolant pressure that was being produced?  If that is the case I may try that out and just see how it works!  Let me know
Title: Cracked block question
Post by: 85gti on December 10, 2008, 11:31:09 am
Quote from: "jtanguay"
you being in nova scotia, finding another 1.6TD shouldn't be a problem... i would only try to salvage this block if it was rebuilt not long ago... but thats just me!

that said... that locknstitch thing looks really cool.. i think you should do that instead of welding


The stitching is really cool and I would love to try it out but to be honest I have a nice 1,9TD coupe MK2 jetta and the engine swap isn't really worth the effort at the moment.  I will probably try the JB weld and see what happens.  Thanks for the responses though guys!
Title: Cracked block question
Post by: arb on December 10, 2008, 11:32:46 am
Quote from: "85gti"
Quote from: "madrogers"
i fixed a 327 chevy engine in high school that had froze and cracked two ,2 inch cracks across the water jackets on each side of the block. I cleaned it and warmed it up v-ed it out a bit and used JB Weld , the repair lasted 5 years and sold the car like that with the fix still working .
Mark


You're saying that the JB weld held the coolant pressure that was being produced?  If that is the case I may try that out and just see how it works!  Let me know


Coolant pressure is many orders of magnitude less than a bell housing bolt. He was talking about a crack that had to hold 14 psi - and the area of that crack could not have been even close to 1 square inch where your bolts is seeing thousands of psi. Unless I misunderstood the crack in the jacket as being a break.
Title: Cracked block question
Post by: madrogers on December 10, 2008, 11:17:54 pm
the jb weld held the coolant pressure the trick i belive was to be clean dry and a rough surface.
 the other comment i have is that i bought a mk1 pick up off a farmer that had only two bolts holding the trans in place to the engine ( the lower ones) and it had been like that for some time , i put them back in and no ill effecks from it so worst case you could leave that one out and try it unless you are going raceing.3 of 4 would work from my experiance.
Mark.
Title: Cracked block question
Post by: madrogers on December 11, 2008, 07:18:46 am
the JB Weld held the coolant pressure with no problem for 5 yaers, the trick was to have the surface very clean ,dry and rough.
 I bought a mk 1 caddy from a farmer and it had the top two trans to engine bolts missing and looked to be that way for a while (very dirty)so you could proubly get away with 3 bolts as long as yo are not going raceing.
Mark.





0