repairing Passat B4 crack in block

ken.fresno-tdi

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95 Eurovan EVC camper with 98 AHU engine (VeganVan02); 01 Jetta ALH engine and parts - waiting for transplant into 97 Eurovan (VeganVan03);05 BEW Beetle
Well, I've got a real problem. I bought a 97 Passat TDI with only 58,000 miles sight unseen from an auto auction a few months ago. I soon found the 5 speed transmission to have serious problems, so I found a new (used) one to replace it. I thought I was in the clear. When I was replacing the tranny, I got way under the car and found 'The Crack.' There is a crack in the block where the engine and tranny meet on the very bottom of the engine. The previous owner tried to 'fix' it with some JB weld. Perhaps it held up for a while, but I am not planning to continue with that 'fix'. So I am now in a quandry. I have a good car with otherwise very low miles, but with a bad block. I really don't have 2 or 3k for a new block, plus the rebuild time. I am wondering about the option of welding the crack. I know it is not ideal, but I am wondering if it is even an option. If I remove the pan, is it possible to weld something like this? The block is intact - i.e., the crack does not leak oil or water. The crack is on the corner of the flange where the bolt that connects the engine to the transmission is located. I posted a picture at:
http://pg.photos.yahoo.com/ph/ken_fran/album?.dir=/1c22scd&.src=ph&.tok=ph4BsLFBF0MzNtoY

What to do? Can anyone lift my spirits, or am I destined to have a failed B4 in my garage for months to come? :(
Ken
 

tditom

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formerly: 2001 Golf GL, '97 Passat (RIP) '98 NB, '05 B5 sedan
It appears to be a crack on the outside and doesn't go into the crankcase. Why can't this be properly welded?
 

ken.fresno-tdi

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95 Eurovan EVC camper with 98 AHU engine (VeganVan02); 01 Jetta ALH engine and parts - waiting for transplant into 97 Eurovan (VeganVan03);05 BEW Beetle
Good question - My friend called a bit ago after having talked to several shops (and shown the block to them). They've said it can't be welded without taking the head off and the pistons out. I don't know enough about the temperature effects of welding a Pasat block to know why this would be necessary, but my friend took it to two or three shops and they all said the same thing. I don't know if it is the type of welding that is the problem, or the block itself...
Ken
 

GetMore

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1997 Passat TDI, 2010 Jetta Sportwagen
The proper method for welding cast iron involves preheating the area of the weld. Ideally the block would be brought up to temperature (glowing red, IIRC) and kept at that temp while it is being welded, then allowed to slowly cool.

Not cheap, quick, or easy.
 

pinehead

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May 19, 2003
Location
Treasure Coast, FL
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Passat
Lock And Stitch

What about a lock and stitch?

There was a problem on some of the Brazilian Cummins ISB blocks that cracked in the water jacket on the side of the block (IE: 53 block).

The crack can be repaired by drilling small holes all along the crack, then inserting small screws to repair the area. Very strong and very effective.

In your case a small drill hole at the top and bottom of the crack may buy you some time until you figure it out.

Here is a link to the Cummins ("Old") problem and the fix:

http://www.stamey.nu/Truck/Cummins53BlockFAQ.htm

There are quite a few pictures so be patient.

If you need more info. give me a shout and I will send you what I can find. A good internet search will probably yield some info. on this too.

AJ
 
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GetMore

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1997 Passat TDI, 2010 Jetta Sportwagen
The lock and stitch method is only good for plugging a leak, it does not add structure.

This crack is a structural problem. I'm getting the impression that the transmission alignment is changing due to this crack.

Drilling a hole at each eld of the crack will help keep it from spreading.

The only other option I can think of is to install a bracket to reinforce that tab.
 

jayp111

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Undisclosed location
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GetMore said:
The lock and stitch method is only good for plugging a leak, it does not add structure.

This crack is a structural problem. I'm getting the impression that the transmission alignment is changing due to this crack.

Drilling a hole at each eld of the crack will help keep it from spreading.

The only other option I can think of is to install a bracket to reinforce that tab.
I have no experience with the product but take a careful look at the catalog @ http://www.locknstitch.com/FT pdf files/LOCK-N-STITCH Crack Repair Cat 2007.pdf

They have a lot of products and literature that state pretty clearly that this type of repair is well within the intended application range for this product.

Looks like a great product to have in your bag o tricks....I definately bookmarked the page....
 

pinehead

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Location
Treasure Coast, FL
TDI
Passat
GetMore said:
The lock and stitch method is only good for plugging a leak, it does not add structure.

This crack is a structural problem. I'm getting the impression that the transmission alignment is changing due to this crack.
The reason I posted this is specifically for a "Structural" problem. The "Locks" actually Pull the crack together and and strengthen the area in and around the crack.

This method is not just used for "plugging leaks". Although it could be used in that application.

The only down side would be if you are trying to do a repair in an area where it is very round. Or in an area that is hard to access. If the component would have to be removed to do the repair..... It would probably be more cost effective to replace the affected part where applicable.
 

redtdi966

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bridgewater, NJ
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09 B-graphite sedan 6-sp (Bridgewater- NJ)
There is no right way. Take your pix to welding shop..

It is a no win situation, If you bolt up tranny and clean off the JB, then have shop beef up area slowly. Arc welding in short spurts will not warp area. The block is a huge mass.

Again you have a no win situation, and three shops don't want to touch it.

Sorry to hear all this, how could this break other than a crash?
 
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P2B

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Toronto & Muskoka, Canada
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redtdi966 said:
If you bolt up tranny and clean off the JB, then have shop beef up area slowly. Arc welding in short spurts will not warp area. The block is a huge mass.
I agree, this is definitely worth a shot.

I used arc welding to repair a very similar 'tab' on the cast iron handle of a hand-operated water pump - must have been at least 8 years ago now, and when I used the pump tonight the weld looked as good as the day I did it. The repaired part takes a lot of stress since the weld is 1/2" from the bolt hole that holds the pump rod, which in turn lifts water 30'. This is a public water pump, and is used a lot because it's the best drinking water for miles around.

The tab was broken off completely before I repaired it. I have very little welding experience, and had never welded cast iron before. I went to a supply store, showed them the problem, they told me it really should be done while red hot, but sold me some rods to try, said these should work if you use multiple passes and build it up slowly.

If it was my car, I reckon I could do the same thing I did on the pump. You just need to find a welder willing to take a shot at it.

Simon
 

GetMore

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Patterson, New York
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1997 Passat TDI, 2010 Jetta Sportwagen
I take back my statement. I thought it was just another name for the plugs.

The plugs just seal cracks, but the locks add structure..
 

fastvicar

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Lancaster, PA, USA
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1996 Passat, Indian Red
Find a welder with a good reputation. Welding castings takes a lot of experience. I'd steer more toward a mobile welder with a truck that can come to you since they often are called to constructions sites to do repairs on large equipment that use a whole lot of castings. Ask around your blue-collared neighbors.
 

sassyrel

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aplington,iowa
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passat,96,black-metalic
have welded a block more than once--set a known straight piece of angle along the bellhousing area--after you take that piece loose--and vee the snot out of it----then clamp that angle across the bell area--and clamp to the broken piece--then have the welder you hire--to weld it with NICKEL rod--not stainless--or use a GOOD cast rod--those blocks are hard!!!!!!! if he welds it slow--and only a bit at a time--then peens the weld quickly before it cools--you wont break that piece off again----been there--want to bring it up here in iowa????:D :D just make sure the piece is in the right place so the dowel pin lines back up!!!!!since the other trans is junk???????? could cut the front half of it off--and use it as a clamp piece--then youd know the alignment was right--------also--it doesnt need preheat this way---and---jbweld--for that stress spot--some people are real winners---
 
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fastvicar

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1996 Passat, Indian Red
sassyrel said:
jbweld--for that stress spot--some people are real winners---
I have a hard enough time trusting epoxies for port-fills in my two-strokes (which are unstressed points). They're strong, but not that strong.

Good advice on the rod choice--and don't forget to "V" it good & properly. Make it ugly before you make it beautiful.
 

sassyrel

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aplington,iowa
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passat,96,black-metalic
fast--it can be both good--and pretty also--course depends on the welder--ive seen lots of chicken tracks!!!!!!!!!!!!!!!!!
 

ken.fresno-tdi

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Location
Fresno, CA
TDI
95 Eurovan EVC camper with 98 AHU engine (VeganVan02); 01 Jetta ALH engine and parts - waiting for transplant into 97 Eurovan (VeganVan03);05 BEW Beetle
Thanks for all the great advice. I think I will try the welding option first - The engine is now removed from the car, so I have easy and clear access to the point. How did the crack get here? I can only guess - which is that it must have been in some kind of accident. Since I bought the car through a dealer auction there is only the evidence of the car itself. The RF fender was replaced, and several other trim items - but the car looks in good shape, which makes me think the previous owner was trying to fix it up but gave up. The transmission was a junkyard special (crack in the housing, with yellow markings), which makes me think that after they gave up on the engine they swapped out the transmission to sell it or put it in another car. The engine has good compression, and the turbo seems to work, so I am hopeful that if I can get this mount welded it will come together again... But perhaps if the car was so badly treated there are many other issues.... Oh well, someone has to resurrect seemingly dead Passats that hopefully have life left in them....
Ken
 

sassyrel

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aplington,iowa
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passat,96,black-metalic
ya--and--at only 58,000--if its correct--that thing has LOOTTSSSSSSSSS of miles left in it!!!!!!!!!!!!!!!!! alswo--if the belt aint been done yet--your right at due for a timing belt---
 
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