crack in block
 

I have 1,100 miles on my newly restored A. The engine was rebuilt by a professional builder but a crack in the front of the block has appeared. I am guessing that it was not magnafluxed. I have it in a climate conditioned shop. The crack is up and under the portion of the block that is the upper front flat part and is 3-4 inches long. Sorry I cannot describe the location better, but this location makes me think it is a water jacket to the exterior. This is a numbers matching, original engine. I would like to try something other than stitching, but will do that if necessary. It is so darn new, I hate pulling it already after less than a year.

I am thinking about cleaning out the crack and JB Weld for now. Do you suggest that I "pin" the ends of the crack with brass rod so that the crack doesn't run further?

Re: crack in block
 

"V" it out and use slow set JB Weld. The a block is not pressurized and the repair will last for years.

Re: crack in block
 

I like to drill a small hole at each end, J. B . Weld. As Mike said.

Re: crack in block
 

Mike- no brass rod?
Dave- drill hole and put brass rod or JB weld in it?

Thanks fellas!

Re: crack in block
 

Do like Mike V says and vee it out and use the slow set J.B.Weld. Drilling a hole at each end of the crack will keep the crack from spreading.

Re: crack in block
 

Lee Mitch,

Is this the area that you are saying is cracked on your block?

Darryl in Fairbanks

Re: crack in block
 

Hey Lee,
Before you go 'drilling/mudding', I'd show pics of situation here, so something more settled can be said about how to... Your description lets the imagination loose to make maybe bad call/prognosis !

Re: crack in block
 

Yep Darryl, that's the spot and about the length. Brass fix on yours?

Re: crack in block
 

Lee,

Yes, this is a B engine that I repaired about Thirty years ago with 11 solid 1/8" brass pipe plugs. Most people today recommend using Steel or Iron and a Stitch method.

I have never had any trouble and run this engine to this day.

Darryl in Fairbanks

Re: crack in block
 

common location when antifreeze is overlooked

Re: crack in block
 

The old dykes manual called out the use of threaded brass rod, threaded in place, trimmed to within 1/8", then peened over.

Re: crack in block
 

Hi Mike,

I couldn't find Fine Thread Brass Rod, so I settled on Solid Brass 1/8" plugs, plus it is a tapered thread, overlapped 50% on each, start from both ends and work towards the middle. I ground near flush and center punched each to set it.

Had a Dykes Manual and a hardware store close.

Darryl in Fairbanks

Re: crack in block
 

Those old guys sure knew their stuff!! :D

Re: crack in block
 

If it were mine, I'd put in a jar of the regular old BARS-LEAKS & later on, clean the area & paint over it & FORGET about it!! I've seen amazing results, using this product, & freeze cracks were sealed up "indefinitely"!
I feel that drilling, tapping, driving in pins, etc, "might" cause the crack to GROW!
Bill W.

Re: crack in block
 

Just do like Mike V says and you will forget it is there. Take your time and make sure you get it sealed when you apply the JB Weld.

Re: crack in block
 

AND,let that professional know he rebuilt a cracked block!!

Re: crack in block
 

Is it leaking?

Can you tell for sure it' a crack, and not a mold line?

If the block was stripped clean during the rebuild, I'd think a crack there would have been easily seen.

Re: crack in block
 

Yes, it is leaking. That is how I found the crack. Thanks everyone. Where would I be without the fellas on Fordbarn....

Re: crack in block
 

If you use J.B. weld mix up a small batch about the size of a quarter. Wait 20 minutes and mix up another batch that you will use to make the repair. Keep testing the first batch to see when it starts to set up. Then you know when to put the fix it batch on. Keeps you from having to fuss with it to keep it from running down the front of the block. You can also put some masking tape over the J.B. weld when you fill the crack.

Re: crack in block
 

There is also a lot of experience in your local club! :)

Re: crack in block
 

I used a Dremel tool to clean the crack a bit more and used A LOT of JB Weld and held it in place with a bit of masking tape......7 years so far.

Re: crack in block
 

I had a crack near the front of the block and used JB weld high heat.. So far holding well.. Like real welding, getting the area clean and to pure metal is 90% of the work.

Re: crack in block
 

http://www.fordbarn.com/forum/album....ictureid=25146

Professionally done this is what the crack repair will look like.
Have to wonder if they missed this crack what about the others?
http://www.jandm-machine.com/metalStitching.html

Re: crack in block
 

Lee, before you do anything, i'd contact the engine re-builder and ask for a full / partial refund. You probably wont get any, but it doesn't hurt to try.
Then do as everyone is saying and "V" the crack, clean it, and use regular JB weld.
It won't set up very fast and tends to want to sag and run out. Just keep putting it back in there until it starts to stiffen up some. Then take some 80grit sand paper and place the "grit" side against the epoxy and hold in place until hard. The sand paper will give you a texture to match the casting marks on the block.
I did this exact repair as yours on a '29 Tudor I sold a while back, and you could not even tell there was ever a crack.
Good luck. Dave.

Re: crack in block
 

and of course you told the buyer

Re: crack in block
 

Most certainly!;)

Re: crack in block
 

Never ass-ume anything !

Didn't leak for 1100 miles.

Perhaps it was not cracked when it was rebuilt.

Maby it was magnafluxed and was OK.

Things can happen during installation.

Did it freeze up? Overheat ?

This cast iron is 86 years old !

Re: crack in block
 

This is a common place for a crack. Usually caused by freezing.

I have had very good luck when an engine is in the car using K W Ceramic Block Seal. Follow the directions exactly and I have an old radiator I temporarily install as it may partially coat the inside of a good radiator. Thru the years, I have use it many times and most of the time I have had good results.

If for some reason it does not work, you can always try J B Weld or pinning etc.

If the engine was out of the car and on the stand, I may take a different approach but in the car, I would first try K W Ceramic Block Seal.

Again, JMO

Chris W.

Re: crack in block
 

Really? You should re-read my post. Do you rebuild engines by-chance?

Re: crack in block
 

It seems to be an old freeze crack that has opened up. I would use a Dremel with a small diameter bit to clean the crack, and then fill it with JB Weld. I've read several success stories using this method, and if it did fail, then you can always still drill, thread and pin it.

Re: crack in block
 

I had a T head with a nasty 5 inch long crack across the top. V'd it out a bit, JB welded it, then when cured used a grinder and then sander to shape it. After it was painted it was impossible to see and never leaked again.

Re: crack in block
 

Thanks to everyone! It looks like JB weld is the first course of action. I will re-post if it doesn't work. As usual Tom W., I believe you are spot on, but we will never know and it doesn't really matter at this point- just want to drive my A. : )

Re: crack in block
 

Yes Really !

I do re-build engines, but not by-chance. I use precision.

Perhaps you should ask your "professional rebuilder" if he magnafluxed the block.....

Re: crack in block
 

Maybe he did & just didn't see it, in such an out of the way place.
Have you ever made a mistake?--------I've made MANY:D:D:D:D!
Bill W.

Re: crack in block
 

Yes Bill I have however, this is not "in such an out of the way place" and is one of the first places an "experienced rebuilder" should check for cracks.

As was said by "Tbirdbird" in comment # 10..." common location when antifreeze is overlooked ".....

Re: crack in block
 

GOOD point, Mike, I would have been ticked off, also. It doesn't seem common to see freeze cracks here, only hot cracks!
Bill W.