I watched a guy stitch a block on a 6 cylinder Mack engine. When he was done you could hardly tell it had been cracked. Didn't look to hard just time consuming even with air tools.
Cracked 2F block-Should I weld?
- Thread starter vtcruiser60
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Bodean
Hot Damn
I've got a buddy that had a SBC that cracked due to the cold and he used some block sealer. He added that to the water and ran it for a while and never had a problem in a 1/8th mile bracket racer. That was 2 years ago and the motor is still running today with no leaks! Just my .02
As I've discussed in the past, I have a crack in my F engine as well. Showed up after my episode with the blown head gasket, when I cleaned out the water jacket. (I won't ever know if the crack was there before I cleaned the 4 inch deep crud/silt/whatever that filled that corner of the block, or if it resulted from the loss of coolant. In some ways, I now wonder if the "silt" was a PO's fix for the crack.)
At any rate, after thoroughly flushing the system twice, I have tried 2 different types of block sealer to no particular avail. I also have plastered over the crack with both regular and quick dry JB Weld. I have had partial success, in that I have not needed to add coolant for months at a time, but it still dribbles out.
The problem is, the crack is only visible when the engine is hot, at least while the engine is installed and the manifolds are in place. It also only leaks when the engine is hot: what dribbles out evaporates before it ever hits the ground, so I have no puddles, or even drops.
But I know it leaks, and that bugs me. So, when the time is ripe, and the weather is a bit warmer, I will go the muggyweld route. Grooving the crack (and drilling the ends) has to be important.
At any rate, after thoroughly flushing the system twice, I have tried 2 different types of block sealer to no particular avail. I also have plastered over the crack with both regular and quick dry JB Weld. I have had partial success, in that I have not needed to add coolant for months at a time, but it still dribbles out.
The problem is, the crack is only visible when the engine is hot, at least while the engine is installed and the manifolds are in place. It also only leaks when the engine is hot: what dribbles out evaporates before it ever hits the ground, so I have no puddles, or even drops.
But I know it leaks, and that bugs me. So, when the time is ripe, and the weather is a bit warmer, I will go the muggyweld route. Grooving the crack (and drilling the ends) has to be important.
My Dad had the same problem on a '64 Datsun pickup. He kept coolent in it, didn't runit hard, and lived with the problem for quite a while. I'd try the Muggy weld. The video is very impressive (and it even looks easy). As wth ALL welding...work clean! What do you have to lose...it's already cracked... Just my .02.
The term "freezeplug" is pertinent here. They're designed to give way when the coolant expands by freezing. This makes me wonder if the cold caused your crack and not the (must have been severe) overheating.
If it were mine I'd probably buy some cast iron rod and try stick welding it - I think Lincoln sells one type of rod specifically for the use. There may also be a wire spec'd for cast iron too but I've never heard of one. It would need VERY careful prep work to clean and bevel/groove that crack before trying to weld it.
I'd stay away from stopleak type products. Not only is this too big for them but that stuff can end up throughout your cooling system and clog radiator passages or ruin the head gasket sealing. I pulled the head from my '65 yesterday because it had a 100 lb cylinder. There is a silvery coat of something on the old gasket, head surface, and block. I don't know for sure, but while wondering about it it occured that my PO might have used a stopleak.
Whatever you end up doing, invest in a block heater. They should be common and cheap up where you are - usually replaces one of the freezeplugs and plugs in to household circuits.
If it were mine I'd probably buy some cast iron rod and try stick welding it - I think Lincoln sells one type of rod specifically for the use. There may also be a wire spec'd for cast iron too but I've never heard of one. It would need VERY careful prep work to clean and bevel/groove that crack before trying to weld it.
I'd stay away from stopleak type products. Not only is this too big for them but that stuff can end up throughout your cooling system and clog radiator passages or ruin the head gasket sealing. I pulled the head from my '65 yesterday because it had a 100 lb cylinder. There is a silvery coat of something on the old gasket, head surface, and block. I don't know for sure, but while wondering about it it occured that my PO might have used a stopleak.
Whatever you end up doing, invest in a block heater. They should be common and cheap up where you are - usually replaces one of the freezeplugs and plugs in to household circuits.
vtcruiser60
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- #26
I spoke with the welder this morning and he agreed to take a look. The likelihood on the weld being good and holding depends, in his opinion, on his accessibility to the crack. I told him I would pull my fender and wheel well off so he can get a good look. He has repaired numerous engines before and accessibility seems to be the main issue. He said it will run about a hundred bucks, if he thinks he can do it right.
I didn't bug him about his techniques...stitching or other, I just figured it would be good to have him take a peek first.
Someone mentioned freeze plug failure as a cause for this problem. I have always thought that freeze plugs were incorrectly named. Freeze plugs fill holes that allow manufactures to remove and clean casting materials during the engine casting process. Given that water jackets usually burst due to freezing, I would say that freeze plugs are not designed to pop. But look at me.....like I am the expert now.
I appreciate the advice from the board. The epoxy might work work fine. I might slap it over his weld, if he does one. Regardless, I'll take some pictures and share them......so fewer of us have to do this one in the dark....again.
I didn't bug him about his techniques...stitching or other, I just figured it would be good to have him take a peek first.
Someone mentioned freeze plug failure as a cause for this problem. I have always thought that freeze plugs were incorrectly named. Freeze plugs fill holes that allow manufactures to remove and clean casting materials during the engine casting process. Given that water jackets usually burst due to freezing, I would say that freeze plugs are not designed to pop. But look at me.....like I am the expert now.
I appreciate the advice from the board. The epoxy might work work fine. I might slap it over his weld, if he does one. Regardless, I'll take some pictures and share them......so fewer of us have to do this one in the dark....again.
Your welder sounds like a good guy. He isn't making any false promises and he's smart enough not to take a job before he knows what it entails. Also the price is more than fair.
Although I've never seen a freezeplug pop (and have never lived in deep freeze states) I don't see why a manufacturer would place so many of them into a casting just as cleanouts when compressed air can blow out all areas of an unassembled engine block without any access holes at all. It's pretty wide open in there; not big enough for hands always but easily big enough for air or water blasting after the casting is cooled.
Although I've never seen a freezeplug pop (and have never lived in deep freeze states) I don't see why a manufacturer would place so many of them into a casting just as cleanouts when compressed air can blow out all areas of an unassembled engine block without any access holes at all. It's pretty wide open in there; not big enough for hands always but easily big enough for air or water blasting after the casting is cooled.
No freeze plugs are "supposed" to fail in the event your coolant expands under the pressure of freezing, so your head and/or block won't crack. "Supposed" being the operative word. On some blocks there are pockets that trap water, that if frozen will crack in that area. I don't know if the 2F has any such pockets. Also, the location of the crack is a little odd to me, down at the base of the block near the block drain plugs if I am understanding you correctly. Anywho, good luck with it and hopefully the welder will get it sealed up for ya. And if he does keep an eye on you temps. Oh one last thought, what does your oil in the crankcase look like ? If you also have a crack that is allowing coolant into the crankcase...It would be time to reconsider the above fix. Again. good luck with it.
vtcruiser60
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- #29
For those following....I took the driver's side fender off, I got the block clear of the exhaust downpipe, EGR cooler line, various vacuum annoyances. I have a call into the welder and hope he appears this week.
Much to my luck, I also noticed a fair amount of blow by on a visible section of the exhaust manifold gasket.....I suspect the exhaust manifold is not seated right or a bit warped.
I am going to try and post some pictures of this crack for references.
Much to my luck, I also noticed a fair amount of blow by on a visible section of the exhaust manifold gasket.....I suspect the exhaust manifold is not seated right or a bit warped.
I am going to try and post some pictures of this crack for references.
I am very interested. I have not fixed my block yet (slow leak, and I am waiting for welder friendly weather). I am planning on Muggyweld (even have the sticks ready to go). But it keeps snowing.
vtcruiser60
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- #31
Yeah...you might want to wait a bit on stitching. The welder said he was planning on brazing the crack. The effort requires die grinding the crack and brazing. He said stitch welding with an arc requires pretty careful preheating activities. He said he can control the heat better with the torch and brazing does not require such an intense arc heat. He added that with an arc, the crack may run.
MOre to come....
MOre to come....
vtcruiser60
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- #32
Pictures added, 4/24/05
Watching carefully!
Yeah, that crack is right where mine runs.
Yeah, that crack is right where mine runs.
I've ordered and used the Muggy Weld product on an aluminum part that would have been difficult to get at with my TIG welder. The Muggy Weld product worked great and will require minimal machining to have it match back to the original.
BTW...I'm not in any way connected financially or socially to the people at Muggy Weld; just a customer.
BTW...I'm not in any way connected financially or socially to the people at Muggy Weld; just a customer.
vtcruiser60
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- #35
Update 4/27/05
The welder worked over the crack for about 4.5 hrs yesterday. I'll list the steps below:
1. Grind crack with 4 1/2 angle grinder at 90 degree angle to crack. Basically, he dug a trench in the block.
2. Drill hole at ends of crack to relieve stress.
3. With die grinder bevel out "V" shape or "U" shaped trench along crack line.
4. Wire brush the crack and surrounding area with knotted wire brush on the angle grinder.
5. Tack weld the crack at 2 inch intervals.
6. Weld.
7. Grind
8. Weld
9. Grind
10. Weld
11. Grind
Now he ended up using an arc welder with rods designed for cylinder head repairs (high in nickle) for most of the welding. He did not torch preheat or cool down (w/insulation) as he said these rods were much better than what was around before. He said taking it slow between runs was as productive as preheating with a torch. This practice balked against conventional wisdom, but I trusted him. After each run, he would seemingly grind out 75% of the weld, and weld it again, making layers along the crackline.
Towards the end of the grinding, we heard a distinctive chinking sound and observed a new crackline about 1 inch long. The proved tricky to finally weld shut, but structurally everything looks good. We filled it with water, observed several pin holes, drained the block, welded again, filled it, until the pin holes were closed. Water is not dripping anymore.
However, there seems to be some residual seepage around each end of the former crack line. This looks like a black area of moisture within the dust of a weld. I plan on filling these areas, and the overall weld with some epoxy or perhaps JB weld just for added insurance. I am confident that this will take care of the problem.
I'll post pictures when I do this.
The welder worked over the crack for about 4.5 hrs yesterday. I'll list the steps below:
1. Grind crack with 4 1/2 angle grinder at 90 degree angle to crack. Basically, he dug a trench in the block.
2. Drill hole at ends of crack to relieve stress.
3. With die grinder bevel out "V" shape or "U" shaped trench along crack line.
4. Wire brush the crack and surrounding area with knotted wire brush on the angle grinder.
5. Tack weld the crack at 2 inch intervals.
6. Weld.
7. Grind
8. Weld
9. Grind
10. Weld
11. Grind
Now he ended up using an arc welder with rods designed for cylinder head repairs (high in nickle) for most of the welding. He did not torch preheat or cool down (w/insulation) as he said these rods were much better than what was around before. He said taking it slow between runs was as productive as preheating with a torch. This practice balked against conventional wisdom, but I trusted him. After each run, he would seemingly grind out 75% of the weld, and weld it again, making layers along the crackline.
Towards the end of the grinding, we heard a distinctive chinking sound and observed a new crackline about 1 inch long. The proved tricky to finally weld shut, but structurally everything looks good. We filled it with water, observed several pin holes, drained the block, welded again, filled it, until the pin holes were closed. Water is not dripping anymore.
However, there seems to be some residual seepage around each end of the former crack line. This looks like a black area of moisture within the dust of a weld. I plan on filling these areas, and the overall weld with some epoxy or perhaps JB weld just for added insurance. I am confident that this will take care of the problem.
I'll post pictures when I do this.
Running short beads minimizes the heat input, which makes it less like to crack. Peening the beads while they are still hot helps to relieve stress, so it is less likely to crack. Nicke rod is correct as it is miscible with the carbon in the iron, so it won't precipitate out as martensite (iron carbide). Sounds like he did ieverything right.
Good luck
Good luck
if it's a water jacket leak, bondo holds up for a long time also, or JB weld. JB weld is holding my dad's outboard motor together right now, he broke everything that he could get a hammer and a punch under trying to get the powerhead off, but JB weld and a file fixed it. ran fine afterwards.
vtcruiser60
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- #38
Pinhead, thanks for the reminder. He peened the difficult welds for 2-5 minutes after welding....holding his workglove over the weld in between. I believe this was to slow down the cooling process. The peening would have relieved some of the stress, I believe. Forgot to add that....
Hope to get either the epoxy or jb weld on the block this weekend. Then I am off to the radiator shop for the mother of all flushes. Might have them work on my arse at the same time. Damn experience has me all pent up.
Hope to get either the epoxy or jb weld on the block this weekend. Then I am off to the radiator shop for the mother of all flushes. Might have them work on my arse at the same time. Damn experience has me all pent up.
vtcruiser60
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- #39
I spread JB weld liberally across the weld, and about a half inch beyond the welded area this weekend. Prior to application I took a grinder and wire brush to the area and cleaned it furiously removing slag and grime.
The next day I filled the radiator and block with coolant and water and I don't have any seepage. I'll get the exhaust and EGR lines back on this coming weekend. Seems to be working.
I have also scheduled to take the rig to a radiator shop for a power flush.
The next day I filled the radiator and block with coolant and water and I don't have any seepage. I'll get the exhaust and EGR lines back on this coming weekend. Seems to be working.
I have also scheduled to take the rig to a radiator shop for a power flush.
I'm hopeful. It sounds like by doing the prep (taking the fender off), he'll be able to take care of your problem. Good prep almost always ends in a job well done.
