All MetalShaping

All MetalShaping (https://www.allmetalshaping.com/index.php)
-   Welding Sheet Metal (https://www.allmetalshaping.com/forumdisplay.php?f=52)
-   -   Brazing/soldering question (https://www.allmetalshaping.com/showthread.php?t=20175)

idickers 12-18-2020 10:14 AM

Brazing/soldering question
 
I apologize if this is not exactly a sheet metal question, but I didn't know where to post. I need to make a repair on a cast iron engine block on a running engine, and am looking for ways to repair without stripping the block down for welding. I started out trying to remove an easy-out that had been broken while attempting to remove a broken bolt. This is in the flange of the block that mounts to the transmission bell housing.

All foreign pieces are now removed, but in the process I removed too much material and have to fill a void that I would like to next drill and tap for a new bolt. Is there a way to use oxygen-acetylene to braze or solder in filler for this type of application? Or to backstop a time-cert?

Marc Bourget 12-18-2020 10:19 AM

Lots of experienced folk on this site have intelligent solutions.


My only experience I hired Holt Bros. to repair the heads of my 6.2L in a heated cabinet.



Of the several solutions I've seen, Kent White has the most intriguing.


I suspect he'll weigh in, soon.


FWIW

crystallographic 12-18-2020 11:16 AM

Quote:

Originally Posted by idickers (Post 166207)
I apologize if this is not exactly a sheet metal question, but I didn't know where to post. I need to make a repair on a cast iron engine block on a running engine, and am looking for ways to repair without stripping the block down for welding. I started out trying to remove an easy-out that had been broken while attempting to remove a broken bolt. This is in the flange of the block that mounts to the transmission bell housing.

All foreign pieces are now removed, but in the process I removed too much material and have to fill a void that I would like to next drill and tap for a new bolt. Is there a way to use oxygen-acetylene to braze or solder in filler for this type of application? Or to backstop a time-cert?

I've welded a lot of cast iron engine stuff.
My company sells this stick-arc cast iron welding rod that is "no-peen, no-preheat" and NOT NI-rod and a pretty good DVD on cast iron welding.
Good Luck,

cliffrod 12-18-2020 11:21 AM

Running engine means it's in the vehicle(?) and trans mounting bolt means bellhousing with hole to be repaired being upon a vertical surface(?)



I do a lot of fill/build brazing rebuilding the sacrificial portion of carbide-tipped chisels. A clean joint and good flux will allow a lot of creativity for what I do, but gravity always wins. Very easy to braze upon a vertical surface and soak enough heat that the entire braze fill mass will simply drop away like the liquid metal that it is. It can be a delicate process. If you can manage the heat sink (might be tough on a large item like an engine) and overcome gravity (which is usually done by rotating the part to capture or contain the molten mass), you can probably fill it and tap it just fine for such a situation.



The other braze option is to make a replacement part with a tighter fit to overcome that loss so you can achieve a sound joint. That would probably be more practical with the engine in the vehicle. You could simply flux & tin both sides of the tight joint separately, then place together in position and heat properly to fuse.

idickers 12-18-2020 11:35 AM

Thanks all, looks like I need to find a welder with more skill than myself. Fortunately, the engine is out of the car on an engine stand, so can be transported.

Chris_Hamilton 12-18-2020 12:17 PM

What about a heli-coil insert? If I understand your circumstances that would seem to be the easiest solution if you haven't removed too much material. Inserts require you to drill oversize anyways or you could possibly step up a bolt size in order to fit the insert if you have removed a lot of material. Worth a look.

Over the years I've done several for Hondas. The "B" and "D" motors were especially bad for this. AL block, AL tranny, steel bolt. Bolt would corrode the threads and strip them when separating the engine and tranny. Heli coil insert worked like a charm every time and lasted the life of the vehicle.

idickers 12-18-2020 12:18 PM

That was my first thought. In fact, it might work with a big-cert, the over-size version of time-cert. But I'd still have some gaps to fill.

norson 12-18-2020 04:54 PM

How about drilling and tapping it for a pipe plug. Pinning it to locking it in place, then drilling and tapping it to stock.
OR, one time I replaced 3/8" bolt with a 7/16". Hell, one time I used a longer bolt and nutted the back side.

crystallographic 12-21-2020 12:44 PM

Quote:

Originally Posted by norson (Post 166223)
How about drilling and tapping it for a pipe plug. Pinning it to locking it in place, then drilling and tapping it to stock.
OR, one time I replaced 3/8" bolt with a 7/16". Hell, one time I used a longer bolt and nutted the back side.


Right-o - a big enough pipe plug would tap into a huge hole, and braze up a plug and drill and tap that, and then wind it in with some locker-gloo.

Bam! Done!


All times are GMT -5. The time now is 03:11 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.