JB Weld re. Aluminum

[3930dave]

Hiya,

Not trying to insult real welders with a JB post here.....just wanted to get this question in front of people who have been playing with metal for "a while".

I need to fix a minor problem on the exterior of an aluminum head.

A wise wrench I trust recommended JB for this fix (makes sense to me), but also added that I should look for the JB version that is optimized for Aluminum.

Looking at the JB site, I can only see their generic version listed. The generic JB is listed as working on Aluminum, but I don't mind chasing down a better version.

Is my buddy remembering a variant of JB that doesn't exist anymore, or is it a industrial product that is not listed on their public site ?

Best Rgds, Dave.

 

[whistlepig]

Devcon is the best for metal repair.

 

[Bedlam]

ITW Devcon | Permatex | OEM Adhesives | Maintenance, Repair & Operations (MRO) Products

 

[3930dave]

Thnx for the note WP..... I've liked the Permatex products I've used the last # of years, looks like Devcon is the same corp.

The name rings a bell, but it was many years ago I would have used a Devcon product, so am not familiar with the current offerings.

Their site does list an Aluminum epoxy, I'll try to find it locally.

Best Rgds, D.

 

[yomax4]

The best I have used and sold is called Lab-Metal. Also a product sold by Harris called Super-Weld. Lab-Metal is the only one ( as far as I know ) that contains Metal pigments. It sparks when you grind it. It still may be Epoxy Based like all the others. All you need to worry about is expansion and contraction because of the heat. If the repair is in a combustion area, Tig Weld it. Or better yet, Tig Weld it anyway.. Good Luck..

 

[3930dave]

Thnx for the options Yo.... the smallest Al. epoxy I've seen listed is 1lb, and that is a "bit" more than I need, so will check yours out too.

The issue on the head is with something like a frost plug (same idea, just smaller, about the diameter of my pinky finger). I have a slight seepage, from the water jacket.

A buddy (who has worked on a bazillion of these particular engines) has recommended super cleaning the exterior aluminum (he has the right tools) and filling this area level with a good Aluminum epoxy. Seems a reasonable approach for me to pull off, given an epoxy that is a thermal/chemical match for aluminum.

I want to try this epoxy approach, b4 trying to physically replace the plug.... don't have the resources to get into any serious welding/machining at this time.

This old engine has been good to me.... just hoping to keep the coolant where it can do its job..... :thumbsup:

 

[E/S]

Have you tried adding Alumaseal to the coolant system ?
I have had good results with it on aluminum.

E/S

 

[s78wingrider]

I always clean with denatured alcohol right before applying anything. Aaron

 

[user.69169]

This JB Weld against Devcon thng stirred my curious up so I went looking at both websites.
Now Devcon does make a lot of different epoxys, I know their bronze one has made a good number of emergency bearings to get machines back running when the bearing was a month away, but when you get right head to head JB - Devcon, JB Werld comes up a winner.
JB has a higher temperature range, and is equal in strength to Devcon.

About the main drawback to JB weld is those dang little tubes don't seem to be big enough for the job at hand.
Then again once you open up a can of Devcon the second time to use it the dang stuff is a rock in the bottom of the can.

 

[whistlepig]

We use Devcon for industrial repair of castings. And have done this for decades. We wouldn't even consider JB Weld. We would have no reason to.

 

[3930dave]

I'm reluctant to use antifreeze additives, except as a last resort. Some of the modern ones may be decent, but I'd prefer to plug the leak externally if I can. I'd like to see specs on the additives effect on thermal performance - not likely to be found on a consumer product, maybe for an industrial one ?

I like using alcohol for cleaning..... relatively safe to handle, works fairly well, and leaves no residue. (Recently read the thread here about Welding+Brake Cleaner - expected a fire story, not a scenario out of WWI trench warfare ! REAL scary part of this is the hazard is not well known at all..... of 2 guys (both sharp) I know that have been welding for a long time, neither one had heard of the phosgene risk. This horror story has given me another good reason to use alcohol for cleaning).

I'll give this fix a go, with a decent Aluminum tuned epoxy, and keep an eye on how it holds up.

Thnx again, for all the inputs..... Rgds, Dave.

 

[gauthier]

That stuff is pretty amazing really,just last week,had a leak in my 1996 toyota tacoma's wiper tank hose,smeared some jb weld on it and the tank now holds water,[rubber hose off bottom of tank]..

Stopped a rear end leak on aluminum rear axil housing with jb weld,on a lawnmower I'm still using 10 years later.

 

[BrentD]

I've been wondering if JB Weld might fix a coolant leak in a cracked lower intake manifold on my Pontiac Aztek. At this point, I need the car up and running ASAP and don't really want to spend any more money on the motor that is in it. I'd like to keep the thing running until I can afford to swap the 3400sfi for a Supercharged 3800 Series II.

 

[yomax4]

It should handle the low pressure. May not handle the heat. If you can just try it on the car, Try it. If you have to take the manifold off, Weld it.

 

[travis potter]

I used JB on a old air cooled VW to repair a hole in the top of the block it worked good didn't leak oil for as long as I owned it.

 

[coreshot]

I built a gas tank for my rock crawler out of an aluminum tank out of a boat. It required me to cut the tank in half, and tig weld an end back on it. There were also a few bungs for fittings that had to be welded in. Two of the bungs had small pinhole leaks in the welds, so I smeared regular JBWeld over the beads. It hasn't leaked a drop in 7 years.

 

[Rob-D]

Just my view after doing lots of machining I'd try tapping it and putting in a plug with a good sealer if you can get to it.

my two cents.
Rob

 

[Soundguy]

I honestly think the 'patch' method is the wrong approach.

if this is some sort of 'frost' core, welch, or other type of plug, including dimple to expand plugs.. I'd pul the old one, clean the seat.. if there was pitting, I'd clean and fill with hi temp rtv.. or heck.. even the epoxy.. smooth allow to cure, then insert the plug with some sealer on it and set it.

that would be a superiour fix to smearing a handfull of glue over a seeping 'replaceable' plug.

soundguy

 

[3930dave]

Went with JB yesterday..... my buddy cleaned up the area/old plug pretty well, using a die grinder and a burr.

I left the car to sit for about 6 hours (other stuff to fix too), before installing new Prestone to replace what I drained out.

Seems to be holding v. well today, will keep an eye on it.

Generally, I prefer to take the high road, so I do hear you Soundguy. Decided to make this trade-off for a few reasons, first being the mechanic that recommended this.... been working with him for 10+ years, so I trust what he suggests (that is not a statement that I ever make lightly, about anything, but esp. vehicles). The plug seemed to actually be rusting from the outside/centre (I do change my AF about every 3 years, and use Prestone long life), so I was not overly concerned about the seat area. Given a reasonably clean area to work with (check), the JB at 600F/3900+psi is overkill for what I needed here.

(I've talked with people who have successfully re-built exhaust ports with JB.... way beyond what it is spec'd for, and not something I'd care to try, but it does seem to be a decent product, for what it is).

I needed to get this fixed/back on the road in an afternoon, and parts for this vintage of Volvo (1989) are getting to be a pain. This plug is not a standard block plug, rather about a 1/2" sized plug in the head. Volvo Canada was eradicated (literally) 2 weeks ago, the whole building is empty/dead. I've heard of of Toronto dealers with 20 customer cars sitting in their lots (for days) waiting for parts to ship in from Atlanta.

Ford is doing balance sheet cleanup for China Inc., so it is only going to get worse, both in delays, and older parts getting EOL'd at a faster rate.

I wish I had the time/shop/skills to properly fabricate many things myself.... but..... JB semi-skillfully applied is a whole lot better than what most people would have done with an old ride like this.... just ignore it......

I've been impressed with this JB, so far, here is hoping my luck (and the JB) holds.

Rgds, and thanks for all the inputs........ D.

 

[aczlan]

I needed to get this fixed/back on the road in an afternoon, and parts for this vintage of Volvo (1989) are getting to be a pain.

Out of curiosity, what model Volvo is this? Which engine does it have?

We have had several 700 and 900 series Volvos in the family and also 2 V70s, a S70 and an 850. Years range from 1985 (760 Sedan with a Turbodiesel) to 2003 (V70)


Aaron Z