exhaust leak on front left manifold.. Can i just weld this

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candymancan
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exhaust leak on front left manifold.. Can i just weld this

Post by candymancan »

Soo i dont wanna even attempt to try and take off those rusted 10mm bolts on the manifold, and every shop i brought it too, is afraid to do it as well, and they all have quoted me roughly 1,000$ or more and more is if the bolts break off in the head..

So.. I've been attempting to patch this leak with manifold puddys but none of them stick when they dry i can just lift them off the manifold.. even if i prep it really good.

Im trying one more from permatex ment for mufflers, ive used it before and it worked on my other Jeeps muffler for 5-6 years and holds up to 2000f, i put it on this evening and drove around town tonight and no more exhaust leak sound, and looking at it, its sticking and holding and looks good.

But if this stuff doesnt work, im seriously debating about just tack welding the pin hole. Its a fairly big leak, sounds like a horrible dry lifter, and a choo choo train when i drive.. Putting my finger near it i can feel the hot air pushing out in repititions as the valve opens and closes..

Soo can i just weld this to the head ? Im not going to bead the whole manifold, just tack it in that spot for about 2-3 seconds just to plug it. Im not spending $1,000 or 800$ or 700$ or 1500$ on this
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

Kayparkah73
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Re: exhaust leak on front left manifold.. Can i just weld this

Post by Kayparkah73 »

I’ve got a nasty manifold leak too.

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rocklaurence
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Re: exhaust leak on front left manifold.. Can i just weld this

Post by rocklaurence »

There are sticks made just for welding cast metal. They're a little expensive but you can by them by the stick/rod. Just clean/grind it to shinny metal, heat the manifold and then weld it. They have YouTube videos on how to do it.
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Stuka
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Re: exhaust leak on front left manifold.. Can i just weld this

Post by Stuka »

Welding cast can be done. You need a really high nickel rod. Tad did a bunch of tests on this way back in the day.

When you applied the putty, did you wire wheel down the surface first? Assuming you can of course, not sure if is itA place where you can.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

Topic author
candymancan
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Joined: Tue Mar 22, 2016 11:32 pm

Re: exhaust leak on front left manifold.. Can i just weld this

Post by candymancan »

All i have is a flux core welder.. but ive seen a guy on youtube named uncle tonys garage. The guy lives and breathes mopars from the 60-70s and ive seen him weld cast iron heads after he ported them with the same welder i have.

I just worry ima crack my head or something lol. But i think ima give it a try if this stuff i put on break off or something. Its just way too expensive to fix this manifold the (right way) and i only have one leak and its thankfully veey accessable. Its the passenger front port by the alternator right on top too
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

pksjeep
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Location: Washington

Re: exhaust leak on front left manifold.. Can i just weld this

Post by pksjeep »

I do not think welding the manifold to the head will work. I am assuming the exhaust gasket is still partially there, I think this may cause porosity in the weld. Also if there is oil, grease and paint (organic substances) it could cause porosity. I also think the leak would just keep moving around the port until it got welded all the way around, due to distortion and gasket burn out. Possibly valve cover gasket will need replacing after.

If you do decide to weld you should clean the base metals to bare metal, pre heat and post heat the head and manifold. get the proper filler metal and follow the manufacturer's recommendations. Without pre/post heat you do run the risk of cracking the cast material. You will probably need to know if the material is cast iron or cast steel. If you have a manifold to practice on you might try just welding on it and see if it gives the desired results using low heat input. tap on the filler metal spots an see how well they stick to the manifold.
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tgreese
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Re: exhaust leak on front left manifold.. Can i just weld this

Post by tgreese »

No putty/compund will survive. Exhaust manifolds get rocket hot compared to exhaust pipes, and no putty will bond to the inevitable layer of rust.

DIY.

Remove the head and exhaust manifold intact. Take it to your local automotive machine shop and ask them to remove the manifold and surface the manifold. Put back with no gasket. Leaks cured.

Replace the left manifold if you need to. That's the undesirable log manifold on the '80-up models, and there should be plenty of them around.
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Topic author
candymancan
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Re: exhaust leak on front left manifold.. Can i just weld this

Post by candymancan »

I dont have the time or means atm with moving to do anyone more in depth work like that to my jeep.

But i will say this puddy i put on is sticking and surviving fine so far. Its only been 3 days.. but well see how long it lasts. If it can last a month or two months or more before i gatta reapply.. thats fine. I used only a few finger slabs of it on here.. lol and the tube was 12$ .

Also the others that were MADE for this never stuck completetly even when i sanded it down.. they survive the heat but they just pop off in one big chunk.. . They claim to be able to handle up to 2400f. These manifolds probly only get to 1200 or so maybe 1500 ? I cant be sure though.

Here is the leak. And it is now patched with some of this new 2000f puddy stuff. Its working wayyy better then the dedicated manifold puddy that never sticks. its like a silica based puddy. I used alot lol but i wanted to be sure it didnt get passed anything.

Thank god 🙏 engine sounds so much better when its QUIET without that horrible ticking. If you didnt know it was an exhaust leak youd think a lifter was toast

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1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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Stuka
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Re: exhaust leak on front left manifold.. Can i just weld this

Post by Stuka »

Glad it seems to be working for you. Your manifolds should only be in the 500-700 range when cruising. If you hit 1200, its got to be under a very extended high load scenario (long grade at WOT), or, you are running really lean.

Its probably worth tracking down a replacement manifold for when you do have the time to replace it, rather than trying to weld up the one that you have. And just use the putty until then.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

rocklaurence
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Re: exhaust leak on front left manifold.. Can i just weld this

Post by rocklaurence »

OH, I miss-understood. I thought your manifold had a crack... Fixing a manifold crack/leak is do=able by welding but you'll never be able to fix a gasket leak by welding it to the head--no way :shock:

Topic author
candymancan
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Joined: Tue Mar 22, 2016 11:32 pm

Re: exhaust leak on front left manifold.. Can i just weld this

Post by candymancan »

Haha hey it was a thought hah
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

letank
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Location: SF bay area

Re: exhaust leak on front left manifold.. Can i just weld this

Post by letank »

good to know that the exhaust putty is better than the manifold putty... cheers to your perseverance.

I did one of the kid's exhaust manifold with the putty, did not last more than a few days, so I bought one on dabay and upon removal the crack was all around ... 4cyl so it was an easy job... well still a 3hr job because one the bolt hanger was barely accessible.

On the 85 It took me weeks of using all the derusting compound and tools , impact, blue wrench, I drilled some holes in the inner fender to be able to sick a long extension and reach with a breaker bar, to loosen the stubborn bolts... I did not try to known method to go WOT... where on the local streets...
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

letank
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Joined: Wed Oct 03, 2012 9:16 pm
Location: SF bay area

Re: exhaust leak on front left manifold.. Can i just weld this

Post by letank »

Any updates on the miracle product?
thank you
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

Topic author
candymancan
Posts: 3652
Joined: Tue Mar 22, 2016 11:32 pm

Re: exhaust leak on front left manifold.. Can i just weld this

Post by candymancan »

Still holding
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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