Epoxy or filler for exhaust chest ?

[olboatman]

Wondering if there are any hi-heat resistent fillers that I could use to clean up some pockets and smooth out the flow in an exhaust chest ? Thanks for any info! Gary

[RBT]

Subscribed.

[roadkill636]

Mite check out Aluminox

[olboatman]

Mite check out Aluminox

Roadkill do you know if it has been used around exhaust ports? I can't find a max temp usage on their product discription . Everything else about it sounds good for the job. Thanks Gary

[CNC_Guy]

http://www.freemansupply.com/LabMetal.htm
The high temp is good to 1000 deg. I've used it on aluminum core boxes with good results at about 800 deg..
Dave

[HStream1]

The correct way to do what you are asking is TIG the pockets and resmooth. I use Lab metal all the time on parts I coat that will be subjected to high heat. But I wouldn't gamble using it in an exhaust chest.

[olboatman]

The correct way to do what you are asking is TIG the pockets and resmooth. I use Lab metal all the time on parts I coat that will be subjected to high heat. But I wouldn't gamble using it in an exhaust chest.

Thanks Hstream1 I knew after my last question(polishing pistons and heads) you would chime in. Like the rest of life the easy way out is usually not the correct way. I enjoy doin some mods. in my workshop when I am capable---time to learn to weld!! I guess my "bright Ideas" are NOT always that bright! Thanks to all with the info offered. Gary

[HStream1]

One more thought Gary. If and when you do decide to weld those pockets. That Block will need to be Boiled in dawn Dish soap to open up and remove all impurities that have impregnated the pours. Then reboiled in Fresh water. Then it should be placed in a Oven at 400 degs to completely out Gas. This is done with the cylinders facing up. If not the sleeves stand a chance on sliding/moving. This will assure your weld has clean metal to penitrate. Its something I have to do when I coat Used pistons that have been subjected to fuel and oils.

[Mr. Demeanor]

Theres nothing that will work. Even if it has a high enough heat rating, the extreme changes in temp will cause it to seperate from the aluminum and God forbid it goes the wrong way.

[olboatman]

Chris That makes sense and Bud I will keep that info(thanks for sharing your work procedures) in my notes for the future--- that cleaning method should also be helpful for adding epoxy to intakes. The more I ask the more I learn.Thanks again guys ! Gary

[Onetime]

Many years ago did it with epoxy but it won't last in the exhaust chest. There are some high heat ones that last long enough to do a few Dyno pulls. Allows you to see if what you're doing is going to make more power. Then take it apart again and duplicate it with weld.
Usually on the Mercs it would distort things and needed to true the cylinders after the welding.

[wired247]

ER4043 out of a spool gun DCEP would be the way to go. TIG welding is going to transfer too much heat to the parent metal. You'd be surprised how much ER4043 you can lay down as a filler and put your hand on 3 seconds later. Any epoxy will lose its chemical bonds and gone in minutes or hours at the most.

[HStream1]

There are proper welding procedures in place that if followed correctly will not cause damage to the block or distort when Tig Welding Aluminum. (1) Pre Heat, (2) Heat controlled interpasses, (3) controlled cool down. Tig Welding Aluminum 101.

[wired247]

True, but all of those require considerable heating of the parent material. In non structural welds involving interference fits such as sleeves and the like Ive found it a lot simpler and more efficient just to grab the spool gun. If I'm trying to seal a crack in an aluminum pipe or block in a stressed area, its going to get TIG welded with the appropriate heat conditioning. Anything structural is going to get the same considerations. For non structural work such as building up material in cylinder heads where I am trying to keep warpage to a minimum and there is no loading involved I'll grab the spool gun 10 times out of 10. Makes for an easier, faster and cleaner weld without the potential for disturbing interference. I suppose its personal preference .

[roadkill636]

Just got an email back from evercoat


None of our products will withstand those extreme temperatures. The Aluminox epoxy has a maximum temperature of 260 F.




Thanks,
Jacqueline Becker
ITW Evercoat
Customer Service/Technical Support