JB Weld?!

[278]

I just sent you a PM but yeah basically if your just compensating for the 4mil that all you really have to do

[bholmes]

Got the PM, good info, I really appreciate it. I also talked to Brandon at WildCard and he had alot of useful information. really for a 4mill and going with a trail type port all you need to do is raise the exhaust port up a bit, such that you're around 26.5mm ish below your TDC and the transfer ports are almost already where you want them. Brandon said that I could really just leave them alone and mod the ehxuast port and lower my port floors to meet the piston at BDC and wind up with a descent running machine. Of course be mindful of where your transfer ports are pointed, but nothing to suprising there. Aim the roof of the port upwards to allow a broader spread and leave the port walls alone. Then mill my head to clear the piston and I should be in buisness.

[278]

Yeah Brandon and his wife are great people to work with and they know their stuff. Sound about right as far as the porting. Good luck with the build man and if you have anymore questions feel free to ask.

[Ieat4strokes]

Papsmurf - hmmm that's wierd, almost everytime I used it it never held up for long. I've tried to seal cracks in a 250r case I use to have and a 350x I had the chain came off and well u know the rest. The thing leaked oil like a sive and it didn't work on that either. Maybe I'm prepping surface wrong??? Lmao like I said my experience with it lmao

[papa_smurf49319]

Maybe it doesnt hold up to the fuel, like i said this was in a wet sump on a small block chevy.

[bholmes]

JB weld actually holds oil in my super bike. I laid it down this past summer and cracked part of the case and it would blow oil out. I JB welded it up good and haven't had a problem since. I've prob put 5k miles on it since. For me the trick it not just patching the hole or what ever, but smearing it all over. The more area I have it bonded too the less likely I am too have a leak. It may be oil vs fuel like Papa said though. Fuel is much less viscous than oil and would therefore leak much more easily.

[broncbob]

I have bad news for you.....I have the drain plug on my diesel heater in my garage JB welded. The original drain plug was some kinda rubber joke that came apart when I went to drain the tank.

 

I got a brass pipe bushing with a pipe plug, threaded it in the drain hole, and the sealed it with JB. It has been holding for a good long time now. JB stands up to what it claims, but you have to follow the directions to the letter.

[Ieat4strokes]

That's probally my issue then, the few times I've used maybe left a oily film on parts and reason why it wouldn't stick well. I mean it was as hard as a brick, just like it wouldn't stick to the cases. Would work for a few days then I'd notice a small leak, after I picked at it to inspect it flakes off. Hmmm. Mechanic error. Lol

[broncbob]

I normally rough up the surface to be bonded, such on the tank on my heater, I used a 120 grit wheel on a die grinder, but I did nothing to the bushing. I figured the threads would give it something to grip to. I then cleaned them with brake parts cleaner.

 

I did fix a hole punched into a case cover, the clutch side on one of my dirt bikes. I roughed up the surface with 120 paper cleaned it with acetone, and then painted it over with the JB. It held very well for years, till I lost the bike in my divorce.

 

The other big thing is not to rush the part back into service, you have to let it cure for a full 24 hours, longer if make a big thick repair.

 

I have only made one real structural repair with JB, it was on a very old outboard motor, It had cracked a seal/bearing retainer. One of the ears that bolted it to lower end broke off, and it was cast aluminum. Welding it wasn't a option, and finding a new or a good used one was going to be a long search, so I JB'ed it, and it worked like a champ! It lived for 2 years that I had it under heavy use exposed to gear oil on one side, and water on the other.