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coolant from my exhaust flange bolt?

4.7K views 14 replies 5 participants last post by  Guetter  
#1 ·
Is that normal? I ordered a billet exhaust flange and when I removed the stock flange coolant ran out from one of the bolts. I assumed it had to be normal but I just read another thread and it's got me worried that maybe its not suppose to. please help me so I can sleep easy!!
 
#4 ·
Is that normal? I ordered a billet exhaust flange and when I removed the stock flange coolant ran out from one of the bolts. I assumed it had to be normal but I just read another thread and it's got me worried that maybe its not suppose to. please help me so I can sleep easy!!
NO, not on good quality cylinders...! However not a difficult fix, and since you caught it, you will save yourself a lot of issues, seizures, and bad performance down the road. Use Silicone Sealant or a Threaded Plug to seal the coolant Threaded Hole leak.

Check this thread out:

http://www.trx250r.net/forum/lounge.../forum/lounge/12424-heads-up-cylinder-leaks-causing-problems-engine-damage.html

Carlos.
 
#5 ·
that makes me nervous now, I was having issues with it before I tore it down, maybe my problem wasn't electrical?.. last time I rode it, it was a b!tch to start and it died and couldn't get started again. pretty sure I fouled a plug, but I bought a 01 cr ignition to hopefully solve the problem. it had major kickback too, ohh it was painful. but now I'm thinking I should check the top end and be sure everything looks alright. for a CT 310 kit like I have do I order stock gaskets or get the thinner cr gasket? I always get confused with that stuff because it seems like theres so many different variations I read about.
 
#6 ·
A coolant leak into the exhaust & combustion chamber will act like it is missing, foul plugs, kickback and perform erratically, including acting like an electical issue. If it is an aftermarket cylinder, it will likely need two o-rings for the top and one to two base gaskets depending if you are running a spacer plate or not. Always perform a full Engine & Coolant Syatem leak down test to insure you have NO leaks.

Carlos.
 
#8 ·
Need to build a low pressure leak down tester or purchase one from your local source or eBay. Then, you leak down test the engine crankcase-cylinder-head and separately you leak down test the engine coolany system from water Pump through cylinder-head.

Search for more information on 'leak down testers"...

Carlos.
 
#9 ·
dumb question
is this on a stock cylinder? because if its a prox than doesn't the lower bolts thread into the water jacket area and if it leaks out of the bolt holes than you may be OK if ya just used silicone in the bolt hole

it confusing when you say it leaked after removing bolts on the orig flange and it leaked from one of the holes, its impossible to leak from a factory cylinders flange bolt hole.
 
#10 ·
Actually none of these aftermarket cylinders should have the exhaust flange threaded holes deep enough to break into the water jackets. If they do, they have been drilled too deep. As suggested the use of Silicone or a good Sealent like Three-Bond or a Threaded Plug and Sealant usually solves the problem.

Agreed; it would be a first to see an OEM cylinder leaking Coolant from the Threaded Flange Holes...

Carlos.