Topic: How to check for exhaust leak

[rachsrib]

I want to make sure I dont have a leak at the head. I cant feel any exhaust coming out but want to make sure Im not missing anything.  Can I put some oil or something in the cylinders that would cause it to smoke so I could see if the smoke is escaping anywhere?
Thanks

[Alan F.]

A few drops of oil down the spark plug holes should do the trick, maybe try one cylinder at a time.  

.....BUT if it was leaking you should be able to detect it without any special skills or equipment though.  If in doubt, simply remove your exhaust gaskets and replace them with new ones, they don't cost much and are still available.

[MCRider]

You can usually hear a leak as well. It'll often sound like a loose tappet with a sharp "tick" sound. Snugging up the afflicted port and the tick goes away.

Might be difficult to "make sure" beyond a shadow of a doubt. But for my money if you can't feel the little jet of exhaust you wouldhave with a leak, and you can't hear the tick, it doesn't leak.

[mystic_1]

Hold a lit lighter up to the pipe and look for disturbances in the flame.

mystic_1

[MCRider]

Hold a lit lighter up to the pipe and look for disturbances in the flame.

mystic_1

Great idea! One of those little smoke generators for finding air leaks in a house would work too. No idea where to get one. Puff a little smoke in the direction of the port and see what it does.

[tlbranth]

How about one of those incense sticks - Sandalwood. That'll bring the cops a-running.

[MCRider]

How about one of those incense sticks - Sandalwood. That'll bring the cops a-running.

 

[Philly550K1]

or these.

[hakon-cb750]

I have this ticking sound as well, when the engine is warm. I suspect my exhaust to be leaking. After 1 hour of riding, the lower part of my jeans are full of small dark spots from oil or something like that.    My bike (k7) is equipped with a Marshall D.T.-   

I am receiving new gaskets in the mail tomorrow - so now it's interesting to see if it works!

Can anyone tell me the torque in [Nm] the bolts must be tightened to?

[gane]

For 8mm studs, 1.6-2.2 NP. Be gentle w/exhaust studs. Any one who's broken or had one pulled from head can tell you how awkward repair is.Luck G

[MCRider]

I have this ticking sound as well, when the engine is warm. I suspect my exhaust to be leaking. After 1 hour of riding, the lower part of my jeans are full of small dark spots from oil or something like that.    My bike (k7) is equipped with a Marshall D.T.-  

I am receiving new gaskets in the mail tomorrow - so now it's interesting to see if it works!

Can anyone tell me the torque in [Nm] the bolts must be tightened to?

As Gane says there is a standard torque for 8mm studs, rule of thumb.

However, my rule of thumb, confirmed by others, when dealing with a set up with a crush washer, torque amounts don't really apply. You shold tighten till you feel the crush washer give, then a little more. Run it, if it leaks, tighten that one up a little more. Just enough is plenty, too much can be a heartache. 
That goes for exhaust, oil plugs, spark plugs, and the like.

BTW, I bot a Marshall DT for my project and have yet to use it. How do you like it?

[honda750k]

Common sense torque figures (aka snug then about1/8 turn more does the job for me)

Just be glad this isnt like Suzuki's dumdum idea on the GS500, katana and GSXRs with just a bolt rather than a stud going into the head, because those effing things ALWAYS break when ya try and take m out. its a bear to do.

[MoTo-BunnY]

Incense definitely works great to cover up yer pot smOke test for exhaust leaks - the wisps of thick smoke works better than just trying to blow smoke on it or something. It's an old trick to check on weather stripping sealing in your house, too.   

Also, with my exhaust leak, the bike would do small pops and backfires on rapid decel / letting off the throttle, as well as left some like smoke smudges on the engine fins nearest the leaking port.