Tracing airleaks

[rosscla]

Any hints for tracing airleaks on a pig?

Mine will start and rev with choke warm or cold. Tick over runs away a gets very high before I have to kill it. All the symptoms of an airleak. Mixture screw makes little difference.

It's a Malossi 166, on an LML reed casing. Have had the head off, o-ring and gasket show no signs and head joint is dry. No sign of wetness around the head, exhaust or base gasket areas. no sign of leak or fuel around the carb box or casing.

Have tried 2 different carbs one 20, one 24, both have a similar result so I think its not the carb.

Ideas?

[bazman]

Looked at flywheel seal yet?

[mickymidas]

Flywheel & stator off to see if leak from F/wheel side seal .....or drop oil and sniff test for petrol in gear oil ?

[mickymidas]

Looked at flywheel seal yet?

Obviously great minds think alike ....

[rosscla]

Thanks, had discussed the possibility of the flywheel seal with my brother yesterday, will get the flywheel off this week and have a look. Cheers

[coaster]

Is there a possibility that the casings were opened a little too much? I'm told that there isn't much meat to play with and that it's easy to break through

[mick1]

Block the exhaust with cloth and hand(should cut out).....if it still runs it's sucking air in through the main seal...

[goldeneye]

to check for a loose/warped airbox, I spray a little WD40 between the box and casing while its running, if the revs drop, that's were ya leaks coming from. and did you put all the gaskets back between the reedvalve and the box /carb set up?

[rosscla]

@mick1 - you mean the drive side or the flywheel side? I always though a blown drive side seal mention oil p!$$ing out the breather like the Exxon Valdez?

@coaster. - it's a proper reed block case, we didn't open that any more, the hole’s big enough already...

@ goldeneye. - I'm sure It did but am gongt to strip it all off and check again anyway, one of the scenes that held the block down had to be retapped a bit, I'm wondering if it worked loose now... i'll try the wd 40 check first though, cheers. Won't be back at it till the end of the week now as it's in my brothers garage 70 miles away...

[goldeneye]

make sure the heads of the reed block screws are below the block, or the carb box will never sit flat. you may have to file a bit off the top of the screws, or maybe one has a burr on preventing the carb box sitting flat.