two stroke dripping from my mag house joint??

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alcoholic maniacs sc
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not something ive come across before after 30 years of Lambo's. there a copious amount of two stroke with a petrolly wiff dripping from the mag housing to engine joint/gasket/area. it doesnt appear to be coming from above and its quite bad. the gasket was last replaced in 2008 ish. the GP2oo is now running a little lumpy on low revs and a tad hot. could this be the cause?. does this mean any of the oil seals have gone as well or could this be a simple relacement gasket job?. does unburn fuel find its way out of a knackered mag gasket? could a mag flange bolt have worked loose over time and be allowing the seal to deteriorate. will it make it 60 miles to Lincoln with a bit of silicon slopped on????? :roll:
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bristolmod
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probably the mag gasket- as you've got to strip anyway, I'd be inclined to change the flywheel side seals as a matter of course as well as the mag gasket.

Not burning any gearbox oil as well is it?

It could be something as simple as the carb flooding a tad and dribbling down though- suggest a spray of Gunk in that area to see where its coming from first.

Chris
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olliewtf
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i had the same, nipped up mag flange but problem persisted, turned out to be failed base gasket seeping down the casing to the bottom of the mag flange. it could just as well be your mag gasket, only suggesting you check base gasket too.
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alcoholic maniacs sc
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yeah, the scooter is running a tad lumpy so i reflatted the cylinder head thick alloy gasket and reflatted the cylinder head on 1200 grade and a mirror last week when i replaced a failed exhaust to cylinder gasket. i guess i should have replaced the base gasket as well while i was surgeoning. :-(
i've never had so many failed gaskets as in the last 10 years, they are probably using modern synthetic materials now, id be happy to track down some real 80's gaskets!. i might risk the scoot the 120 mile round trip to Lincoln and strip when i get back. so its either base or mag gasket , Lambrettas should have starred in groundhog day........ :cry:
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eden
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When doing leak down tests it's quite often the case that the motors leak from there. I use sealant and gasket.


I've seen many cases that have dents on the mag gasket face that line up with the seal plate screw heads. This is often coursed by numpties using impact drivers with out an extension bar on the driver to tighten or loosen the plate screws. A standard impact driver is just the right length for the Base of the handle to hit the gasket face if an extension isn't used.
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alcoholic maniacs sc
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when i rebuild the two halves i will use a new gasket and sealant, what are your thoughts on 2 gaskets?. i have never used an impact driver and the seal has lasted years. do you remember old asbestos based gaskets, they never just peeled off. you used to have to scape em off and rub down the surface with WD40!! they were twice the gasket of this current s**t. :idea:
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eden
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The ones I'm using are the old ones ;)
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wack 63
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I agree that the modern gaskets are crap compared to the old graphited ones, luckily I found a few OS ones a while ago but they're no good on modern kits. For that reason I always use gasket goo as well.
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The harry barlow green ones are great unlike the ones I got from well im sure you can guess .....
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wack 63
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Orange by any chance?
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