Has anyone got a link or ideas on how to test a Vespa Engine for an air leak, seen loads of info for Lambrettas but can't find much for a Vespa. I know I need to block off carb and exhaust but can't find how to do it.
Cheers bruce
Vespa air leak kit
if you have an old inner-tube cut a piece big enough to cover bottom of the carb cut holes for the studs re-fit carb tighten down that's how i did it
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For my vespa I think my exhaust stub pipe is not sealing tight against the cylinder. I sealed of the exhaust by clamping a rubber stopper in it. I took my carb off, cut a flat metal plate to seal the hole over the rotary pad, drilled a hole for a pipe through it, and cut a sheet of gasket for the bottom to seal it. I will test that area for air leaks, but when I pump I have zero air pressure and I have tested my pressure guage and bulb. I think air is coming out from where the exhaust meets the cylinder. I have been told that is a weak point of the vespa design, it doesnt make a good seal. What to do? Back the exhausts pipe out and try some gasket sealant on the threads and at the top?
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carpe scooter diem
1974 Rally 200
1965 Li150
1963 TV175
1974 Eibar Jet200
carpe scooter diem
1974 Rally 200
1965 Li150
1963 TV175
1974 Eibar Jet200
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Yes some high temp silicone sealant is what you need, re-fit and leave to set, then re-test, should fix your leakDavidsquaredson wrote:For my vespa I think my exhaust stub pipe is not sealing tight against the cylinder. I sealed of the exhaust by clamping a rubber stopper in it. I took my carb off, cut a flat metal plate to seal the hole over the rotary pad, drilled a hole for a pipe through it, and cut a sheet of gasket for the bottom to seal it. I will test that area for air leaks, but when I pump I have zero air pressure and I have tested my pressure guage and bulb. I think air is coming out from where the exhaust meets the cylinder. I have been told that is a weak point of the vespa design, it doesnt make a good seal. What to do? Back the exhausts pipe out and try some gasket sealant on the threads and at the top?
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- Posts: 225
- Joined: Sun Jun 10, 2012 11:41 am
- Main scooter: Early Eibar Jet 200
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Copper high temperature gasket on the threads, cut the fuel line down to minimum length to prevent air bubbles, and a new top end for the SI carb so needle and seat would close perfectly. After that problem solved. It was one or some combo of the above
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carpe scooter diem
1974 Rally 200
1965 Li150
1963 TV175
1974 Eibar Jet200
carpe scooter diem
1974 Rally 200
1965 Li150
1963 TV175
1974 Eibar Jet200