Gonna have a go at this. What PSI should I pump up the casinsg to?
Re: Leak down test
Posted: Fri May 30, 2014 4:21 pm
by coaster
dapper wrote:Gonna have a go at this. What PSI should I pump up the casinsg to?
Stop if you notice any bulging
Seriously, I used an electric pump and couldn't raise enough pressure to register on the dial. I filled a spray bottle up with soapy water and sprayed bubbles around each joint and seal. I initially had leakage from the exhaust gasket and then a small leak from the plug seat.
Re: Leak down test
Posted: Fri May 30, 2014 4:34 pm
by sean brady scooters
our kit recomends no more than 6 psi otherwise you run the risk of blowing the seals ,the important thing though is how long it holds the pressure ...
Re: Leak down test
Posted: Fri May 30, 2014 6:29 pm
by eden
its amazing just where air can leak from, a small water gauge is good to use once you think its holding at 6psi
Re: Leak down test
Posted: Fri May 30, 2014 11:45 pm
by sydduckett
sorry to hijack thread but was there a prev thread on how to do this yourself?
Ta
Sef
Re: Leak down test
Posted: Sat May 31, 2014 12:08 am
by coaster
Yes but it really is simple, cut a mountain bike inner tube leaving about 6" either side of the valve and fit one end over the exhaust stub with a big hose clip and the other end over the inlet manifold again using a hose clip. Then connect foot or electric air pump the valve and get pumping. I don't know how others that have used this method have faired but as the inner tube is fairly thin, I found that it inflated like a balloon rather than build up much pressure. I think the gauge on my pump only starts at 10 PSI but a generous application of soapy bubbles soon indicates any air leaks .
Re: Leak down test
Posted: Sat May 31, 2014 12:08 am
by rosscla
sydduckett wrote:sorry to hijack thread but was there a prev thread on how to do this yourself?
Ta
Sef
Was sadly on the other site Sef
Re: Leak down test
Posted: Sat May 31, 2014 11:59 am
by sydduckett
Ah, I see hence my inability to find it.. By application of bubbles I presume this means round all gaskets etc? Is it possible to do this thoroughly with the engine in the bike or would you need to remove it?
Ta
Re: Leak down test
Posted: Sat May 31, 2014 1:03 pm
by eden
ive just done a leak down test on my chaincase and found this..
Its my cast 240 engine that the chain broke in last year before the euro. it started leaking oil on this years modra rally, I thought it was leaking from the gear selector shaft, but its coming from loads of hairline cracks in the top of the case... full strip down needed
Re: Leak down test
Posted: Mon Jun 02, 2014 10:31 am
by paul213
tip for people wanting to bung up exhaust stubs for leak down tests. i use the mandrels out of cheap sanding drum sets if its just too small a bit of insulating tape does the trick
By application of bubbles I presume this means round all gaskets etc? Is it possible to do this thoroughly with the engine in the bike or would you need to remove it?