Running Problem - Help Needed

[servetakid]

Made an air leak tester, and it looks like the mag housing gasket is leaking? The air is coming out of the stator plate blot holes... its like a wind tunnel out of one!! Also, there is some bubbling of fairy liquid on the outer flywheel side seal. Doesn't look in bad condition, but is this an indicator they should be renewed?

[fastfrog]

yes change it....

[Adam_Winstone]

Choke plunger not sealing correctly and allowing additional air into the system? This can be because of the choke cable being too tight or the wrong short plunger being used. I'm not saying this is the case but check it and tick it off the possible causes list.

To check for adjustment, make sure that only approx. half of the brass plunger is visible when looking down the hole that is to the side of the carb mouth. If it is only half uncovered when the choke is ON then you can be pretty sure that the choke if fully closed/seated when in the OFF position.

Best of luck.

Adam

[servetakid]

Hi Adam, that was one if my first thoughts. It see the above post about mag gasket and seals, I'm going to renew them all

[wack 63]

Interestingly I've found that even on good casings and mag housing faces air leaks occur ,so I use a sealant everytime now.I don't know if it is down to the quality or thickness of the gaskets nowadays as I seem to remember the old gaskets were always thicker and offered some crushability. For the outer flywheel seal to leak air ,then the large seal must have gone. I pressure test every motor I build now and even found new exhaust manifolds can leak on the factory welds.

[servetakid]

I've fitted a new mag housing, with fresh rolf seals and a thick MB gasket with a liberal dose of sealant. I then found in a pin prick hole in the welding i had done on my cases, so I've filled it with some JB weld. Now after pressure testing, I can see no evidence of a leak.

It was still reving high, all be it slightly better. So I fitted a AV266 atomiser and this helped. I took Adams advice about choke plunger, this also improved matter quite significantly. But still a little high on idle, so I then fitted a 60 pilot. It all seems alot better now. However, the choke does have minimul affect?

Jordan

[servetakid]

Can any one advise on the correct size choke jet? So I can check mine?

[wack 63]

Pretty sure they come with a 70 choke jet. Have you checked the exhaust manifold for leakage as the single wall stub doesn't seal too well?

[servetakid]

Yeah, checked the exhaust side, all seems well. It had a 50 in, so I have upped it to 60... Just working on the jetting now. Its lean at 1/4 - 1/3 throttle - 30mm PHBH, AV266, X13 second clip down and 128 main - NK Rally Road, Stage Four & 60mm Crank

Plug colour at lower revs

[vespanic]

I did a search on LCGB and got the info below. I didn't copy all I think but these were all very similar and helped me to check mine. All on stage 4 Indian barrel. Hope it all makes sense. With regard to your question on jetting I'll check tomorrow if I remember but may have been a typo and could have been 246. Good Luck

30mm PHBH through RamAir filter
choke jet 70
pilot 55
main 120
atomiser AV266
slide 40
needle X7 - clip in 2nd from top posn

53 idle,
av266,
x7 second clip from top ,
125 main
had a ram air filter on

AV266
X7 clip p2
pilot 55
Main 122
choke 70
float valve 300

av266 x7 125 main . 50 idle ram air

without
AV264 atomiser
128 main
40 slide
53 pilot


AV266, X7 (T2), 50 pilot, 40 slide, 60-70 choke jet, 122-130 main jet.... as a starting point and subject to testing.


70 choke
X7 on 2nd clip down
300 float needle.