Club 80-90 Forums

Ok I had the van motted and the tick over is not right now.
I think the motter lads may have dabbled a bit

idle valve works
choke op looks good

this is what's happening... on a working temp engine
Setting the van to run on petrol @ 900 rpm no problem ticks over a treat
switch over to gas and rpm rises to 20,000

turn out the idle speed screw on the carb to reduce the rpm
tickover great.

Ah ha, I here you say.
adjust the gas on the vaporiser

Well, I do that and it runs crap when cold, won't start very well and misfires. Once warm it's OK

the emissions checks out on the gas and am getting a healthy 18 - 23 mpg
(CO 2%, HC 400ppm, O2 1%, Lambda 1.2)

Sure I've got this wrong, but, if you turn the sprung vaporiser screw in, this affects CO (mixture?) and weakens the gas mix?
Do you then have to compensate with the power valves by turning them out?

I don't want to bother Steve with this if I can do it myself.. but if I need him to take a look... I'll book it in.

Mmmm

Normally what happens is the petrol idle is higher and the lpg lower...

is there an air leak somewhere on the LPG fittings? I'd have though that thats the only way it could go higher... (need to think about this)

I'd be asking why they frelled about with it and what they did... maybe they have turned the lpg down a bit.. try and open the idle bleed screw a quarter or half a turn and see what it does..

you may need to close the "power valve" a fraction after mind..

Prob a good idea to speak with Steve though..

kevtherev wrote:switch over to gas and rpm rises to 20,000

That's a little high I'd say!

Talk to the man .... accept no imitations.

As Ian says..I talked to his Gasness Steve ..
after a proper cleaned up cruddy carb and a replacement choke flap Steve discovered a mixture screw wound all the way in.

All sorted now , well worth the trip.

Thanks steve.