Club 80-90 Forums

Thanks for sorting that . Could it be the carb-could that account for the rev increase when fitting the vacuum? Are the same carbs fitted to autos, I had a refurbished carb fitted last autumn

Same carb as well.
The idle speed will increase are you resetting it to 900rpm when you recheck the timing again?

So far I've been setting it a 5-7 btdc at idle without the vac on. When I attach the vac it shoots up to 30 odd and that's as far as I've got. Vac advance and mechanical advance working and the hole under the throttle butterfly is clear. If I try to adjust the timing downwards it stalls as soon as I take the vac off. Am I doing it right? I've got a rev counter now that clips on so I'll be able to be more accurate on the rpm now.

You need to reset the idle to 900rpm after you have fitted the vac pipe then check the advance.

is there a twin spigot vac unit on your distributor?

Hi Bigherb do i reset to 900 with the mix or distributor and kevtherev there's only one lever from the vacuum unit,

flyinghitop wrote:Hi Bigherb do i reset to 900 with the mix or distributor unit,

The idle speed screw (A)

I'm making a meal of this but just want to get it right.

1. set timing at 7 BTDC with vacuum off
2. Connect vacuum and set revs at 900 with idle screw

flyinghitop wrote:I'm making a meal of this but just want to get it right.

1. set timing at 7 BTDC with vacuum off
2. Connect vacuum and set revs at 900 with idle screw

Yes, not sure why you are doing it at 7 deg, it should be 5 deg BTDC

bigherb wrote:

flyinghitop wrote:I'm making a meal of this but just want to get it right.

1. set timing at 7 BTDC with vacuum off
2. Connect vacuum and set revs at 900 with idle screw

Yes, not sure why you are doing it at 7 deg, it should be 5 deg BTDC

Id guess because of lpg some people reccomend 8 degrees

Dizzy and vac unit look fine to me

When I get a chance I will do the test on mine and see what happens with the vac connected, it looks a new vac unit so is it the right one did you fit it?

It's what was on when I got it a couple of years ago, it'll be interesting to know what yours does. The tachometer I had seems to be faulty, intermittent and sticks a 500rpm so I'll have to get a new one.

itchyfeet wrote:
Id guess because of lpg some people reccomend 8 degrees

Mine is at 12 deg advance (LPG, 2.1DJ) 18 deg would be ideal but it would struggle on petrol.
stick to 5 for now.

12 degrees advance, vacuum off? I really want to go away at the weekend. So i'll set it up like that.

flyinghitop wrote:12 degrees advance, vacuum off? I really want to go away at the weekend. So i'll set it up like that.

mines a high compression 2.1 mate... stick to 5 deg

I'm LPGd as well does that change anything and back on the timing when the vacuum advance pipe is off should I have been plugging the end of it ?