Advice on accessing a gunged up air fuel mix adjuster on SC

[Burma-Shave]

Hi guys, might as well post here rather than pelican, and support the cause.

Mike Bainbridge rebuilt my SC motor last year but I kept the CIS system to give it a clean, as it was all well mucky..obviously not well enough as when he went to do a post build tune up, he couldnt get the long allen into the adjuster for the air-fuel mix, said it was too crapped up. The car is running lean and needs adjusting.

Can someone advise the best way to get at it? The access hole is clear, just the adjuster head I think, seems deeply buried by the fuel distributor..Hopefully I am not going to have to remove the whole CIS gubbins?

[Brewster]

Actually removing the whole CIS isn't that difficult to be fair. Just be careful not to drop anything down the inlets when you lift the manifolds off. The mixture screw is a pig to get to. You could just split all the fuel lines to the distributor and take that off, but access might still be constrained.

The mixture screw is on the side and easy to get to. I thought it was the idle screw that needed the T-handled key.

[Jonny Hart]

If the head of the adjuster is gummed up, how about some carb cleaner squirted through a straw?

I think you might also be able to reach the adjuster enough to spray it by removing the air filter. It's basically just a screw that sits on the air meter plate arm.

Remember the adjuster is a long way down that hole. Even though I know exactly what to feel for now, there are times when it just doesn't play ball.

Also, never leave the allen key in. If the engine cools, you'll not be able to get it out and are in danger of bending the adjuster if you pull it too hard.

[Jonny Hart]

Just to add, when you do get to adjust it, the last move must be clockwise (richer). Movements are tiny, maybe 1mm at the end of the Allen key 'handle'. Rev the engine and leave the car to 'settle' for a good thirty seconds between adjustments.

[Burma-Shave]

Thanks guys, yes Brewster its other way round, the idle adjuster is under the heater blower, much easier to get to.
Thanks Jonny, I had wondered about squirting stuff in, will try that first, maybe see if I can get a sharp pick in there.
I had thought the engine needs dropped a little to get the CIS and manifolds off?

[Brewster]

I had thought the engine needs dropped a little to get the CIS and manifolds off?

I got mine out without lowering the engine. I didn't have a soundpad in there at the time. If it does need dropping it'll just be a case of supporting the engine on a jack and lowering the back an inch or two. Fingers crossed you can clear it out easily.

[sladey]

Partial engine drop no big deal - sounds worse than it is - just loosening screws effectively

(IIRC you already know that - not teaching you to suck eggs or anything)

It's usually better to get this stuff out to get at it properly rather than try and reach it

[jb]

How about getting an air line onto it?

[acclassics]

if you do go for a partial engine drop, disconnect the gear linkage coupling, so it dosent stress the shift rod/linkage, more a precaution.

even an 1/8th of a turn on the CO, can be 2 - 4% so just little by little.

Taking the air flow meter off/fuel distributor to get bench access to the screw you need to clean, is very easy, the most awkward bit is the rear fuel connections, other wise very easy to remove and do it on the bench, just mark your starting point, if you turn the mixture.