Engine idling too high !

[hixsy]

rightyo ! stupid engine is now idling all over the place, its favourtie position is sitting pretty at 1800rpm, im finding it very hard to find the source as sometimes itll sit under 1000 and there seems to be no pattern to different idles it gets. i have no idea when itll rev higher or lower. the throttle cale aint stuck and idle screw is a no go as sometimes it will get below 1000rpm so cant be held by that?

any ideas guys and ill get the engine cover off yet again. . . .

DG 1.9 by the way

[CovKid]

vacuum pipe that has deteriorated or leaking? That'll certainly do it, as will any air leak on the inlet side.

[hixsy]

well can check, were would i start m8 ?

[CovKid]

Try the thin hose from the distributor vaccum unit that goes to the back of the carb for starters. Should be a snug fit - not loose either end.

[PEET]

And lube up the auto choke assembly assuming its a 1.9 carbed engine and wiggle it back n forth til its free as can be. Pop the air filter off n u can see it on the right hand side of the carb between the hoses and the carb main choke assembly - if air cooled see above... If its a diesel then I aint got a clue!

[HarryMann]

Yup, Fairly big airleak, you'll have to look at all the hoses off of carb and inlet manifolds, even inlet mani flanges/joints... run your closed hand up and down them see if idle changes (safety first, loose clothing etc), or if can't find it by detailed inspection (should be fairly obvious) then spray WD40 near to all the suspect areas, idle should change/increase/steady up.

[hixsy]

ok roger that then dudes ! ill check it out

thanks

[hixsy]

ok had a mess with the carb area today, used carb cleaner redex etc, one thing i did notice which im not sure is the flap inside carb is well open, is this normal? it seems the more i close the flap the more it settles to a decent idle speed, is the choke to the right? the thing between the carb and the throttle cable ? when i mess about with that it moves the flap inside the carb. it doesnt seem to return to any position just kinda stays where it lays so to speak. . . is that me problem ?

i WD'd the movin bits outside the carb and give em a good movin to make sure they aint stuck etc

[kevtherev]

busted spring in the bi metal housing
busted return springs on the choke mainshaft
choke pull down shagged

[hixsy]

ok after messing again with the carb/choke area ive sussed its the brass lever doesnt return to the bottom when i rev the engine, if i push it back down the engines idling nicely.

onto next question, is it just a spring needs replacing or is there more to it than that ? if so where can i get one, and wat extent do i need to goto replace it, am i to take the whole thing off or just a few bits?

thanks in advance

[kevtherev]

onto next question, is it just a spring needs replacing or is there more to it than that ?

no it's just a spring... now you need to be more specific and tell us which one has broke

[hixsy]

this is the lever im havin trouble with, i can see a spring on it, but cant tell if its broken ?

[kevtherev]

then you need to dismantle it.

Take off the carb and you'll be able to see the mechanism working much better
Disconnect the throttle cable and the wiring
take the pancake off
remove the Auto choke water pipes and petrol pipes

undo the three 10mm nuts and lift it off the studs

[hixsy]

gulp ...im scared.. is it simpler than it looks ? looks like theres a lot of pipes and stuff

[kevtherev]

OK then.. If it's too daunting then leave it to a mechanic... at least you can point to the prblem
the bi metal spring in that housing also controls the idle speed stepper. It needs to be checked for breakages too

there are three screws holding it together.. mark the position before you remove them