Idle issues and more. Worth fixing?

[ac1176]

Don't squirt carby cleaner into the fast idle air valve itself. It can melt the wax pellet valve actuator and ruin the mechanism. The manual is actually quite explicit that all the byapss passages should be plugged when cleaning the throttle body to prevent cleaning fluid entering the bypass chambers. Doesn't even suggest that the throttle needs to come off the intake assembly to clean it.

Removing the speeder motor and cleaning its chambers is probably OK provided it dries fully before re-assemblng. Finding the right replacement gasket may be difficult these days, although you could probably make your own out of some gasket material using the old one as a template.

Careful when setting the idle speed with screws. There's two screws on the throttle - one opens a third bypass chamber around the butterfly valve, the other sets the butterfly valve stop position itself. The first one is the correct one to trim (plus other tweaks as detailed in the manual). The second one should be set with feeler gauges and shouldn't require adjusting from the factory.

[CCCMikey]

Thanks again for your advice

This is the screw I adjusted. I also rotated the TPS slightly to match the movement.

[ac1176]

Yep, that's the butterfly valve stop screw (note the white tamper-evidence paint on the threads). If you get to the bottom of your idling issues you'll have to reset it back to factory specs before you attempt to set the base idle again.

The idle speed adjust screw is recessed into the top of the throttle body under a small plastic cap...or at least it is in the V6.

[CCCMikey]

Understood

I've recorded the position so I can return it to normal. I knew that adding a little throttle would allow us to drive it until the issue is resolved. I could also understand that turning it the other way could do harm.



I think it might be in a different position on the 4 cylinder. I'll have another look on the weekend.



Found out some history on this vehicle. Last few years before I got it were short trips of about 5km.

[CCCMikey]

While adding a litre of motor oil (to make up for what has been burnt or escaped) I noticed that the water pump belt looked quite sick. Replaced it today.



There's also evidence of oil spray inside the cover and outside as well.

While doing the 5 minute burn-in of the belt, I could see oil leaking out of the cam shaft (I think that's what it's called). I guess that helped end this belt's life - or possibly the belt throwing chunks has given the shaft a rather hard time and added to the problem.



I'm guessing replacing cam shaft seals will be beyond my back yard expertise and should be given to a mechanic. Any old mechanic suitable? Or should I go to the one who advertises as specializing in engine rebuilds? There is a similar leak at the opposite end of the motor even though there's no shaft there - can see fresh oil dropping from a semi-circular plate, although I wouldn't be surprised if the entire rocker cover gasket was leaking too.