SLROC Forum

Hi,

I have a v8 90 which was as a non-runner and got it running by putting some fuel in it, changing the sparks and battery, simple, so i thought!

Having an issue now with it idling very fast (2200 RPM) while also back firing quite often. I have a very limited mechanical knowledge, i'm guessing too much fuel? any suggestions where to start looking to sort this?

Cheers

Is it an auto or manual choke, if auto then is it perhaps stuck on?

If the choke is not stuck, check the ignition timing is spot on and also make sure their are no air leaks in the inlet manifold or carb (including the two vacuum outlets on the front of the carb - one is variable for the distributor advance/retard and the other is a 'constant' vacuum).   
If that is all checked, the only real possibility of running fast is to check and adjust the mixture and idle speed.  Try the idle speed first, it is (or was) the small screw passing through a coil spring on the external throttle linkage.   The mixture should be adjusted by turning the two mixture screws equally, in small stages and ideally with a reliable CO meter stuck in the exhaust pipe.

Thanks for the replies! it's a manual choke which I diconnected but i will try the other suggestions. Thanks for all the help!

Could be 2 things here, both largely addressed by Sandy M ...........
Fast idle caused by an air leak or unused pipe inlet not blanked off.
Backfiring ......... check and double check that the plug leads are in the right order (so easy to get wrong  )
Then disconnect any distributor vacuum leads and check the timing, it sounds retarded to me. These engines need bags of advance, up to 36 degrees, basically advance it until it pinks (not sure if it is drivable) and back it off the tiniest amount. if it has points they and the condenser may be faulty as well.

I'm assuming it all worked when it was parked up and that there are no nasty mechanical noises.

Good luck