probably aimed mainly at Mac and Pettaw but

HELLLLLLLLLLLLLLLLLLLLLLLLLP

havent used the redline since May started it up today and cant get the tickover to settle down it its running at about 1600 rpm when warmed up with the choke in ,

took air filter off checked all bolts were tight (do that as a matter of course now ) then tried screwing down the throttle stop screw so the throttle could close further , this worked for a while then the revs started building up again,

not really sure where to look next and dont want to make things worse ,

also noticed a there is a connector like the vacuum pipes go onto pointing toward the back of the engine bay that has nothing attatched , when I put my thumb over it the engine cut out , should there be anything attatched here and where do's it go ?

the block breather pipe go's to the airfilter and a spur go's from this to the carb base so I cant think where another pipe should go to if indeed one should be on there at all
any one got any pictures of where these pipes should go ?

any ideas guys

hmm difficult to tell without seeing it, but I think the hose is a red herring and its to do with the ventilation for the carb and so it should remain unblocked and unattached. If it was a vacuum pipe, you would more likely get better running when its blocked than with it unblocked.

Have you checked to see that the choke mechanism is 100% off? That can cause fast running like what you described. Set the cable with the engine hot as the thing expands and then you find the choke coming on when the underhood temperatures rise. That's particularly true on the Weber conversion for this model cos when I had a play with Chris's one just a tiny bit on the choke puts loads of throttle stop on.

Hi,

Not sure which pipe you're refering too - but an engine needs air to run - if you close the throttle plate it should get its air via the idle circuit - but that won't give you 1600 rpm! If a vac. or unrestricted breather pipe is 'open' to the manifold it will draw air there and you'll get a very high idle. (but closing it off should not necessarily stop the engine as the idle solenoid should still be open.

Quite plainly if you have 1600 rpm hot, with the throttle closed and no fast idle cam stuck on then the engine is getting excess air from somewhere - quite possibly via this open pipe connector.

First thing is to identify this - can you post a pic. ? How was your motor running before you 'laid it up' and what has happend in between?

Is your vac (econ) gauge still working - that will be supplied by a vac pipe to the manifold - possibly that? What size is this 'open' connector.

This is a problem that really needs someone actually looking under the bonnet - but is probably a fairly simple one.

More info needed - Mac.

whoops, i suspect everything would have been OK if you started by putting the loose vacuum hose back in place, instead of screwing at the carb...

now you first need to put it back where it belongs (ignition unit? recirc. system? ) and then screw up the idle speed screw again.


fair chance it'l run like always.

the wierd thing is there is no loose hose and I cant see anywhere a hose may have fallen off of that would have gone to this fitting , will try to get picks tomorrow

check the choke thing first

I dunno if it s the same problem, but my revs went mad once when the plastic bracket (or it might have been the spring) for teh accelerator cable snapped, so it was like the pedal was half down all the time.
maybe something similar happened. though i could be talking shite, i have very little idea what im doing when i poke around with my 340!

turned out to be a hole in the exhaust caysed the rough running so it was an air leak as Andy first said , thank god for our "experts "
(in joke with Andy lol)