woobly carbs

[Phil]

cleaning my 1700 x/flow and replacing the cleaned K and N filters I found the carbs to be loos with a little movement between the carbs and the manifold, I believe this to be wrong and have tightened them up, but just to make sure can anyone help and tell me if I was correct in doing this. The other thing is my plugs are a little black in couler and I was wondering if this is caused by the carbs being loos and letting in air. I have only just got the car and have not delt with carbs in years. Thanks for any help given

 

 

[Blatman]

The carbs HAVE to be a little loose. Tight carbs will cause all sorts of fuelling problems. You should be aming for around 5-10mm of movement (I think. An archive search will reveal some info) at the end of the trumpets, depending on how long your trumpets are. IE, the longer the trumpet, the longer comparative movement should be.

If they are now very tight, it is possible that you have damaged the sealing between carbs and inlet (misabs?), so I would advise removal and replacement of the thackery washers and misabs. It's not a difficult job, just a bit tediuos.

NEVER tighten DCOE carbs so that they are solidly mounted.

[Phil]

thanks for your reply, very helpfull, well it looks like I have some more work to do, wish me luck.

 

 

[Nigel Riches]

If the plugs are black it would be an indication of to much fuel ie, running rich, could be clogged filters, K & N, not likely, wrong jets, on Webers, quite common, a good session on a rolling road should see you sorted, with better driveability and fuel economy, though with the x-flow fuel economy is not going to be good in comparison to modern injected systems, have fun and listen to the noises, smell those odours, feel those movements, drive it! ! !, Regards Nigel.

[Roger King]

Blatman's reply is precisely correct.

 

With regard to the plug colour, this is only of any relevance if you do a plug cut. This is where you dip the clutch and switch the engine off simultaneously. The colour you see on the plugs will then only apply to the conditions that you were running under (throttle postition, revs, etc) at the time of the cut.

 

If you look at the plugs after the engine has been idling, they will usually have blackened regardless of your jetting.

 

This doesn't mean that you are running rich, but unfortunately it also doesn't mean you aren't!