Runing rich?

Post by **alex_holden** » Mon Jul 13, 2009 10:45 am

From memory, it took about 11 minutes to fill a 5 l can, so roughly 5.5 gallons per hour. There was a constant flow of air bubbles coming through with the fuel. I'd say it's something to investigate when you have a chance but probably not what's causing it to run rich.

Post by **bmcecosse** » Mon Jul 13, 2009 11:50 am

Alex - was the delivery pipe under the surface ? If not - it would very probably 'suck back' a little bit of air on each stroke until the valves swapped over and it could suck from the tank.

Post by **8009STEVE** » Mon Jul 13, 2009 12:02 pm

Alex - was the delivery pipe under the surface ? If not - it would very probably 'suck back' a little bit of air on each stroke until the valves swapped over and it could suck from the tank.

How do you think we saw the air bubbles in the fuel?

Post by **ani** » Mon Jul 13, 2009 12:20 pm

BMC - thanks for the explanation about the bridge - I will check this after lunch

Post by **bmcecosse** » Mon Jul 13, 2009 12:27 pm

Steve - there may well be bubbles in the fuel - they could be air - they could be fuel vapour. If air - where's it coming from ?

Post by **8009STEVE** » Mon Jul 13, 2009 12:34 pm

I don't know. I was trying to help. I wish i have never gone to the National! Why don't you look for the leak?

Post by **alex_holden** » Mon Jul 13, 2009 12:55 pm

bmcecosse wrote:Alex - was the delivery pipe under the surface ?

Yes.

IME you don't normally get a constant stream of bubbles coming through with the fuel when you do a flow test.

Air could be being drawn in through either of the the joints in the fuel pump between the inlet chamber and the diaphragm, the filter seal, or the fittings on either end of the inlet pipe. I had a look around and couldn't find any obvious fuel leakage from any of the joints, though it might only be a very slight leak.

As I said before, I doubt this problem has anything to do with why the engine is running rich.

Post by **ani** » Mon Jul 13, 2009 12:56 pm

Come on Steve - don't loose your sense of humour:D You did help, you know you did, and if you hadn't found all that muck in the carb I would probably have abandoned it on the way home. With your help and Alex completely re-building the pump for me - I went home completely awestruck at how fantastic people are when you're in trouble. Going back to the original question which was about running rich I think this has found it's way back to the fuel pipe. Everyone is only trying to help and as always I am truly grateful to everyone. I'm not exactly a mechanic but if I can help anyone out in any way on this forum I would be the first to offer.

Post by **bmcecosse** » Mon Jul 13, 2009 2:21 pm

Obviously - if the car was anywhere near me - I would look for it - but it's all got nothing to do with the original problem - car starting without any choke. So lets see what transpires! We all do our best to help others - it's not a matter of scoring points or telling others how to 'suck eggs' - which sounds a particularly gruesome sport - especially for a vegan - like me!

Post by **8009STEVE** » Mon Jul 13, 2009 4:22 pm

but it's all got nothing to do with the original problem - car starting without any choke.

So why worry about air bubbles!

Post by **ani** » Mon Jul 13, 2009 4:58 pm

8009STEVE wrote:When we did the work at the national, we told you that we had found the pump to be sucking a bit of air.

Steve,

Think it just came from your quote above nearer the beginning of the thread which then took the thought away from the mixture. Just a mis-understanding. Best to sort out the running rich problem and once that's done I can find out where this leak might be.

It's so easy to go off topic - most of the time is ends up being mildly amusing.

Post by **LouiseM** » Mon Jul 13, 2009 5:50 pm

Yes - let's get back on track. There's no need for anyone to get aerated.

Post by **ani** » Tue Jul 14, 2009 12:36 pm

Good news! Took bell off and checked to see if too much fuel was coming through - that was all good

Went out for a drive and then checked plugs - they had changed from their nice beige colour to very sooty black

(perhaps I should have checked this first as Dan said) Got mixture adjusted and then the idle. Drove back home - only a couple of miles and already the soot is starting to burn off. Just out of interest how long should it take for the plugs to get back to normal?
Thanks to everyone - learning new things every day

Post by **alex_holden** » Tue Jul 14, 2009 12:54 pm

Hurrah! Well done!

(Personally I brush the soot off with a soft brass brush before putting them back in)

Post by **dalebrignall** » Tue Jul 14, 2009 12:54 pm

not that long ive been fiddling with mine i think i have got it right,a decent run of about 10 miles will tell you.i was trying to set it up as the manual and wished i haddent ended up far too rich.the trip to the lakes will tell me.

Post by **ani** » Tue Jul 14, 2009 12:57 pm

Certainly should do - bit more than 10 miles

Post by **ani** » Tue Jul 14, 2009 12:58 pm

alex_holden wrote:Hurrah! Well done!

(Personally I brush the soot off with a soft brass brush before putting them back in)

Thanks Alex - I'll get one - there seem to be a number of uses for this little oft brass brush.

Post by **cormorant** » Tue Jul 14, 2009 8:50 pm

They are all gradually coming round to the idea of a little soft brass brush

Post by **alex_holden** » Tue Jul 14, 2009 9:49 pm

cormorant wrote:They are all gradually coming round to the idea of a little soft brass brush

I also have a big soft brass brush. Comes in handy for cleaning brass items!

I think it was actually intended for cleaning suede shoes so if you have trouble finding one, try a shoe shop.

Post by **bmcecosse** » Tue Jul 14, 2009 11:14 pm

Should be no need to clean the plugs - unless very oily - in which case probably better with new ones. How I was scoffed at for suggesting the soft brass brush! And now it's suddenly quite popular!
I would just give the car a good hard run ani - that will settle the plugs nicely. But - I have to ask - how did it get to be set in this seemingly highly rich running condition ? The best way to set idle mix is by using the little 'lift' pin on the carb. Ignore the manual - and its' two turns down and three up or whatever that says - it's really just NOT possible to set any kind of fixed guide like that - every engine is different! But do note that setting the idle mix does not guarantee the correct running mix - which is what will colour up the plugs. Although with a standard engine in fair condition - it should certainly be very close.