Engine start probs!?
Discussion
Hi all
Was wondering if anyone can shed some light on my new engine problem. The car starts normally from cold and runs and revs fine. After its warmed up i stop the engine. If i re start immediatley it is fine, however if i leave it for more than 5 minutes it will not re start! If you then leave it for 45 minutes it re starts and you are back to step 1.
I initially thought it may be heat soak from the exhuast manifold vapourising the fuel before it gets through the inlet (as the plugs dont seem to be wet) so i have bandaged the manifold and introduced a heat sheild between the exhaust and the inlet manifold.
It has not worked.
Any ideas?
Extra info:
Its a 1430cc with 45 DCOE weber.
Thank in advance
Ben
Was wondering if anyone can shed some light on my new engine problem. The car starts normally from cold and runs and revs fine. After its warmed up i stop the engine. If i re start immediatley it is fine, however if i leave it for more than 5 minutes it will not re start! If you then leave it for 45 minutes it re starts and you are back to step 1.
I initially thought it may be heat soak from the exhuast manifold vapourising the fuel before it gets through the inlet (as the plugs dont seem to be wet) so i have bandaged the manifold and introduced a heat sheild between the exhaust and the inlet manifold.
It has not worked.
Any ideas?
Extra info:
Its a 1430cc with 45 DCOE weber.
Thank in advance
Ben
Yep i like your thinking i thought along the same lines. It was a Facet solid state pump which pumped it along the standard mini metal fuel line. But thinking that this could be the trouble i have now upgraded the pump to a Facet red top with an 8mm line running through the car. It goes to a regulator, then to the Weber.
I have checked and the fuel is definatley getting through (running about 7psi on the gauge).
Are there any seals or parts of the Weber that could be doing this?
I have checked and the fuel is definatley getting through (running about 7psi on the gauge).
Are there any seals or parts of the Weber that could be doing this?
Actually the standard Facit is an excellent pump and my 1310 cc 'S', which must use a lot of fuel, runs well on just one, although I have two fitted for reliability. In fact, your fuel pressure sounds a bit high and I usually run about 4.0 psi. Maybe knock that back a bit.
I doubt that it's vapourisation as that's never really been a Mini problem, even with twin SU's and a big-bore manifold, unless in exceptional conditions like 35+ deg C and high revs at lowish speeds for long periods.
Just a few thoughts. Warm it up and get it to the point where it won't start. Then remove a plug and check for a spark. That will rule out the ignition circuits. I don't know what sort of dizzy you have, but check the advance is advancing properly. With a mechanical one it's easy, but with the electronic sort you probably need a scope or a meter.
If it's neither of these then it must be the fuel supply/mixture and you would probably need to go onto a rolling road to sort that out, assuming it's not something silly like a partially blocked jet. I'm not a Weber expert and whenever I've fitted one I've used nominal jets and had it set up on the rollers to make sure it's right.
If you have a manifold with twin SU's it might be worth swapping it just to check this out. I am assuming that you don't have a water-heated manifold. If you have, then by-pass it straight away.
"Won't start when hot" is usually a mixture problem.
Sorry I can't be more help. Let us all know what you resolve with this.
I doubt that it's vapourisation as that's never really been a Mini problem, even with twin SU's and a big-bore manifold, unless in exceptional conditions like 35+ deg C and high revs at lowish speeds for long periods.
Just a few thoughts. Warm it up and get it to the point where it won't start. Then remove a plug and check for a spark. That will rule out the ignition circuits. I don't know what sort of dizzy you have, but check the advance is advancing properly. With a mechanical one it's easy, but with the electronic sort you probably need a scope or a meter.
If it's neither of these then it must be the fuel supply/mixture and you would probably need to go onto a rolling road to sort that out, assuming it's not something silly like a partially blocked jet. I'm not a Weber expert and whenever I've fitted one I've used nominal jets and had it set up on the rollers to make sure it's right.
If you have a manifold with twin SU's it might be worth swapping it just to check this out. I am assuming that you don't have a water-heated manifold. If you have, then by-pass it straight away.
"Won't start when hot" is usually a mixture problem.
Sorry I can't be more help. Let us all know what you resolve with this.
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