fuel vaporisation

p6 john said:
thanks what is the capacitor
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Sorry, bad habit of mine. on a car its called a condenser (in side distributor as 99.9% of people already know) but it is basically a capacitor just an old term for it. Cheep to swap out as well and a good first point to start.
 
yes i can hear the pump sometimes when the engine is running . i dont know if its the right pump for for car it looks different to the electric pumps i have seen on other p6 its quite noisy aswel
 
p6 john said:
thanks what is the capacitor
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It's part of the ignition also referred to in an ignition system as the Condenser. Read up about why a capacitor in an engine system is called a condenser. Interesting, they say it goes back to Watt and his steam engines.

I'll put my tuppence with Julian.
Julian said:
I still put my money on coil or capacitor
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Buy a cheap one, try it. If the cheap condenser fixes the problem, buy a good condenser as the modern cheap ones will soon fail. (carry a spare too)

In our case the vaporization usually raised its ugly head when restarting the engine soon after it was stopped when very warm. The vapour we assume stopped the fuel pump working, I assume that the vapour was in or near the standard engine driven pump.

But to answer your question:
Yes, it did happen to our car, we removed the mechanical fuel pump, replaced it with an electric pump in the boot.
 
My fuel pump is a Facet, mounted in the engine bay, and can be heard ticking when the ignition is first switched on, as the carbs fill. After that, in normal running it will 'tick; very slowly as it sends fuel to the carbs.
When vapourisation occurs, it will 'tick' frantically, at full speed, as it trues to pump vapour. Before Icured it for once and all, as noted above, thsi ticking was a warning of vapourisation starting..
NB. over fitted a return fuel line from Carbs to tank, to re-circulate fuel in an attempt to cure vapourisation. if this is still in place on your car, the fuel pump will run continuously, vapourisation or not. Re-circ. pipe runs from the RH carb float chamber back to the tank. It might have been blocked. off when the electric pump was fitted.
Dos your pump use the reserve feature? If so it might be an older Solex pump, perhaps fitted to P4's, and NLA. Facet pumps are single inlet and single outlet, more normally fitted in engine bay. Technically these are "Long suck, short blow" pumps. Pump near the fuel ank is a "short suck, long blow" pump.
 
hi the pump looks quite new it has one pipe going in and one pipe going to a transparent filter then to the carbs
 
p6 john said:
i; think my car has electronic ignition does it have a condenser
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If you have electronic ignition you won’t have a condenser. If you pop off the distributor cap you should be able to tell. Unless it’s an amplifier style with an external amp box. Those sometimes use the original points as the trigger.
 
hi it is electronic ignition , I finally got the plugs out after grinding down a plug socket like suggested , the plugs were black does that mean the carbs are running to rich and would that cause the spluttering and cutting out once the engines hot
 
p6 john said:
hi it is electronic ignition , I finally got the plugs out after grinding down a plug socket like suggested , the plugs were black does that mean the carbs are running to rich and would that cause the spluttering and cutting out once the engines hot
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If it’s very rich it could foul the plugs. Carbon on the plugs can also be a sign of poor ignition as well. What coil are you running?
 
Are you sure the plugs are the correct type? Rover changed the spec of the v8 plugs early on to avoid similar issues, if your car has later heads fitted these were of yet another spec. I'm sure somebody can advise the correct type.
 
Remove a rocker cover & check to see if it has original heads. If you're lucky it will have Sd1/Range Rover heads fitted (they breathe better & are a bolt-on improvement). The ID number is in the middle.
Original heads have short reach plugs, the later heads use long reach.

See post #65 here:

Recommissioning of the Denovo 3500

Bruiser's old heater. I didn't strip this completely, just removed the two front panels & the matrix for cleaning out. I back-flushed it then put some white vinegar in it for a couple of days before hosing it out again. Wire wheeled the casing then covered it in etch primer & Tough Black. It...
classicroverforum.net
 
If the plugs are correct type I use an old fashined tool called a Gunsons Flash test (an overpriced one on ebay at the moment) when the engine is running OK, this will tell you what the HT (spark) voltage is when the engine's behaving. Next time you have an issue do another test. You'll then know for certain if your problem is electrical or fuel related. I know easier said than done but the Flash test is really easy and safe to use - even I can use it!
Incidentally if you get hold of one don't ever lose sight of it i.e. lend it out, I've lost one through doing just that.
Steve
 

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thanks my dad had one of those no idea what happened to it , I have found a local mechanic who only works on classics , hopefully he will get to the bottom of the problem
 
hi I have just changed the coil for one of a donner car and drove round the block a few times then switched it off waited about ten minutes started it again drove around the block again without any problems , fingers crossed it sorted that problem out , I might buy a new one and keep the other as a spare . thanks for everyones help and advise
 
Hope it cures it for you, it's really good when folks remember to let everybody know when they find a solution. We have a small but enduring local meet for the Rover P6 Owners Club where this sort of issue gets thrashed about till we find a solution between us, having said that, we rarely speak much about P6s!
 
Have you resolved the problem yet ?
I am having the same problem,changed to a electric pump under the bonnet ,because I thought the mechanical wasnt up to it ,but no change .
I have read all the suggestions ,but cant understand why the coil or sparkplugs would affect the fuel supply.
my next option is to reroute the fuel line to come up by the bulkhead and along the inner wing to the coil which is where the electric pump is fitted ,thus avoiding running between the engine and exhaust manifold
 
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