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It's running rich, the spark plugs show it and there shouldn't be all that black soot around the exhaust.
Clean the plugs up and lean out the mixture _ a little.
The plugs will look like that if you do short runs, not allowing the engine to get fully warm.
Short runs also don't allow the choke to shut off.
 

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Discussion Starter · #42 ·
It's running rich, the spark plugs show it and there shouldn't be all that black soot around the exhaust.
Clean the plugs up and lean out the mixture _ a little.
The plugs will look like that if you do short runs, not allowing the engine to get fully warm.
Short runs also don't allow the choke to shut off.
Hi I did lean it out and use the colour tune kit to get the right mixture but made no difference and there still popping the only time it’s not popping is when the choke is on I’ve all so tried to tune it 30 times now but still makes no difference I do the dash pot lift pin test to see if the mixture is all right and it’s seams not to work for some reason I turn the jets 2 turns down for a base line test and the car won’t even start I have to do about 4 turns for it to even start
 

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If you have to turn the choke on to get it to run with out popping, then it is too lean, but you have a vacuum leak somewhere, that's what it looks like at this point.
If lifting the dash pot piston pin yields no difference, then that indicates it's too lean.
You want a slight rise in rpm's and then a level off, as Jim says.
Also, if lifting the dash pot pin still yields no difference to matter where the mixture is adjusted, then that would indicate a vacuum leak.

In post 28 you said "the timing mark is erratic", then you said in post 32, "you timed it again", is it still erratic ?
The erratic timing mark has to be dealt with if it's still there.
The 2 mm play shouldn't be there either, but since you're running an electronic ignition, it shouldn't matter anyway, but still.
If this was my car, I would send the distributor away, and make sure that it's doing what it's supposed to do, to take that off the table.

The plugs are fouled, maybe a little oil is getting past the guides, but still looks like fowling from an overly rich mixture.

A vacuum leak leans things out, so you have to compensate by making the mixture too rich.
A vacuum leak is atmosphere entering the combustion chamber that isn't picking up any fuel through the venturi of the carburetor, so too much atmosphere and not enough fuel.
You can compensate for this by running the choke and enrichening the mixture, but the problem with that is now the extra fuel to compensate for the vacuum leak is running through the venturi _ too much fuel and fouling plugs.
It would also seem that you have to have an overly rich mixture as well.
It's not a large leak, so difficult to find, it's only effecting the idle, so it would seem.
Have you been disconnecting the weakener system through all this ?

The fowled plugs are also adding to the smooth idle problem.
Clean the plugs, and re-gap them, although the one shown looks OK.

One can only do so much on a forum, eventually one has to be there to see something that was missed.
 

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That plug is oil fouled, I would suggest you put in a set of Iridium fine wire electrode spark plugs. If it was running too rich the plug would show a dry fluffy black coating not shiny black like oil fouled. I'm not saying it's 100% oil fouled, it may also be too rich so that could be adding to the misfiring. Check your speed control bellows, it is a common source of vacuum leaks. The best way to check for vacuum leaks is to do a smoke test with a smoke generator. If the timing mark is erratic then you have some wear in a timing component. Put several chalk marks on the crankshaft damper then use the timing light on every plug lead to see if the firing is erratic on every cylinder. If the distributor bush is very worn then some marks should be more erratic than others. Did you mean 2mm or .002 thou distributor shaft play? .002 thou is nothing but 2mm is extreme and very likely the source of your misfiring.
 

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Discussion Starter · #45 ·
If you have to turn the choke on to get it to run with out popping, then it is too lean, but you have a vacuum leak somewhere, that's what it looks like at this point.
If lifting the dash pot piston pin yields no difference, then that indicates it's too lean.
You want a slight rise in rpm's and then a level off, as Jim says.
Also, if lifting the dash pot pin still yields no difference to matter where the mixture is adjusted, then that would indicate a vacuum leak.

In post 28 you said "the timing mark is erratic", then you said in post 32, "you timed it again", is it still erratic ?
The erratic timing mark has to be dealt with if it's still there.
The 2 mm play shouldn't be there either, but since you're running an electronic ignition, it shouldn't matter anyway, but still.
If this was my car, I would send the distributor away, and make sure that it's doing what it's supposed to do, to take that off the table.

The plugs are fouled, maybe a little oil is getting past the guides, but still looks like fowling from an overly rich mixture.

A vacuum leak leans things out, so you have to compensate by making the mixture too rich.
A vacuum leak is atmosphere entering the combustion chamber that isn't picking up any fuel through the venturi of the carburetor, so too much atmosphere and not enough fuel.
You can compensate for this by running the choke and enrichening the mixture, but the problem with that is now the extra fuel to compensate for the vacuum leak is running through the venturi _ too much fuel and fouling plugs.
It would also seem that you have to have an overly rich mixture as well.
It's not a large leak, so difficult to find, it's only effecting the idle, so it would seem.
Have you been disconnecting the weakener system through all this ?

The fowled plugs are also adding to the smooth idle problem.
Clean the plugs, and re-gap them, although the one shown looks OK.

One can only do so much on a forum, eventually one has to be there to see something that was missed.
Hey mate with the timing I re-time it to 10° At 600 rpm and it wasn’t erratic might just double check again Will check the time in at 1300 rpm to see if it’s at 24° and if it’s still erratic I have disconnected the weakness system when I rebuilt the carbs and put new inlet manifold gaskets trying to think with a vacuum leak would come from I’ve been spray and carb cleaner around all the inlet and carbs and nothing changes with the weakness system I did put it all back together but to be honest I don’t even think it even works any more thanks for everyone’s help
 

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Discussion Starter · #46 ·
That plug is oil fouled, I would suggest you put in a set of Iridium fine wire electrode spark plugs. If it was running too rich the plug would show a dry fluffy black coating not shiny black like oil fouled. I'm not saying it's 100% oil fouled, it may also be too rich so that could be adding to the misfiring. Check your speed control diaphragm, it is a common source of vacuum leaks. Pug off the vacuum hose going to it. The best way to check for vacuum leaks is to do a smoke test with a smoke generator. If the timing mark is erratic then you have some wear in a timing component. Put several chalk marks on the crankshaft damper then use the timing light on every plug lead to see if the firing is erratic on every cylinder. If the distributor bush is very worn then some marks should be more erratic than others. Did you mean 2mm or .002 thou distributor shaft play? .002 thou is nothing but 2mm is extreme and very likely the source of your misfiring.
Hi Jim

when I checked the distributor I took the rotor off and I could move the shaft underneath the rotor and it was about two mil movement as for the speed control diaphragm is this the cruise control as my car does not have one cheers
 

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Was the cruise control vacuum line/hose plugged at it's source?
 

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Discussion Starter · #50 ·
Hi here’s some photos I think this is a weakness device and the last photo was wondering where that hose comes off the float chamber go’s too and Photo number two wondering what that is to also been having dieselling when I turn off the engine
 

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I would become familiar with the workshop manual for your chassis #. It will show you where components are located.
BTW Your plug wires and hoses should be replaced and I suspect, based on what I see will help your issue.
 

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Discussion Starter · #52 ·
I would become familiar with the workshop manual for your chassis #. It will show you where components are located.
BTW Your plug wires and hoses should be replaced and I suspect, based on what I see will help your issue.
Hi thanks I have replace the plug wires will replace hoses cheers
 

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Discussion Starter · #53 ·
Hi dose my rolls have a anti-dieseling solenoid did the s1 cars have theses
 

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Use the factory workshop manuals or go to Flying Spares to see if that solenoid is listed for your year.
 
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