Rolls-Royce and Bentley Forums banner

21 - 40 of 54 Posts

·
Registered
Joined
·
47 Posts
Discussion Starter · #22 ·
Just an update I tried TuneIng the cabs as best as I can still has a slight shake at idle tried to check manifold gasket that looks alright sprayed some more brake cleaner around it the revs never changed it shakes at idle and also when it drops back down from 1000 to 600 revs
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #23 ·
Hello just an update try to tune the cabs as best as I can but shake is still there at idle
It also shakes when it's down reving from 1200 to 600
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #26 ·
Hi update here I’ve changed The manifold gaskets and rebuilt the carbs and engine is still shaking I’m lost now I’m thinking it might me a worn cam shaft
 

·
Registered
Joined
·
2,937 Posts
A video would help. It could be motor mounts(3) check the front mount.
 

·
Registered
Joined
·
485 Posts
An erratic timing mark indicates a worn distributor, and or sticky advance weights or anything in the ignition that would effect the timing light not to read the spark properly.
The pickup on the timing light is usually on number 1, check the plug and lead wire for that cylinder.
When was the last time the ignition wires were replaced ?
Old worn wires break down over time and can cross fire and you get a partial spark jumping to ground, this can also cause your rough idle and the timing mark to be very erratic when using a timing light.
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #32 ·
An erratic timing mark indicates a worn distributor, and or sticky advance weights or anything in the ignition that would effect the timing light not to read the spark properly.
The pickup on the timing light is usually on number 1, check the plug and lead wire for that cylinder.
When was the last time the ignition wires were replaced ?
Old worn wires break down over time and can cross fire and you get a partial spark jumping to ground, this can also cause your rough idle and the timing mark to be very erratic when using a timing light.
Hi update have change the spark plug wires and engine still shakes have timed it too and still no change the mystery is still there
 

·
Registered
Joined
·
485 Posts
Is the erratic timing mark still happening, and does the car have points or electronic ignition, and what type of electronic ignition, Opus Lucas or aftermarket ?

When I hear it running, it does not sound like a misfire to me, it would be shaking much worse then that and it would not rev strong like it does.
Still sounds like the spark is off a bit just to cause "not" a smooth idle.

And does it have the duel distributor set up ?

Also, remove the distributor cap(s) and rotor(s).
See if there is any side to side play in the distributor shaft(s), use quite a bit of pressure when testing.
Any side to side play shouldn't be there, even a tiny bit.

Please answer my questions. :)
 

·
Registered
Joined
·
2,937 Posts
A 1971 RR/B would have points and one dizzy .
 

·
Registered
Joined
·
485 Posts
Thanks Wraithman.
William, check the distributor shaft for wear, if worn, it needs to be sent off for rebuilding.
The "Distributor Doctor" comes to mind, after the rebuild he'll put it on a machine to check the dwell, advance curve and accuracy.
For now, check the points gap against the specs for your car, it may be too large.
When was the last time the points were replaced, assuming that you still have points.

And as before, if the timing light has not settled down, then the advance weights need to be looked at.
If they are not working properly due to week return springs and/or dirt, then the idle will never settle down.
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #36 ·
Thanks Wraithman.
William, check the distributor shaft for wear, if worn, it needs to be sent off for rebuilding.
The "Distributor Doctor" comes to mind, after the rebuild he'll put it on a machine to check the dwell, advance curve and accuracy.
For now, check the points gap against the specs for your car, it may be too large.
When was the last time the points were replaced, assuming that you still have points.

And as before, if the timing light has not settled down, then the advance weights need to be looked at.
If they are not working properly due to week return springs and/or dirt, then the idle will never settle down.
Hi thanks for getting back and for the help it has an aftermarket electric ignition it had points last year but still had the engine shake so I changed it to electric will check the distributor shaft tonight and get back to you thanks
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #38 ·
Thanks Wraithman.
William, check the distributor shaft for wear, if worn, it needs to be sent off for rebuilding.
The "Distributor Doctor" comes to mind, after the rebuild he'll put it on a machine to check the dwell, advance curve and accuracy.
For now, check the points gap against the specs for your car, it may be too large.
When was the last time the points were replaced, assuming that you still have points.

And as before, if the timing light has not settled down, then the advance weights need to be looked at.
If they are not working properly due to week return springs and/or dirt, then the idle will never settle down.
Hi check the weights and they look fine checked for play in the shaft there was about 2 mil play also used a colour tune and combustion spark is blue spark plugs look quite black tho only about a year old will put a video up of the exhaust mode keep popping Think it might be an unbalanced problem I took off one spark plug lead ate a time when running and they all made is run worst so it must be firing on all cylinders was looking at the cooling fan some other fins looked to be bent when I line them up to the top of the radiator some of them had a bigger gap than the other fins maybe the fan is bent and causing the engine to shake
Can this cause a problem like this

thanks
 
21 - 40 of 54 Posts
Top