vacuum is from one of the carbs and have disconnected it . showing 30deg retarded at 2000rpmDarkspeed wrote:Whats the vacuum signal being picked up from? Are you checking the idle running with the vac disconnected?
Andrew
wierd timing
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the vacuum is coming from the n/s carb and it is working. have disconnected the vac pipe reved to 2000 rpm timing light on no.1 plug. the tdc mark on pully flashes between 8 and 9oclock on the crankshaft pully. at these readings the engine runs at its best.turn the engine off and check the tdc mark on the pully is in line with the pointer . the no 1 piston is at tdc and the valves are closed and the rotor is pointing at no7. if I alter the distributor and turn it so the rotor points to no1 it will not run until I retard it by 30deg.Darkspeed wrote:Whats the vacuum signal being picked up from? Are you checking the idle running with the vac disconnected?
Andrew
I have no idea what you mean by flashing between 8 and 9 oclock - If using a good light then you should see exactly what the timing is at any rpm.
Is that a typo or do you mean No 7 as that makes no sense at all if the dizzy is in the right place and all the plug leads placed accordingly.
I think you need to go back to timing basics - use the piston stop plug method to establish TDC is correct - remove the dizzy and re install in the correct position and then attach the leads and go from there.
Andrew
Is that a typo or do you mean No 7 as that makes no sense at all if the dizzy is in the right place and all the plug leads placed accordingly.
I think you need to go back to timing basics - use the piston stop plug method to establish TDC is correct - remove the dizzy and re install in the correct position and then attach the leads and go from there.
Andrew
4.5L V8 Ginetta G27
[quote="Darkspeed"]I have no idea what you mean by flashing between 8 and 9 oclock - If using a good light then you should see exactly what the timing is at any rpm.
Is that a typo or do you mean No 7 as that makes no sense at all if the dizzy is in the right place and all the plug leads placed accordingly.
I think you need to go back to timing basics - use the piston stop plug method to establish TDC is correct - remove the dizzy and re install in the correct position and then attach the leads and go from there.
Andrew[/quote
what I mean by 8 and 9.oclock is if you are looking at the crank pulley from the front of the engine and the top of the pulley is 12 0clock and the bottom is 6.oclock the timing light lights up the tdc chalk mark between what would be on a clock 8.30. going back to basic timing with the tdc mark facing the pointer turning the engine over with a bar and socket till the no1 piston comes to the top and that the valves are closed I take out the distributor and fit it so the rotor is pointing to the lead that goes to the no1 cylinder thats the one looking from the front of the engine it is the first plug on the right and is marked on the manifold as no1. after checking that all the things match up try to start the enging but will not start until I turn the distributor clockwise by two plug leads. then it runs ok . then with the engine stopped I turn the engine till the pointer is pointing to tdc.no1 piston is at dtc then take off the distributor cap the rotor is pointing to no7 cylinder as marked on the manifold. I know it does not make sense but that is what is happening. we have been to the south of France for several years running and no bother its just my timing marks show correct but his shows 30deg retarded?
Is that a typo or do you mean No 7 as that makes no sense at all if the dizzy is in the right place and all the plug leads placed accordingly.
I think you need to go back to timing basics - use the piston stop plug method to establish TDC is correct - remove the dizzy and re install in the correct position and then attach the leads and go from there.
Andrew[/quote
what I mean by 8 and 9.oclock is if you are looking at the crank pulley from the front of the engine and the top of the pulley is 12 0clock and the bottom is 6.oclock the timing light lights up the tdc chalk mark between what would be on a clock 8.30. going back to basic timing with the tdc mark facing the pointer turning the engine over with a bar and socket till the no1 piston comes to the top and that the valves are closed I take out the distributor and fit it so the rotor is pointing to the lead that goes to the no1 cylinder thats the one looking from the front of the engine it is the first plug on the right and is marked on the manifold as no1. after checking that all the things match up try to start the enging but will not start until I turn the distributor clockwise by two plug leads. then it runs ok . then with the engine stopped I turn the engine till the pointer is pointing to tdc.no1 piston is at dtc then take off the distributor cap the rotor is pointing to no7 cylinder as marked on the manifold. I know it does not make sense but that is what is happening. we have been to the south of France for several years running and no bother its just my timing marks show correct but his shows 30deg retarded?
It's all a bit weird as you said at the start.
My guess is that the crank pully damper (with TDC mark) is slipping on it's rubber mount.
It's probably slipping backwards when the engine is running and the pulley is loaded by the water pump and alternator and then it slips back again as the engine stops.
Just a possibility
Denis
My guess is that the crank pully damper (with TDC mark) is slipping on it's rubber mount.
It's probably slipping backwards when the engine is running and the pulley is loaded by the water pump and alternator and then it slips back again as the engine stops.
Just a possibility
Denis
1950 A40 Devon Hotrod with 5.0 twin turbo RV8.
EDIS8 wasted spark, Holley Injection.
Been as far as the Moon and back in 57 years of driving. Same Car, 5 engine upgrades !!!
EDIS8 wasted spark, Holley Injection.
Been as far as the Moon and back in 57 years of driving. Same Car, 5 engine upgrades !!!
I'm a bit late to this one.
I think the camchain has jumped (or been set incorrectly if it's been apart recently).
If the no1 piston is at TDC when the pointer says it is, then that much is correct, but just because at that time both of the valves are closed it doesn't mean that they are closed at the point that they should be relative to the crank, and when you get the engine running at its best with the timing miles out according to the pointer that's because it's working at the best compromise between the crank and camshaft positions. Lining up the rotor with no1 segment on the cap with the pointer on TDC means you're setting the dizzy correctly as far as the crank is concerned, but it's not positioned correctly relative to the camshaft, so to get it running at it's best the timing needs to be moved to a point where it's miles out according to the pointer.
I think the camchain has jumped (or been set incorrectly if it's been apart recently).
If the no1 piston is at TDC when the pointer says it is, then that much is correct, but just because at that time both of the valves are closed it doesn't mean that they are closed at the point that they should be relative to the crank, and when you get the engine running at its best with the timing miles out according to the pointer that's because it's working at the best compromise between the crank and camshaft positions. Lining up the rotor with no1 segment on the cap with the pointer on TDC means you're setting the dizzy correctly as far as the crank is concerned, but it's not positioned correctly relative to the camshaft, so to get it running at it's best the timing needs to be moved to a point where it's miles out according to the pointer.
In the OP it said it ran and pulled well at 30 degrees retarded.harvey wrote:I'm a bit late to this one.
I think the camchain has jumped (or been set incorrectly if it's been apart recently).
If the no1 piston is at TDC when the pointer says it is, then that much is correct, but just because at that time both of the valves are closed it doesn't mean that they are closed at the point that they should be relative to the crank, and when you get the engine running at its best with the timing miles out according to the pointer that's because it's working at the best compromise between the crank and camshaft positions. Lining up the rotor with no1 segment on the cap with the pointer on TDC means you're setting the dizzy correctly as far as the crank is concerned, but it's not positioned correctly relative to the camshaft, so to get it running at it's best the timing needs to be moved to a point where it's miles out according to the pointer.
Would it do this if the cam was out in combination with such a late ignition timing
Cheers Denis
1950 A40 Devon Hotrod with 5.0 twin turbo RV8.
EDIS8 wasted spark, Holley Injection.
Been as far as the Moon and back in 57 years of driving. Same Car, 5 engine upgrades !!!
EDIS8 wasted spark, Holley Injection.
Been as far as the Moon and back in 57 years of driving. Same Car, 5 engine upgrades !!!
I had one exactly the same, it would only run reasonably with the dizzy wound round clockwise until the vac unit hit the inlet manifold, so that was well retarded. Advancing it up just made it run dreadfully. I think the problem is that although the OP says it pulls well when it's that far retarded, it's in a trike, so it's not having to pull the same weight as it would in a car, or, as in the case of the one I did, a P5B. Even though it's retarded as far as the crank is concerned, it's working at it's best in relation to the camshaft.DEVONMAN wrote:
In the OP it said it ran and pulled well at 30 degrees retarded.
Would it do this if the cam was out in combination with such a late ignition timing
Cheers Denis
At the end of the day I'm only speculating just like everyone else, the only difference being I've encountered the symptoms before, and identified the cause, and we're only going to find out if I'm correct in this instance as well if the OP gets it in bits and tells what he finds.
