Electronic Ignition
- Thread starter georgecook
- Start date
georgecook
Member
After removing the head, the condition of the valves appeared fine. I turned the camshaft over a few times whilst on the bench and still fitted to the head. There didn't appear to be any sticking valves and things seemed OK. I re measured the clearances. One of the exhaust valves was a little tight, this I altered and refitted..
I agree with your comments it certainly to me in any case, sounds very much like a timing problem.
I have a cooling leak to fix on the heater box behind the head and will then carry out a timing check as follows, hoping that this invites comment..
Loosen the distributor slightly so that it can be turned by hand The vacuum pipe still attached
First I will start the engine (hopefully) on choke, am not sure what the revs will be , they could be anywhere.
Allow the engine to warm through, remove the choke and again hopefully the engine will settle at less than a thousand revs.
Attach the strobe to number one cylinder near the radiator
The pulley at the front of the engine has been marked with white paint at 6 degrees before TDC as has the pointer on the front housing.
Set up the timing as close as I can possibly get to 6BTDC and retighten the distributor.
I agree with your comments it certainly to me in any case, sounds very much like a timing problem.
I have a cooling leak to fix on the heater box behind the head and will then carry out a timing check as follows, hoping that this invites comment..
Loosen the distributor slightly so that it can be turned by hand The vacuum pipe still attached
First I will start the engine (hopefully) on choke, am not sure what the revs will be , they could be anywhere.
Allow the engine to warm through, remove the choke and again hopefully the engine will settle at less than a thousand revs.
Attach the strobe to number one cylinder near the radiator
The pulley at the front of the engine has been marked with white paint at 6 degrees before TDC as has the pointer on the front housing.
Set up the timing as close as I can possibly get to 6BTDC and retighten the distributor.
I mean the valve timing not the ignition timing. If I read correctly you cannot get the engine to run correctly with the ignition timing set to the book with two separate distributors. The valve timing could be out and its easy to check and dismiss this as the cause.
Open the inspection plate on the bell housing, drivers side. Remove the cam cover and turn the engine over by hand in a clockwise direction, with a socket on the crank pulley. Turn until No1 exhaust lobe ( 2nd lobe from the front ) is pointing down, valve fully open. You should see some markings on the flywheel 104 | EP | 108. through the inspection hole. Turn the engine over again to the same position, slowly as the markings come round until the 104 | line is aligned with the pointer inside the inspection hole. The marker is on the far right. Only turn the engine in the clockwise direction, if you go too far go round again. At this point the notch at the back of the cam pulley should align with the cam lock.
Open the inspection plate on the bell housing, drivers side. Remove the cam cover and turn the engine over by hand in a clockwise direction, with a socket on the crank pulley. Turn until No1 exhaust lobe ( 2nd lobe from the front ) is pointing down, valve fully open. You should see some markings on the flywheel 104 | EP | 108. through the inspection hole. Turn the engine over again to the same position, slowly as the markings come round until the 104 | line is aligned with the pointer inside the inspection hole. The marker is on the far right. Only turn the engine in the clockwise direction, if you go too far go round again. At this point the notch at the back of the cam pulley should align with the cam lock.
georgecook
Member
Pat... I went into the garage before I read your last post
What I did do, was to remove the cam cover and check to see whether the hole in the flywheel lined up with the camshaft notch position . This was done with the second valve from the front fully open. Everything appeared to be spot on.. I use an Allen key in the hole in the flywheel.
I then turned the engine with a screwdriver in number I cylinder plug hole to ensure it was coming to compression with both valves closed. With the 6btdc marks on the pulley lined up I removed the distributor cap to check on the position of the rotor arm .It looked to me as though the rotor was just leaving the number one cylinder contact position in the distributor cap. I was concerned about that but decided to see what would happen when tried to start the engine.
I replaced the cam shaft cover etc. and tried to start the engine. After perhaps three tries she burst into life on full choke at around 2000rpm.. After say a minute I removed the choke and hoped that it would settle into even running The revs dropped to about a thousand and then after say 30 seconds it cut out. I restarted the engine without choke using the accelerator and managed to get it to run at about 750 rpm , but very roughly
I fitted the strobe to number one plug and used the marks on the front pulley. It wasn't far out, perhaps 3 or 4 degrees.
Pat, re your post, will carry out a strobe check using the marks on the flywheel to see if there are any clues there
What I did do, was to remove the cam cover and check to see whether the hole in the flywheel lined up with the camshaft notch position . This was done with the second valve from the front fully open. Everything appeared to be spot on.. I use an Allen key in the hole in the flywheel.
I then turned the engine with a screwdriver in number I cylinder plug hole to ensure it was coming to compression with both valves closed. With the 6btdc marks on the pulley lined up I removed the distributor cap to check on the position of the rotor arm .It looked to me as though the rotor was just leaving the number one cylinder contact position in the distributor cap. I was concerned about that but decided to see what would happen when tried to start the engine.
I replaced the cam shaft cover etc. and tried to start the engine. After perhaps three tries she burst into life on full choke at around 2000rpm.. After say a minute I removed the choke and hoped that it would settle into even running The revs dropped to about a thousand and then after say 30 seconds it cut out. I restarted the engine without choke using the accelerator and managed to get it to run at about 750 rpm , but very roughly
I fitted the strobe to number one plug and used the marks on the front pulley. It wasn't far out, perhaps 3 or 4 degrees.
Pat, re your post, will carry out a strobe check using the marks on the flywheel to see if there are any clues there
georgecook
Member
Am just having a cup of tea after having another engine check over... With the eng9ne in the EP position,(as indicated on the flywheel) Allen key pushed into the flywheel hole and the camshaft lined up in the keyway, everything looks fine. I then removed the Allen key and turned the engine so that the front pulley pointer is aligned with the 6btdc line. I then looked into the flywheel hole and there are no markers on the flywheel indicating its position. Surely the front pulley marking should always line up with the flywheel markers.
Since owning the car I have always used the front pulley markers for timing and never the flywheel..... What am I missing here?
Since owning the car I have always used the front pulley markers for timing and never the flywheel..... What am I missing here?
Hi George
You are confusing ignition timing with valve timing.
Valve timing is the relationship between the crankshaft position and the camshaft position. You can check this as I mentioned above. If the position of the camshaft has changed relative to the crankshaft the engine will run roughly. If the cylinder head has been removed the cam chain could have been refitted in the wrong position relative to the crankshaft. If the cam chain is loose the chain could jump on the sprocket also.
The ignition timing is the relationship between the distributor rotor arm and the crankshaft so you would use the front pulley and a strobe as you said.
however I did notice that you said you had used No1 plug lead for the strobe. You should be using No4 the rear most on this engine.
Pat
You are confusing ignition timing with valve timing.
Valve timing is the relationship between the crankshaft position and the camshaft position. You can check this as I mentioned above. If the position of the camshaft has changed relative to the crankshaft the engine will run roughly. If the cylinder head has been removed the cam chain could have been refitted in the wrong position relative to the crankshaft. If the cam chain is loose the chain could jump on the sprocket also.
The ignition timing is the relationship between the distributor rotor arm and the crankshaft so you would use the front pulley and a strobe as you said.
however I did notice that you said you had used No1 plug lead for the strobe. You should be using No4 the rear most on this engine.
Pat
georgecook
Member
With my trusty Allen key in the hole in the flywheel and the camshaft keyway inline and the second valve from the front fully open am assuming that the valve timing is ok
At this position the pointer for the flywheel indicates EP108 which I am assuming is 108 degrees before TDC. I couldn't find any other marks which I could use to set up number four plug surely it must be there somewhere. In any event provided I am doing it correctly it seems much easier to set up number 0ne plug at the front of the engine ( with the fan blades removed)
The good news is that the engine is probably running as well as it has since I bought the car OK it still idles roughly, the revs without choke at idle vary between 500 and a thousand The noise is a splashy, swishy banging puffy sound which disappears more or less as the revs rise
How do I check whether the vacuum advance is working or not?
At this position the pointer for the flywheel indicates EP108 which I am assuming is 108 degrees before TDC. I couldn't find any other marks which I could use to set up number four plug surely it must be there somewhere. In any event provided I am doing it correctly it seems much easier to set up number 0ne plug at the front of the engine ( with the fan blades removed)
The good news is that the engine is probably running as well as it has since I bought the car OK it still idles roughly, the revs without choke at idle vary between 500 and a thousand The noise is a splashy, swishy banging puffy sound which disappears more or less as the revs rise
How do I check whether the vacuum advance is working or not?
georgecook
Member
I ran the engine for around 15 minutes without refitting the heat deflector plate situated between the exhaust manifold and the inlet manifold. This has resulted in the melting of the nylon connector on the accelerator linkage..So I removed the carbs and manifold and made a rather neat replacement using a brass pipe fitting. I then replaced the carbs and now she won't start. I checked, and have a spark and drained the battery while trying to get her to kick into life, probably flooded.
Do you ever think that some cars with you and some don't?
Do you ever think that some cars with you and some don't?
georgecook
Member
For whatever reason the car would not run . The only thing which had changed was the carburettors, which I had to remove to repair the throttle linkage. I rechecked the ignition timing and the spark was good and true. The plugs were very wet.
A mate came round and after heating the plugs in the oven he toyed with the choked while I turned the engine over. Finally the engine burst into life and is running roughly but is running.
Am recharging the battery and will see what happens tomorrow ( Demetrius, prior to removing the carbs I carried out a strobe check and the ignition timing is spot on, but how do I check that the vacuum advance is working ok)
A mate came round and after heating the plugs in the oven he toyed with the choked while I turned the engine over. Finally the engine burst into life and is running roughly but is running.
Am recharging the battery and will see what happens tomorrow ( Demetrius, prior to removing the carbs I carried out a strobe check and the ignition timing is spot on, but how do I check that the vacuum advance is working ok)
Demetris
Well-Known Member
With a standard distributor you probably can rely on the front pulley or flywheel marks to get a decent run. The problem is that you are using a non standard distributor and you cannot guess what kind of timing curve it might have. So as Rich says, it pays off to experiment a little with the engine running, turning the distributor slowly clockwise or counterclockwise and see if it improves things. Or even change the settings of the distributor. I knew that these distributors were available for popular engines, like the A and B series ones, but it sounds a little strange to me that someone got into the trouble to create some curves for such a rare one-off engine design like the Rover 4 cyl.
You don't have to worry about the vaccuum advance. It only works when cruising with a light throttle, where it advances the timing a little to give better fuel economy. It doesn't have to do anything with the idle characteristics.
You don't have to worry about the vaccuum advance. It only works when cruising with a light throttle, where it advances the timing a little to give better fuel economy. It doesn't have to do anything with the idle characteristics.
georgecook
Member
Will hopefully give that a try today, however with it being Xmas eve the good lady may have other ideas.
As a matter of interest, with the engine fully warmed up, by turning the distributor, do I aim to increase the engine speed ( without touching the carbs ) and then backing off just a touch
As a matter of interest, with the engine fully warmed up, by turning the distributor, do I aim to increase the engine speed ( without touching the carbs ) and then backing off just a touch
georgecook
Member
Renewed the choke cable and recharged the battery The car is turning over slowly but eventually burst into life on three quarter choke I turned the distributor both ways a small amount and have left it in the position in which I felt a small increase in revs. With some trepidation I then reversed out of the garage and took the car on a small run of about two miles. Its still noisy and the exhaust is puffy but there seems to be adequate power, and in all honesty I am over the moon
Unless anything unforeseen happens and no doubt it will I intend leaving the engine as is, for a while and try and build some confidence in its reliability.
Thanks fellas
Unless anything unforeseen happens and no doubt it will I intend leaving the engine as is, for a while and try and build some confidence in its reliability.
Thanks fellas
if it's driving better you should be able to sort noisiness etc