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OP
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I was checking the timing on my '74 4/4 today and noticed that it seemed really advanced (like 20 degrees plus) at idle. Measured with my timing light. SO I decided to check the static timing and set the pulley timing mark to 8 degrees (not quite sure what it should be but got to be somewhere around there!). When I took the distributor cap off the points were fully open. When I set the points to just opening by adjusting the distributor body the engine wouldn't start! So I put the distributor body back to it's original position. Engine runs. I started to turn the distributor to retard the ignition but got to the point where the engine stalled so would need to adjust the idle speed. I've no experience of these carbs so left that to another day. The only thing I can think of is that the pulley is not marked correctly. Are they marked from the factory? The mark does look like it's been made with a cold chisel! I guess I'll have to check the TDC position but that involves degree wheels and dial gauges. It got me back from Bristol last week although I did think it pinked a bit. Left me a bit confused.
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Joined: Aug 2015
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Talk Morgan Enthusiast
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Talk Morgan Enthusiast
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Unlikely that the pulley has been marked up incorrectly, just my opinion.
I set my crossflows up at between 8/10 degrees btdc at 950 rpm, with the vacuum pipe disconnected. Seems to run well enough.
Did you check whether the bob weights in the distributor were free? I've had a few instances on where they have seized.
Arwyn
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Gone to Porsche Part of the Furniture
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Gone to Porsche Part of the Furniture
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X flows timing is easly checked from start to finish, Basics The notch in the front pully is like a chisel mark not to worry there, No1 spark plug out long thin screw driver down bore bring piston to top dead centre, rocker cover off see if No 1 Rockers are top dead and No4 is rocking, that will inform you timing chain hasnt slipped.
Distributor cap off, Rotor at number one points open you should have enough twist left and right on the Distributor body to get the ignition timing, now i can't remember if the Distributor is on a worm gear or a peg, with the extention on to the cam a worm, maybe the worm gear is 1 x tooth out if the point arm is well before or aft the Distributor cam loab i would be looking to see if the Distributor is miss aligned.
Last edited by Dean-Royal; 06/03/20 08:41 PM.
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Salty Sea Dog Member of the Inner Circle
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Salty Sea Dog Member of the Inner Circle
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Graham (G4FUJ)
Sold L44FOR 4/4 Giallo Fly '09 Gen2 MINI Cooper ragtop '90 LR 90 SW
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Talk Morgan Expert
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Talk Morgan Expert
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X flows timing is easly checked from start to finish, Basics The notch in the front pully is like a chisel mark not to worry there, No1 spark plug out long thin screw driver down bore bring piston to top dead centre, rocker cover off see if No 1 Rockers are top dead and No4 is rocking, that will inform you timing chain hasnt slipped. That was my first thought: one link slip on the timing chain is about 20 degrees.
1972 4/4 2 Seater
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OP
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The points had a very small "pip". I dressed the surfaces with a slip stone. I'll probably fit electronic points at some stage.
I'll double check TDC against the valve lift although it's pretty tough trying to rock the car in gear to get the engine moving. There's no room to turn it from the pulley bolt!
I'll also take off the distributor and strip that down. I'd not considered the weights sticking at max advance. I did have a Midget once that had a frozen distributor but that had no advance at all. The distributor has a skew gear drive not a peg.
Thanks for your suggestions!
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Joined: Aug 2015
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Talk Morgan Enthusiast
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Talk Morgan Enthusiast
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X flows timing is easly checked from start to finish, Basics The notch in the front pully is like a chisel mark not to worry there, No1 spark plug out long thin screw driver down bore bring piston to top dead centre, rocker cover off see if No 1 Rockers are top dead and No4 is rocking, that will inform you timing chain hasnt slipped. That was my first thought: one link slip on the timing chain is about 20 degrees. Pretty unlikely to be a slipped timing chain, given the OP has driven the car back from Bristol with no apparent problems!! In all the years I've built, used and abused Crossflow engines in all states of tune, I've never actually managed to get the timing chain to slip You should be able to turn the engine over on a spanner from underneath as it were! I've used the H&H electronic ignition kit for the Motorcraft 771 distributor, absolute doddle to fit. Can't really comment on performance improvement as I fitted it at the same time as a 5spd gearbox and new Weber DGV carb Arwyn
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Joined: Feb 2019
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OP
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Problem solved. As I said there is a mark in the pulley that lloks as if it was made with a chisel. This I thought was the timing mark. However there is another much less obvious mark (mostly filled with paint) that is the true timing mark. That is about 4cm away from the larger mark. Having stripped the distributor to check for weight mobility and reset the static timing everything appears ok. I have about 10 degrees at idle (800rpm or so) and peaking at 30 degrees. That is with the vacuum advance disconnected. It/s almost 40 degrees with the vacuum pipe on. I thought the vacuum advance was only active at low revs.
So I went out for a drive of three or four miles. Everything ok except that when I got back on to the drive the engine cut out and would not start again. It would catch but stop straight away. We had to push it back into the garage. A few minutes later it started ok. Very strange. Vapour lock? Non vented fuel filler? It was ok for our long trip last week. Oh the joys of old cars!!
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Part of the Furniture
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Part of the Furniture
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Arwyn`s wise suggestions re confirming timing marks by feeling for TDC through the plug hole reminded me of my early years of working on my old m/cycle engines, where the method of timing involved measuring the height of the piston relative to TDC through the plug hole and setting the Mag using a bit of fag paper from a roll-up to detect when the points were about to open.... Of course technology moved with the times when it was no longer thought acceptable to double the thickness of the cardboard on a fag packet to determine a the plug gap, when we could now afford to buy and use feeler gauges for such tasks.. In time we even got into high tec in setting the timing on cars by lining up the timing marks, ign switched on, and using a transistor radio just off station with the volume up, to then slowly turn the dizzy until the radio crackled to inform us the points had just broken... Job done.. (-: Just as well technology moves on given few folk smoke these days thus the old timers (no pun intended) would have been stuck looking for feeler gauge substitutes.. (-:
Dug out my old Haynes Ford Cortina76-82 1593 -1993 CC manual that suggests 6 deg BTDC for the 1600, and 8 deg for the Ghia which I suspect is down to a possible difference in compression ratio, though as with all Morgans of a certain age, who knows how heavily they may have been breathed on over the years making standard engine settings somewhat inappropriate today..? Of course changes in fuel makeup can also complicate perfecting ign timing older machinery these days too..
I note you have checked that the dizzy advance system is operational, I ever check the initial operation of the springs and bob weights by twisting the rotor arm and watching it spring back to confirm the outer shaft on which the points lobes are mounted is free to rotate on the inner shaft that is directly connected to the camshaft drive... In some dizzys there can be found a felt pad when the rotor arm is removed, on to which a few drips of oil was added as a maintenance task to lubricate between the the outer shaft to avoid seizure over time...
Initial check of the vacuum advance was to remove the dizzy cap and watch for movement of the plate the points are mounted on as one sucked on the end of the vacuum pipe that was removed from the inlet manifold and watching as it sprung back when stopping sucking... Of course the maximum vacuum is generated on the over-run when the throttle plate is closed and inlet manifold depression is increased at which time the timing is automatically adjusted to suit.
Some cars were more succeptable to fuel vaporisation than others when attempting hot engine starts, and I think have read of where modern fuels may exaccerbate such issues, though if you suspect vacuum build up defeating the fuel pump if you remove the filler you could perhaps detect an obvious intake of air after an engine run..?
Hope this ramble assists in your appreciation of old cars, even if it does not solve any of your ...err... foibles... I am sure Arwyn, Spanner Juggler and others will be keen to help you get it all back to ship shape in jug time..
Happy Morganeering OLD STYLE... (-:
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Joined: Aug 2015
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Talk Morgan Enthusiast
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Talk Morgan Enthusiast
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Unfortunately the Ford Cortina 76 -82 manual covers the 1600 and 2 litre versions of the Ford Pinto engine which was never fitted to Morgans. The clue us that the actual capacity of a 1600 Crossflow is 1599cc!
A good manual to get (if you haven't got one) is Haynes 280 which covers the Ford Escort 75 to 80.
Re the failure to start, it could be a vapour lock have you checked to see if the fibre or rubber spacer is still fitted between the carb and the manifold, it should be about 5/16 to 3/8 thick.
Also, some engines I've worked on had a thick fibre gasket between the fuel pump and the block, and others didn't
I'd also remove and check the gauze filter located in the carb, it's underneath the fuel inlet stub. I run an inline filter between my fuel pump and carb but when I check the gauze filter last it was absolutely choked. Whilst you are in that area, check to see that the fuel inlet stub is as secure as it can be. It was a well known fault on the DGV carbs that they would work loose though heat and vibration and spray petrol on a hot engine.
My mod is to remove the stub carefully with pliers, coat with epoxy resin, refit then drill and tap the casing and the stub to take a small grub screw (I used 4BA x .125 as I had some to hand) .
You could also check the filler cap for a blocked vent hole
Arwyn
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