Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Idling puzzle

Luddite my car ran perfectly up to three months ago before spending the summer abroad. When I came back it ran ok the first time but developed the problem the second time I used it. I intend to fit a manual joke instead of the automatic .

You could always fit a set of throttle bodies

Thought you might find this link interesting if this is your engine type..?

https://www.honestjohn.co.uk/forum/post/index.htm?t=18247

Could it be the ht leads.

Based on My long term experience, I would suspect an Electrical problem first and than a carb problem second.

MOR404, You typed that the problem occurred the second time you used the car after some months(?) of being laid up... which MIGHT suggest the lay-up was not the issue, or the conditions prevalent during storage..?

HT leads can and do fail though not with any regularity. Not too expensive or complex to replace anyway, have you checked in the dark for HT leakage..?

Perhaps a furl issue as fuel can degrade over lay-up or you fuelled up with some poor fuel, which is unusual though possible.

If your engine is of the sonic idle type, find out how that aspect operated as I have no idea.. I am pre-sonic idle..(-:

Good luck.

Manual choke is the way to go, they never worked well when new.

My '75 4/4 has always had a manual choke, you don't need it out for very long at all on the move.

You can check the resistance of ht leads using a multimeter. You tend to find problems with individual leads, so can pin point any issues by removing them one at a time.

It's never easy to assess running issues online, but my own 4/4 was not running great once up to temp. Replacing the dizzy cap cured the issue, upon examination I found a hair line crack in the old one.

It is relatively cheap to replace ignition components you may as well replace them if they are not recent.

From memory a set of Ht leads = £20-25

Dizzy cap and rotor (if required) = £10

NGK plugs = £6

Coil = £15

The above list is not far off an hours labour for a mechanic?

Assuming your points or electronic ignition is sparking and your timing is right, after replacing that lot, any running issues are likely to be down to the fueling side?

Good luck

Clubsport, that which you describe as a crack in the dizzy cap, could well be a... track... which can be created as the result of a high resistance elsewhere when condensation inside the cap can provide a less resistive alternate path, once the path is initially established, it is possible that carbon builds up creating the track and can etch it`s way into the surface of the plastic to look like a crack... Electricity like water, will ever take the least line of resistance, or if you prefer the easiest route.. Of course you may well already know this..

So today we replaced the distributor condenser and engined started without problems. I have taken all your suggestions and As I have indicated before, I replaced the coil, plugs, points, condenser, air filter , besides dismantling and cleaning the carb and now engine does not stall at 900 rpm on idling. Whilst on the way the car performed without any hitches. I am also converting the automatic choke to manual. My engine is fitted with a 4 in 1 exhaust and my mechanic is saying that probably my engine is also fitted with an upgraded camshaft. He set the timing and the car runs fine without any smoke. The purpose I am giving these details is to ask how would one know that the camshaft is not standard. I could not contact the precious owner to confirm. When we checked the timing marks with the strobe these were way out of line but he said that this does not matter once the engine is tuned and running well. I am not technical so I am asking your opinion whether this is the case. Thanks everyone for your input

I am mystified as You about various cams. My Mentor and Mechanic can tell a modified cam. I cannot. I am told that one of the reasons a Rover V8 in a Morgan responds very well to cam modifications. Seems the Rover cam is designed for a heavy SUV. If the Modified Cam is designed for a Morgan +8 it will be much more responsive and suitable for a Light Sports Car. There are other factors but frankly I am too inexperienced to identify them. When I changed from a Carb to an aftermarket EFI that was not designed for emission Laws My +8 Bitsa came alive. Not sure I have any more horsepower but the character of the engine now matches the needs of a Light Sports Car better than it did. I am now tempted to install a modified cam and try for more improvement.