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MG MGA - Trouble starting

There's not been a lot of action on this site in recent times. So for people like me who miss the discussions about our great cars, I thought before lifting my bonnet and scratching my head, I would post the problem here to invite suggestions where I should start looking.
Yes it is a lazy approach but I do it as a service for those MGA BBS junkies who need their fix of solving other people's car problems!
It was a nice sunny day today, probably about 8 degrees, so I thought I would take my Mk2 for a spin. But it wouldn't start. It took what seemed about 5 minutes before eventually the engine caught and came to life. I then remembered exactly the same thing happened last time I used it, about 6 weeks ago.
Battery is fine, as it was able to turn the starter without problem for quite some time. Starter motor seemed to turn as normal. Petrol pump clicked in the normal way when I first switched the ignition on.
But once it did start, it ran nicely without a problem. Went for a 15 minute drive, parked up for a couple of hours, and then it started first time without a problem.
I am thinking either it doesn't like being left so long without use (a drive tomorrow will confirm or eliminate) or, more likely, I should check if the choke is operating correctly.
Any other ideas please? Thanks
Graham V

I wonder if you have the same problem as I have just had - could it be stale fuel ? It can go off in the fuel line and carbs in a short time.If the fuel is fairly fresh perhaps you might focus on the spark ? Coils seem to get tired sometimes.Keep us posted.
Roger
Roger Walker

Thanks Roger
The fuel is only about three or four months old, so I guess it’s unlikely to be that.
If the coil is on its way out, wouldn’t I get symptoms when driving and restarting albeit with a warm engine? I think I can test it with a multi- meter. I will look it up and check it out.
Thanks
Graham V

Hi Graham
Maybe the ign. points have closed down a bit
Years back I had a 1500 Cortina which always started well but if the points started to get out of adjustment you could wind it quite a lot before it would fire and it only fired at the end of cranking just as you let the key back from the crank position -you could push start it and it'd fire instantly, just wouldn't fire cranking--with the points reset it would be fine
Just a possibility maybe
Fuel is weird though, some cars seem to be troubled by it more than others
I have friends with MGs that sit in the shed for ages and fire up ok but then there's one particular MGB I have trouble with, anymore than 2-3 months and there's no way it'll fire without towing it down the road, then once it fires it seems ok
willy

That's ok, glad I could help---lol
William Revit

Something similar on a different old car turned out to be an intermittent starter motor fault, turned fine except for cold morning start but sounded fine. A few repeated test with an arcing screwdriver (not something I like) and the hit-miss was discovered.

I put it would be the starter based on the sound of it but just in time wonder if it might be, keep the status quo of my of my answers ratio.

Other than that of course its a vacuum/manifold leak. 😁

If you still have CB points then it'd be self-inflicted but I thought you'd progressed from such distasteful items.

Nigel Atkins

Could be moisture accumulation inside the cap due to loose or cracked cap. Once started, engine heats up & moisture evaporates until the next time car sits for a while & moisture accumulates again.
Nick Kopernik

Hi Graham

I took my car out on Tuesday after a couple of months in the garage and a similar thing happened. It started after about 6 cranks so not as bad as yours. However, in the summer even after a lay up it usually starts on the second crank at most. I have a high torque starter and electronic ignition and leave my battery on charge always.

I expect its a combination of factors; lower battery capacity, maybe some damp air in the induction system and condensation in the engine compartment on dirty ignition components and stale fuel.

In the winter months the temperature is lower so the energy that the battery can deliver is lower. "Cold temperature increases the internal resistance and lowers the capacity. A battery that provides 100 percent capacity at 27C (80F) will typically deliver only 50 percent at 18C (0F). The momentary capacity-decrease differs with battery chemistry." Extract from the battery university website.

Dampness on the ignition leads will create extra leakage, the reduced battery output could affect the spark energy as well.

If I were you I would give everything a good clean on the ignition side and charge the battery. Not much we can do about stale fuel unless you bleed some off or turn the fuel pump off before shutting the engine down (I have an extra security switch on the fuel pump)
John Francis

Stale fuel in the carb pots. Takes a while to get some fresh stuff pumped through. I find the same if she has been laid up for a few weeks.

I had a very embarrassing situation a week ago. I had been wondering why I had been having to put the battery charger on so regularly, often highlighted by a struggling starter turnover. I eventually got my head down under the bonnet and discovered a loose wire. It was the output from my alternator! It should have been attached to the battery terminal on the starter switch. Fiddling around under the air duct trunking it must have slipped off and fallen down out of view under the trunking last time I cleaned the battery power lead terminals. Trouble is that was about 2 years ago around Covid lockdown time! I have done plenty of short runs since then in daylight so the battery has only had to look after the ignition circuit. Hide my head in shame.

Steve
Steve Gyles

Steve. I'm not sure why the fuel in the float chambers would be any worse than the fuel in the tank, assuming no new fuel had been added to the tank. Is there any reason why it should be worse in the float chamber/ carburettor? My pump always runs for a few seconds to fill up the float chamber after it has been idle for a while suggesting that the fuel has evaporated a bit.

Ethanol fuel is hygroscopic so it is likely to get worse in the vented tank than the sealed float chamber. Ethanol fuel does have a tendency to gum up carburettors but that would result in a different outcome I think than the one Graham refers to.

Ethanol fuel has a shelf life of 6 months at 20deg C according to the Express.
John Francis

I routinely use a gasoline stabilizer in every engine which gets infrequent use or may sit unused for months at a time. This includes a tractor, mower, chainsaw, trimmer, blower, generator, snowblower, and the MGA. Stabilizers negate the negative effects of ethanol laden fuel and extend the useful life of the gasoline. Many brands are out there, but my preference has been Star-Tron, an enzyme enhanced additive.


Nick Kopernik

Thanks for the really helpful replies.
Willy. You weren't to know but I have electronic ignition so I can rule out bad points.

Nigel I guess it could be the starter motor except once warm, it started without problem. Unless intermittent as you suggest, but I did have a similar experience the last time I used it.

Nick, your moisture accumulation theory is an interesting possibility I think. But the car is garaged in a warmish garage. If it doesn't start first time when I try tomorrow, I will try cleaning the cap, etc and see if it makes a difference.

John. Condensation in the engine is certainly a possibility although I dont know how I can test for it or do anything about it - and I have never had it in previous years. I will certainly look at cleaning up all the electrics.

Steve. I dont think its stale fuel. The fuel tank is virtually full. I filled it up with ethanol free fuel on one of my recent trips, so is not more than a few months old.

I do still think it could be a faulty adjustment on my choke lever so will look at that too.
Will report back after I try it again tomorrow - many thanks
Graham V

Graham---Oh no not an electronic ignition--A modified car, What's the world coming to, No wonder it won't start-----
------lol
willy
William Revit

Graham,
the other case is now uncertain that it is the starter motor.

And I noticed I missed out the word 'not' in my last post as initially I did not think it was the starter and then changed my mind that it might be. No report back this morning, as the starter motor had previously been cleaned and it had a long hard life the owner proposed to replace it but the consensus was not to rush into that purchase.

As with yours I wonder if the problem is with something about the storage/parking, only overnight in the other case, but what, so many possibilities of variables and permutations of all the elements involved.

Have you tried talking warmly to the car before asking it to just spring into action from its inaction, a few kind words?

Nigel Atkins

Wily
Frankly I can’t see you point , or more correctly, you can’t see mine😊😊😊

Nigel
I have just done the opposite of what you suggested and told it exactly what I would do to it if it didn’t start first time. And it did

But the correct answer I am thinking is John’s, I am putting it down to condensation in the engine through lack of use. It fired up perfectly, first time, both yesterday evening and this morning.

I must use her more frequently.
Graham V

Graham.
I'm certainly not disagreeing with you if you frighten an inanimate object, it's condensation and you certainly have the correct solution but I'd be looking at what might be causing it and trying to prevent it, if that's OK for me to say so with you of course. 🙃
Nigel Atkins

Nigel
Of course it's ok for you to say whatever you want.
But you surprise me as I was sure you'd tell me that I should be driving more often and then I wouldn't have had that problem
Graham V

Graham,
it'd be a bit pot to kettle at the moment as I've not driven the midget since the journey back from the NEC two weeks ago. I waterless wash 'n' wax'd cleaned the paintwork last week, first time since the start of October, but I left getting the hose out to rinse the underside and wheel-arches and clean the wheels too late as three separate neighbours stopped to talk (to me!?) and it got too cold to start then and has been ever since.

I was wondering what might be in your garage (oh, to have a garage) that might cause condensation, mats or carpeting on the floor and/or walls?
Nigel Atkins

The garage is not too bad to be fair - its an integral garage, so the walls on two sides, and the ceiling all connect with our house.
But cant believe you havent driven your midget for two weeks, not like you at all
Graham V

Two weeks isn't unusual or more, think of all the times it's off the road having repairs by the idiot at home or sometimes idiots elsewhere and the putting right the repair of previous repairs going back to the work of con-men bodge artists calling themselves specialist experts. Plus other stuff and circumstances that prevents the use.

The piss-poor quality of the hood and its fitting by Don Hoods (Erdington) 6 years ago, it leaked at a seam after 3, means I can't drop the hood when around 10c when previously my limit of choice was 5c so the rear window plastic didn't crack nor my knuckles on the Tenax buttons. Kills most of the pleasure of a winter drive with the hood up.

Just before Covid started I was hoping to get more use out of it and as one point we did then more restriction and a second HGF on this car with Covid making getting the head sorted slow.

Pounds for mile with this car's ownership I could have owned and runs a fleet of MX-5s or perhaps an MGA (or two).

Many years ago I was offered a MGA body and could have had a spare RV8 put in it by my neighbours friend who raced MGAs and later had a half-share in a race BGT V8.

If it wasn't for my ownership of British cars I'd have a property with a double garage and two or three reliable Japanese cars.

Still not found out what the problem is with that car and the starter motor - so I've suggested damp. 😊
Nigel Atkins

Graham
I was watching this on TV (again) the other day and it made me think of you giving your MGA a good talking to.
https://www.youtube.com/watch?v=aYR3N-5rPJQ

Obviously, the paint on an Austin 1100 (or is it a Morris?) is far tougher than that on our MGAs! :^)

Colyn
Colyn Firth

Interesting, back to starting issues-
I've been helping a mate build a GT40 replica and yesterday was startup day--big test for our home grown wiring loom, it's got that much wire in it it's like an old telephone exchange, remember them, number please---
Anyway long story but it fired up first pop and cut out after about 3 seconds, fired it up again and it wouldn't take any throttle and cut out again
Checked fuel pressure and flow, both good, checked the throttle sensor ok, hooked the scanner up and there was no change in the airflow meter when it started--hmmm The engine is a Ford 5.0efi which has failure mode effects, so unhooked the airflow meter and started it up -bingo it ran fine, so the airflow meter has a fault---Pulled the sensor out of the housing and gave it a clean then notice a wasp had built his home in the venturi drilling for the sensor and completely blocked the outlet(no airflow) Cleaned it all up and reassembled and now it's running as sweet as a motherinlaw's kiss
Pesky wasp
Moral of the story, if your car's been sitting for a bit there could be animals living in it's private parts
willy
William Revit

Colyn
Yes that was a bit like me!
Strangely enough the assault on that car took place more or less opposite my dear mate's house in Lapstone Gardens, Kenton. Sadly we lost him last year but he was a great lover of that sketch.


Willy
Nice easy fix once you had discovered the cause!
Graham V

Yeah Graham--Most things are a simple fix------ -----once you find the cause
I've been waiting for your next question, 'What are failure mode effects', but then realized ,I don't think RV8's have got it, No actually I'm sure they haven't it's a USA Ford/Bosch thing, so you probably haven't come accross it
willy
William Revit

Willy
Good point. What the hell are failure mode effects?
Graham V

Ha ha Graham, I'll have to sit you up the front for not paying attention --
Failure Mode Effects, known as fme is one of the good features of the Bosch/Ford ecu
All ford technicians should be using it to their advantage during diagnostics but in real life most of them probably don't know it exists-
The only MG's that have it are the ZT260 and X-Power
How it works--
The vehicles with this ecu have everything on the engine controlled by the ecu and if there's a failure with one of the sensors or actuators the ecu will actually turn that sensor off and use the values from other relevant sensors to keep the engine running safely, sometimes with reduced performance. The ecu will try turning whichever sensor has the fault back on a couple of times in case it was a false fault, but if it's still out of spec.it'll remain turned off, but usually undetectable apart from the engine light will be on.
It makes life easy if you don't have diagnostic gear and are chasing a problem like a flat spot for example--The throttle sensor can be unhooked and tried like that--If it still has the same flatspot then it's not that sensor-plug it back on and try another like airflow meter unhooked- Ahh stumble gone, the airflow meter has a problem and with it disconnected the fme in the ecu has substituted a value for it
A common one on Fords is the egr valve position sensor out of whack--With this one the ecu simply turns the whole egr system off completely and runs as normal without it--eng. light will be on though
It's a really good system--as long as you know the vehicle has it, otherwise you can be trying to work out why something's not working when it's the fme system that's simply turned it off--just to trick you
There's a fair bit to it but i hope I've given you a rough idea of how it works
Cheers
willy
William Revit

Graham,
I’ve had similar problems when the temperature is cold. I found that the choke was not fully engaging. If I open the bonnet and pull the choke up manually and start the car by pulling the starter cable (with the key turned on), it starts right away.

Jim
JL Cheatham

Jim
Thanks
That was my first thought but I checked the choke and it was operating perfectly.
For your car, it’s a very simple task to adjust the choke cable so that it engages correctly

Graham V

This thread was discussed between 25/11/2021 and 04/12/2021

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