MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Starte not Disengaging

Having run my car every month or so and even yesterday to give it a good clean it always started perfectly.

Today when I intended to take it out for short legal run it seemed to be turning a lot slower although it was a very cold morning. But all fine with starter until it did ctualt start the engine and although it carried on runing there was mechanical noise. I have now removed the starter and the cog was jammed solid against the body of the starter, i.e. it hadn't disengaged. It didn't seem to wnat to unjam until I gave a light hammer blow and it popped back. I tried to make it stick on the bench but it just behaved itself.

My options as I see tham are: -
1) Just put it back and hope it nevere happens again.
2) Get a new original design starter from Moss By the way the current problem one is one of these about 3 yeras old.
3) Buy a high torque permantly ehngaged one, probably also from Moss. More expensive but disengaging couldn't be a problem.

All advive and thoughts welcome asap.

Paul
Paul Dean

Paul,
as with many repairs, servicing and maintenance it often boils down to just clean and lubricate, so it could be as easy as that.

Or if you lack confidence in then replace it with a high-torque pre-engaged and you'll save a bit of battery pull and power at each start and some starts in some circumstances could be easier (useful for when you other have problems to resolve) - and the wirl
instead of clatter when starting is more pleasant.

Moss are not the only suppliers.

You don't need a high-torque starter but you may want one, I didn't need a high-torque but I have one and wouldn't go back to the (very) old sort willing.

Others will no doubt feel and advise differently.



Nigel Atkins

Paul

The pre engaged starters do disengage. All that happens on starter pull is that a solenoid throws the non turning cog forward to engage the flywheel. Once its engaged the starter turns it. when you release the starter pull the cog pulls back out. No gnashing of teeth and only a very low current across the starter switch (sufficient to operate the solenoid).

Like Nigel, I would never return to the original starter.

Steve
Steve Gyles

Hi Paul
you don't really need a high torque starter with your engine, I still use an inertia starter with my 1950cc motor without problem.
I used to have starting issues but the problem turned out to be caused by poor connections in both the battery cables a poor earth at the battery end.

I did try a high torque starter but, my hybrid combination of 5-brg engine grafted onto a High-gear 3-brg alloy bellhousing just wouldn't work with it.
I tried a few different high-torque starters and they either wouldn't disengage from the flywheel, or would not engage it to start it at all.

One of them went into dead short and almost melted out tbe full-length of the battery cable.

So be wary if you do try one

Cheers
Colyn
Colyn Firth

I think if it didn't disengage the pinion could be turning as high as 50,000 rpm!
Art Pearse

Art,
I never thought to work out how many revs the "permanently-engaged" pinion would have been doing whilst it was being driven round by the engine.

No wonder it made a loud screaming noise once the engine started, I only left it running for a few seconds before switching off.

I removed and refitted the high-torque starter to see if I could get it to work but, although it obviously spun the engine far faster than my standard inertia starter had, it still would not disengage and so I abandoned the idea.

I actually gave the high-torque starter to a friend of mine who is fitting a 5-brg MGB engine to an MG ZB Magnette and it apparently works fine on his car.

Cheers
Colyn
Colyn Firth

For me the biggest benefit of the pre-engaged option is the low current across the starter switch for the starter solenoid. Even the modern crappy ones can cope quite happily and don't burn/arc out over time. For those who are not up to speed with the concept, the battery cable connects directly to the starter cable, by-passing the normal make/break connectivity across the starter switch. For ease of wiring and connection to the other electrical circuits the battery cable, starter cable and brown power cable share the same terminal post on the starter switch. All that is on the other side of the switch is the cable to the starter solenoid.

Steve
Steve Gyles

Problem solved at no cost.
Having looked again at the problem Moss starter I could see the cog was slightly damaged so I decided putting this unit back and hoping was not an option.

But I had a failed original starter on the shelf. I always suspected this had failed due to brushes wearing with high mileage and changing brushes is quite complex so I had just replaced it with the Moss one a few years ago. So I had a thought and took the shaft and engagement mechanism from the old original starter, i.e. the moving bit, and fitted this to the Moss body, i.e. the stationary bit, with it nearly new brushes. Fitted it to the car and it’s working so hopefully that is a solution. Too cold to test on road this week so far.

Many thanks for discussion. If buying new I would probably go high torque. By the way does the high torque one fit both high and low starter positions.

Paul
Paul Dean

Paul

Glad you got it sorted. The other option would have been to replace just the cog assembly (bendix). Some motor factors still supply them. I did mine many years ago and I have the bendix compressor tool (photo) so that the retaining cones (similar to valve spring cones) can be removed. However, starters do vary and the one described in the workshop manual has a different retaining mechanism.

My pre-engaged starter uses the upper position. I don't know about the lower. The other advantage that I didn't mention above is that the starter cog engages with the front of the teeth on the starter ring. Very useful if the rear side is badly worn from the whirring and gnashing of teeth from the original starter.

Steve



Steve Gyles

Well done Paul.

There's a great John Twist (University Motors) YouTube video of JT working on a M35J, it would excite an H&S compliance officer.

I don't know about the fixing positions but you could ask the manufacturers I've seen a WOSP with a multi-fit type ring mounting plate but their website, and Powerlite's, like so many others has omission on details for some models of their products and model specific fitting instructions no longer available to view.

Powerlite (MGA, replaces inertia type) - https://www.powerlite-units.com/starters/rac401.html

WOSP (LMS002 for MGA) - "... and the starter offers an infinite number of positions it can be mounted in due to its ability to spin 360 degrees on it’s mounting flange plate." - http://www.wosperformance.co.uk/products/starter-motors/



Nigel Atkins

My interest in high torque starters in low position is just out of long term interest. For now I will carry on with my fixed original in high starter gearbox, particularly since I changing the switch a few months ago transformed its performance. But I do have a spare 1500 gearbox that is low starter which hopefully I never need.

Thanks again.

Paul
Paul Dean

Paul,
things change so you'll need to check in advance as much as you can as to what's available at the time. Parts and suppliers for many reasons come and go. WOSP look like they might make up stock as required but I've no idea of the business set up and how it could change.
Nigel Atkins

I have a WOSP starter fitted to a low-starter plate 18V engine. (Not much modification here ;-) I had to grind a little from the bloc to make it fit but have been using it happily for two years without problems

Dominic Clancy

This thread was discussed between 02/04/2021 and 10/04/2021

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.