Morris Minor Owners Club

Hi all.
I have a 1954 series 2 with a gold seal 803cc engine. It has its original large pulley dynamo and the engine has the early type timing cover.

Recently the old 813mm fanbelt has seen it's best days and I purchased a new 813 fanbelt which will just not fit, even with the dynamo unadjusted against thd block. The original belt is stretched and a later 825mm fanbelt is just too big.
Has anyone come across this issue before?

Also any suggestions on a more appropriate size belt?

Many thanks!

You state that you have previously fitted a 813 fan belt but personally I would fit the later smaller dynamo pulley 12G2102 so as to make the procurement and fitment of the 813 fan belt a much easier task.

Yes it happened to me, the dynamo pulleys can differ in size, so there isn't a standard sized belt. I measured around the circumference of the pulleys and brought a B section belt to that size.

Thanks guys. I really do want to keep the original set up. There was no fan belt on it when we restored it so no comparison. I had assumed mine used the standard later type A section belts (car is June 1954) but wonder as it is a bmc replacement engine could it need the earlier B section. Is there any way to check the bottom pulley profile to see which it should be? I suppose best option for length is to just use string to measure an appropriate length?

All this talk of different Belts, by A , B etc, I thought I'd do some looking as to how they are coded ....

This might be useful for some: https://www.regalrexnord.com/brands/Bro ... er-labeled

Just reviving this to say that having got Basil's engine out to do a few jobs, when I went to remove the fan belt (never having done it before) I found that there wasn't sufficient adjustment on the Dynamo.
It's hitting the Water Pump Bolt. Not a problem on this occasion as I was removing the bottom pulley.
I think I need to compare the fitted belt with the spare one that came in the boot when I brought him....

10 Minutes later....
So I've measured the 2 belts, exterior circumference. The one on the car approx 810mm, the one in the boot as the spare, a paltry 795mm
The one in the boot is a Ferodo 903, which I suspect is an old 'spare' dating from the time the car had it's 803 engine.

Anyone have a recommendation for a 1098 with Dynamo?

I've been looking and ESM offer one that's 825mm, other sellers are offering 813mm, 838mm, even 865mm

I have a 1098 with dynamo and I fitted the ESM belt a few months back. No issues. I bought two belts actually so as to have a spare.

1098cc with dynamo.
I have used two makes of vee belt. 1. Quinton Hazell QBA825, 2. Gates 6213MC. Both 10 x 825. A Gates is fitted at the moment.

Thanks guys
The one on the car, I've deciphered the number and it is 814mm long, so my measurement of approx 810 was quite close.
There's no way it fits over the pulleys with it all slackened off.
I did some digging back through the old parts catalogue the original belt was 13H 859 for both the 9M and 10MA engines, which these days reads across to an 813mm belt, which is what ESM sell for " 948cc and Late 803cc".

So something changed somewhere over the years...
I'm just accepting it as one of those things and going to order an 825 belt. They're very common on classic mini so plenty around.

I ordered a belt from ESM listed for a 1098cc engine with alternator conversion.
Maked as 825mm it would not fit over the pulley with the alternator slackened right off.
Ordered two more belts from a Mini specialist at 838mm which fitted perfectly so I guess the alternator conversion on Willum may be "non standard".
A bit of experimentation as always paid off, hopefully no more screeching fan belt!
Most embarrassing in the high street!

As someone has already stated, the pulley diameters vary between engines.
My 2 sidevalve engines, both with water pumps fitted, take different sized belts. I also have 803cc and 1098cc engined cars, so need a varying number of belts.
The sidevalve belts are all wider flat-botttomed "V" profile belts and I get mine from a company called Bearing Boys, see
https://www.bearingboys.co.uk/search.cg ... =fan+belts

Use either thick string or tape to measure the length then, of course, measure the required width, depth and choose a profile.

The sidevalve belts from ESM didn't work for my cars.

George.

Well the 10x825 belt arrived today and it still isn't long enough.
No way it'll stretch over the Pulley and despite the adjustable stay being only mid-slot, the dynamo is hard against the Water Pump bolt and also the terminal protector at the rear.
The one that was on there must've been fitted by removing the fan from the water pump
.
I tried to resize these images, but for some reason this board still insists on making them full page width
. .
The respective Pulley sizes are approximately :
Crank 4.6"
Water Pump 4"
Dynamo 3"
Back to the drawing board...
I cut the 'old spare' and used that as a starting point. I aligned it in a position to slip it over the Dynamo pulley and it was approx 40mm too short.
So I've now gone for the 838mm long, supposedly to fit a Classic Mini Cooper with Alternator

FROM PIC IT LOOKS LIKE YOU ARE NOT AT FULL ADJUSTMENT

SEROWMANMICHAEL wrote: ↑Tue Jul 18, 2023 9:21 pm FROM PIC IT LOOKS LIKE YOU ARE NOT AT FULL ADJUSTMENT

Well firstly STOP SHOUTING....
I explained, and posted the images to clearly illustrate, that despite the adjuster being at mid point, the Dynamo cannot be pushed in any further as it hits the Water Pump Bolt as the terminal protector at the rear of the Dynamo.
I even put nice Red Arrows on the images to help people see the problem.

Look at the images again.

As regards the rear of the dynamo fouling the mount bracket - there are several different rear dynamo mount brackets.
The one most suitable for your application has the lower side of the bracket removed in the area where you are getting terminal contact. Or remove part of your existing bracket. I suspect that the above is the correct rear mounting bracket for your dynamo.
The rear dynamo mounting bracket can also have mounting slots so as to adjust the fore and aft position of the bracket so as to increase the clearance.
The dynamo front flange hitting the front bolt is not unusual especially with after market dynamos. Just reduce the flange in the area of the flange bolt contact with a file so as to allow the dynamo to move inwards.
At the rear- what is marked with the red arrow can be removed. The genuine Lucas dynamo I have does not have that extension to the terminal insulator, the extension is not required and it serves no useful purpose.

I’m pretty sure on mine the bolts are long enough that when slackened right off the dynamo can be pulled forward to allow it to swing to full adjustment and get the belt over the pulley. Without pulling the dynamo forwards it will foul in exactly the same way.

philthehill wrote: ↑Wed Jul 19, 2023 10:09 am

Thanks for all that good info phil.

I looked at the 3541 Parts List and only saw the bracket matching the one I had fitted.
When I first got the car, I tried adjusting the loose fan belt and then had to dress out the adjusting link because otherwise it would catch the Pulley vanes otherwise.

The Dynamo Case, on which of course the end plates could have been changed, identify it as a 1967 C40 22700L.
I must admit I don't recall seeing that extension to the terminal insulation on other Lucas Dynamos, but then other than this one, it's been a few decades

I've got a slightly longer belt coming, I'll see how that works out. I'd rather not be dressing out the Dynamo front plate.
The extended insulation on the rear plate will be the first to go.

svenedin wrote: ↑Wed Jul 19, 2023 11:38 am I’m pretty sure on mine the bolts are long enough that when slackened right off the dynamo can be pulled forward to allow it to swing to full adjustment and get the belt over the pulley. Without pulling the dynamo forwards it will foul in exactly the same way.

That's an option I hadn't thought of, although it shouldn't be necessary with the appropriate length belt for the configuration of pulleys.

geoberni wrote: ↑Wed Jul 19, 2023 1:55 pm

philthehill wrote: ↑Wed Jul 19, 2023 10:09 am

Thanks for all that good info phil.

I looked at the 3541 Parts List and only saw the bracket matching the one I had fitted.
When I first got the car, I tried adjusting the loose fan belt and then had to dress out the adjusting link because otherwise it would catch the Pulley vanes otherwise.

The Dynamo Case, on which of course the end plates could have been changed, identify it as a 1967 C40 22700L.
I must admit I don't recall seeing that extension to the terminal insulation on other Lucas Dynamos, but then other than this one, it's been a few decades

I've got a slightly longer belt coming, I'll see how that works out. I'd rather not be dressing out the Dynamo front plate.
The extended insulation on the rear plate will be the first to go.

svenedin wrote: ↑Wed Jul 19, 2023 11:38 am I’m pretty sure on mine the bolts are long enough that when slackened right off the dynamo can be pulled forward to allow it to swing to full adjustment and get the belt over the pulley. Without pulling the dynamo forwards it will foul in exactly the same way.

That's an option I hadn't thought of, although it shouldn't be necessary with the appropriate length belt for the configuration of pulleys.

Seems you have a different C40 variant to me. The picture is of a spare of mine, it's not the one on the car but is identical to the one that is. Lucas 22715F year 1967. This is the stepped body type which I see yours is too. I do not know what, if any, the significance of the different models is except to say that a C40L is the long variant and is quite different.

I also checked that my memory is correct and yes indeed, I loosed the dynamo nuts until they were very loose, pulled the dynamo forward and it then would swing to the full adjustment and allow me to fit the fan belt. I remember being taught to do exactly this by a mechanic friend over 30 years ago. When I refitted the new belt a few months back I used this technique without even thinking about it because it was what I was taught.

svenedin wrote: ↑Wed Jul 19, 2023 2:34 pm

Seems you have a different C40 variant to me. The picture is of a spare of mine, it's not the one on the car but is identical to the one that is. Lucas 22715F year 1967. This is the stepped body type which I see yours is too. I do not know what, if any, the significance of the different models is except to say that a C40L is the long variant and is quite different.

I also checked that my memory is correct and yes indeed, I loosed the dynamo nuts until they were very loose, pulled the dynamo forward and it then would swing to the full adjustment and allow me to fit the fan belt. I remember being taught to do exactly this by a mechanic friend over 30 years ago. When I refitted the new belt a few months back I used this technique without even thinking about it because it was what I was taught.

There's an awful lot of numbers for Lucas Dynamos, this website pdf is quite long, but still doesn't include all of them, it's missing your 22715 for starters.
http://www.classicvehicledata.com/wp-co ... 46to60.pdf

As I've mentioned previously, all my classic car experience, decades back when the weren't classic, was Ford and Vauxhall and I never had to mess around loosening the Dynamo as you describe; it was always just slacken the tensioning bar, swap belt over (or replace broken one) and set tension again. In fact I usually didn't have the 2 main bolts really tight, so there was only the single bolt to slacken. All done in a few minutes.
Perhaps it was more of a BMC/BL thing that you needed to mess around moving the Dynamo forward.
About as bright an idea as mounting the Coil on the top so it really gets a good high frequency shaking all the time.

Just fitted an 838mm long belt.
Fits over the pulleys and adjusts to correct tension with around another 15-20mm of adjustment if/when it stretches.
Jobs a good'un.
As I have the 825 belt, I might fit that, with all the fuss of moving the dynamo forward and backward, and keep the 838 as a spare.
At least then I'll know the spare is a simple fit should I ever need to do it 'roadside'.