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Fan Belt Sizes for Side Valve engines

Posted: Fri Sep 06, 2013 8:54 pm
by gtt1951
Hello Folks,
I have asked this question in the Series MM Register Forum, but have not had many replies, so I'm going to ask in this one.
For those of you that have side valve engines, or even those that don't but may know, what size belts are appropriate for the 2 main variations of the 918cc engine
(a) without water pump
(b) with factory modification/water pump (not the after market add ons that did spring up) ?

One member has told me that a B33 belt should be used for (b) - this does fit, but was difficult to get on over the deep flanges. I had a belt supplied, by mail order from a Morris Minor parts supplier, that was a B36 - this is far too long.
They are adamant that this is the correct belt and that they have sold lots of them (all suppliers say that when parts don't fit).
I am aware of the threads discussing quality of parts but, at the moment, this is not suitable yet for that topic.

Belt Designation:
B = cross-sectional build (a V belt with a top flat of 17mm width, and a depth of 11mm).
the numbers following are the internal circumference of the belt in INCHES.

Please let me know what size belts you fit to these types of engine[frame]Image[/frame]

Hope someone can help,

George.

Re: Fan Belt Sizes for Side Valve engines

Posted: Fri Sep 06, 2013 9:12 pm
by bmcecosse
If a 33 is too tight, and a 36 too loose, seems to me a 34 will be just right!

Re: Fan Belt Sizes for Side Valve engines

Posted: Fri Sep 06, 2013 11:13 pm
by gtt1951
BMC,
That's what I think, but I need to know what owners have got. It doesn't help that all the pully flange sides are so deep.
Has anyone bought the belt for "water pump fitted" from a particular retailer in the south east of England, and found it to be OK?
I've promised to give belt details to one of our members in Holland (who has both types of engine).
With the B33 fitted, you can see the amount of adjuster bracket visible as "spare"[frame]Image[/frame]

Re: Fan Belt Sizes for Side Valve engines

Posted: Sat Sep 07, 2013 9:36 am
by MarkyB
In my experience the adjuster on the bottom of the dynamo is normally fitted the other way round, with the slot towards the engine.

Re: Fan Belt Sizes for Side Valve engines

Posted: Sat Sep 07, 2013 10:09 am
by gtt1951
You Know MarkyB, I think you're right. I hadn't given that a thought as all I was doing was changing the belt not removing dynamo etc, like what I had to do on my Traveller.
Unfortunately, I don't think that it would solve the problem of "insufficient" adjustment length to be able to use the B36 belt.
If it did, then the dynamo would be riding very high and, if the fan blades where fitted to it, rather than the water pump, then the tank would definitely get cut up.
I'll refit it the correct way round next time I'm doing anything with the Rad and bottom hoses.
Thanks, George.

Re: Fan Belt Sizes for Side Valve engines

Posted: Sat Sep 07, 2013 11:56 pm
by mike.perry
My adjuster is fitted that way round, easier to get a spanner on than having to tighten a clamp behind the fan belt. The fan on the dynamo should not hit the radiator as there is a hollow in the bottom of the header tank to give extra clearance.