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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 Midget and Sprite Technical - Wiper wheelboxes

I am fitting the wiper rack and wheelboxes on my Sprite. It would appear that they can fit either way round. The rack cable can go at the engine side of the wiper pivot arm, or the other way around with the cable nearer the back of the dash.
Is there a 'correct version for fitting this?
GuyW

IIRC the cable fits at the base of the wheelbox so to the engine side.
Jeremy MkIII

My memory is the same as Jeremy, although for interesting results, you could fit one each way ;o)
Dave O'Neill 2

Yep agree with Dave and Jeremy. Wipers park on drivers side.
Bob Beaumont

Ah, yes, it's the fact that they park when the rack cable is retracted that determines this. Otherwise they would work just as well with the wheelboxes either way up.

Which makes me wonder about wipers on left hand drive cars? Do they sweep and park on the left?
GuyW

YES
Dominic Clancy

Whatever you do check the way they go before putting the arms and blades on! I fitted everything and went for the big switch on - they went the wrong way and swept across the scuttle!

Problem was a LHD system but fitted in a RHD orientation. Luckily no damage though.
John Payne

Now I have my wiper boxes the right way up I find I have quite an assortment of the angled ferrules that fit onto the wiper shafts, under the scuttle. And they are not all the same! There are at least two options for determining the angle of the wiper spindle relative to the scuttle (and therefore the screen), and there are two different lengths of these spacers. I suspect that my assortment originates from a variety of different BMC vehicles!

Are frogeye and later midget and Sprite parts for fitting these whee!boxes interchangeable, or are the windscreen rakes sufficiently different to explain these variations?
GuyW

The Moss part numbers for the wheel box is the same for all spridgets using the square type wiper motor. It also uses the same fitting kits with the same chrome outer ferrule. Its reasonable to assume the ferrules under the scuttle are the same. There are no seperate part numbers listed for the frogeye or Mk 11.
Bob Beaumont

It was just a jumble of wheel boxes and various spacers and fittings that came with the car. I have ordered some new chrome finishers and can match these to the angles on the ferrules to make up a matched pair. I suspect some of these random parts are from some other completely different car. Spitfire maybe.
GuyW

Definitely worth checking part numbers before assembling it all. I was sent an "Midget" wheelbox by a s/hand parts dealer that turned out to have a different diameter gear to the good one on my car. If I hadn't spotted it would have meant different wiper travel on each side.
AdrianR

Thanks Adrian,I will look but I am not sure they would have part numbers on them.
GuyW

I would think it *should* have the Lucas part number stamped on it, but knowing what that should be is another matter.
Dave O'Neill 2

From memory there are about 4 or 5 different part numbers and they are stamped on the back of the wheel box. I'll see if I can dig them out.
Bob Beaumont

It wasn't the wheelboxes that I was concerned with, though now I see there are at least two different wheel cog sizes. But the angled sleeves that seem to be interchangeable between any of the wheelboxes.

I have several wheelboxes, but the best useable 2 pairs are marked 727 44A and 727 75A. The later has a larger steel gear wheel and the others have what appears to be a smaller fibre or nylon wheel.

The angled spacers aren't numbered and I don't now know which wheelboxe shafts they were originally fitted to.
GuyW

From photos and pictures I think the more likely pair are the 727 44A, but this number doesn't match with that listed by Moss or AH Spares' 37H6316. Maybe theirs are aftermarket replacements?
GuyW

Guy, I've just checked my wheelboxes which remain uncleaned but the numbers appear to be: RH: 72674A and LH: 72741A. Steel gear wheels. These are probably original from October 1958 so may be earlier versions than yours. I may have mis-read some of the numbers, but they seem to tie in with your likely ones. Their angled sleeves don't appear to be numbered. Hope that helps.
Bill Bretherton

Is that RH one right? All the other numbers we have start 727. Other than that, I am surprised they are handed. I cannot see any diffeerence! Maybe not looking hard enough!
GuyW

I've just checked the RH number with a magnifying glass and am as sure as can be it is correct. Maybe a very early version i.e. 726XXX before 727XXX? The "RH" is for my reference i.e. where I removed it from - may as well put it back there. There probably is no difference though as they appear identical.
Bill Bretherton

The 72674 number does exist - just found it on mgguru website (MGA wheelbox) and a Lucas part number pdf download. Maybe one of mine is from an MGA or was in the Frogeye parts bin in 1958?
Bill Bretherton

The frogeye wheelbox numbers are: up to 1960: 72674 afterwards: 72744 (bmc pt number 37H 6316) or 72850 They are not handed.
Bob Beaumont

Thanks all; this is both useful and interesting!
So that at least confirms which wheelbox pair I need to use, and its good that they are in fact the best in terms of condition, especially regarding the splined serrations on the top which always seem to deteriorate quickly.

Bob also explains why the numbers used by the suppliers are different in that they are BMC part numbers.
GuyW

Back to fitting up the wiper gear, but I am still struggling to get it to align properly - i.e. the rack wiper tube, wheelboxes and the spindles to go through he holes in the scuttle. Nothing seems to be falling into place as one would expect and I don't want to force things.

I am using what I think are the corrrect 72744 wheelboxes. I am still not 100% sure which way up they go. Should it be as the one fitted to the rack tubes, or the other way up as the one in my hand in this photo?

Neither way up gets the spindle to align with the scuttle holes. Its as if the first piece of rack tube between the motor and LH wheelbox is the wrong length, or maybe the wrong curve, but I have two such tubes and they are identical.

And then the other puzzle is the tube pieces that go onto the wheelbox to set the angle of the spindle through the scuttle. I have two sets and although on first inspection they appear the same, the angle is actually maybe 10 to 15 degs. different and I don't know which pair to use.



GuyW

These are the angled ferrules but none of these pieces have part numbers on them.
The sets on the left would put the spindle a little nearer to pointing skywards than the slightly longer ones on the right.



GuyW

Maybe there is something wrong here? The positioning of the motor would maybe impact via the first tube length on how the wheelboxes fit?

I have said before, but all of these smaller parts came in sundry boxes from the PO, and he in turn bought the whole thing from a garage dealer of uncertain reputability! Certainly various other parts in the boxes originated from completely different vehicles (Fordson tractor dynamo, Morris Minor door locks and wheels, Mini exhaust manifold...)


GuyW

Guy, Not sure I can help much but I just looked at what I could find and I currently cannot locate the wheelbox to wheelbox tube or the end tube. I also seem to be lacking stripdown notes so must have thought it obvious! So I don't know which way round the wheelboxes go either. However here is a picture of what I found - the angled ferrule in my hand is correct.


Bill Bretherton

The sets on the right look correct to me. Is there only one of the non chrome ferrules? The two shown appear different. The rack tubes should go at the top. there is some adjustment by positioning the rack tubes in the slots in the wheel box. I found the tube from the motor was quite hard up against the grommet hole when it passed through the bulkhead. I also left everything quite loose including the motor to allow some wriggle room. After a bit of adjustment it all slotted in.
Bob Beaumont

Sorry, that was maybe a bit mileading. There are of course two of the inner tapered spacers for each set. I only put one of each in the photo as at least one of the others was on the car.

The angle on the inner spacers matches the corresponding chromed outer piece. You cannot just swap the spacers around unless you then use the correct chromed piece or it wouldn't clamp up properly on the scuttle. However unless you hold them side by side one probably wouldn't spot the difference. I couldn't be certain from your photo Bill, which version yours is.

However on mine, there is a difference. The spacer on the right has a reinforcing rib on the outer surface that extends the full length of the longest side of The spacer. On the other version, the rib stops about 3/16" short. You can see it in my photo. Whether this is a consistent difference tied to the different angles I don't know.

GuyW

Bill, when I have got this sorted I will have a spare centre tube piece that you are welcome to. In theory, I should have a spare for the short end piece as well though I haven't located that as yet!

another question - when dealing the spindles in the scuttle to stop rain getting in behind the dash, should I use the oval rubber washers above and under the scuttle skin? I think the illustrations only show one but I do know these are prone to leak.
And maybe add some silicone sealer on the underside?
GuyW

As to those ferrules, the set on the right in my photo - the ones that Bob is supporting, project the wiper spindle through the scuttle at a slightly lower angle. If the wiper arm then operates through an arc which is in a plane at right angles to this spindle, then this would suit a more upright windscreen. I wonder, are the frog and the later car's windscreens at different rakes? My frog screen isn't mounted yet, so I tried positioning one of the stanchions alongside the screen on my '71 car. Hard to tell, as without it bolted down it would be difficult to be sure but I think the later car screen is maybe slightly more upright.

The wiper ferules on my later car are the lower angled variety (RH pair in photo) but since I built that car from a similar state of disassembly, 25 years ago, I couldn't be 100% sure that one is right either!
GuyW

Bob - "The rack tubes should go at the top"
Is that how yours is then? The Moss exploded parts diagram, which I always assumed was taken from a workshop parts manual, shows them the other way up with the spindle above the rack tubes. That is, as the one I am holding in the photo, rather than the one on the right attached to the wiper tubes.
GuyW

Guy
Apologies the rack tubes are at the bottom. the tubes on my car are also slotted into the end most slots
Bob Beaumont

Guy, thanks for the tubes offer - I'll have a bit of a tidy up tomorrow (!!) and see if they show up. My (internal) ferrules came off the car so I assume are original. I can measure the angle if that would help? I need new external chrome ones so will get some from Moss.

Re. the wheelbox/ rack orientation I too assumed the Moss diagram was showing it the "right way up" as you say Guy and as Bob has now confirmed.
Bill Bretherton

Bill, can you check the detail that I described for the inner ferrules. Does the strengthening rib extend the full length down the outer surface of the long side, or does it stop a little short of the pointed end? Look again at that photo I posted earlier.
GuyW

I'll check in the morning Guy and post back.
Bill Bretherton

Rib stops a little short:


Bill Bretherton

Another picture to emphasise angle:


Bill Bretherton

Guy

The rubber seals are just under the chrome ferrule above the scuttle. I only used one each side and have had no leakage problems. I carefully sealed them when I fitted them with some windscreen sealant.
Bob Beaumont

Ok, thanks to you both!

Bill your spacer is of the slightly higher angled sort, i.e. the wiper spindle will point slightly more skyward than the version I have on my 1275 car ( which may not be correct anyway!)

The difference is a bit less than 10 degrees. I am not sure if this is a known and intentional change, possibly related to the change in windscreen after MK1 Sprites, or some inconsistency in manufacture with a change of supplier perhaps. Oddly, both Moss and AH Spares list the same part for all models for the chromed piece. Neither list the inner spacer as a separate item from the wheelbox, though it just slips off.

I cannot see that it matters much which version is used, so long as the angle on the spacer matches with the angle on the chrome finisher. If one was to use a mis matched pair it would never clamp uniformly onto the scuttle which would almost certainly then leak.
GuyW

Guy yes your right. The angle and length of the inner ferrule is the critical issue. Another point to note is ensuring sufficient clearance between the rear edge of the bonnet and the wiper arms. Its very close when the bonnet is lifted. The original wiper arms are ok but the later fatter ones can foul the rear edge.
Bob Beaumont

Silicone sealant is a sensible precaution. I assembled mine without any silicone (or windscreen sealant as Bob has used) and it leaked like a sieve the first time it rained.
Jeremy MkIII

I did the same as Bob, one rubber gasket and windscreen sealant - cleans up with white spirit and does not react with the paint - well mine was fine !

I would not use silicon.
richard b

This thread was discussed between 19/09/2019 and 22/10/2019

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