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MG Midget and Sprite Technical - Is this standard or aftermarket?

Hi,

On my 1961 MG GAN1 engine is this device. My best guess is that it's an oil catch can and maybe fume separator. I can't see what's going on at the bottom; it seems to be attached there and maybe returns oil back to the sump.

(Wrong time of year to be crawling underneath for me as the car lives) outside.

The previous owner said that the car has had a rebuilt engine and, if for no other reason than it's painted green, I wondered if this device was standard on something else from BMC. Ie something that donated a complete engine.

For the moment I'm of the,
'if it ain't broke don't fix it' mindset but am nonetheless curious. Is it at least harmless?

Many thanks






P Peters

Hi,

I have a 1965 MKII 1098 and that’s exactly the same on mine.

They are for the oil breather system. The green cylinder contains a gauze filter. The other on top of the inlet manifold is the valve that controls the suction to make sure the flow is one way.

If it has been rebuild, both of these should have been cleaned out to ensure proper operation.
James Paul

Well it's not aftermarket but it's not standard for a 948 GAN1. The thing on top is a PCV valve or Positive Crankcase Ventilation valve. It uses vacuum from the inlet manifold or carbs to give a negative pressure in the Crankcase to extract fumes etc and stop leaks. The part lower down is the breather canister/filter on the front tappet cover. It has a gauze filter inside and is where the PCV connects.
These items are off a later car such as a 1098cc midget as James has pointed out.
It could be that your car has had a 1098 engine fitted - worth checking anyway.
John Payne

As said, you may have a later (1098?) engine. Check engine number on the plate at top right side of engine block. Or it may have 1100 cast into the block in raised numbers below the front tappet chest cover.
The flat topped carb lids are also typical of a later engine.
GuyW

The Mk1 had a hose coming from the rocker cover to the front carb filter housing.

See page 59 of the Original Sprite & Midget The Restorer’s Guide by Terry Horler, it also has lots of useful information even for those not too concerned with originality. –
http://www.amazon.co.uk/gp/product/1906133336

Blatant plug - if anyone wants a copy of this book my 2011 print, hardback, can be purchased for a reasonable sum (used but not abused condition).
Nigel Atkins

This is the Mk1 breather set-up. The canister on yours appears to be at the wrong angle, so it may be from a different model of car. The hose looks as though it's in danger of being rubbed through on the radiator neck.


Dave O'Neill 2

I thought the same about the hose as Dave, looking at the photo on page 81 of said publication of the later set up, as original post, the hose is longer so routed less directly, below the radiator extension and in front of the carbs heatshield.

I think it might just be the angle of the (P Peter's) photo that might give the appearance of the canister being at a different angle (I could be wrong of course as I often am).

The photo on page 81 shows the canister doesn't have a lot of clearance with the coolant bottom hose and the carbs heatshield.
Nigel Atkins

Photo of my 1098cc during rebuild and all connected up





James Paul

As a GAN1 948 it shouldn’t have a canister at all, the timing cover is just a plain one and the front tappet chest cover has a metal breather pipe going down the side of the block. It’s basically the same as the Frogeye.
I’d say it’s very likely to be a 1098 which is a nice upgrade. As well as the engine it would be worth checking if it has the original smooth case gearbox or the 1098/1275 ribcase.
John Payne

If someone has one of that style of canister on a tappet chest cover going spare, I would be interested in buying.

Currently my 1098 engine has one of the down draught tubes jury rigged with a long flexible hose back up to a pcv device on the manifold. It works, but isn't beautiful!
GuyW

James,
your breather hose looks the same thing as P Peter's. shorter and wider than others I've seen, have you used breather hose or just 1/2" hose?

https://www.minisport.com/bau5065m-breather-hose-metre.html

And is your heatshield standard, again I've not seen one like that - but I've not seen many 1098cc engine bays or can remember the details.
Nigel Atkins

Guy,
be aware Minis had a choice of two (concave/convex covers) and there are two different part numbers for the Spridget but I've no idea what the difference is so you need to see any offered, I'd guess with the Minis being much more popular than Spridgets that you are more likely to see an original one from a Mini now but I could well be wrong.
Nigel Atkins

Thanks for the alert Nigel. I don't remember too well from any of my Minis that I had, other than I thought they attached to the timing chest cover? Buyy they were a very long time ago! I am after one that attaches to a tappet chest cover as in James' photo.
GuyW

Hi Nigel,

I ordered the same hose that is on your link. Part number. BAU5065M

The heat shield is an odd one. I bought a new heat shield as i thought that the one that came with my car was almost bespoke, other than it had a patent pending code on it.

So when I went to fit the standard shield I was surprised to find it didn’t fit.
The exhaust manifold that I put back on my car is the one above and the middle pipe sticks out so much it gets in he way of the standard heat shield.

So I re-installed the one you can see which isn’t going to be very good at stopping heat.

I do sometimes wish I knew more about the history of my car.




James Paul

Guy,
I was thinking of the tappet chest ones for the Minis, sucked-in type cover and flattish type and I've vague idea there might be more than one type for the Spridgets but I could be misremembering with that.
Nigel Atkins

Hi James,
another of my mistakes then about the hose but if you bought a metre of it you might have enough to run a longer length that pushes itself away from the rad extension - but I might be wrong about that as I forget how much hose it takes.

Again IIRC there's a Mini Copper heatshield with a gap in the middle but whether it'd fit that manifold I don't know.

There looks to be a lot less surface area on your heatshield and it doesn't go behind the spacer blocks so how effective it is you might discover in warmer use of the car. Yours looks to be more of a fixings plate than heatshield. but some of the shields on single carbs conversions look to be Twiggy like.

Nigel Atkins

I think you’re right about the two different profiled covers for the canister, in an attempt to make it more rigid to eliminate oil leaks.

Guy, Moss appears to stock the canister front cover. It’s not illustrated but in the list it says “note: with oil separator”.

£22.
Philip Sellen

James

the LCB manifold can foul the standard heat shield. In one of the BMC tuning books it mentions that the shield has to be slotted in the middle to accommodate the centre branch. Certainly that's what mine has.
The Cooper S as Nigel mentions has a different shaped heatshield which is in two parts and clears the centre branch. The S carbs though have a thinner spacer between the carbs and the manifold. It doesn't have the retainer for the throttle cable as per the standard midget heat shield and you have to mount one on the manifold. Using the thicker midget spacers does mean the cable run is less smooth though.
Bob Beaumont

As I have bought the heat shield I thought that at some point in the future I’d see if I could adapt it to fit.

Worth a go as I’ve lost money on it anyway.

I’ll report back at some point on how I get on.

On the hose, I found out that by twisting the PCV valve to the left more it helps the hose clear the radiator as it was only just touching it before.

Thanks as always!
James Paul

Browsing through online photos it seems some heat shields are fitted agaist the manifold with the phenolic spacer on afterwards, and some assembled with the spacers going on first. Maybe that's right according to different engines? off hand I couldn't say which way round mine are but I recall it only assembled one way with twin carbs fitted. (other engine has a HIF and shielding and spacers fit differently)
GuyW

Thanks Phillip. Moss do list the tappet cover with oil separator, but unfortunatly currently out of stock.
GuyW

Thanks all.

The plate on the engine is 8G16 R N19545

Which seems to come up as a gold seal replacement engine. That matches what seller stated but I can't find an invoice in the paperwork.

The radiator pipe has about 1/8 inch clearance from the catch can.

Going through the paperwork looking for engine details I came across detail of 11/16 anti roll bar (definitely fitted as I can see it) and lowered 400lb front springs.

I'm not sure the uprated springs are still fitted as it's a very comfortable ride and I imagine 400lb springs would be very harsh.

I actually spotted my car on MGEXP here:

https://www.mgexp.com/registry/1961-MG-Midget-MkI-GAN10000.38548/

With different rear wings and a better fitted bootlid.
P Peters

The 400lbs springs shouldn't give a harsh ride unless the dampers are adjustable and set to hard/firm. You could do a simple test without getting your hands dirty, go for a good drive and where safe to do so brake hard if the nose doesn't dip too much you don't have the standard front road springs.
Nigel Atkins

P P

400lb springs and my front end still dips(!) - but not as badly as with standard springs so the tendency for the rear to lock up under severe braking is reduced but not eliminated.

I don't think the 400lb springs affected the ride on the road too much but polybushes definitely made it harsher.
C Mee

Colin,
is your car only set up for hill climbs!?

If you were to go back to standard front springs, particularly worn tired ones, I think you'd notice more dipping.

Are you saying your rears lock up with your front or before your front lock up? Are your rear wheels off the ground?

It depends on which polybushes you fit as to if/how-much harsher the ride is, anything for motorsport will probably be harsher than just road use.

Also it may be how much you are use to soft or harsh on the car previously.


Nigel Atkins

Ive been running my midget on 400lbs frontsprings for 20 years now
First with my 1500 and changed to 1275 hight springs 340/60?lbs after converting to Kseries because of the weight loss.
Missed the rigged feeling of the 400 ones so have put them back in with some lowerin-grings.
Cant say you need them for your spridget but Im so used to the 400lbs that I dont want to run without them anymore.
A de Best

Hi Peter,
I had discovered your car too on MGEXP while on my hardtopidentify quest.
Looks like a Clifford Enginering top.
Do you still have it?
A de Best

Is there any sign of a brand/name on yours?





A de Best

In response to A de Best, the hard top looks identical to the ones in your pictures but there is no manufacturer's name anywhere. Nor any marks where one might have been.

I don't know if such a top would suit your later midget because it fits the removable sliding windows and attaches via hooked bolt to the atachment points for the removable hood frame. I can take pictures of any other part of the hard top if it helps you.

It's functional but tatty. I would say fairly low quality but that might have been the standard back then.

The rear part clashes with the hooked soft top retainers causing a gap.

There is a metal reinforcement embedded in the fibreglass probably to hold the shape but also to provide a metal anchor point - well just a loop of metal for the hook to attach.

It would be fairly easy to repair then take a mold off but that might infringe someone's copyright.

There is an aluminium strip over the side windows to help drain rainwater away from there. I'll add a picture of that in the next post since I can only add two per post











P Peters

This is the aluminium part. FWIW both sides don't fit nicely against the fitting for the soft top button in the corner. Again, many years' abuse might have pushed things out of shape.

Just to round things off, this hard top works by hooking over the front windscreen frame then bolting to the two hood frame anchors. It's quite solid like this.


P Peters

When I purchased the Sprite it had a rubber pipe joining the cannister on the chain cover to a beautiful "Mocal" oil catch tank. There was no trace of oil in the tank and in an attempt to cure the rear crank oil drip I removed the tank and fitted the pipe to one of the K&N air filters. This didn't work so I bought a Smiths PCV valve as shown in some of the pics. This stopped the oil leak but every now and then there would be a cloud of smoke from the exhaust. I reasoned oil was being splashed against the opening to the cannister and this, rather than mist, was being sucked into the engine. I then removed the pipe from the cannister, blocked off the outlet stub and connected a pipe to the rocker cover / PCV. There is now no smoke from the exhaust and would you believe it, no drips from the engine!

Jan T
J Targosz

"There is now no smoke from the exhaust and would you believe it, no drips from the engine!"

I think you need to check your oil level - I suspect you don't have any! ;)
P Peters

Before I bought the Sprite the engine had been rebuilt by top class A Series engine tuning shop. The £3,500 bill included fitting a Peter May rear crank oil seal. There was such a bad oil leak from the bell housing that the car was unuseable. After advice from this site I removed the engined, binned the lip seal and replaced it with the original scroll. This made an enormous difference but there was still a slight drip. Fitting a PCV to the chain cover did stop the leak but then there was smoke from the exhaust. Re routing the feed to the PCV appears to have stopped the smoke. I plugged the chain chest cannister and I make sure the dip stick is pushed well in so there is a decent negative pressure in the crank case. I think the cannister should stuffed with wire wool and mine doesn't have any so maybe this is why the PCV was sucking oil.

Jan T
J Targosz

Oh no the dreaded oil sucking saga!! The archives hold some very very long and interesting stories
Bob Beaumont

Hi P.Peters,
Thanks for your great reply+photo's

Your right in that your top wont fit on later(windup windows) spridgets.
I already have a hardtop and still have no clue who fabricated it.
My top, for 67on spridgets, looks a lot like yours (side roofline, wrap arround window (but not as wide as yours) and the same loop on the inside.
Maybe the designer of my top was inspired by Clifton or use to work for Clifton?
will I ever find out? LOL!!
Think your top, like mine, werent expensive tops in those days hence the what cheap finish






A de Best

same loop and also reinforcement in the side of the top going to the back.
No headlining or anything, just the bare fibre material.





A de Best

My top as a build it yourself kit at 47pound (march 1978)

On Clifford ive not yet found any advertising/brochure on the spridgettop they were selling, lots tho on the mgb gt-top





A de Best

This thread was discussed between 30/11/2022 and 07/12/2022

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.