MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

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 MGB Technical - Heat shield

The petrol pipe heat shield that fits at the bottom of the heater box is missing on my Roadster, I intend to fabricate one but not sure exactly what it looks like or how it fits. Would appreciate a picture or two to help. Thanks
Trevor Harvey

I don't think it's important, late cars and even the V8 didn't have one.

But Google AHH8900 and you will get the idea.
paulh4

Thanks Paul, it looks like my one might have done as there is three bolt holes in the edge of the bulkhead where one might have fitted.
Trevor Harvey

Would someone kindly send a picture of one fitted as not sure of where exactly it is attached to the bulkhead. Thanks.
Trevor Harvey

A piece of angle iron 1x1" would do the trick, enough to break the line of sight to the hot bits.
Paul Hollingworth

Trevor, mine is secured using 2 of the 3 front heater box mounting screws, it uses the middle and nearside ones.
R.A Davis

Yes, middle and nearside, on top of the heater flange. I think it's more for supporting the fuel pipe with HS carbs than anything else - it's not shown on Clausagers HIF-equipped cars - which is what the tab with stud is for. Some call it a fuel pipe shield but the pipe is above it, the Parts Catalogue calls it a brake pipe shield but why they need shielding I have no idea, if the brake fluid boils there and not at the calipers then the car is on fire!

paulh4

There you go Trevor, not the best image but they're hard to find of it fitted.

If you're that bored you want to make one I can give you plenty of work on my Midget.


Nigel Atkins

Just noticed the P-clip is bent forwards so the pipe is almost in front of the shield as well as being above it.

paulh4

Paul,
perhaps in your photo the p-clip is fitted up and above the shield instead of down and behind the shield.

In the photo I've put up it's too low-res for me to tell how the p-clip is fitted.
Nigel Atkins

The pics in Clausager show the fuel pipe raised as per Paul's photo.
Cheers,
Charles
Charles9

Trevor, I might have one. I will check tomorrow.

Colin
Colin Parkinson

Charles,
fair enough but is that photo of car as from factory or restored, not that it really matters.

What would the reason be for raising the fuel pipe like that, or protecting the fuel or brake lines at that point.
Nigel Atkins

Nigel,
The fuel pipe is shown raised in several photos of different aged cars.i agree it seems odd. Is the inention to keep it away fom the back of the engine / hot transmission tunnel particularly when the car is stationary?
Cheers,
Charles
Charles9

Nearly every car i've seen with the shield has it fitted like in this pic. but, I like to turn the P clip[ over and run (rebend slightly) the pipe lower down, it ends up about level with the top of the shield which makes it work better and look better

willy

William Revit

As mentioned before IMO it's more of a support than a shield as just after that it connects to the hose to the HS carbs. HIF carbs didn't have it as the pipe goes further round the engine bay and has more supports, so heat is unlikely to be a factor. The V8 fuel pipe has two clips, but on the front of the bulkhead with parts of the engine much closer than the 4-cylinder so in more need of protection, if protection is the purpose of that plate, let alone heat.

Even calling it a brake pipe shield is odd. If it's to protect the pipes against the engine coming back, if a frontal impact pushes the engine back that far you aren't going to need the brakes any more. However HIF cars and the V8 have the brake pipes going over the heater, the V8 has the electric screen washer wiring in it's place.


paulh4

Cheers Charles. I'm never fully convinced that all about British made cars, particular at these times, is fully to do with engineering technical reasons, I think some odd things go on for odd reasons divorced of obvious logic. Work 'practices' can often be odd for odd reasons some even lost with the passing of time.
Nigel Atkins

That’s great, thanks everyone, that’s just what I wanted, I’ll make something up using the info. With this lockdown I’m catching up on a few jobs on the B that I have been intending to do for a while. Trev
Trevor Harvey

My fuel pipe was sitting above the bracket and during a conversation about hot running issues with a friend he suggested it should be at the lower position, as per Willy’s comment I re-positioned it at the lower position, where I think it looks more at home.

Going slightly further of topic, when I replaced all the brake pipes a few years ago, I ran them as per Paul’s picture above the driver’s side bonnet hinge. Having just put them in but not bled them my neighbour told me about incident in a GT, while driving the bonnet catch let go and the bonnet flew up and bent over the roof. It struck me that if this happened the hinge would make a good guillotine, either slicing or at least flattening the brake pipe. As this pipe feeds the servo, it would affect all the brakes. What’s the chance of the bonnet flying up like this? Very small I would think but the thought of not being able to see the road and having no brakes concerned me enough to re-route the pipe below the hinge. Am I being paranoid?
R.A Davis

no
William Revit

Trevor I have this one if you are interested.

Colin




Colin Parkinson

RA, yes the bonnet has been known to fly back if both the latch and the safety catch fail, and yes the hinge does reach the brake pipes before it's gone all the way back. It could just push them out of the way as the original pipes are pretty hard, but there is a P-clip right by the hinge so they would probably be bent at the very least.
paulh4

Bob,
yes you are being paranoid but that doesn't necessarily mean that they're not out to get you.

I've forgotten to push the bonnet down on the locking pin a good few times but the safety catch has always held.

My bonnet is out of line (concours original factory finish) so quite a few times I've thought I've forgotten to engage the locking pin so have pulled over to check to find I had shut proper (that time at least). I've done the same when I thought I've heard some rattle from the boot as I sometimes forget to turn and engage the boot handle too. They've yet to get me on these yet but only time will tell!
Nigel Atkins

This thread was discussed between 30/11/2020 and 05/12/2020

MG MGB Technical index

This thread is from the archives. Join the live MG MGB Technical BBS now