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MG MGB Technical - Carb Heat Shield

Has anybody found a replacement for the asbestoes pads behind the heat shield? One of mine is missing and Im getting vapor lock.
JLG Galbreath

I spent ages trying to find something for my car. In the end I gave up on finding anything like an original material and instead used this metal stuff I found. It's steel (but looks like aluminium), about 5 mm thick and oddly patterned. Came in a big sheet about 60cm long by 30 or so wide. Apparently turbo guys use it as a heat shield as it is easily cut and also bendable. I just cut two small rectangles of that and attached them to the shield using the original bend over tabs.

I have no idea if it works yet though since my engine isn't in the car yet :)

I'd have to send you a picture so you can see what it looks like since it is so hard to describe.

Simon
Simon Jansen

I'm in the same boat. When I took my motor out recently I found that the rear portion of the heat shield was cracked about 2/3 from the bottom towards the top and had lost the rear asbestos insert. I was wondering why the rear carb was seeping fuel and I'm also very hopeful that I've finally located that incredibly annoying vibration that only happens at certain rpms.

I did find what appears to be the exact same shield material at my favorite old fashioned hardware store (where people still know stuff about hardware). Unfortunately it only came in a sheet about 40 X 60 inches. It was pretty cheap...about 10-12 bucks but I really don't want all that extra asbestos lying around my garage.

I bought a small muffler repair kit at the auto parts store. This kit has a mat of some kind of fiberglass material rated up to 2300F and some metal mesh to hold it all together. I'm going to rig this matting up to the underside of the metal shield. I should add however, that since my shield was already cracked, I have added in a stainless steel backing plate to bridge the crack. So I've already set a few pop rivets into the metal and I'll be using more rivets to hold the matting in place. Since it's the rear carb it won't be noticable. Maybe not much help for what you're trying to do.

Perhaps a place that sells welding supplies may have some kind of material that's used for table tops or heat-shields where welding is done???
Tony Grasso

When I had this problem, I went to my local "speed shop" and picked up some insulation. Cut it to size, stuck it in place with number 6 machine screws and nuts and it has been working fine for several years. This form of insulation seems to be some form of fiberglass within an aluminum outer covering. Bob Muenchausen had mentioned the use of hot water tank insulation for the same, or similar, purpose. Les
Les Bengtson


Spent ages looking, then Bob M's comment sent me to the local Central Heating store. Found some modern material which looked just like asbestos sheet which is now used in CH boilers. Think the trade name was Mica but could be wrong.

Tony, hope your store didn't sell you asbestos!

Regards,

John
John U

There are many different types of asbestos replacement materials available. You might want to check out the following from a simple Google search:

http://www.adlinsulflex.com/

http://www.pegasusautoracing.com/group.asp?GroupID=HEATBARRIER

http://www.koolmat.com/main.htm

http://www.raceindustry.com/?catid=196
Bob Muenchausen

FYI, I just noticed that Koolmat has material specific to our cars at http://www.koolmat.com/british.shtml
Bob Muenchausen

And yet another ~ http://www.heatshieldproducts.com/
Bob Muenchausen

I replaced the insulation on the heat shield for my '72B with a material that I got at Home Depot. It is in the plumbing department and sold as a barrier for protecting walls and studs while soldering copper pipes. I think the cost was about $15 for a sheet that had enough material to do the entire heat shield (including the middle that did not originally have any insulation). I just pop riveted it in place.

It seems to work fine. I have no vapor lock problems.
glq Greg

Greg:I like the Home Depot idea. That sounds easy to find and install plus being cheap. I'll try that first. Bob: Great sites if I still had my AH 3000 I'd buy that kit from Koolmat. Man that car was HOT! Thnx
JLG Galbreath

I used a material I found in a industrial catalog of Mc Master-Carr. It is used for boiler siding. It is moldable by wetting, glues in with an adhiesive. It is about 1/4" thick and is good for 2000degf.
I got to line the floor boards and transmission tunnel but it work good on the carb heat shield as well. It's a little pricey at $65.00 for 40"X40" sheet. It does work.
E Moore

The number of materials available are many, and some are actually cheap and readily available. The choices are limited more by our creativeness and willingness to step outside of ordinary practice and materials and sources.

I have used a non-asbestos sheet insulation I bought years ago from one of the racing equipment suppliers which has held up remarkably well over many years. On another car I used the same material clad with a layer of aluminum (on the manifold side for heat reflection) from a disposable Aluminum cookie sheet. It too has lasted much longer than I would have expected and both have done at least as well at isolating heat as the original materials seemed to. Perhaps better, as at least these materials did not allow the heat shield itself to become hot enough to burn the paint off as happened with the OE materials.
Bob Muenchausen

I updated my little page of pics. There is a pic of my carbs and heatshield at the bottom of the page.

http://www.asciimation.co.nz/pics

Strange stuff. Looks like tin foil but it is actually steel. I just got it from the local auto parts place.

Simon
Simon Jansen

Simon

Nice site - good detailed photos!

My heatshield had a split, as mentioned in one of the earlier posts. I recognised that it was growing since the resonant frequency of the annoying "buzz" got lower! Solution was a new heat shield from Moss.

Barry
73B
B.J. Quartermaine

I used the Home Depot heat shield material about a year ago. It's very flexible, like a cloth, so I cut some strips of metal to hold it in place and hold the pop rivets. It works as good as the original.
Ken T
Kenneth Thompson

Just remember, not all Home Depots carry the same stuff everywhere or forever. ;-) You might have to go to our competitors in the big Blue Box. But the real point is that you can find suitable materials in unlikely or, at least, un-automotive places. A paradigm shift, to be sure.
Bob Muenchausen

Painted mine with aluminum loaded reflective paint and didn't bother with the insulation c$%p. No boiling, no vapor lock, no worries.

Mike!
mike!

This thread was discussed between 17/09/2004 and 24/09/2004

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