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MG TD TF 1500 - TD Petrol Vaporisation

Does anyone know if there is a proprietary carburettor/ exhaust heat shield on the market please? Twice now I have experienced vaporisation after a run to stop and then restart after 5 minutes or so. Regards, Peter.
P J Wilgoss

Peter,
There are quite a few options out there,, I will do my best to search out the archives and post the various links, Also, a lot of people have had luck with 1) ceramic coating of the exhaust manifold, 2)turning the fuel bowl away from the hot manifold and 3)adding spacers at the carb mounting to stop the migration of heat into the carbies,, OR living with the problem and using the choke for that hot start. Works like a charm..
I'll post more soon,

Steve
Steve Wincze

Steve, thank you for a quick response. Three great ideas, the spacer seems to be the easiest to achieve a result quickly. It seems an obvious answer now. Look forward to the links if and when you can find them.
Regards, Peter.
P J Wilgoss

Found one about turning the fuel bowl away from the heat source,,

http://www2.mg-cars.org.uk/cgi-bin/gen5?runprog=mgbbs&access=&mode=archiveth&subject=8&subjectar=8&thread=2014102809065323802
Steve Wincze

Really Steve has nailed the easiest solution. Just use the choke on restart and put up with a little gasping and bucking for 2 minutes.

You can also raise the bonnet and let it cool off if you are planning on shutting it down and then starting within 15 minutes or so.
Christopher Couper

One thing I have done on some of my cars that suffer from this issue (not my TD for some reason) is to wrap the float bowls with home foam pipe insulation and hold it on with a nylon tie. The second thing is to cut a rubber hose longitudinally and fit it over the metal fuel pipe leading to the fuel pump. All are simple to do, totally reversible and good for a trial test for results.
John Quilter

I purchased a stainless heat shield from Barrie Jones for my TF-1500 and just installed it over the winter. It is a high quality, polished piece that is well made and looks very nice. I will find out this summer how well it works, but expect good things.
Jack Long

The main problem with the TD is not vapor lock before the fuel pump because the pipes are quite far from the exhaust manifold (or check this first)
The problem is often situated between the bowls and the carburetor itself. Therefore insulating spacers between carbs and manifold are efficient. Not only because they are insulator but mainly because they increase the distance from the exhaust manifold.
This is mainly radiated heat

The other cause is the front bowl which is hotter than the rear one because of the warm air flowing from the radiator and fan (you can check this just by touching the bowls).
This is convective heat.

So besides the spacers, I made my own heat screen that solves these two issues. It covers the entire exhaust manifold and the front bowl. If you are patient enough, the chart may be published soon in TT2 magazine.


There is probably another possible improvment but I didnt experiment about it yet.
I think that the front registration plate prevents fresh air from flowing inside the engine compartment.
However few improvment is expected when parking. The engine bay may be cooler just before parking.

Laurent.



LC Laurent31

If your fuel pump is clattering away? Yes or no?
That is due to vaporlock under the pump in the fuel line from the tank. I've measured the air temp at the fuel line, with thermocouple, up to 255F/124C.

If pump is clattering, throw cold water on the vertical fuel line or wrap a wet rag around it, if at all possible, to help recondense fuel back to liquid quicker.

I wrapped some plastic wire loom around ours for insulation.

Vaporlock has been discussed in great length over the years and can be reviewed in the archives.
JRN JIM

Peter, are you sure it's vaporisation?
I went through all the recommendations, including insulation where fuel pipe runs alongside the exhaust on the chassis.
Cause was intermittent failure of the coil.
Mike TD29330
M Lees

Thank you to all the contributors who answered my query. I will now apply these ideas to, hopefully, cure the problem. Cheers for now, Peter.
P J Wilgoss

Here is a photo of the Barrie Jones heat shield installed on my TF.


Jack Long


Brown & Gammons have a very nice carb heat shield P/N GAC1036 47.94bp.

https://www.ukmgparts.com/product/td-midcat-9-td13-exhaust-manifold-exhaust-system-inlet-manifold-air-filters/heatshield-tc-td-tf-gac1036

Jim

James Neel

If the engine compartment is heat soaked as in after a run and then making a quick store stop for 5-15min. A heat shield is of NO value...the entire compartment is hot..including everything above and below the heat shield. Just choke the car..it will fire right up and off you go!
Regards, tom
tm peterson

@tm peterson: I think you and I are the only ones with this mindset. Everybody else wants to fix the problem. :-)
Christopher Couper

I would put "problem" in quotes. Regards, tom
tm peterson

I had this problem last year as the weather got warmer.

I made/installed a heat shield. I chucked the mid '80's Monza 2 pipe POS exhaust and installed a SS factory spec one. I also switched to non-ethanol gas.

Not a hickup since.
MAndrus

Tom & Chris,
If the fuel pump is clattering away like a telegraph key on steroids, it ain't pumping gas, period. You can pull the choke twenty times and it still won't start.
JRN JIM

A heat shield won't fix the fuel pump problem. I suspect you have a bad (failing) fuel pump and/or a restricted fuel line.
Christopher Couper

Hello. I refresh with water between the bowls and carbureter. With a water pump, a reservoir and irrigation pipes. All discrete.
Gabriel Martínez

This thread was discussed between 04/04/2016 and 15/04/2016

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.