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MG TD TF 1500 - TD Heat Shield

Does anyone have experiences of running a TD before and after fitting a heat shield. I have been running my TD for a year or so now, with no heat shield, and have had no apparent problems. The previous owner also thought that it was not nessesary, or one would have been fitted.
Henry

Henry - We ran our TD for years without a heat shield and never experienced a bit of trouble with vapor locking. It was only after restoring the car that I started experiencing vapor lock and finally installed a heat shield. I have always felt that the problem came from the reformulated fuel that came into being during the time I woas working on the restoration (restoration took me 5 1/2 years). The other thing that may be contributing to the problem is more heat in the engine compartment. I had the exhaust manifold aluminized, so perhaps it is radiating more heat than before, or perhaps I realigned the grill slats and have reduced the amount of air getting through the radiator (I don't remember having done this, but...). I do know other TD drivers who have not experienced any vapor lock problems and would certainly not recommend installing a heat shield unless someone was having a problem. Cheers - Dave
David DuBois

vapor lock not a problem but general heat is. I tend to agree with Dave and the fuel issue. That was the only element that changed on my car over a period when it started to run hot.

Having said that even with the outside air temp at 105 F and the radiator about the same I do not experience vapor locks at sea level. Not sure what the story would be at 5000 feet or above.
Chris Couper

I am convinced that heat shields make matters worse. The problem, if you have any, is that the fan mounted on the water pump directs warm air to the front carburettor. One cure suggested to me by the late Don Jackson, an expert of SU products, would be to put a shield ahead of the front carburettor to deviate the air from the fan. I have never done that, but I have mounted temperature sensors on the carburettor bowls connected to a digital thermometer and indeed the front one is about 5 degrees C warmer than the one at the back.

Denis Baggi
Denis L. Baggi

We have never had vaporisation problems on the TD or TF. THe TF is more prone to heating due the body being tighter around the engine. Perhaps the answer is to drive faster which means more air entering the engine bay and the fuel running through the carbs at a rate where it doesn vaporise.
Bob Marshall

Wondering if the fuel line running parallel to the exhaust along the chassis might have anything to do with it too...
Will

I think the problem is more related to the radiator slats. Lokks at an original grill and then at a reproduction. The air flow is dramatically different in the repro grills or one that has been modified, compared to the originals.
Revise the slats and open them up--much better
airflow = less vapor lock and overheating problems.
Cheers, Rob
Rob Silverman

When driving my TD in our summer in heat of 100 degrees fh and over, then parking, the petrol in the float bowls boiled. I then had to wait for it to cool to get started. I have heard of people packing ice around them to get going. However I made shields to fit between the bowls and the manifold and I have not had any trouble since.
Dave Broadbridge

Two years ago I had vapor-lock problems with my TF1500.
At that time I also noticed that the operating temp. was somewhat always to the "high side" of the gauge.
I had my exhaust manifold "JET-HOT" coated and have not had a problem since. The process treats not just the outside of the part...but the inside as well, making for a very "slippery" exhaust. When the hot air leaves the engine quicker the operating temp is lowered so the "heat" problems go away. There was an earlier thread where this was disscused in detail. (Operating Temp?...I think was the thread tittle). I still feel this was the smartest $100.00 I ever spent on my car!
Cheers,
David #A1 55 TF1500
David Sheward

I will ocassionally suffer vapor locking when parking on a hot day or when I have been running a while and the engine is hot. If I try to start the car after less than 1/2 hour after stopping, I will experience a bit of vapor lock - car sputtering, etc. - which will go away after a minute or so of idling. If I wait longer than 1/2 hour or so before restarting, generally no problem.

I have found it much easier to live with this little quirk than install a heat shield to prevent it.

Larry
Larry Thompson

Just an idea re trapped heat... staring at the bonnet design (sans louvres at top) - would it help to just pop the RHS bonnet when parking on a hot day?

Curiously never had fuel vaporisation problems before with a Morgan +4 (louvred top) nor MGTC (more room)... although I hear a lot of the TF guys do suffer.
Will

Sounds like same problem I was having season before last!
I would go get my friends trailor get the car home and she would fire right up.
It was driving me nuts. I finally noticed that the carbs were getting very warm.
Little hint...at 1 point I was stalled in front of a drug store (for my scheduled
1/2 hour sit!)....went in and purchased one of those "snap n' cold pac's"...
put it on the carbs and she fired right up. Since then I keep 1 in the tool kit.
You might want to look at the fuel lines also...mine had been replaced with
rubber...going back to the stainless steel mesh helped a bit.
Check out the "Jet-Hot" for the exhaust manifold. I really feel this is
what cured mine! (Got rid of a really ugly manifold as well!) The change was
so dramatic I thought my temp gauge was not working...20/30 degree change.
When I had the TF up to John Twist shop last year he and I talked about this
a bit...he has been doing this to some of the "T"'s up there as well. For the
$100.00 it cost ...really feel it was worth it. I was over to visit my TF at the
shop the other day and my buddy gave me an electric fan that I am also going
to install in front of the radiator for a little extra air flow. Going to put that one
on a switch so I can have control over it.
David Sheward

Will - re. "Wondering if the fuel line running parallel to the exhaust along the chassis might have anything to do with it too..." At least in my case that is not the problem or even contributing to it. One of the things I first tried was insulating the entire fule line run, to no avail. Dave
David DuBois

Have had a few of you ask so going to post this.
First let me say ..I am not on comission with them but have been very pleased with the results. Their turn around was quick. Only bad thing I could say is that they said they would send me (and LVB who 1st told me about this) a T-shirt and never did! No biggie and this really seems to have worked. They can also do a colour treatment that looks like it would be very close to the orginal "white". (Mine is "sterling" it was cheaper and looks like polished alum).
Here is their site info....ask them were those "T" shirts are for those "T" guys...Larry & David!
http://www.jet-hot.com/
Cheers,
David #A1 55 TF1500
David Sheward

My 53 TD typically experiences some form of vapor lock after shuting down for a fuel or lunch stop on very hot days. Don't understand exactly why, but liberal use of the choke has always cured the problem enough to drive away. Have never experienced the problem while driving, only after a stop.
Bill
Bill Cole

Chaps, I have suffered vapour lock occasionally with my TF1250 - it always seems to happen at the least convenient time. It seems to be an idiosyncracy of the T - some never suffer, even in really hot weather, and others do even in much cooler weather. So I fitted a B&G heat shield - it was a bit fiddly, as I had to ream the holes a bit to get it to fit correctly. This has mainly cured the problem - it has happened once since then, but this was at a time when the car was not running very well anyway - typical T problem, carbs leaking at the cork seals and thus running too rich. It seems a sensible modification if your T is one that is prone to the problem, but I fully understand those that won't fit them. I have seen reference to heatshields being available as an after-sales fitment, but have never seen a car that was originally fitted with one - AB.
Adrian Bennett

Here's another thought. My original fuel pump quits when very hot and gives all the indications of vapor lock. I know that is not the problem as I have one of the "solid state" fuel pumps in series with the original and can switch to it via an under-dash switch. The problem goes away immediately, and have never experienced it when using the second pump (except after gas stops). Your problem may simply be your fuel pump. Buy a replacement (about $30 at Pep Boys), temporarily hook it in, and I'll bet your problem goes away. Bill
Bill Cole

I'm not sure if this is a similar problem. Took the TD on a trip to Gold country, in California. Temperatures into the high 90s and altitudes 3-4000 Ft. Car ran fine, but at each stop the idle dropped to 4- 500 RPM and the engine stalled if I didn't fiddle with the accelerator. Starting with a cold engine, idle speed was 800+ and no problems.
Why the slower idle at temperature and altitude?
Should I just increase the idle for the trip?
Andy Moyce
52 TD
Andy Moyce

This thread was discussed between 04/07/2002 and 23/07/2002

MG TD TF 1500 index

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