View Full Version : Photos of My 2500M's Engine and Radiator

06-10-2007, 01:39 AM
I took these (https://invite.filmloop.com/x?oWLqQuAIwnDw0TaNpG11pH5E3JE5WCWj) photos of the engine and radiator in my '73 2500M.

Some questions:

Take a look at how the throttle cable is routed over the valve cover. It's wearing a groove in the cover the way it's routed. Is this how the factory routed it? I doubt it.

Is the radiator the original? If not, any idea what brand it is? Check out the red plastic fan blade. Is it stock?

Is the small oil cooler mounted in front of the radiator original? I've been having overheating problems when idling for long periods of time. I want to install an electric fan. Any recommendations on the fan installation, given the size of my radiator and that metal square bar directly behind it which is blocking the engine fan.?

The cable attached to the heater valve (see photo) seems to be stuck. I'm unable to push or pull the knob under the dash. Looks like the cable should open and close this valve and controls coolant flow to a heater core, correct?

What's the strange looking fabric wrapped around my exhaust manifold?

Anything under the hood look changed from stock TVR configuration?


06-10-2007, 06:03 AM
Hi,although I am not that familiar with the 2500M,genarally speaking- the throttle cable seems forced ie the whole cable seems too short,the outer cable looks too short and believe it should at least reach the bracket attached to the rocker cover,which seems to be non original.The cable for the heater valve is obviously being forced down by the trunking that passes behind the engine as you can see the outer cable bent downwards.If you disconnect the cable from the valve and then try to move the heater knob you will be able to tell whether the cable is seized or the valve itself-if both move,lubricate the cable and re route it so the cable runs with smooth curves.As I say not being that familiar with the 2500M I would hazard a guess that there should be some kind of shroud or cowl from radiator to surround the fan -as fan is small and set so far back from rad not really drawing air through rad at a standstill.The material that is wrapped round the manifold is used as a heat shield to protect surrounding parts from the manifold heat.

06-10-2007, 10:25 AM
Thanks Mike. I'll check the heater cable. Agree it's definitely being stressed. The spare wheel originally rested flat on top of the radiator and likely served as a sort of shroud for the fan. Thanks again for the info.

06-10-2007, 03:38 PM
I'd say that your radiator is definitely not stock. It appears to be much taller than stock. That's why they had to cut the spare tire mount off to make it fit. You can see in your photo #7 where the two tubes of the spare tire mount were welded. Here's a link to a photo of what the original probably looked like. https://www.olenik.com/tvr/as_purchased/stripdown/fansy.jpg The car that I owned, 3275TM had that same arrangement of electric fans and mounting configuration. Also shown here: https://www.olenik.com/tvr/catalog.pl?page=2.46
Your red fan is the stock TR6 unit, but, I don't believe the TVR came with it. Just too far away to do any good. You should add one large or two small electric fans.
Your throttle connection doesn't look stock either. Both my previous '74 2500M and my current '71 2500 had/have the same setup where the throttle cable comes in around the back between the firewall and the valve cover, and then underneath the intake manifold to the stock TR6 linkage setup. This converts a rearward pull by the cable to a pivoting bracket that pulls a rod downward. The rod is connected to the throttle shaft and rotates the shaft, See the enlarged view in the lower right box in the following diagram https://www.olenik.com/tvr/catalog.pl?page=1.8
That being said, I found a picture of a similar setup to yours, although it looks possibly aftermarket also: https://www.midlifeclassics.com/images/tvr73/Dsc02467.jpg
The material on the exhaust is a thermal wrap product, like this, https://store.summitracing.com/egnsearch.asp?N=400356+302241&autoview=sku
which a lot of people use to try to reduce underhood heat. I haven't used it.
The hoses are all replaced. The accordion type hoses are generic substitutes. It appears that the metal parts of the cooling system are also replaced or have been removed and chromed. The valve cover is aftermarket, but everyone goes with the cooler looking cast aluminum valve cover at some point.
Other than the replaced radiator and missing spare tire, it has a pretty much stock looking appearance with normal replacements.

06-10-2007, 07:35 PM
First of all, thanks for the photos. The radiator in your car is definitely NOT stock fitment, it is about twice as tall as the factory unit, over which the spare tire was mounted. The throttle cable installation is also not original. The red plastic fan was fitted to some 2500Ms but you should also have two electric cooling fans up front.
I think the other questions have been suitabley answered.


06-11-2007, 02:33 AM
Thanks for the info guys. I've ordered two 9" electric fans for the cooling problem. Sounds like the original fans were tossed when the radiator was replaced.

Marshall, do you have the parts I'd need to change the throttle cable installation back to original?

Oh, didn't get an answer on the separate oil cooler. Is it original from the factory?


06-12-2007, 07:46 AM
My 77 2500M has the red fan. However, it has a radiator shroud going from the radiator to the fan to more effectively pull the air through the radiator.


06-12-2007, 05:29 PM
The parts book does not show an oil cooler as standard fitment for the 2500M. It lists it only for the 3-litre Turbo.


06-13-2007, 02:09 AM
Thanks for the info Marshall. I've ordered a pair of electric fans and will install them soon. Can't wait to drive the TVR without worries of overheating. Especially in the stop and go traffic here in San Francisco.


06-19-2007, 11:53 AM
The 73 TVR had a throttle cable similar to what is seen in your pictures. However it was longer. Yours looks line someone adapted a brake cable from a bicycle. I'm not sure of the proper name for this type of cable. I call them a "captured" cable. The idea is to run the cable through a sleeve. You can anchor the sleeve at both ends to contain the movement of the sleeve while routing the cable through various bends. It is a very convenient way to get around having to design and develop a complete mechanical linkage.
later TVR M series cars came will a bell crank in the center under the carbs. The cable came into the bell crank from behind the engine. this was a cleaner installation which worked much better than the original setup.
The valve cover on your engine is also an after market piece. The original cover was the standard TR6 piece.
Your original radiator was replaced by something larger. The original would be approximately 9" tall and 20 some inches wide. I believe they were 4 rows deep. the spare tire was mounted on a bracket that was made of the same square tubing used on the chassis. It was mounted over the radiator and fan angling downward from rear to front.
The fan as you see it is correct. I can't say for certain that the red fan was used. i would have to see if I have any pictures of my '73. As someone commented above the fans was nor very effectine. I believe the spare tire was supposed to help duct the air through the radiator.
I never mounted my spare tire under the hood. One reason was that I ran slightly oversized tires. The hood would not close with the larger tire. I made up some ductwork from galvanised sheet metal to help channel the air. I also ran 2 electric fans in front of the radiator. At the time there were not many choices for electric fans. Mine came from 2 Simcas, an old french car that I think is no longer produced. The fans were operated by a toggle switch on the dash.
When I get around to restoring my '74 M I will cut out the spare tire bracket and replace the original radiator with something larger. i will also install an electric fan and remove the crank fan.
A little trivia for TVR M enthusiasts. TVRs were exempt from some of US the crash test requirements because they were such a small company. (The large rubber chunks on the '74- '76 TR6 were the result of having to meet the 5 MPH bumper crash requirements.) There was a test where they crashed the cars into a wall at something around 20 to maybe 25 or 30 MPH. The TVR M was the only car tested that was able to be steered after this test. This was attributed to the spare tire being mounted up front. Although the bonnet was trashed, the tire absorbed enough of the impact and the mounting bracket was strong enough that the steering remained intact.

Additional information; I thought about this later in the day. My '73 did have some sort of electric fan or fans in front of the radiator when I bought it. (It was used) The fans were supposed to be controlled by temperature sensor that was pressed into one radiator tank. When I bought the in 1977 car the fans were already shot. I went for a drive one evening. When I pulled into the parking lot the temp was already getting high. As the temp and pressure after I shut it down the temp sensor blew out of the radiator with a pop followes by the sound of rushing water. I removed the fans, soldered a patch over the hole where the sensor mounted in the tank and installed the Simca fans.