Jump to content

Expansion Bottle TR4


Recommended Posts

I should also add that I never had any problems with the standard system on my previous TR4A in 3-4 years.

That being the case, it would seem that the system is suspect in some area and prone to throwing out water, but not necessarily so.

 

Any theories on this? The suggestion of hot spots at the back of the block where circulation may be lower seems logical - if steam forms locally, then the volume of water in the system expands and it gets thrown out of the overflow pipe.

 

Any other theories? I'm no engineer - I really don't want to fit an expansion tank in my TR4 restoration but neither do I want to have to top up all the time. Neither do I want the temperature sensor for the electric fan, at the top of the radiator, to run dry. I'm having a fairly highly-tuned road-going engine, so there will be a lot more heat generated than with a standard engine, so if local hot-spots are the cause, I'm more than likely to suffer the problem.

Link to post
Share on other sites

Don't fit the temperature sensor at the top of the rad. It is not a good place. The ideal is halfway down which is rather difficult unless you were to use a cross flow radiator.

 

This is why it is possible to buy the metal pipe with a boss for a thermo switch welded on where it is!

 

David

Edited by david ferry
Link to post
Share on other sites
  • 1 month later...

What all TRs need (but especially the TR4, where the size of radiator is not really adequate for an engine of over 2 litres) is a sealed system which will maintain coolant in ALL parts of the system, including the thermostat housing and the top of the radiator, at ALL times. Why Triumph failed to do this on the TR4A (when an overflow bottle was provided) is a mystery! I installed a sealed system, incorporating a header tank, in 1995 and described the operation in TRaction 156 (and I assume this will be on the Technicalities CD, too). It has worked perfectly from day one, and, once it has expelled the excess from the system on initial expansion, there is no loss of coolant whatsoever, even though the coolant temperature gets well above "normal" in very hot weather (such as we seem to have had for the International Weekends in recent times). When cold, the coolant sits about halfway up the header tank. By the way, because it is a sealed system, the header tank does NOT have to be above the top of the radiator, you can place it wherever you like. In my case, it sits on the right-side inner wing, in front of the foremost carburettor's float chamber and over the top of the spring turret, with its filler inside the bonnet bulge (use blu-tak to check positioning so as to ensure adequate clearance!).

 

To improve cooling, you could add Water Wetter, or use Forlife - this is a product of which Dr Michael Bingley is full of praise, as he tells me it shifts heat faster than anti-freeze and keeps all the internal metalwork in pristine condition. But ... make sure you get all the loose rust and anti-freeze out of the system and ensure all the hoses are in good nick before installing Forlife, as it is very searching (i.e. gets out more easily than antifreeze) and more expensive than anti-freeze. Forlife is used neat - i.e. you do NOT mix it with anything else. I don't know whether Forlife is still available - try the internet.

 

If you have a Kenlowe Fan, I suggest you abandon the use of the capillary switch and install a thermostatic switch in the metal pipe which returns water from the radiator to the engine block - that way, you will avoid the weeping that almost always occurs at the point where the capillary enters the top hose. You can get the parts from Revington and (I believe) Moss.

Link to post
Share on other sites

Ian,

 

I don't have access to TRaction 156 (not kept it for various reasons). Are you able to somehow post a copy of the article on here, or email it to me?

 

I am in the process of building my rally car and any tested modifications for this would be most welcome.

 

Did Neil Revington supply all of the required parts?

 

Regards

 

David

Link to post
Share on other sites
Anybody got a 4a with a working expansion bottle/ rad system ?

 

Hi Mike,

My 4A has the standard system, never had a problem, I get new rad caps from local Halfords every couple of years..(check they have the upper seal that allows the syphon system to work)... no probs......... same system at a higher pressure works on my 2.5Pi saloon........ it's the condition of the upper seal that's the key to working properly.

Cheers,

Rob

 

 

Hi Rob

 

Got my expansion bottle fitted now, do you have a part number for the Rad Cap or do you just re-invent the wheel every two years at your local Halfords?

 

My local store is run my knuckle draggers and I can't imagine them even knowing what a TR4 is as the car park is full of Nova's and Corsa's running 200 decibels and about 59bhp <_<

Link to post
Share on other sites
Ian,

 

I don't have access to TRaction 156 (not kept it for various reasons). Are you able to somehow post a copy of the article on here, or email it to me?

 

I am in the process of building my rally car and any tested modifications for this would be most welcome.

 

Did Neil Revington supply all of the required parts?

 

Regards

 

David

 

David - Section B19 on the Technicalities CD (and if you haven't kept that, well .... ) covers both the Header Tank and the installation of baffles to stop the air going round the side of the radiator instead of through the matrix (the TR4 radiator is not as wide as the ducting which funnels the air to it!). If you are really desperate, e-mail me and I'll send the text of the articles - my address is inside the rear of TRaction, where you will find all the mug shots.

Ian Cornish

Link to post
Share on other sites

Hi Mike,

Sorry not to reply sooner but I've beeen away and only just seen this.... I usually just rummage around in the boxes on the shelves untill I find the right looking cap with the 7lbs release pressure, however I remembered that I have a couple of spares for the cars in the garage and have just found the TR one....... the Halfords No. is HRC604...... just check that it has the upper sealing ring, they are sometimes just loose in the box and get lost.

Good luck, cheers , Rob

Link to post
Share on other sites
Hi Mike,

Sorry not to reply sooner but I've beeen away and only just seen this.... I usually just rummage around in the boxes on the shelves untill I find the right looking cap with the 7lbs release pressure, however I remembered that I have a couple of spares for the cars in the garage and have just found the TR one....... the Halfords No. is HRC604...... just check that it has the upper sealing ring, they are sometimes just loose in the box and get lost.

Good luck, cheers , Rob

 

 

Excellent, thanks Rob :P

 

Just remind me, does it work with a standard radiator neck, or is the 4a different ?

Link to post
Share on other sites

As far as I know that's correct, my rad is the one that was in the car when I bought it in 1969 (tho' it was recored by Serk about 18 years ago)........ along time ago I had the feeling that rads left dry out of cars during rebuilding work seemed to spring leaks when put back in service...... now whenever I take one of my rads out I put bungs in the holes and fill them with antifreeze and put the cap back on............ seems to work!!

Cheers Rob

Link to post
Share on other sites
  • 3 months later...
I fitted one to my 4 this year immediately prior to 3 weeks spent touring Italy in the height of the summer. This too woks perfectly and is a great improvement. Didn't loose a drop and can check water level at a glance.

 

Paul.

 

 

Paul (all)

 

Quick update

 

Expansion bottle is now fitted and after the hot Easter weekend I can report, working perfectly (after I modified it) :rolleyes:

 

As fitted, it used the existing (old) overflow hose which was now too short so two things happend. The tube didn't reach the bottom of the bottle so sucked air not coolant untill half full then it started to work but stopped when half empty. Also hot coolent entered the bottle above the water line as superheated steam/water and would then blow out ot the breather hole and made a mess of the under bonnet which caused concern until worked out.

 

Easy fix, down to B&Q, buy 0ne metre of plastic hose, cut to length, 'V' the bottom to avoid any vacum traps and fit.

 

It really is a very simple idea and works well if fitted and maintained, but one that has failed over time as seals and hoses deterated

 

It really does work, so do it (today) as they say its going to be a long hot summer !! B)

Link to post
Share on other sites

This topic has been covered many times, and a number of misunderstandings have featured in the correspondance.

 

First, all radiator caps are double acting. They have to be otherwise one would have a vacuum in the cooling system when the engine cools down. If you don't believe me, remove your radiator cap and gently lever up the central portion - you will find it lifts and is spring loaded, so that it allows fluid past when the pressure differential is in its favour.

 

Second. The overspill bottle on the TR4A works as designed (it does on mine anyway). The key is to position the overflow pipe from the radiator filler such that it reaches almost to the bottom of the spill bottle and that there is about 1 inch of coolant in the bottom of the bottle, covering the end of the tube, so that when the engine cools all the coolant that has been displaced into the bottle is sucked back into the radiator.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.