GT6 Mk1 Coolant capacity

[AidanT]

Can anyone confirm how many litres of water my cooling system should take? I can't find anything for the Mk1 - The handbook I have says 6.5 Litres  - If that's right then I have been running two litres short but don't seem to have any further space to get any more fluid in!

 

I can only find the capacity for Mk111's on the internet and I'm not sure that would be the same

 

Thx

[dougbgt6]

My Haynes doesn't differentiate between 1,2 & 3 and says 6.2 litres. Canley say it's the same radiator for all and it's the same block. Maybe there was a smaller radiator originally which is no longer available?

 

Or, could your heater be blocked up? You wouldn't notice in a GT6 

[Colin Lindsay]

First site I went on the Net - http://www.teglerizer.com/triumphstuff/gt6/GT6specifications.htm - claims 4.5 litres for the MK1.

 

The second - http://www.oocities.org/rotoflex/gt6-oem.htm - claims 6.2 litres or 11 pints for all three models.

 

Otodata listed it as a 2-door convertible sports car… so I ignored them.

 

John Thomason’s ‘Guide to Originality’ lists capacity as 6.5 litres and to be honest I can’t see how they’d miss out on two entire litres, although possibly this smaller capacity is for a car with no heater system fitted? I suspect the radiator was the same for all three models so no smaller version fitted; cooling was marginal enough and if this had been the case we’d see a lot more owners looking for the larger radiator to retrofit earlier models.

 

Aidan - as long as yours isn’t air locked, and the heater is working well (and you have the correct radiator!) - then I’d try to flush it to see if there’s any kind of blockage around the system, particularly around the engine block. HOWEVER - and that’s block capitals as it’s a BIG however: are you sure you had yours totally empty when you refilled it? It’s easy enough to simply drain the radiator, without draining the block and heater as well, so this may account for the two litres already in there.

[Clive]

As Colin points out, the 2 litres is probably in the block, unless you drained that (tap or hex bolt/plug at rear of engine under manifolds)

In fact, there is usually a load of crud in there so no water comes out when you open it, best poked with wire etc and flushed to get it clear.

[AidanT]

Thanks - Drained today and got 4.5 liters out as I was expecting, and have blown air through the heater matrix to ensure that it clear. I will have a look at the plug tomorrow, never actually seen it, but I have seen images so know to look under the manifold around the starter motor area - Will let you know if this is the missing two liters!! 

[Pete Lewis]

cheap way to clean the system is give it a fill with hot water and a good cupful or more of ordinary washing soda, 

 

run it for a few days , and really rinse it out well.  as soda will eat away at the alloy parts   

 

 

it wont remove the build up often found behind the block drain but shifts a lot of unwanted crud.

 

Pete

[Cookie]

The factory workshop manual shows the capacities clearly for all Models of GT6. They are all the same at 11 pints (=6.2 litres in "new money")

 

To be honest wehn draining and re-filling you unilkely to get all the entire old coolant out and the the 11 pints would be from empty.

[AidanT]

Hi. Well the block drain definately is!..BLOCKED. tried everything I can think of but run out of ideas. Anyway got 5.5 litres in so I don't think that's too bad. I will have to see if there's improvement in the temperature in slow moving traffic. Got lots of brown gravy out so with a bit of luck it should be better.

[Pete Lewis]

The last resort is to pull core plug

needs manifold off tomget good access and buy a new one before you start

 

pete

[Clive]

You really MUST get it cleared. If that area is blocked the water flow around the block will be compromised and that is bad news.

Wire coathangers, choke cable bowden cable (throttle cable, etc etc etc) are all useful things to poke about. Once you have got it clear, a comprehensive flush is needed, initially with a hose (and yes, pushed up against the block drain is an important aspect) followed by a chemical clean and reflush before filling with coolant. Without that you are only doing half a job, probably less.

[AidanT]

Now back on this - What chemical clean would you recommend?

 

Thanks

[Clive]

I have used holts speedflush, but I suspect they are all just sodium hydroxide or similar. Most should work, but get as much crud as possible out first.

[AidanT]

Hi. Well back to this now. After being rolling road tuned the car is running hotter. Can you advise what width the wire needs to be to clear the block? I am still struggling to get anything appropriate to clear the blockage.

 

Thx

[AidanT]

Sorry just reread the above. Will try those or similar. How deep do I have to go in before I get to the water gap?

 

Aidan

[Pete Lewis]

3/4"

the jacket is just the other end of the threaded hole at worst you may need to drop the manifold and pull a core plug any old bit of stiffish wire will do nothing special

 

cheap cleaner is two cups of ordinary washing soda powder give it a good flush after a couple of days

 

and repeat

 

you can get hydrochloric acid drain cleaner but dodgy stuff to have spilling around when you drain it

[Gully]

I recently drained my GT6 Mk 3 cooling system via the block drain plug and bottom hose. After replacing the radiator (which now has 50% more cores) it took over 6.5 litres to refill, so most of the coolant will come out!

 

The handbook recommendation for filling to avoid air locks worked well for me:

 

1. Fill the system via the radiator filler until full. Fit rad cap and half fill the expansion bottle.

 

2. Run engine at fast idle for 30 seconds, stop engine and top up system via the radiator filler. Refit cap.

 

3. Run the engine up to normal operating temperature. Stop and allow to cool, then top up expansion bottle until half full.

 

Cheers,

 

Gully