Coolant change

[FTOandTVR]

Has anyone got a how too for doing a coolant change on the Chim?

[kenny chim 4]

Jack the car up on the side where there's a drain nut on the bottom of the radiator and place a basin under it. Remove both the blue pressure cap and the brass nut on the top tank and then undo the drain nut. The coolant will then rush out .

Pour fresh water through the system, to flush, and then refill. Note- it will release (and take) up to 12 litres- maybe more.

[spend]

Never heard of a drain nut before...

I syphon from the swirl tank into a container. Then remove rad bleed screw and syphon from Rad, which just about drains the system completely (and cleanly - I re-use my coolant it costs a lot..) Back flushing the system is good - but then you have to release hoses....

Dave

[kenny chim 4]

Spend, so your radiator doesn't have a release nut at the bottom, but mine does. Many cars have different componants.
Should the O/P have the same as you then I would suggest removing the bottom hose to release the coolant.

Incidently, I would never re-use coolant- especially the blue stuff as it's only good for about two years!

[spend]

kenny chim 4 said:

Spend, so your radiator doesn't have a release nut at the bottom, but mine does. Many cars have different componants.
Should the O/P have the same as you then I would suggest removing the bottom hose to release the coolant.

They do have different components, but I have never seen a rad with a drain valve on a TVR..., you can get anything you wish plumbed in if required. You will still get a very wet arm, undertray and garage floor if you drain by pulling the bottom hose off, & to some extent via your plug wherever it has been fitted in the lower part of the rad.

kenny chim 4 said:

Incidently, I would never re-use coolant- especially the blue stuff as it's only good for about two years!

Modern Coolants are designed to last much longer and are reasonably expensive - not as much as the water wetter, but I am not so wasteful to consider pouring either down the drain If you have a good cooling sytem there is no reason not to use these more advanced additives, if you blow off or have leaks they will probably drain your pockets tho.

Dave

may Allah show you the way....

[GreenV8S]

Spend do you monitor the state of the corrosion inhibitors in your coolant? These alloy engines are very vulnerable to corrosion and will gradually 'use up' the inhibitor, which is why it has to be replaced periodically.

[spend]

Pete, yes... I used to change stats every 6 months & inspect for this very reason. TBH the red + WW seems far more effective, I live in a very hard water area (just used boiled/cooled water) yet all the pipes & internal alloy that I can see is far cleaner than it used to be. The newer coolant seems to be cleaning up the mess that I inherited, I just keep filtering it & then putting it back in. From my point of view it is very satisfactory, but the synth AF is pretty costly ~ but life expectancy of 10 years, after much research I plumped for an Audi variety BTW ~ as is the WW, so you dont want to be replacing them very frequently Not sure re the benefits of the WW, but Joo reckons it helps prevent air locks. I'm firmly on-side of nose up on ramps to refill - but maybe its the WW? certainly I have had no problems refilling.

I would just add that Tims steel pipes would'nt fit my car - so just cleaned up / painted the originals, live to fight another day type thing. No slight intended on ACT Tim ~ there are so many variations its a bit of a mare... The new additives have done a great job of actually improving the interior condition of these pipes - which really surprised me.

Sounds a bit like snake oil - but I just try & think of it like mineral vs synthetic oil I did do a lot ofreading before I started - but must admit a lot went over my head, I guess its a bit of a leap of faith? Bear in mind nearly all new cars are using synth AF & specifying much longer life before changes (there are lots of versions of the AF BTW). I am very happy with the results, and would rec. it no problem.

Dave

[FTOandTVR]

Had a look but couldn't see a drain plug, which is why I asked the question, pulling off the bottom pipe was the next plan, thanks chaps.

[thegman]

duhhh.

ok - just bought my TVR.

Not running hot (well it runs at about 90 in traffic but I here thats normal).

I wanted to check the coolant level rather than do a total flush but reading the manual just confused stupid old me.

So some questions:

- How do I check the level? I can see the expansion tank with the blue screw top and the bleed nut on top of the radiator???
- What would you recommend I top up with? I have some Mobil Antifreeze + Summer coolant from my old car. But wanted your advice.

I am going to take the car in for a service in December - how often should I flush the coolant?

Edited by thegman on Thursday 13th September 10:42

[subhas]

Gents

I have a tvr chimera running very hot. Fans working , both chambers topped up with water.

Needless to say,It’s been sitting for a long time.

It’s dumping water after a short drive and making lots of gurgling sounds. lots of steam coming out.

I don’t have a garage so can’t do road side repairs, and my back is mashed.

Anyone know of a good local mechanic ? ( west london -Chiswick area)

[Belle427]

Air locks are quite common and hard to shift sometimes, have you re checked the fluid level after it cools tight down?

[TarquinMX5]

No idea about a mechanic but most (Chimaeras, not mechanics) seem to prefer the level in the expansion tank to be approx 1/3 - 1/2 full when cold. If over, can spew it out when hot; also not unknown for the inlet/outlet pipe on bottom of expansion tank to be blocked with 'crud', which doesn't help.

[bobfather]

If you're topping up it's no surprise that it's dumping water, the expansion pot is too small for the quantity of coolant so it needs a lot of room for expansion. Top up to 1/3 when cold, any more and you risk expansion beyond the headspace in the expansion pot.

If you are at 1/3 cold and it's still throwing coolant out then the highest probability is that the expansion pot has, at some point boiled over and then sat too low during cool down. Too low will mean the system will draw the pot dry as it cools and thereby draw in a slug of air. Because of the low position of the expansion pot it is not natural for air to go back to the pot. Air in the system causes hot spots and localised boiling. That boiling throws more coolant out. You need to ensure the system is purged of air. Air gathers in the swirl pot and that's where you need to bleed the system. Maintain 1/3 cold level and bleed at the swirl pot, manipulating the top hose helps to push air into the swirl pot. Keep going through several heat cycles until swirl pot air is minimal.

If you over fill the expansion pot you trigger boil over and subsequent air ingress. Once this has happened the only solution is to go through the process above

[Steve_D]

many cars like the coolant level in the expansion pot even lower than 1/3 when cold.
Other issues are failing to bleed the air from the radiator and second the heater likes to keep an air lock so you must have it set fully hot and often repeated revving of the engine will clear it.

Steve

[Loubaruch]

As Steve says, My Griffith 500 also prefers the level in the expansion tank to be about 1" from the bottom, if filled 1/3 or 1/2 way it will just eject it. Its been happy at this level for 20 years so guess its OK.