Bleeding water system

[Tegriffic]

So when I recently removed the plenum cover to replace fuel hoses, I undid and removed the two water hoses to the throttle body. In hindsight maybe I didn’t need to but I did so I’ve probably introduced some air there. The Steve Heath process for bleeding is via the radiator but there’s no mention of raising the front of the car. Now given the throttle body / plenum is higher than the radiator, am I going to need to raise the front so the radiator is higher than the plenum before bleeding ? I ask this because I’d expect the air lock to sit at the highest point and stay in the throttle body - Or will the water flow be strong enough to shift any air there so I don’t need to raise it ?

Thanks.

[Pagey430]

method I use is from v8d -

- fill expansion tank
- remove small Hose in manifold behind coolant thermostat
- lips to expansion tank and blow gently until coolant is expelled from Hose barb on manifold (top up coolant if needed before it empties)
- top up expansion tank so that coolant expelled from the Hose barb without blowing
- refit small Hose
- top up expansion tank if needed
- run up to temp
- allow to cool and top up expansion tank if needed

hope it helps...

John

[blaze_away]

Another way, always worked for me this one.

Remove plug in the top of the swirl pot. Screw on a large funnel.
Start the car an allow it to reach full operating temperature.
Turn heater controls to hot.
Fill the funnel with water and keep topping the funnel up as water is drawn in and air is burped out.
Continue to monitor until no more air burps.
Remove funnel and screw in the plug
Jib done.

[QBee]

Me too.

[Tyre Smoke]

Blaze away's system works well.

My Chimaera would overheat if left ticking over for more than five minutes. I removed the bottom rad hose, swirl tank plug and reverse flushed it all with a hose, then refilled using the above method. By far the easiest and no hassle at all since.

[Tegriffic]

Thanks.

[QBee]

I can't take credit for the method - It's how Mat Smith, TVR expert and racer, told me to do it.
And after 10 years and 47,000 miles of his expert help, I can confirm that he knows everything there is to know about TVRs.

[gavgavgav]

me too! - and just to add, mine isn't even connected as the pipes are disconnected and blocked off with a bolt in them and a jubilee clip, I had assumed it was done from the factory as we probably don't need the throttle heaters, or has mine been monkeyed with?

[Classic Chim]

Raising the nose is never a bad idea and does assist in forcing air from the heater matrix area as does undoing the small bleed hose situated on top of the inlet manifold on the L/H side.
This is good to do as you fill the system.

Set heater controls to hot.
If filling from empty I usually undo bleed screw in top of radiator until water flows from that outlet and nip up the screw then leaving inlet manifold bleed screw open continue to fill system vis swirl pot until water flows from from that outlet and nip it up.
From there using the same jug system as every other Tvr owner/ mechanic I fill that jug just enough for air to be expelled from the swirl pot via the jug and replaced with coolant from said jug.
I usually still squeeze rad hoses and Rev the engine upto 4000 revs as I’m doing this to aide air removal.
When you have no more air in the system the water in the jug should remain at a stable level.
Remove and tighten swirl pot bung/bolt.

Warm upto temperature ensuring you hear fans come on/off a few times and temps are consistent.
Ideally leave overnight to fully cool and check level via swirl pot bung. Top up if necessary ( it’s known that some cars including my late car the system settles to about an inch below the top of swirl pot ) I find if I top up swirl pot to full it simply finds its way into the expansion bottle so if it’s constantly about an inch or so from the top of the swirl pot when checked when cold it’s full.
If it has an expansion bottle that bottle should show about 1/3 full when coolant is cool so check it before and after filling system and Never let it run dry as that will reintroduce air into the system.
1/3 full allows space in that bottle to allow the water to expand and enter the bottle on a particularly hot day, as the coolant cools down that same coolant gets drawn back into the system via the expansion bottle.
So keep it 1/3 full when cold and it can do its job.