Bleeding the cooling system
Discussion
Get the front high, jack or ramps, bleed the rad first, squeeze the hoses till you're blue in the face, try letting air out the throttle heater pipes (the blanked off ones). Run the car for a few minutes so the pump has chance to push stuff around, and then repeat as above.
I'm lucky I seem to be able to fill it cold and not have to touch it using my magic method
then again the serpers with expansion tanks do seem to a bit more fussy than my uncomplicated old outdated bus 
I'm lucky I seem to be able to fill it cold and not have to touch it using my magic method
then again the serpers with expansion tanks do seem to a bit more fussy than my uncomplicated old outdated bus spend said:
Get the front high, jack or ramps, bleed the rad first, squeeze the hoses till you're blue in the face, try letting air out the throttle heater pipes (the blanked off ones). Run the car for a few minutes so the pump has chance to push stuff around, and then repeat as above.
I used spends' technique a while ago and have had no trouble at all with my serp since. It got rid of all the "gurgling" noises too. It's the "squeeze the hoses" bit that makes a difference IMHO. Just when you think you've done it enough, do it again after running the car for a very short time and you'll most likely find some more air bubbling around the system.Just to clarify a couple of things, as I bled mine a couple of weeks ago after a flush/fill and still not sure about it.
How do you bleed it?????????. Book says remove bleed plug completeley (whilst engine off) and fill....fair enough, but how do you continue to bleed with the engine running?....which you inevitably have to.
It says DON'T partially undo bleed screw as you'll draw in air................yet this is exactly the method I use on the Caterham fitted with the same facility............jack the front up, crack the bleeder a turn or two and wait for the bubbles to stop.
Now am I mis reading the handbook here or is this the correct method?
Cheers,
Kenny
How do you bleed it?????????. Book says remove bleed plug completeley (whilst engine off) and fill....fair enough, but how do you continue to bleed with the engine running?....which you inevitably have to.
It says DON'T partially undo bleed screw as you'll draw in air................yet this is exactly the method I use on the Caterham fitted with the same facility............jack the front up, crack the bleeder a turn or two and wait for the bubbles to stop.
Now am I mis reading the handbook here or is this the correct method?
Cheers,
Kenny
You only have the swirl pot bleed screw on the serp engines earlier cars have the expansion cap on the swirl tank (and no other expansion tank). I think generally when referring to the bleed screw most will refer to the swirl tank brass plug as the bleed screw ( sheer weight of numbers of serp cars;) ) but not the rad bleed - they will likely just mention bleed the rad when talking about that screw.
It's like mastering foreign languages sometimes
It's like mastering foreign languages sometimes
So on my 1998 car which bleeding screw is the bleeding screw
. The bleeding thing on top of the swirl pot is just a bleeding cap surely and not for bleeding. Now that little bleeding thing on the corner of the rad just has to be the bleeding bleeder.......It's getting too bleeding complicated this is
. The bleeding thing on top of the swirl pot is just a bleeding cap surely and not for bleeding. Now that little bleeding thing on the corner of the rad just has to be the bleeding bleeder.......It's getting too bleeding complicated this isUsing technical language, on a'98 car the radiator has a "bleed screw", the swirl pot has a "big brass screw" and the expansion tank has "spring-loaded VW wotsit cap".
Hope that sorts out the terminology once and for all.
Personally, I fill the thing through the swirl pot, plonk a few inches into the bottom of the expansion tank, seal the expansion tank, bleed the radiator, top up the swirl pot, bleed the radiator, top up the swirl pot, etc, until the radiator is no longer bleeding air or bubbles, then seal the two screws, squeeze the hoses, turn the engine over a bit, bleed the rad, top up the swirl pot, bleed the rad, top up the swirl pot, squeeze the hoses, turn over the engine, and repeat until I get thoroughly bored. All with the heater matrix open of course.
By the way, this doesn't get rid of all of the air.
Hope that sorts out the terminology once and for all.
Personally, I fill the thing through the swirl pot, plonk a few inches into the bottom of the expansion tank, seal the expansion tank, bleed the radiator, top up the swirl pot, bleed the radiator, top up the swirl pot, etc, until the radiator is no longer bleeding air or bubbles, then seal the two screws, squeeze the hoses, turn the engine over a bit, bleed the rad, top up the swirl pot, bleed the rad, top up the swirl pot, squeeze the hoses, turn over the engine, and repeat until I get thoroughly bored. All with the heater matrix open of course.
By the way, this doesn't get rid of all of the air.
ATG, is that with the bleed on the rad removed or just undone a couple of turns. With it out completely and engine running it just chuckes out everything you've put in and the Pink a/feeze aint cheap.
Also I found doing it on my own a pain as when the level in swirl pot drops below outlets it takes more air in..tried with a hose in it but that was a failure too.
Thanks,
Kenny
Also I found doing it on my own a pain as when the level in swirl pot drops below outlets it takes more air in..tried with a hose in it but that was a failure too.
Thanks,
Kenny
If I was you lot I'd be tempted to install a LR heater pipe with the bleed screw up by the plenum Thats why I think of the swirl tank as 'the' bleed screw BTW as it seems to be TVR's logical adaptation of the LR system to me
IMHO rad should only need to bled once on refilling (unless you have let more air in...) and the higher point will collect any trapped air as it comes out.
You know the cerb stat arrangement is much better I think, as the stat at the top of the engine seems to be a bottleneck for air as well as the poor circ before the stat opens. LR did similar to the cerb remote stat in the later cars as well.
Thats why I think of the swirl tank as 'the' bleed screw BTW as it seems to be TVR's logical adaptation of the LR system to me IMHO rad should only need to bled once on refilling (unless you have let more air in...) and the higher point will collect any trapped air as it comes out.
You know the cerb stat arrangement is much better I think, as the stat at the top of the engine seems to be a bottleneck for air as well as the poor circ before the stat opens. LR did similar to the cerb remote stat in the later cars as well.
kenny.R400 said:
ATG, is that with the bleed on the rad removed or just undone a couple of turns. With it out completely and engine running it just chuckes out everything you've put in and the Pink a/feeze aint cheap.
Also I found doing it on my own a pain as when the level in swirl pot drops below outlets it takes more air in..tried with a hose in it but that was a failure too.
Thanks,
Kenny
Blimey ... someone asking me a serious question ... must be desperate Also I found doing it on my own a pain as when the level in swirl pot drops below outlets it takes more air in..tried with a hose in it but that was a failure too.
Thanks,
Kenny
When I turn the engine over, everything is sealed. I'm not looking for the engine to force air out, just shift it around so that some more of it collects in the rad and the swirl pot. Once engine is off, then I top up swirl pot and bleed the rad.
Bottom line is that with the plenum and various hoses being the highest points in the system, with the bleed screws and expansion tank well below them, it is damn nearly impossible to expel all the air, and frankly not worth the effort IMHO. If you parked the car sideways on a 60 degree slope it might be possible ...
miniman said:
ATG said:
Once engine is off, then I top up swirl pot and bleed the rad.
Can you elaborate on this please? How exactly do you "bleed the rad"? Sorry for such a dumbass question!
I Used a wood chiesel on it's side. Most chiesels have a square thick shaft . Worked for me as I found that screw drivers dont have square shafts and could easily slip.
I filled mine from the swirl tank with the rad bleed screw out and the expansion cap off, Tighten up and a quick run around the block till warm , let engine cool and refilled from swirl. Then half fill expansion tank. Basically what it says in the handbook.
Trev
I filled mine from the swirl tank with the rad bleed screw out and the expansion cap off, Tighten up and a quick run around the block till warm , let engine cool and refilled from swirl. Then half fill expansion tank. Basically what it says in the handbook.
Trev
The best way I've found to bleed the coolant system is to buy a cheap clear plastic funnel from Halfords, and screw this (push quite hard) into the hole where the brass screw usually sits. Its fairly easy to get this to bite in and form a nice water-tight seal. You should also cut a small amount off the end of the funnel, so that when it is fully screwed in, there is no excess sticking into the tank around which air can collect.
To make this even more effective, I glued a large clear plastic flower pot (with the bottom cut out) into the funnel to increase its capacity to around 4 litres. What you then need to do is fill the system via the funnel (with the expansion tank around 3/4 full), with the heater matrix open, the rad bleed and top blanked off hoses also open. As water starts to come out of the open holes, shut them one by one (rad, then heater hose last). Continue filling until you have a good litre in the funnel above the swirl pot.
Now start the engine (with the funnel left in). Let it warm up and you will see the air bubble up through the funnel bit by bit as the coolant level goes down. Top up as necessary until the engine begins to get warm. Now stop topping up as the expansion of the coolant will cause it to naturally fill right up into the funnel and then flower pot. Rev the engine a bit now and hold the revs up around 4k to push any air out of the system that is still hanging around in any crevices. This will bubble up through the funnel some more and the level will drop.
Now switch the engine off and leave it to cool. The coolant will slowly cool down and the level in the funnel will drop until its pretty much cold. Make sure there is still a small amount of coolant above the level of the swirl pot at all times so no air is drawn back in. When the level settles after you've had a beer or two, unscrew the funnel (a bit will leak out onto the floor so get a rag), and screw the brass cap back in.
If there is any sign of air still in there, shaken free by a few pot holes or spirited driving, the little bit extra in the expansion tank you put in to start will compensate and hopefully level out about 1/2 full where it should be
Really easy to do, and once you've made up your DIY funnel, you can reuse it many times. Works a treat
To make this even more effective, I glued a large clear plastic flower pot (with the bottom cut out) into the funnel to increase its capacity to around 4 litres. What you then need to do is fill the system via the funnel (with the expansion tank around 3/4 full), with the heater matrix open, the rad bleed and top blanked off hoses also open. As water starts to come out of the open holes, shut them one by one (rad, then heater hose last). Continue filling until you have a good litre in the funnel above the swirl pot.
Now start the engine (with the funnel left in). Let it warm up and you will see the air bubble up through the funnel bit by bit as the coolant level goes down. Top up as necessary until the engine begins to get warm. Now stop topping up as the expansion of the coolant will cause it to naturally fill right up into the funnel and then flower pot. Rev the engine a bit now and hold the revs up around 4k to push any air out of the system that is still hanging around in any crevices. This will bubble up through the funnel some more and the level will drop.
Now switch the engine off and leave it to cool. The coolant will slowly cool down and the level in the funnel will drop until its pretty much cold. Make sure there is still a small amount of coolant above the level of the swirl pot at all times so no air is drawn back in. When the level settles after you've had a beer or two, unscrew the funnel (a bit will leak out onto the floor so get a rag), and screw the brass cap back in.
If there is any sign of air still in there, shaken free by a few pot holes or spirited driving, the little bit extra in the expansion tank you put in to start will compensate and hopefully level out about 1/2 full where it should be
Really easy to do, and once you've made up your DIY funnel, you can reuse it many times. Works a treat
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