Coolant level

Coolant level

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Discussion

Peter-j8c3u

Original Poster:

110 posts

44 months

Wednesday 15th December 2021
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My coolant level seems to be very low all the time,as in I can’t see it in the expansion tank!!
I’ve been told they all do it and I’ve not topped it up but it’s playing on my mind. It doesn’t overheat and the temp gauge only rises a little in slow traffic.
Is it a Cerbera thing?
Could it be airlocked, what’s the correct bleed procedure?
How can I confirm if the head gasket has gone?
Thanks

pmessling

2,308 posts

217 months

Wednesday 15th December 2021
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Fill it to the middle line (seam) all cerbs seem to have a differing level that suits the car, however it could have a leak. Check all your pipes and jubilee clips. Bleeding is nose slightly raised. Rad then rails.

I use a pressure tester to bleed mine can be done cold and test for leaks.

Then a final bleed when the engines up to temp.

Peter-j8c3u

Original Poster:

110 posts

44 months

Wednesday 15th December 2021
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Well I’ve just bled it. Topped up the tank,bled the rad and the pipes,checked tank was at the halfway (join) mark. It ran fine on the driveway, up to 95/fan came on/dropped down to 90. I loosened the rad bleed a little,as you would a home rad to check for air and it was fine,a slight trickle of coolant. With no leaks anywhere, took for a spin in rush hour traffic, 85 moving,cycling between 90 & 95 in queues. I was out for 40 mins,I was in mostly slow traffic,2 queues for 5 mins and another for at least 10 mins,lots of drivers in front of me were turning round but I stuck it out until I crawled up to a junction I could turn in. Got home and waited 1/2 hr to cool down before taking the ex tank cap off and the level was just above the bottom of the little window, so just a tad lower and all seems well...phew!!
I must add that the rad bleed screw had a damaged red fibre washer on it which I replaced with an o ring. That must’ve made the difference, I didn’t see much air come out when I initially bled it but it’s tricky to see when you’re at the ex tank. I had left the cap on when I removed the rad bleed screw and simply tightened the cap up when coolant came out the rad. I will check all the hose clips tomorrow as it’s dark now.
What initially concerned me was after I first bought the car I was out for a blast on one of my favourite routes, it was a scorcher of a day and I came across some roadworks that had 4 way traffic lights, the temp went up to 105 and I ended up having to shut it off when I saw steam coming from the ex tank area of the bonnet. The fan had kicked in but couldn’t keep the temp down.
So it must’ve either been the bad fibre washer and/or air in the rad. It may not be scorching weather but rush hour traffic and queuing would surely have shown a problem.

pmessling

2,308 posts

217 months

Wednesday 15th December 2021
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You can contact joolz of kits and classics for a modded cooling chip to bring the fans on earlier.

MoonMonkey

119 posts

141 months

Wednesday 15th December 2021
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If the head gasket has gone you can usually see white smoke coming out of the exhaust on that bank.

Head gaskets can fail prematurely on little used cars as the block is wet lined leaving the gasket sat in a pool of coolant. The fibre material then falls apart over time and leaves the fire ring un supported, allowing it to blow.

TBH it doesn’t sound like yours has a head gasket failure. I’d also look at replacing the cap on the expansion tank, as they can leak under pressure when old. It’s a VAG part

Edit I’m assuming you have a V8

Edited by MoonMonkey on Wednesday 15th December 21:02

Peter-j8c3u

Original Poster:

110 posts

44 months

Wednesday 15th December 2021
quotequote all
MoonMonkey said:
If the head gasket has gone you can usually see white smoke coming out of the exhaust on that bank.

Head gaskets can fail prematurely on little used cars as the block is wet lined leaving the gasket sat in a pool of coolant. The fibre material then falls apart over time and leaves the fire ring un supported, allowing it to blow.

TBH it doesn’t sound like yours has a head gasket failure. I’d also look at replacing the cap on the expansion tank, as they can leak under pressure when old. It’s a VAG part

I’m going to replace the tank too when I do some other jobs.

Edit I’m assuming you have a V8

Yes,4.5

Edited by MoonMonkey on Wednesday 15th December 21:02

Peter-j8c3u

Original Poster:

110 posts

44 months

Wednesday 15th December 2021
quotequote all
pmessling said:
You can contact joolz of kits and classics for a modded cooling chip to bring the fans on earlier.
Oh,can’t just change a temp sender then rolleyes

Byker28i

74,527 posts

231 months

Thursday 16th December 2021
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No the fans are driven from a command from the engine ecu set at certain temps. Joolz brings them in 5 degrees C earlier which helps stop the car getting too hot before the fans kick in.
Top temp of 95 is ok, but it is cool out at the moment. Mine runs around 85 currently when moving, in France at 40C it got just over 100 on the guage, but its best to compare the gauge reading with the value recorded in the ECu using one of the diagnostics because the gauge can read high as the capilary runs through the engine bay.

Not a problem, but it's just good you know the difference

Edited by Byker28i on Thursday 16th December 09:23

Peter-j8c3u

Original Poster:

110 posts

44 months

Sunday 19th December 2021
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Interesting, I’ll add it to my list of things to do as I’m sure it’s a different story in the summer.
I was out yesterday for about 4 hours and it was absolutely fine. Sat consistently at 80 degrees and only went up in slow traffic so I’m not going to worry anymore.

DuncanM

6,876 posts

293 months

Monday 20th December 2021
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Peter-j8c3u said:
Interesting, I’ll add it to my list of things to do as I’m sure it’s a different story in the summer.
I was out yesterday for about 4 hours and it was absolutely fine. Sat consistently at 80 degrees and only went up in slow traffic so I’m not going to worry anymore.
Good news regarding the coolant/temp since you've bled the system.

Have you sorted out the oil pressure issue you were having?

Peter-j8c3u

Original Poster:

110 posts

44 months

Monday 20th December 2021
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DuncanM said:
Good news regarding the coolant/temp since you've bled the system.

Have you sorted out the oil pressure issue you were having?
I’m wondering if there would be a difference in coolant level if there was more orange coolant than de-ionised water but yeah happy.

I topped the oil up and I’ve noticed that it sits at 45 on tickover,50-55 normal driving and 60 spirited driving although I’m only having the odd glance then!!
If you remember I initially reported the gauge acting kind of stiffly. It still is but I think it’s loosened up very slightly, it could be that I’m going on longer drives and hot cycles are doing something,it wasn’t used very regularly before I had it.
I’m trying to find the pipe/line that goes to the gauge to see if it’s got a kink in it or something daft. I assume a copper line comes off the engine somewhere and goes to the gauge right?
Spring seems fine but I’m going to order a new one anyway along with a couple of other bits and bobs.

DuncanM

6,876 posts

293 months

Monday 20th December 2021
quotequote all
Peter-j8c3u said:
I’m wondering if there would be a difference in coolant level if there was more orange coolant than de-ionised water but yeah happy.

I topped the oil up and I’ve noticed that it sits at 45 on tickover,50-55 normal driving and 60 spirited driving although I’m only having the odd glance then!!
If you remember I initially reported the gauge acting kind of stiffly. It still is but I think it’s loosened up very slightly, it could be that I’m going on longer drives and hot cycles are doing something,it wasn’t used very regularly before I had it.
I’m trying to find the pipe/line that goes to the gauge to see if it’s got a kink in it or something daft. I assume a copper line comes off the engine somewhere and goes to the gauge right?
Spring seems fine but I’m going to order a new one anyway along with a couple of other bits and bobs.
Oh that sounds good news on both oil and coolant smile - fwiw, I don't think it's good to have too much coolant in the expansion tank, the engine self bleeds and will push coolant out if overfilled, scarying you into thinking all sorts of awful things.

The behaviour of your temp gauge and oil pressure, both sound good to me thumbup

Mr Cerbera

5,126 posts

244 months

Wednesday 29th December 2021
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Peter-j8c3u said:
My coolant level seems to be very low all the time,as in I can’t see it in the expansion tank!!
I’ve been told they all do it and I’ve not topped it up but it’s playing on my mind. It doesn’t overheat and the temp gauge only rises a little in slow traffic.
Is it a Cerbera thing?
Could it be airlocked, what’s the correct bleed procedure?
How can I confirm if the head gasket has gone?
Thanks
Hi Peter wavey

Although Cerbs may feel that they can defy the Laws of Physics, Cap'n, they can't.

A fully secured Cerb should notrun at a low water level.

This is the Header Tank's Level Marker ....


I had a problem similar to the one you describe.

There is a Junction at the back of the odd-numbered Cylinder Head, where the Flexible Header Pipes and the Header Tank Pipe meet....



The piece which links the three pipes is a cheap piece of plastic which can crack at he blink of an eye....



I changed mine for a Brass one (from a Garden Centre) and have never had the problem again.

HTH
thumbup

LucyP

1,773 posts

73 months

Wednesday 29th December 2021
quotequote all
Mr Cerbera said:
This is the Header Tank's Level Marker ....
But it's the marker for the VW/Audi engine that it was designed to be used with. Not the TVR one, so it isn't necessarily the right level for a TVR, just because it is for a VW. That's the problem.

Byker28i

74,527 posts

231 months

Wednesday 29th December 2021
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I swapped out my Y piece as well, probably more expensive getting the racing green one
https://partsfortvrs.com/tvr-parts/part-details/tv...

Peter-j8c3u

Original Poster:

110 posts

44 months

Wednesday 29th December 2021
quotequote all
Mr Cerbera said:
Hi Peter wavey

I changed mine for a Brass one (from a Garden Centre) and have never had the problem again.

HTH
thumbup
Hi,
It’s on my shopping list. I’m going to have the windscreen out,I’ve also got to remove the header tank,which I’ll replace with a new one, so I can change my wiper motor as it seems too tall, which needed its park switch changing anyway thumbup

Mr Cerbera

5,126 posts

244 months

Thursday 30th December 2021
quotequote all
Peter-j8c3u said:
Hi,
It’s on my shopping list. I’m going to have the windscreen out,I’ve also got to remove the header tank,which I’ll replace with a new one, so I can change my wiper motor as it seems too tall, which needed its park switch changing anyway thumbup
Wow ! It'll be interesting to know what motor you choose as I'm very interested in changing my old clunker thumbup

LucyP said:
Mr Cerbera said:
This is the Header Tank's Level Marker ....
But it's the marker for the VW/Audi engine that it was designed to be used with. Not the TVR one, so it isn't necessarily the right level for a TVR, just because it is for a VW. That's the problem.
Good thinking Luce, I never thought of that thumbup
However, since finding that mark, wit a torch, I haven't had a problem thumbup
(What have I said yikes )


Edited by Mr Cerbera on Thursday 30th December 21:27

MattPlaneCrank

107 posts

52 months

Friday 31st December 2021
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A previous owner had cut the hoses off and scored the Y-piece. One of those cuts went right through causing a leak. I changed it for the Racing Green part. Particularly annoying small leak that dripped into the soundproofing and then re-appeared on the garage floor in a different location at a later date! grumpy

TwinKam

3,321 posts

109 months

Friday 31st December 2021
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Plenty of choice on the 'bay' at <£5 incl delivery... I opted for this shape that installs neater due to its asymmetric legs.

MattPlaneCrank

107 posts

52 months

Friday 31st December 2021
quotequote all
TwinKam said:
Plenty of choice on the 'bay' at <£5 incl delivery... I opted for this shape that installs neater due to its asymmetric legs.
One wonders in which country that was manufactured? confused