Cooling system problems..

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Saffles
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Lid geworden op: 10 dec 2009, 13:08

Cooling system problems..

Bericht door Saffles »

Hi Guys!

Yes, i still have my safrane!

I found that the head gasket had gone bad. I have two guesses why... the automatic gearbox puts too much weight on the head bolts when lifting the engine on a crane and / or the cooling system which stopped working.

Anyway, i've got the head gasket done.

Now i've trying to refill it with coolant. I can only get it to take about 4.5L of coolant. When i start it, the temperature goes up, i turn it off. I turn the ignition back on and the needle drops to a much lower temperature.

I have tried bleeding it but still cannot get any air out of it. Also my bleed screws keep leaking...

Help!
www.safrane.info

Email: Saffles@

2.5 20V Ph2
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AS1 (Anne)
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Lid geworden op: 24 mar 2007, 12:25
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Re: Cooling system problems..

Bericht door AS1 (Anne) »

Welcome back!

You will be amazed at how much just one head bolt can take and you have 10 of them.
How did you determine that the head gasket is bad?

You should see some coolant flowing back to the expansion tank with the engine running. This tells you the water pump is working.

Make sure you have opened all bleed screws and close them when no longer any air comes out. Don't open them with the engine running!

Then let it run at fast idle (1500 rpm) for 4 minutes with the the expansion tank cap off.
Let it cool off. You should see a drop in coolant level. Then repeat this procedure.

It can be a pain to get all the air out. It took me 4 tries recently on my R25 V6. Even after a long drive I had to add half a litre.
R25 V6 Injection aut. LPG 1989 met ac, cc, leer
Clio 1.4 16V privilege aut. 2002
Clio 1.4 RN 1993
Saffles
Berichten: 128
Lid geworden op: 10 dec 2009, 13:08

Re: Cooling system problems..

Bericht door Saffles »

AS1 (Anne) schreef: 04 jul 2022, 21:50 Welcome back!
Thanks! It's been a few years! I became a dad in 2015 and since then the safrane has been pretty neglected. It's just sat outside for 6 years with very little done to it.
AS1 (Anne) schreef: 04 jul 2022, 21:50 You will be amazed at how much just one head bolt can take and you have 10 of them.
The problem is that on the timing belt side of the 2.5, the lifting loop is part of the bracket for the alternator etc which is bolted to the bottom of the engine. On the other side, the lifting loop is bolted to the engine head - which then has to support the bottom of the engine AND the automatic gearbox when you lift it. I don't think those bolts are designed for that. When i removed the head, cylinders 3,4 & 5 had white mayo round them on the head gasket. Cylinders 1 & 2 were fine however the gasket was clearly badly rusted and crumbling.

Afbeelding

Afbeelding

Afbeelding

Afbeelding

Afbeelding
AS1 (Anne) schreef: 04 jul 2022, 21:50 How did you determine that the head gasket is bad?
I was seeing white mayo under the oil filler cap.
AS1 (Anne) schreef: 04 jul 2022, 21:50 You should see some coolant flowing back to the expansion tank with the engine running. This tells you the water pump is working.
Ok, thanks
AS1 (Anne) schreef: 04 jul 2022, 21:50 Make sure you have opened all bleed screws and close them when no longer any air comes out. Don't open them with the engine running!
I've done that but despite filling up via the radiators top hose (and watching coolant flow up into the coolant bottle / tank) i could still only get about 4.5L into it. Coolant also started to run out of the thermostat housing too so it's gone into the engine and come to the top!! The radiator seems ok - I blasted it with the garden hose and water came back out at the bottom very fast.
AS1 (Anne) schreef: 04 jul 2022, 21:50 Then let it run at fast idle (1500 rpm) for 4 minutes with the the expansion tank cap off.
Let it cool off. You should see a drop in coolant level. Then repeat this procedure.
Ok, i'll try that.
AS1 (Anne) schreef: 04 jul 2022, 21:50 It can be a pain to get all the air out. It took me 4 tries recently on my R25 V6. Even after a long drive I had to add half a litre.
I've been a bit scared of running it up like that with no guarantee of cooling fans working in case it blows the head gasket again but i'll give it a go.

I had to buy a new head gasket from Volvo dealers for this engine. That was tricky as they had no idea which one to order and they're all different even though there are many engines using the same basic engine block / cylinders. Eventually we narrowed it down to two - the B5254S or the B5254FS. He ordered in both for me so we could compare them. Can you spot the difference?!!

Afbeelding

The one at the top is for the B5254S.
The middle one is for the B5254FS.
The bottom one is the one i removed from the engine.

On the left side of the one at the top, there is two holes missing - look at the one below and you will see there is an extra hole like the original at the bottom!!
www.safrane.info

Email: Saffles@

2.5 20V Ph2
Saffles
Berichten: 128
Lid geworden op: 10 dec 2009, 13:08

Re: Cooling system problems..

Bericht door Saffles »

Saffles schreef: 04 jul 2022, 20:39 Now i've trying to refill it with coolant. I can only get it to take about 4.5L of coolant. When i start it, the temperature goes up, i turn it off. I turn the ignition back on and the needle drops to a much lower temperature.
Finally... after 12 long years i got to the bottom of this today. :D :D :D

Every time i had the engine running, the temperature needle on the dashboard would go up quicker than it used to. Switch off the engine and then turn the key to the "on" position and the needle would not go back up as high. This bugged me for many years but i never understood why or what was causing it.

One thing i did notice was that the engine block always had 1.2V on it. It's a replacement engine with a different wiring loom (the original engine, autobox and wiring loom are in storage). A couple of days ago i measured the current from the engine block to the battery - 140mA. The earth / group strap at the back of the engine was fine yet the engine was 1.2V and the chassis was 0V.

Eventually i realised that the earth strap is ok but the connection from it to the chassis was not! Today i took the strap out, cleaned it up and then cleaned up the contact on the chassis that it attaches to. Sure enough, 0V on the engine.

Started it up, still 0V. 0V on AC too so no alternator fault. Then i watched the temperature needle - it went up a lot slower than normal - it didn't want to go past 1/3 but before i cleaned the earth connection, it would go almost to the top of the gauge - in less than 2 minutes (and then i'd turn it off - probably why the fans never worked).

So now that the temperature gauge is working properly i was able to do what the service manual says - run it at 2500rpm until the fans activated.. and sure enough... THEY DID!!!
www.safrane.info

Email: Saffles@

2.5 20V Ph2
Gebruikersavatar
AS1 (Anne)
Administrator
Berichten: 3786
Lid geworden op: 24 mar 2007, 12:25
Locatie: België

Re: Cooling system problems..

Bericht door AS1 (Anne) »

That's great news :D !

I've had similar issues on my R25 and solved it by adding another earth from the battery directly to the engine. This can fix all kinds of weird electrical issues.
My gearbox to chassis connection looked ok but maybe it wasn't...
R25 V6 Injection aut. LPG 1989 met ac, cc, leer
Clio 1.4 16V privilege aut. 2002
Clio 1.4 RN 1993
Saffles
Berichten: 128
Lid geworden op: 10 dec 2009, 13:08

Re: Cooling system problems..

Bericht door Saffles »

I did think about using a jump lead to the engine and battery but was a bit scared that i'd damage the ECU..

Anyway i had it running again yesterday, fans still working.. i think this issue is finally resolved! Now i just need to get it through an MOT (safety test)..
www.safrane.info

Email: Saffles@

2.5 20V Ph2
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