Cooling issue

Author
Discussion

xover

Original Poster:

340 posts

165 months

Monday 18th September 2017
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Neither of the radiator fans are spinning and the radiator is only half full. I have always had the half full issue even after replacing it, please advise on how I can troubleshoot this.

mfp4073

1,940 posts

173 months

Tuesday 19th September 2017
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Remove the radiator cap, set the heater to it highest temp, then start the engine. Allow the engine to slowly come up to operating temperature. Keep an eye on the coolant level and top it up as required. Replace the radiator cap with a new one and hopefully that will sort the problem out.
If that does not work, I would be looking for a kink in one of the coolant pipes, or maybe a restriction in a pipe somewhere.
The only other thing I can think of is maybe there is a problem with the actual heater valve which is located on the drivers side adjacent to the inner wing. If I any doubt I would also replace that as well.
I believe radiator caps were around £12 and heater valves about £40 ?,
The fact that the radiator fans do not come on could be a faulty relay, a fuse or broken wire, or temp sender.
I would sort out out the coolant level first, you might then find the fans then start to work when system is filled correctly and everything comes up to temperature. Don't forget the fans won't operate unless the engine gets really hot.

I hope that gives you something to work with.

John


Edited by mfp4073 on Tuesday 19th September 08:06

xover

Original Poster:

340 posts

165 months

Tuesday 19th September 2017
quotequote all
Thanks a lot for this.

Should had mentioned that the the engine temp needle hit the top and the alarm started to sound.

I will check all those things you suggested.

monkfish1

10,874 posts

223 months

Tuesday 19th September 2017
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Your radiator cap is defective. Thats why its half full.

The fans could be many (unrelated) reasons.

xover

Original Poster:

340 posts

165 months

Tuesday 19th September 2017
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You replaced this for me in 2014 along with a fan motor. Do they not last long?

mfp4073

1,940 posts

173 months

Tuesday 19th September 2017
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xover said:
You replaced this for me in 2014 along with a fan motor. Do they not last long?
I would expect a radiator cap to last more than three years, but I guess in reality they can go at anytime.

John

xover

Original Poster:

340 posts

165 months

Tuesday 19th September 2017
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It's not going to hurt to try

xover

Original Poster:

340 posts

165 months

Tuesday 19th September 2017
quotequote all
mfp4073 said:
Remove the radiator cap, set the heater to it highest temp, then start the engine. Allow the engine to slowly come up to operating temperature. Keep an eye on the coolant level and top it up as required. Replace the radiator cap with a new one and hopefully that will sort the problem out.
If that does not work, I would be looking for a kink in one of the coolant pipes, or maybe a restriction in a pipe somewhere.
The only other thing I can think of is maybe there is a problem with the actual heater valve which is located on the drivers side adjacent to the inner wing. If I any doubt I would also replace that as well.
I believe radiator caps were around £12 and heater valves about £40 ?,
The fact that the radiator fans do not come on could be a faulty relay, a fuse or broken wire, or temp sender.
I would sort out out the coolant level first, you might then find the fans then start to work when system is filled correctly and everything comes up to temperature. Don't forget the fans won't operate unless the engine gets really hot.

I hope that gives you something to work with.

John


Edited by mfp4073 on Tuesday 19th September 08:06
Do I fill it to the top once it's heated up to temperature at idle and then put the lid on and see if it leaks to test the cap?

mfp4073

1,940 posts

173 months

Tuesday 19th September 2017
quotequote all
xover said:
Do I fill it to the top once it's heated up to temperature at idle and then put the lid on and see if it leaks to test the cap?
I usually fill up the radiator when the engine is cold. Fire up the engine and as the thermostat opens the water level will drop as the coolant circulates around the engine block and through the heater matrix. Make sure the heater is on hot. I then just add coolant as necessary until the level is full again.
After say 10mins or so, give the engine a few gentle Revs, you should feel some heat from the heater by this time. Re check the level in the radiator, the water will be getting hot so watch out!
Put the radiator cap back on, and let the engine continue to tick over and check for leaks.....everywhere.
If all is well take the car out for a gentle drive and leave the heater on. If you hear any water bubbling in the system you will have an air lock, but it should self bleed.
When you get back home let the engine cool right down, then check the level again.
Hopefully job done!

John

monkfish1

10,874 posts

223 months

Tuesday 19th September 2017
quotequote all
xover said:
You replaced this for me in 2014 along with a fan motor. Do they not last long?
They are truly rubbish. Sold heaps of them over the years.

Either you have a leak or the cap is defective.

xover

Original Poster:

340 posts

165 months

Wednesday 20th September 2017
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It looks like the coolant is leaking out of the plastic shaft on the left side when facing the car. There is a pool on the floor when I checked my car this morning after doing the testing yesterday. The levels had stayed ok, but when I checked it this morning it was right down again.

The fans are actually working, as you said it has to be really hot before they come on, so that isn't so bad.

I actually found that when I heated it up the level went up opposed to down. Is that correct?

Edited by xover on Wednesday 20th September 11:39

mfp4073

1,940 posts

173 months

Wednesday 20th September 2017
quotequote all
xover said:
It looks like the coolant is leaking out of the plastic shaft om the left side somewhere as there is a pool on the floor when i checked my car this morning and the fluid has gone down again, but its a slow leak I think.

The fans are actually working, as you said it has to be really hot before they come on.

I actually found that when I heated it up the level went up opposed to down. Is that correct?
The level will more than likely go up and down as the engine heats up. This will just be the air locks working their way through the system. I usually squeeze the coolant pipes by hand to get the air out a bit quicker, the rad cap should be off and the engine running in order to do this. Make sure that you don't catch your hands or clothing on anything hot or moving, it never ends well!
I'm not sure where you mean by a leaking plastic pipe, but a coolant leak will leave a trace of crystals as it dries out, you might then be able to trace the leak.

John


xover

Original Poster:

340 posts

165 months

Wednesday 20th September 2017
quotequote all
So when the engine is cold should it be filled to the top because I found that when I heated it up the fluid started rising to the top so I just put the cap on.

mfp4073

1,940 posts

173 months

Wednesday 20th September 2017
quotequote all
xover said:
So when the engine is cold should it be filled to the top because I found that when I heated it up the fluid started rising to the top so I just put the cap on.
Yes, that is the way I do it. Don't forget to squeeze the two large radiator pipes, top and bottom. Once the air is out you can top it up again. Sadly it is a messy job!
When you think it's full put the rad cap on.
Don't forget with the rad cap on the system will pressurise as it heats up, so if you remove the cap you will spray boiling hot coolant everywhere.
You're best bet is once you have fixed the leak, and topped up the rad, put the cap on and let the engine heat up to running temp, then let it cool down and top up as required.
Keep checking the level when cold over a couple of days.

John

THUNDER STORM

1,251 posts

168 months

Wednesday 20th September 2017
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From what you say you may need a new radiator. Go for the all Aluminium one, dont go for OE it will be trouble again with the plastic ends on the radiator. See also Epic coolant leak September 18 on this forum

Adebyebye

Edited by THUNDER STORM on Wednesday 20th September 19:44

xover

Original Poster:

340 posts

165 months

Thursday 21st September 2017
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I replaced the radiator 15k ago and the cap a second tine, pressure tested the radiator today, seems ok, the mechanic thinks it's leaking through the head gasket. Anyone had this issue before ?

Edited by xover on Thursday 21st September 14:22


Edited by xover on Thursday 21st September 14:32

mfp4073

1,940 posts

173 months

Thursday 21st September 2017
quotequote all
xover said:
Pressure tested it, seems ok, the mechanic recons it's leaking into the head gasket. Anyone had this issue before ?
Blimey...things are going from bad to worse.
If the head gasket has failed you might get a misfire or hesitation under load. You may also find that you have a mixing of oil and coolant. Look out for oily sludge in the coolant and maybe a mayonnaise type of sludge mixed with the engine oil, and found on the inside of the oil filler cap. Don't confuse the Mayo effect with short stop start journeys which is caused by the engine not getting hot enough to burn off the condensation inside the engine.
TBH, I could be wrong, but a failed head gasket must be a rare thing on these engines. Then again it would depend on how you use the car. If your car is supercharged then a failed gasket would be understandable.

John

xover

Original Poster:

340 posts

165 months

Thursday 21st September 2017
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It sits around in the car park. I've done 25k in 7 years. Occasional weekly short trip and then 200mile round trips a few times per year. It's NA except for the air filter and full exhaust. No cam or FI.

Mechanic was saying that it is burning oil as there's black sludge in the exhaust, is that a correct analysis? I do notice grey smoke under heavy acceleration, can't tell if its blue or white though, more white grey than blue grey I would say.

Edited by xover on Thursday 21st September 16:13


Edited by xover on Thursday 21st September 16:14

mfp4073

1,940 posts

173 months

Thursday 21st September 2017
quotequote all
xover said:
It sits around in the car park. I've done 25k in 7 years. Occasional weekly short trip and then 200mile round trips a few times per year. It's NA except for the air filter and full exhaust. No cam or FI.

Mechanic was saying that it is burning oil as there's black sludge in the exhaust, is that a correct analysis? I do notice grey smoke under heavy acceleration, can't tell if its blue or white though, more white grey than blue grey I would say.

Edited by xover on Thursday 21st September 16:13


Edited by xover on Thursday 21st September 16:14
My Monaro has 64,000 miles on it and it has few mods. I bought it 10 yrs ago and I have never had to top up the oil between services. It has never blown any blue or grey smoke out of the exhaust either.
If you have any smoke coming from the exhaust I believe that should direct you to the problem.
I'm no mechanic but blue smoke would indicate oil, as well as an oily smell, and white smoke would indicate water vapour, that might indicate your head gasket problem.
If you do not have to keep topping up your engine oil regularly, we can forget worn valve guides/ seals and the like.
You will have to find out which cylinder bank is a likely suspect so you can remove the correct cylinder head to confirm a defective gasket.
I seem to recall years ago that you might be able to confirm a blown cylinder head gasket by analysing the coolant for blow by gases?
You could always remove both cylinder heads and get them ported and polished while your at it!!!
This job is not easy is it?

John

fred bloggs

1,300 posts

199 months

Thursday 28th September 2017
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How long have you been running around with the radiator half full ?