[geeyoutoo]

Can you top up coolant to correct levels (including the header tank and surge tank) and drive it until it reaches jormal op temp, then pull over and turn engine off, raise bonnet and stand beside the lower tank with the yellow cap and listen for gurgling, if you hear that the head needs to come off, head gasket most likely and possible cracked head, but head cracks don't normally extend to water galleries.
Could also be a blocked core, that crap in the pic is astounding.

 

[geeyoutoo]

You can buy gasket material in various types in sheets from Repco that work well in this type of setting, you can make your own gasket easily enough, use a high quality gasket 'goo' sparingly.
I have several sheets of various types just in case, used them successfully on quite a few occasions.

 

[geeyoutoo]

Just a update, dropped all fluids and flushed the cooling system. Haven't taken it for a drive yet but have sat here for about 5 mins with the warm up switch (I think that's what it is?) on and nothing over half.
Also smoke has now cleared. Mechanic watched the video and deemed that to be over fueling.
Going to get the fan belt changed again thiugh. It needed to be sprayed with belt conditioner again to stop the ticking. The belt is only 18mnrhs old and maybe 10k km


Edit: took her for a drive made it about 5 mins a d over heated. Guessing it has to be a water pump.

Belt spray should never be used on the serpentine belt unless in emergency, once used change belt ASAP. We have heard of length issues with non genuine belts, the dimension tolerance is quite tight. It maybe a good practise to check out the belt tensioner while your at it, bushes can wear causing a change in belt tension.

 

[geeyoutoo]

Can anyone confirm if this is normal.
I did just flush and drop the water so could it possibly be air?
26 January 2023


Still trying to troubleshoot sorry guys.
I had the coolant tank to full. But weirdest side effect has just popped up.
Running it with the the heating switch on and temp was normal turned it off to check for bubbling like @geeyoutoo reccomended and no bubbling.(edit: after the below issues the coolant rank was bubbling and the overflow was pressurised)
Started it back up and ran it at about 3k noticed the temp drop dramatically and the heater is no longer pumping hot air.
The temp gauge was moving with the revs but has since normalised.

Air needs to be evacuated from the system when refilling, air pockets always exist and must be removed. In my build thread I detailed a method of bleeding using a cut down soft drink bottle with a hole drilled in the cap pushed into the radiator filling neck, this allows you to fill the radiator above the top plastic tank level, as level drops you add more coolant, leaving the engine on fast idle makes it easier to monitor once thermo opens.

 

[geeyoutoo]

Tha ks for your time. I just keep going back to worst case scenario.
I'm starting to lean towards a dodgy thermostat or water pump. The stopping of the heater blowing hot air is confusing me.

Sounds like an air pocket.

 

[geeyoutoo]

I would do that again but make sure the 'funnel' is sealed around the base some of those bubbles could possibly be entering from there. You need to run engine to normal operating temp to ensure thermo has opened (but it could be clogged). There is a coolant line that runs from the bottom of the top tank over to the block, I would be checking that is flowing freely. If coolant is flowing through the heater, the hoses at the firewall should be hot.

 

[geeyoutoo]

@geeyoutoo managed to seal it up and managed to get some hot air out of heater.

Line from top tank to block is flowing. Water is still bubbling.
What I have noticed though is if I fill the top tank it sucks it straight into the rad and overflows my funnel.

If it's not a head/headgasket I'm really starting to lean towards a stuck thermostat.

Checking thermostat is a lot easier, so I would start there but sadly I'm not sure that is the issue.

 

[geeyoutoo]

also put a vice grip near cap overflow on small hose from top tank to coolant resy

Why! I've never needed to do that, and I've done it many times in the 23 years of owning my Patrol, to complete circulation the flow out from under the top tank is required.

 

[geeyoutoo]

I closed the main tank and filled from the top tank with a sealed funnel.
I am still getting severe bubbling so sadly think I have a headgasket issue.
@geeyoutoo is it possible for this to happen and not have white smoke out the exhaust?

Yes it is, I had no white smoke when my gasket failed to the small water gallery between cylinder 3 and 4. I had done pressure tests, I had done the sniff test and all passed (we do know the sniff test on diesels is not always effective), but I still had bubbling in the lower tank so time to remove head and look.

 

[geeyoutoo]

Yeah I'm pretty certain it's a small leak in the gasket. If it was a piston I'm sure I would have loss of power.

Absobloodylutely!

 

[geeyoutoo]

if u are in perth wa i have a test kit u could use to check exhaust leak.. i picked it up just before christmas to check mine.

Check my post #27, sniff testing a diesel cooling system is not reliable, I knew it already but had a local guy do it anyway, it passed and I still had bubbling.

 

[geeyoutoo]

Just to add my experience to this. I found it difficult to remove air lock without pressuring the system.

The funnel/ plastic bottle method should work with heater on but I found it didn’t seem to fully circulate without the cap on the header tank.

Interesting, not my experience after many coolant changes. Just to clarify, I also have the pressure cap off the upper tank.

 

[geeyoutoo]

Cheers guys
It is now bubbling the coolant res instantly so definitely a head gasket.
Just really hoping that's all's it is

Keep us informed mate.

 

[geeyoutoo]

Just go’s to show every car a little different. I have had mine for 13 yrs and done about 8 flushes over that time use to fill from radiator then about 8 yrs ago started filling from top tank and seemed to work better so just kept doing it. With mine i need to rev a bit for it to heat up enough for thermostat to open and normally go for a quick drive afterwards then check coolant once back and cooled down a bit. So far this works for me.
best of luck with the head gasket flow.

I put mine on fast heat up idle, 1200rpm.

I've had mine 22/23 years and 425,000k, lost count of the coolant changes, did about 4 in a row while seeking answers to my small coolant loss but no overheating whatsoever, weep in head gasket.

 

[geeyoutoo]

This is kinda related- Just about to put a MLS Head gasket in our ZD30 and noticed some gasket sealant on the old gasket.

I said to myself ”that probably why the gasket was blowing” but now after cleaning the head I see signs of No4 overheating and the head corroding.

I am wondering if the reason for the sealant was to combat the corroding head?

any thoughts- should I add a bit of RTV?

View attachment 549600

Whoa, what coolant was used? Battery acid????
But anyway now it is clean, No, no, no, no, do not use rtv, heads do not corrode if good suitable coolant is used.
I have built hundreds of engines over my time, many with alloy heads, the only stuff I have ever used successfully was copper coat spray, but very sparingly, I used nothing when I changed the headgasket on my DI, only followed the fitting instructions to the letter and did the final tighten stages to the max settings.

 

[geeyoutoo]

So you think the MLS gasket should seal ok given the state of the head?

the only time I’ve seen one like this was a motorcycle that had an over heating issue and I think the aluminium had denatured a bit

Have you run a straight edge over the head to see if it is badly warped? But having said that I have raced cars with aluminium heads and yes some have warped, we never machined the warp out, the main reason was combustion chamber size, if you machine the head flat you alter the comb chamber size when originally you have gone to a lot of trouble to make them all 'exactly' the same. We would pull the head down on a mill table and lightly machine out small defects, then release the head and any original warping would return, no problem because like the mill table you pull the warp out, never had an issue. If you are concerned then a light spray of copper coat would not go astray.
Here is one I found in google.
My 2 cents worth from a lot of experience.

VHT Copper Gasket Cement 11 oz. - SP21 | Adhesives | Chemicals, Cleaners & Adhesives | Paint & Panel | Autobarn Category | Autobarn

SP21 COPPERCOAT GASKET CEMENT VHT VHT Copper Gasket Cement has been formulated with the same ingredients as our world-renowned high temperature coatings. VHT Copper Gasket Cement maintains excellent adhesion under severe pressure and heat fluctuations. This high-metallic formula assures tight...

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