Coolant leak, full resevoir gone in 24 hours, should I replace water pump?

[Eskiio]

Hi All,

First post

I've picked up my 05 KJ Limited in September last year. It was at 124k, 1 owner, full service history. There aren't many of these in the road in Australia anymore, I've seen 3 in the last year. Been stoked with it!

There were a few items on the checklist to get it rock solid to become a daily driver.

The last outstanding repair was a very minor coolant leak, which my Jeep mechanic said it was from the the timing cover.

The bandaid fix was to top up the resevoir every 2-3 weeks.
Across 4500km and 6 months I only used 2.5L of coolant in top ups.

In recent days my KJ is losing a full reservoir of coolant/water per 20 minute drive (only used water in last few days to help diagnose).

Doesn't seem like a hose, thinking its the water pump or gasket/weep hole (see photos)

Side notes:

• Water pump was previously replaced at 94,000 km in Sept 2020.
• Green coolant was used in previous ownership

Can anyone confirm that water pump replacement should do the trick or had a similar type of leak?

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

Other than oil changes, I'm a total rookie. I watched as recommended in other threads:

xc_hide_links_from_guests_guests_error_hide_media

Would this be a task to avoid as a newbie or worth giving a shot to repair with a replacement pump?

I have recently moved and its now a 120km drive to my Jeep mechanic. Would the KJ survive a 120km drive to the mechanic (with some pitstops to top off coolant along the way of course) or not worth the risk?

Thanks!

 

[KJowner]

Coolant colour doesn't mean much, different manufacturers use different colours.
I'd fix that leak before driving too much, if you run out of coolant you will warp the heads and the repair bill will be eye watering...
I'd imagine it is easily DIYable, assuming you have tools, I'm a mechanic with a machine shop so I tend to look at everything as DIY! I can't offer much specific advice on the V6 as I've never worked on one, mine are CRDs but I'm sure some of the American guys will be online later and able to give you more advice.
Your engine should be using HOAT coolant not Glycol or OAT based. Can take a bit of finding because it's a US spec. However JCB also recommend it for there engines so it is available globally.
If your engine has had some other chemical mix coolant then it will require a full flush before refilling as the different types don't mix well!

 

[Eskiio]

Coolant colour doesn't mean much, different manufacturers use different colours.
Your engine should be using HOAT coolant not Glycol or OAT based. Can take a bit of finding because it's a US spec

I've been using Si-OAT

Looking at the service history they mention "green coolant" so I wondered if they were using IAT, considering the water pump was repalced only 4 years ago, so thought it was mentioning, but other than the cometic colour, I'm unsure on the spec

Considering I haven't been using HOAT, I myself may be the one causing damage to the cooling system

 

[KJowner]

I've just watched the video you attached, it looks like a nice easy job compared to the diesel!
If you do it just make sure all the seal faces are nice and clean so you don't get any leaks from the gasket.

 

[KJowner]

Maybe, the coolant chemistry is usually selected to match the different metals used.

 

[Eskiio]

Thanks for taking the time to watch the vid! It was a gold nugget when doing some research via the forum

If I end up going the DIY path, I’ll make sure the sealing surface is properly cleaned / prepped... thanks!

I came across some suggestions about replacing the tension belt if replacing the water pump. Should I consider this too?

Though still a little unsure if it is the timing cover as originally suspected (not the pump.. or both), now the main hesitation on doing things myself

 

[KJowner]

I doubt it's the timing cover, they don't normally have anything to do with coolant (I'm not familiar with the engine so general comment! ) It's possible that a leak higher up is running down and looks like it's leaking from there.
It's worth assessing the condition of the drive belt and all the pulleys while you're doing the job, a snapped belt or failed bearing in a pulley will cause a boil up so check everything. If the belt is old just replace it anyway, they are cheap.

 

[CheddarGau]

If the leak is pretty bad fill with water, run it and then let it sit once on the warm side. If it's a bad leak you will see the water dripping our pouring out from whatever is leaking. With the engine off and the level high enough it won't be whipped around by the belt and pulleys. Let us know what you find. Water pump bolts to timing cover. If timing cover were the one leaking there would be a good chance the coolant would enter the crank case into the oil. No always, but I would check the exterior coolant related items first. Water pump, thermostat housing, etc.