JD 6620 coolant leak

[Flat 10]

Going to pull it apart to look closely tomorrow as not at all obvious where its coming from. Initially thought it was from the O ring between header tank and rad but doesn't appear to be.
Rad Core and inside of fan seem dry. Outside of fan very wet and thrown all up over header tank. No leaks when parked up but after 10mins idle wet everywhere. Head Gasket done 600hrs ago, system not over pressurised.
Any particular places to look. TIA

 

[Warp Land Farmer]

Going to pull it apart to look closely tomorrow as not at all obvious where its coming from. Initially thought it was from the O ring between header tank and rad but doesn't appear to be.
Rad Core and inside of fan seem dry. Outside of fan very wet and thrown all up over header tank. No leaks when parked up but after 10mins idle wet everywhere. Head Gasket done 600hrs ago, system not over pressurised.
Any particular places to look. TIA

Water pump gasket or water pump itself. Just done one exactly as you describe.

 

[Flat 10]

Water pump gasket or water pump itself. Just done one exactly as you describe.

Done them either just before or just after the HG as the over pressure normally makes them go so not expecting them to be any problem.....

 

[solo]

6800 here weeps coolant around the header tank when hot. Done the seal a couple of times but I wonder if the plastic has distorted and I need a new plastic header tank. It doesn't leak until working hard. Maybe a split in header tank?

 

[Flat 10]

Took it all apart today couldn't find a leak. the header tank has gone weak where the rubber hose goes in (no leak but you can gouge with a finger nail) and the o ring on the stat on the bottom didn't seem to be correctly seated but that's all. Frustrating don't really want to chuck a new rad on (800 with adapters from NYTP to get one with a metal top and bottom). Was trying not to bother them but @Timbo @Phil P and @Tractortech any pearls of wisdom? If you could read my first post explaining the problem this will make more sense.

 

[Tractordave]

If you can get or borrow a pressure tester you can use the little hand pump to add a bit of pressure to the system with the engine shut off. Then any leaks are much easier to find. They normally need a little bit of pressure to Show themselves. I bought a nice Sykes one years ago and used it so much just for this problem... Don’t go throwing money at a new rad unless you’re sure...

 

[Flat 10]

If you can get or borrow a pressure tester you can use the little hand pump to add a bit of pressure to the system with the engine shut off. Then any leaks are much easier to find. They normally need a little bit of pressure to Show themselves. I bought a nice Sykes one years ago and used it so much just for this problem... Don’t go throwing money at a new rad unless you’re sure...

I ought to get myself one of them

 

[Phil P]

Took it all apart today couldn't find a leak. the header tank has gone weak where the rubber hose goes in (no leak but you can gouge with a finger nail) and the o ring on the stat on the bottom didn't seem to be correctly seated but that's all. Frustrating don't really want to chuck a new rad on (800 with adapters from NYTP to get one with a metal top and bottom). Was trying not to bother them but @Timbo @Phil P and @Tractortech any pearls of wisdom? If you could read my first post explaining the problem this will make more sense.

As @Tractordave says, best to get or borrow a pressure tester then you can check for leaks with engine stopped. It’s also a lot safer than looking around with the fan spinning!
The core usually rots around the bottom where dirt lies, I’m guessing you still have the plastic end caps on your rad? It’s done well to last this long if it is!
Check the bolts that hold the tray down that the rad and battery sit on are also tight. The two bolts just under the fan cowl can come lose and allow the whole fron to flex which causes the rad to crack.
The plastic end caps are well known for leaks though.

 

[Tractortech]

Now Then..
I read your plight this morning.. Have you got the early radiator with plastic top and bottom??
As mentioned, if you do, just bin it. Last time I priced a genuine radiator it was around £800 on a stock order.

 

[Phil P]

@Flat 10 if you need a rad find your local Behr agent, I usually pay £650 for 20 series rads which last time I spoke to Nick Young was cheaper than they could get them for. You’ll need the part number for the new type rad (AL176362) but you’ll still need a mod kit from Nick or dealer, don’t think there’s any difference in price.

 

[Flat 10]

Now Then..
I read your plight this morning.. Have you got the early radiator with plastic top and bottom??
As mentioned, if you do, just bin it. Last time I priced a genuine radiator it was around £800 on a stock order.

I was quoted £900ish on stock order. Yes it’s a plastic top and bottom. Lasted a fair while . Thanks for help

 

[Flat 10]

Ok so I have a rad and the adapter kit courtesy of NYTP. Now i am thick but where does the threaded end of the separate thermostat go? Previous one was in the bottom of the radiator and i assumed this screwed into the radiator but there's no threaded place to take it IFSWIM?

 

[Tractortech]

Call NYTP ????

Anyway, it's usually item 6 if it's the same as a proper John Deere set up..

 

[Flat 10]

Thank you. I assume my engine has a hose nipple screwed on there?

 

[Tractortech]

Correct

 

[Sierra Lama]

Hi, apologies for hijacking this thread. A few days ago the warning light came on on our 08 JD 6330 (2600HRS) I noticed that the coolant level was low, so I duly topped it up with coolgaurd and have been keeping a close eye on it. All seemed well enough no leaks to speak of then this morning after a cold night I started it and left it warm up, I noticed leaking coolant from around the top of the rad area, possibly from the bottom of the expansion tank area but hard to tell. Is it likely to be the O rings that have been spoke of here? It seems to stop when warmed up and also strange it hadn't done it starting from cold other mornings.

 

[Timbo]

Hi, apologies for hijacking this thread. A few days ago the warning light came on on our 08 JD 6330 (2600HRS) I noticed that the coolant level was low, so I duly topped it up with coolgaurd and have been keeping a close eye on it. All seemed well enough no leaks to speak of then this morning after a cold night I started it and left it warm up, I noticed leaking coolant from around the top of the rad area, possibly from the bottom of the expansion tank area but hard to tell. Is it likely to be the O rings that have been spoke of here? It seems to stop when warmed up and also strange it hadn't done it starting from cold other mornings.

Yes.

 

[Toddney]

Hi there same as above sorry to hijack the thread but I’ve a 2002 6520 with 9700hrs, in the last couple of days she’s blowing coolant out of the rad cap, the oil is clean and so is the coolant and she runs sweet as a nut so am hoping it’s not a head gasket!!, I’ve swapped the cap for a new one has made no difference at all, have tested the thermostats one seems a little jumpy to open but does open and the other is fine, just wondering if anyone had any ideas before I have to start digging deeper

 

[Flat 10]

Likely combustion gases pressurising the coolant? Sorry. I’m no expert but I think you can buy a “sniff” test that you dip in the coolant to test for exhaust gases. Mine was HG and had the symptoms you describe.

 

[Toddney]

Ok mate thanks for coming back to me I’ll see if I can get one and go from there