Coolant LEAK but only when COLD!

cags005 · Post by **cags005** » Sat May 27, 2017 5:35 pm

Further to my previous post ....

I came out to my van in the morning and discovered a significant coolant leak. Try to ignore the fact that the leak looks like boobs

: CoolantLeak.jpg (77.71 KiB) Viewed 8575 times

Oil level is fine. Transmission fluid is fine, brake fluid is fine. Coolant in radiator is good, but the coolant in the expansion tank is low.

I drove the van and it does not overheat and drives perfectly well. Park somewhere for half an hour or so and come out ... NO leak. Come home and park the van overnight and bam .... leak.

Any ideas?

204explorer · Post by **204explorer** » Sat May 27, 2017 6:27 pm

Cooland leaks show up more often when the system is cold. Where I live it gets really cold and in the winter coolant leaks are common. Parts shrink when they cool down and the leaks show up. Coolent recovery tanks are prone to leak on our vans. The plastic material is 25 plus years old and went trough 1000's of hot/cold cycles.
Please dont use any leak stop. This stuff was developed by the devil himself[emoji6]

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cags005 · Post by **cags005** » Sat May 27, 2017 6:38 pm

Thanks for the reply! I pulled the coolant tank out and it seemed all good .... no leaks there so I suspect it may be a hose (I hope). I have an appointment with Rising Sun Auto on June 6 and I'm crossing my fingers it's nothing to terribly expensive!

Morgonzo · Post by **Morgonzo** » Mon May 29, 2017 6:16 pm

Just in case it IS a crack/leak in the expansion tank, I've had good luck using P.O.R 15 Epoxy putty to seal up the crack. I've confirmed with the company that it's non-reactive with coolant and would not get into the system. A lot cheaper than buying a new tank.

just my 2.5 cents worth.
Cheers.

sealica · Post by **sealica** » Mon May 29, 2017 8:49 pm

I was pricing out expansion tanks on Amayama because mine was really, really, really dirty with Sludge. They were $25-35 USD so if you were also grabbing some other parts, with shipping it's not too expensive!

I cleaned my tank instead because it's not leaking, but also awesome tip with the POR-15 putty - love that stuff!

tomaboyd · Post by **tomaboyd** » Tue May 30, 2017 7:34 am

I had the same issue. Mine turned out to be the head gasket.

Post by **Growlerbearnz** » Tue May 30, 2017 2:18 pm

Could you confirm a couple for things for us?

-Is the coolant in your radiator red? (not green)
-Where was the paper towel placed- under the front or the rear of the engine, or the passenger or drivers side?

cags005 wrote:
CoolantLeak.jpg
Coolant in radiator is good...

I notice the oil is concentric with the coolant, which suggests they're dripping from the same spot, which rules out the expansion tank (there's no oil near the expansion tank). There's not too many places where an oil and a coolant leak come out at the same place. I'd guess the paper towel was under the alternator (drivers side of engine) or rear of engine/bellhousing.

The "coolant" almost looks like transmission fluid from the way it's separated, and the way the oil looks like it's dissolved into it a bit.

Post by **Growlerbearnz** » Fri Jun 02, 2017 10:17 pm

Since I just found this photo, here's what a coolant leak from the water pump area looks like:

: LEak.JPG (48.71 KiB) Viewed 8468 times

This is taken from the rear of the engine, just below the exhaust pipe, looking forwards. The two pipes are transmission cooler lines.

cags005 · Post by **cags005** » Sat Jun 10, 2017 6:26 pm

Well I (with the help of a buddy) located the coolant leak problem and Growlerbearnz you were right ..... it's the water pump! Super happy to know what the problem is!

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Post by **Growlerbearnz** » Sat Jun 10, 2017 10:08 pm

Awesome(ish). So much cheaper to fix than pulling the whole engine for a frost plug. Along with the water pump you'll want to change the thermostat, and the little O-ring on steel pipe at the back of the pump.

Normally you'd also replace the timing belts, tensioners, and crankshaft seal just because they're a pain to get to, but I think your timing belts were changed fairly recently?

cags005 · Post by **cags005** » Sun Jun 11, 2017 1:57 pm

I'm thinking I may as well change out the timing belts at the same time. Is it a difficult job? I have a mechanic friend who has worked on Diesel engines before but not a Delica and he is willing to tackle it with me.

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Post by **Growlerbearnz** » Sun Jun 11, 2017 3:03 pm

Replacing the water pump is fairly straightforward and there's nothing wacky about our engine, but there are a lot of things to remove to get to the pump.

Download "the engine cooling manual" from here: http://www.delica.ca/forum/viewtopic.php?f=17&t=7336, which has instructions for replacing the water pump. Though one of the instructions is "Timing belt removal , refer to group 11", which is in "4G7 & 4D5 Engine Manuals" from here: http://www.delica.ca/forum/viewtopic.php?f=17&t=7335, you'll need section 11B-26 "Timing belt and timing belt B" to remove the timing belts.

Also check out Tojo's awesome thread "L300 head replacement and timing belt DIY" here http://www.delica.ca/forum/viewtopic.php?f=6&t=16587 but remember that he's replacing the entire head, so there are a lot of steps he does that aren't necessary for a water pump replacement. Follow the workshop manual, but refer to Tojo's pictures if (when) you get stuck.

cags005 · Post by **cags005** » Mon Jun 12, 2017 4:57 am

Thanks!

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cags005 · Post by **cags005** » Tue Jun 13, 2017 10:59 pm

The engine cooling manual link doesn't seem to work.

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Post by **Growlerbearnz** » Wed Jun 14, 2017 12:25 am

Hmm. It works for me. Try it again, maybe from a different device?