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Old 03-14-2017, 11:14 AM   #1
mister.freeze
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disappearing water

I’m losing about a gallon of water a day. No steam from the exhaust, or water in the oil pan. I’ve changed the oil twice looking for water because I have chocolate pudding in the valve covers. I probably have a bad condensation problem; live in Houston AND my commute is 11.2 miles, so it never gets very hot. Dual electric fans have always kept it cool in the summer, and are probably not letting it heat up all the way on my short commute. After a 1-way trip, I have to put in about half a gallon of water before heading back. I’ve already resealed the intake manifold after finding some oil in the radiator (needs a good flush now) and UV leak detector indicates no leaks. Nothing on the driveway or any dips in the parking lot. Where is the water going? I thought it might be the cause of the chocolate pudding, but without water in the oil pan, I figured it was just condensation. The overflow tank doesn’t overflow, and the system will keep pressure overnight. The engine runs fine, especially after a long warmup. I took the heater core out and just looped the hose back to the water pump. Any ideas? I’m having the motor pulled and resealed in a couple of weeks for oil leaks, so if it’s a bad head or intake gasket, it should be fixed, but I have no more symptoms than the disappearing water, which leads to overheating.
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Old 03-14-2017, 12:13 PM   #2
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Re: disappearing water

You might have a pinhole in the radiator or crack in the hose. Sometimes leaks only happen under pressure when the system gets hot.
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Old 03-14-2017, 12:30 PM   #3
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Re: disappearing water

No evidence via UV dye. System holds pressure: doesn't leak down. Plenty of stop-leak in the system too.
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Old 03-14-2017, 11:47 PM   #4
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Re: disappearing water

I've heard that stop leak isn't the best to use. Gums things up. The water has to be going somewhere and as much as you are saying is disappearing would make the oil milky if it was head/intake gasket related. Check the transmission if it's an auto, maybe it's escaping through the cooler lines.
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Old 03-15-2017, 06:34 AM   #5
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Re: disappearing water

Hmm. Hadn't thought about the transmission. I'll check
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Old 03-15-2017, 08:17 AM   #6
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Re: disappearing water

Had a bad radiator cap that would let loose going down the road. Replaced the cap and had no more issues. Cheap place to start anyway.

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Old 03-15-2017, 12:26 PM   #7
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Re: disappearing water

i have had that happen w/ loosing water in the cooling system.

came to find out it was a head gasket was the cause of it ..
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Old 03-15-2017, 02:55 PM   #8
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Re: disappearing water

Do a pressure test of the cooling system, and let it sit under pressure overnight.
Also ,if you are losing coolant from a head gasket, check your plugs, or better yet, the top of the pistons. If you have one real clean plug or a clean piston top compared to the others, that will be an indication of a leak.
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Old 03-15-2017, 03:08 PM   #9
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Re: disappearing water

I would say you have a bad head gasket and are burning it up out the tail pipe. If that is so you could (if not already) be scoring up cylinder walls. The chocolate pudding you are seeing is not just a little condensation, could be a big problem.
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Old 03-15-2017, 04:58 PM   #10
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Re: disappearing water

When you get the problem solved, I would leave early for work and take the long way. I had a TR-6 that always had condensation under the oil fill cap, until I started to put miles on it
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Old 03-15-2017, 10:03 PM   #11
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Re: disappearing water

I've lost a lot of water through a bad head gasket without noticeable steam coming out the exhaust. It takes a massive head gasket failure to make a trail of steam behind you.
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Old 03-16-2017, 03:03 AM   #12
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Re: disappearing water

Quote:
Originally Posted by BBrendal View Post
I would say you have a bad head gasket and are burning it up out the tail pipe. If that is so you could (if not already) be scoring up cylinder walls. The chocolate pudding you are seeing is not just a little condensation, could be a big problem.
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Old 03-18-2017, 06:32 PM   #13
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Re: disappearing water

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Originally Posted by Blazerowner View Post
I've heard that stop leak isn't the best to use. Gums things up. The water has to be going somewhere and as much as you are saying is disappearing would make the oil milky if it was head/intake gasket related. Check the transmission if it's an auto, maybe it's escaping through the cooler lines.
Nothing in the transmission
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Old 03-18-2017, 06:34 PM   #14
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Re: disappearing water

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Originally Posted by richard2717 View Post
Had a bad radiator cap that would let loose going down the road. Replaced the cap and had no more issues. Cheap place to start anyway.

Richard
Cap is fairly new. Overflow tank never seems to get any fuller, and the system will stay pressurized overnight.
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Old 03-18-2017, 06:36 PM   #15
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Re: disappearing water

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Originally Posted by hemi43 View Post
Do a pressure test of the cooling system, and let it sit under pressure overnight.
Also ,if you are losing coolant from a head gasket, check your plugs, or better yet, the top of the pistons. If you have one real clean plug or a clean piston top compared to the others, that will be an indication of a leak.
The system will hold pressure overnight. I often release it to add water for the morning commute. Holding pressure doesn't jive with a gasket leak.
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Old 03-18-2017, 06:41 PM   #16
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Re: disappearing water

weird, can't think of anything else, w/o putting a scope down the spark plug holes to see what the top of the pistons look like. what do the spark plugs look like?

Maybe drop down to the engine gurus section, they may have an idea

OOps, sorry! just read hemis post
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Old 03-18-2017, 08:19 PM   #17
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Re: disappearing water

I need to pull the plugs, but can't right now (abdominal surgery). True dual exhaust, tho, and similar results in the mornings out of both sides. Just praying it holds together 2 more weeks...
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Old 03-18-2017, 09:06 PM   #18
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Re: disappearing water

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Originally Posted by mister.freeze View Post
I need to pull the plugs, but can't right now (abdominal surgery). True dual exhaust, tho, and similar results in the mornings out of both sides. Just praying it holds together 2 more weeks...
that sux, get well soon! we need to put this mystery to bed
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Old 03-19-2017, 12:14 PM   #19
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Re: disappearing water

Really sounds like the head has hair line crack probably at an exhaust seat or between 3-5 or 2-4. Pay close attention to the passenger if on driver side normally number 3.
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Old 03-19-2017, 03:31 PM   #20
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Re: disappearing water

We'll see when the motor gets new gaskets the weekend of 1Apr...
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Old 03-19-2017, 08:57 PM   #21
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Re: disappearing water

Check for water on the floor after siting all night. I found a leak simular that came from the intake manifold and itleaked down the back of the block where the trannsmission separate .
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Old 03-19-2017, 09:38 PM   #22
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Re: disappearing water

Even though I reseald the intake manifold, I'm not confident because My torque wrench was too big and I doubt it's all torqued down enough. My best guess is the front crossover passage leaking into the valve covers
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Old 03-19-2017, 10:10 PM   #23
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Re: disappearing water

When you have the motor pulled I would pull the heads to have the heads crack checked, checked for flatness, resurfaced, and a good valve job. If those are factory heads they are prone to cracking and have soft valve seats.
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Old 04-01-2017, 05:50 PM   #24
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Re: disappearing water

#3 has a broken piston and cracked cylinder. Mystery solved.
Anybody got a short block for cheap in Houston?
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Old 04-01-2017, 09:05 PM   #25
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Re: disappearing water

I have a long block 1994 Chevrolet 350 it was pumping oil on the number 3 cylinder I pulled the pan and the Piston is bad on that but it did not hurt the cylinder wall. If interested send me a PM I'm in Conroe.
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