Coolant Issues

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Lanval
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Coolant Issues

Post by Lanval » Sun May 31, 2015 11:36 pm

4 recent experiences suggested I take a look at things. All of these within the last two weeks... in this order:

1. Coolant was low, but hadn't checked it in months. Filled. Two weeks later, low again (by low, I mean below the minimum line in the overflow coolant container with a cold engine)

2. In the AM when I take off, I drive for about 30 seconds and then hit a stoplight. Several times recently have been able to smell coolant while at that light.

3. Engine heating/cooling dynamic has changed substantially. This engine usually is slow to fully heat up, and quick to cool down when driving. Now heats up quickly, doesn't significantly cool when driving. Stays at/near center mark once hot (this is unusual. Unless its 100 degrees, driving around town will keep the coolant marker between cold and the red light in the middle of the coolant gauge.) There did not seem to be any overheating.

4. A quick look under the rear showed me a whitish spot on the exhaust pipe, under the driver's side head.

********************

Since the coolant is disappearing, and I have yet to see oil mixed with coolant, or white clouds from the exhaust, I went looking for a leak, expecting to see something from the area on the driver's side. Here are my pictures:

The little coolant reflow (I can't remember exactly what it's called) line is apparently leaking at both ends:

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and

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I thought this might account for this little bit of coolant on top of the driver's side head:
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Here's the exhaust with coolant actually dripping off. First time I've seen that. It's been sitting for 24hours plus at this point.
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Here's where I think the coolant is coming from; this is the front corner of the driver's side head, looking towards the back of the engine/van (not you can see the oil filter which is at the rear of the van in the background):
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This is the side of the head just above that corner with the drop. Looks dry up here:
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Some corrosion down here ~ I think that plug with all the white around it is the temperature sensor for the coolant. That may explain the odd temperature readings. Not wet enough to account for my leak, but needs to be dealt with nonetheless:

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Here's the other side of that same corroded area; it's harder to tell here, but there is more corrosion at the end of this pipe where the plug is; also, the difference in darkness of the coolant pipe (darker towards the bottom of the picture) makes me think it's leaking there too, or will be soon:
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***********************

Well, after getting all these pix, I put the AC back in place, so I could idle the engine and see how much coolant was coming out and where. I started the engine up, and took a couple of videos (see the "unusual sound" thread) and then got under the car. At that point, I realized I was in deeper than I wanted to be. There was a steady stream of fuel coming off the driver's side rail and dropping onto the rapidly heating exhaust pipe.

I hopped up and turned off the engine. I suspect that in wrangling the AC compressor off, I must have knocked the fuel rail about a bit, and caused old fuel line to crack. I reason this, because in the minute or so of idling, there was a pool of fuel about the size of a dollar bill on the ground. Were it leaking that much before, I would long since have been conflagrated. So; until I can replace all the fuel lines (might as well do them all at this point) I can't go further on the coolant leak.

Once I've resolved the fuel line issue, I'll see what happens while idling the engine. In the meantime I'll also replace that top line ~ easy to get at, and doesn't require draining the coolant if I recall correctly. All in all though, I think that head is coming off when Colin comes to visit. Let us see what happens.

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Amskeptic
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Re: Coolant Issues

Post by Amskeptic » Mon Jun 01, 2015 4:29 am

Lanval wrote: 3. Engine heating/cooling dynamic has changed substantially. All in all though, I think that head is coming off when Colin comes to visit. Let us see what happens.
Your thermostat has the same requirement as our air-cooled engines, to get the engine warmed up, so that the operating clamping forces are achieved as quickly as possible.

If you have had slow warm ups in the past, this can exacerbate potential head leaks.
Can you retorque the heads?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

Lanval
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Re: Coolant Issues

Post by Lanval » Mon Jun 01, 2015 10:09 pm

Amskeptic wrote:Can you retorque the heads?
Colin
I will check it tomorrow when I go after the the FI leak. I'm pretty sure I have some BMW fuel line left over from when we did the gas tank (2 years ago?); if it's still supple, I'll use that. Probably do the heads first.

Are you OK with the values that Ben gives for the heads (sequence and measurements)?

http://www.benplace.com/head.htm -> scroll to the bottom

"Torque sequence:
Step1: Coat surface of cap nut with sealant.

Step2: Torque to 10NM (7 ft lb)

Step 3: Torque to 50nm (37 ft lb)"

L

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Amskeptic
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Re: Coolant Issues

Post by Amskeptic » Wed Jun 03, 2015 7:45 am

Lanval wrote:
Amskeptic wrote:Can you retorque the heads?
Colin
I will check it tomorrow when I go after the the FI leak. I'm pretty sure I have some BMW fuel line left over from when we did the gas tank (2 years ago?); if it's still supple, I'll use that. Probably do the heads first.

Are you OK with the values that Ben gives for the heads (sequence and measurements)?

http://www.benplace.com/head.htm -> scroll to the bottom

"Torque sequence:
Step1: Coat surface of cap nut with sealant.

Step2: Torque to 10NM (7 ft lb)

Step 3: Torque to 50nm (37 ft lb)"

L
Go one at a time using the final sequence 37 only! You are already clamped up, no need to do the first-stage "bedding in the push rod tubes" procedure. Yay, right?

I would also clamp the hoses leading to the heads and remove the drain screws (or drain the engine coolant entirely) before doing this procedure, although you can skate through if you work efficiently.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

Lanval
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Re: Coolant Issues

Post by Lanval » Wed Jun 03, 2015 8:46 am

Amskeptic wrote: I would also clamp the hoses leading to the heads and remove the drain screws (or drain the engine coolant entirely) before doing this procedure, although you can skate through if you work efficiently.
Colin
Can you explain that in a bit more detail? Is it your concern that leaving the coolant in will possibly result in more/additional leakage due to inconsistencies in pressure across the head? By efficient, do you mean "quickly"?

If possible I want to avoid draining the coolant, but maybe it's time. Dunno. If we go that far, why not just take the head off, and reseal with a gasket and a shit-ton of sealant? ('cause I know that last part will drive you crazy...)

Two comments:
I'm getting my ass handed to me by life on a daily basis at this point. Just trying to keep up, so not sure when I can do this. I have the fuel line to do the rails, but doubt if it's enough to do the lines from the firewall to the rails. If the current line still looks good, then I'll do the fuel in a day or two and try to do the head this weekend.

I also think I will need a new, smaller torque wrench to fit in that area and work, as you say, "efficiently".

Check in from time-to-time, but I'm trying to do this in the interstitial moments of 16 hour days at this point, while working with somewhere between 1 and 0 cars. (Volvo having some issues I can't handle).

Thanks,

L

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Amskeptic
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Re: Coolant Issues

Post by Amskeptic » Wed Jun 03, 2015 5:12 pm

Lanval wrote:
Amskeptic wrote: I would also clamp the hoses leading to the heads and remove the drain screws (or drain the engine coolant entirely) before doing this procedure, although you can skate through if you work efficiently.
Colin
Can you explain that in a bit more detail?
Just knock it out. Zip a nut / washer off, smear it / them with sealant, slap it back on and zip it up to 37 or heck, take 40 ft/lbs. Go in the final sequence. Git 'er done before life hands you another . . .
Colin :cyclopsani:
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

ainokea
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Re: Coolant Issues

Post by ainokea » Fri Apr 08, 2016 8:22 pm

The most effective method of finding a coolant leak is with a pressure pump. Put 15 - 18 lbs. psi pressure in the system at the fill jug wait for a few minutes to allow the gauge to settle, then inspect from both sides of the engine all the way up to the radiator. There is a lot of plumbing on a vanagon but from the photos, I would guess that head is leaking under pressure when warm. Sometimes a re-torque helps but not all the time as the head seal or gasket is rather flimsy and yours looks like it was changed before. Another useful purpose of a pressure pump when bleeding a vanagon cooling system, is to fill the jug normally, connect the pump and open the radiator bleeder. Pressureizing will push trapped air in the plumbing up to the radiator and out through the bleeder filling it with coolant making bleed time significantly shorter. You will need the correct adaptor for the jug to fit the pump. Another tip I would add is, if the head is removed, clean the seals mating surface and eliminate any sharp edges that could damage the seal when installing and torquing. Ainokea

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