Need recomendations please

[R.O.R-2.0]

plastic impeller in the pump? slipping? should be flowing whenever the engine is running..

only thing i can think of causing it to stop flow, is a decently bad head gasket, or a bad water pump..

[nathan_b]

or a bad thermostat, or clogged radiator

[R.O.R-2.0]

or a bad thermostat, or clogged radiator

you can solder a t-stat closed, and the pisser system will still work.. same with a clogged rad core..

i was talking about the pisser stopping at idle..

[BigVWman]

I'd second the either bad HG(most probable) or plastic impeller! HG can be leaking combustion under load, maybe check and see if hoses get rock hard, when warm they are hard but when hg is loosing combustion gases they get rock hard! we have also had a cracked impeller work fine until its under load and then slip, although i haven't seen many with the plastic impeller on external pump, usually more common with later internal pump motors!

[RustyToy]

Ok, sorry for the delay in getting back to follow up.

I guess I need to clarify. Even at idle I have water circulating into the res. The hole I was referring to is the one that lets excess coolant exit the system and dump onto the ground. Fluid rises to a certain point in the res and then flows through a chanel molded into the res and exits via a small opening just below the cap.

The water pump is brand new, the T-stat is brand new.

After giving the head bolts their final 90* I stopped seeing and smelling engine gases (exhaust?) exiting the res. I do get steam but that kind of expected.

I thought about an air pocket trapped in the heater core. That would explain why one of the hoses going into it was hot and the one returning from it was cold. I also wondered about whether I had a coolant line collapsing at highway speed not allowing water to circulate.

I'll tell ya what though, a person never really appreciates the fantastic mileage they get from their little VW Diesel till they spend a few weeks commuting a hundred miles a day in a 17mpg Jeep.

[ORCoaster]

Yeah, we do get spoiled on the fuel use don't we.  I had to drive my Ranger last week and was wondering what the heck is up with that fuel gauge?  I have gone about 140 miles and it is near half tank already.  The VW goes that far before it gets off the full side.  I also have one of those Scan Gauge displays in the Ranger.  Watching the cost of the trip creep into the 70 dollar zone was disheartening.  I can drive a long way on that much diesel.  So, I worked extra hard to make the VW get up and going yesterday after work.  Phew, back to double mileage again.

[RustyToy]

Well I messed with it some more this evening. Still don't feel like I'm getting anywhere. With the engine temp (factory guage) sitting between 1/2 & 3/4 there is steady vapor coming from the vent on the res. If I rev it to rediculous RPMs I've still got vapor but thats it, and the top hose really doesn't feel "rock hard". Not hard to squeeze at all actually.

As soon as I let off the throttle though it starts spitting out the vent on the res. You can tell there's some pressure there. After over an hour of sitting in the shop running, some at idle and some at high rpms, the temp never did get over 205*

[8v-of-fury]

It pukes coolant out the reservoir overflow when you let off the throttle? That doesn't make sense. This is with the cap on and idling hot or off and idling hot?

If you let it sit and start it up without the cap on what happens? No more bubbly bubbly, but still have a cold coolant tube? I would say to pull one of the heater core hoses and pressure feed water through it.. ie a garden hose. Or a gravity feed of coolant? I dunno. I use the hose for mine.

The top hose shouldn't be ROCK hard, the coolant system is only pressurized to 11-13psi. That isn't really too much and should be squeezable, if they are it says the combustion gases are NOT leaking anymore .

So you most certainly have an air lock though, and that needs to be dealt with first before anything else can be determined.

[ORCoaster]

At this point I think I would be pulling both heater hoses and flushing it from both sides.  Kind of a scrubber effect in case something is lodged in there.  I would start with lower pressure first to simulate the water pump and system pressures.  Then crank it up to house pressure, usually about 40 psi.  This just isn't right, bubbling after rev then idle. 

[RustyToy]

When it pukes out when I let go of the throttle it is with the cap on. Oh hell, it does it with the cap off as well but pisses out the vent hole when the cap is on. This is with the engine hot.

When I was messing with it earlier today I noticed that one of the lines going to the heater core had a slight kink in the rubber portion. I didn't think the kink was enough to stop coolant flow but once I straightened everything out to where the kink was gone the heater now blows hot. If you remember, earlier I had the issue of factory guage showing hot and aftermarket ( which is mounted in the heater hose running from core to pump ) reading zilch and the heater not blowing hot air. Well, now I have hot heater and a good reading on the heater line temp. I guess I should have mentioned that earlier that now all my hoses are getting warm.

When I start the engine with the cap off I can look inside and see coolant circulating. It swirls around and sucks down to the bottom then comes up again, then sucks down and back up again. It just keeps repeating that cycle till I grab the throttle and rev the engine. When I initially rev it, it will suck down then come up to a certain level ( always the same ) and hold at that level till I let go of the throttle. Then suck down....wait for it.....and then surge a bit out the top. We're not talking quarts here, we're talking maybe a 1/8 cup at the most each time.

It's actually doing better than it was. The puking coolant was much worse before I unkinked the heater hose.Tomorrow when I get home I'll check coolant level and if it's good I'll take it down to the highway and make another run up that long steep grade again and see what it does.

To be honest, nothing about this makes sense at this point. It's got me stumped. I need ideas. I'm actually thinking I may video the coolant res from a dead cold start and post it somewhere. Maybe if you all are seeing what I'm seeing something will jump out at you that isn't jumping at me.

I did think i saw something crawling around on the steering rack this evening though...I'm thinking it might have been a gremlin laughing at me.

[RustyToy]

ok, I threw 3 videos up on YouTube.
1. About 45 seconds after I started the car.
http://www.youtube.com/watch?v=xB4ky87sz_U

2. Revved it up and then let off the throttle.
http://www.youtube.com/watch?v=By9NxMsHPQg

3. took it for about a 3 mile drive.
http://www.youtube.com/watch?v=tkIZ6c_6uPs

About 1.5 miles into the drive the temp guage went up a bit but the temp on the heater core strted dropping. I might mention that at about that time I caught a whiff of coolant.

[burn_your_money]

When I start the engine with the cap off I can look inside and see coolant circulating. It swirls around and sucks down to the bottom then comes up again, then sucks down and back up again. It just keeps repeating that cycle till I grab the throttle and rev the engine. When I initially rev it, it will suck down then come up to a certain level ( always the same ) and hold at that level till I let go of the throttle. Then suck down....wait for it.....and then surge a bit out the top. We're not talking quarts here, we're talking maybe a 1/8 cup at the most each time.

That sounds normal to me.

I would try a new coolant bottle and cap, or at least test the cap and bottle. (sorry if I missed that if you did it)

[RustyToy]

Burn-your_money, you may have just hit the nail on the head. Tonight I put a thick rubber gasket on the res lid to ensure that i was in fact getting a good seal. The gasket was wide enough though that it would prevent any fluid or gases escaping the res from passing through the vent in the cap and thus into the drain on the side.

Even though that was all sealed up I was still getting steam from the drain in the side of the res and when i revved the engine I got coolant squirting out the drain on the side.

Maybe I'm wrong but that's kind of leading me to believe that there is some sort of internal failure in whatever it is that seperates the expansion chamber from the drain. Allowing nearly constant loss of coolant to one degree or another. Which would mean that it's also not capable of pressurizing the system correctly. Allowing for a lower boiling point of the coolant.

Am I crazy?  (Probably, but that's not what we're here to discuss.)
is it feasable? my tiny brain is saying yes.

[R.O.R-2.0]

Burn-your_money, you may have just hit the nail on the head. Tonight I put a thick rubber gasket on the res lid to ensure that i was in fact getting a good seal. The gasket was wide enough though that it would prevent any fluid or gases escaping the res from passing through the vent in the cap and thus into the drain on the side.

Even though that was all sealed up I was still getting steam from the drain in the side of the res and when i revved the engine I got coolant squirting out the drain on the side.

Maybe I'm wrong but that's kind of leading me to believe that there is some sort of internal failure in whatever it is that seperates the expansion chamber from the drain. Allowing nearly constant loss of coolant to one degree or another. Which would mean that it's also not capable of pressurizing the system correctly. Allowing for a lower boiling point of the coolant.

Am I crazy?  (Probably, but that's not what we're here to discuss.)
is it feasable? my tiny brain is saying yes.

i would start digging a little deeper with that issue. i believe you are on the right path.. ive never even had an expansion tank puke before. i wasnt even aware they had a vent until i read your thread..

i would start by replacing, or atleast checking out the cap. you can pull the guts out of the cap, both valves are on a disk that sits inside the cap.

take that disk out and make sure both valves seal, because they should..

[RustyToy]

I've got a new cap and a new expansion tank enroute. Should be here Monday (if UPS can find my house). Less than $30 for both pieces. small price to pay i think.