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Sun Apr 06, 2008 9:20 am

So the story goes like this:

1984 Westy, stock 1.9, 133,000 miles.
Massive coolant leak out of the bottom of the engine (not dripping, but literally pissing coolant). Mechanic said he welded up a hole to the water jacket made by previous owner attempting to fix something else.
Repair held for a few weeks, then dripping coolant. Head gaskets replaced, repair did not hold, told by mechanic there is a crack in the passenger side head, negotiated free labor to replace both heads. Repair held for a couple of weeks, drove the van on a 600 mile trip, no leaking coolant, no burning coolant smell. Then two days later return from a short trip to the store, after 10 minutes of being parked-massive puddle of coolant under the van. Was not leaking before parking it. Coolant is literally pissing out again, collecting on the passenger side exhaust support bracket bolt before hitting the ground. I cannot locate the leak, but when I squeeze either of the large rubber hoses running along the firewall, coolant comes pissing out again immediately and I can hear a gurgling sound. Not a little bit, but a major leak. Mechanic says a hose probably blew, but I cannot locate a leaking hose and the coolant seems to be coming from behind the tin protecting the push rod tubes on the passenger sides. I can't imagine the head gaskets blew again, too sudden and too much coolant loss. Any ideas? :evil: :(

Sun Apr 06, 2008 9:22 am

If coolant is peeing out of the engine how is it that you can't locate the leak?

Andrew

Sun Apr 06, 2008 9:40 am

Because it seems to be coming from behind the tin pieces protecting the push rod tubes at the front of the engine. To crawl under there right now would mean to swim through an ocean of coolant. I will have my answer soon enough I suppose, just looking for some ideas given the scenario and the fact that I may be facing another round of negotiations with the mechanic.

Sun Apr 06, 2008 11:51 am

Let engine cool.
Remove tin.
Definitively locate source of leak.
Find new mechanic.

Tue Apr 08, 2008 12:42 pm

Well, mechanic claims the passenger side gasket blew at the front of the engine. Claims that about one in twenty vanagons will repeatedly blow gaskets like mine. They will not warranty this repair (because it is the nature of the beast). They claim the cooling system is "overpressurizing itself" for some reason and they cannot figure out why, without taking the head off again. They say the first thing they recommend on Vanagons is a Tiico conversion for this very reason.

I have had a vanagon and been on these boards for 4 years and have never heard of gasket failure after less than 1000 of driving. Does this make any sense? This is a VW specialist that occasionally does business on this site and advertises an exclusive process to replace gaskets. :evil:

Tue Apr 08, 2008 1:06 pm

funagon wrote: Let engine cool.
Remove tin.
Definitively locate source of leak.
Find new mechanic.

That last part again ~ FIND A NEW MECHANIC.

I had a fair amount of work done by a mechanic locally; he's a good guy and seems to know his stuff, but I had problems with his work. Here's why, I think:

He was my age (40's) and always had a couple of really nice resto jobs in his shop. The other guys were too young to really know air-cooled (early 20's). Whenever I went to the shop, the younger guys were working on my van, and being (occasionally) directed from afar; the top guy was always working on the restos.

My guess ~ he's the one who really knows air-cooleds, and he spends his time on the jobs he likes/gets well paid for. My van didn't rate the kid glove treatment.

So, eventually I came here, got a recommendation, and have been seriously happy/impressed by the quality of the work I'm getting for the money I pay.

I ain't rich, but sometimes it's more realistic for me to pay someone else to do it. At those times, I want it done right, the first time. Your guy doesn't sound like he's getting it done the first time. It sounds like he's setting you up for:

1) A lot of repeat business
2) An expensive upgrade to his "special process"
3) An even more expensive rebuild using his "special process"

I'll conclude with this question:

If you give money to someone to do something, and they don't do it, or do a poor job, why would keep giving them money?

He might be honest, but I'd still be thinking about moving on.

Best of luck,

Lanval

Tue Apr 08, 2008 1:25 pm

Yeah, I pretty much concluded that I was done with this operation for any future work after the first repair failed, but the problem is trying to get them to remedy their work. After their first gasket replacement failed almost immediately, they told me a head was cracked and I needed a new head. I told them that they should have told me that while they had the heads off and I would have told them to put new heads on and thus save the redundant labor. They agreed to eat the labor to put on the new heads, which is fine except I paid another $1100 for the parts (heads, gaskets, etc.) and in less than 1000 miles the repair has failed again. Now I am being told "its the nature of the beast" and 1 in 20 Vanagons will repeatedly blow gaskets like this. Seems to me like either the craftsmanship is shoddy or there is an underlying cooling system problem that was never addressed--and thus the original diagnosis about why it was leaking coolant was wrong or incomplete.

Here are some other things they have told me that I have to question:

1. Normally Vanagons will need to have their head gaskets replaced once every year or every other year. (Sounds like they are reusing a lot of heads that have been machined into oblivion and thus failing).

2. If you convert to a Subaru you are right back to an engine with head gasket problems. Is this true?

Tue Apr 08, 2008 1:57 pm

In response to your second question concerning Subaru engines. Yes, there was a model of the 2.5L from Subaru whose head gaskets would begin leaking coolant after a period of use. For instance, with my 2000 Outback, it developed that problem, the dealer tried the "additive" fix that was part of the recall, but later replaced the gaskets at no charge.

I believe that with a Subaru conversion, given a solidly rebuilt engine, you wouldn't run into the head gasket problem.

This is just my opinion concerning Subaru's.

hatchb4ck

Tue Apr 08, 2008 2:14 pm

Subaru: no.
I too have a subaru outback and I had the headgasket done at 120k.
But it's one specific engine. the 2.5 DOHC which can be find on specific models (outback and forester mainly) from 97 to 00. From memory that is. Also the new head gasket fixes the pb.

The DOHC is not recommanded, most favor other engine generations, espcially the 2.5 SOHC.
The 2.2 is highly regarded, any year. Most favor the 90-94/95 as it's an OBD1 engine, esp in california. But later ones are ok as well.

Some asked for the best bet recently: the 2.5 from 2001-2004 were the best bet. Recent (hence low mileage), easy to find, etc. has some electronics but it's doable.
The turbo engines are mainly discarded due to complexity (turbo relocation). Many sellers have some kits, such as vanaru.com

There is a newsgroup dedicated to such conversions (just need to register I think):
http://autos.groups.yahoo.com/group/subaruvanagon/messages
Do some reading, it comes up often.

Then go to Files then FAQ (first folder). Everything is there.
WHICH SUBARU ENGINE SHOULD I CHOOSE FOR MY VAN ??

This question gets asked over and over.

The most general answer is any Subaru engine will work in a Vanagon.

However, pass on the 1.8L engines from the pre-1990 GL Subaru and from the later model Imprezas. Although the late model Impreza 1.8L looks identical to the popular 2.2L, it doesn’t provide any power increase over a VW waterboxer...so why bother...even though reliability would be better..

The most popular Subaru engine, used in hundreds of successful conversions is the 2.2L 137hp SOHC available in the 90-94 Subaru Legacy.

Since these engines are now (in 2005) 11-15 years old, it seems natural to ask, “Why not use the later model engines?”

The popularity of the 2.2L engine is due to several factors: Price, availability, and a VERY STRONG ENDORSEMENT from Hobert Kennedy, of Kennedy Engineering (KEP)...who gave a huge boost to the popularity of the conversion by designing, manufacturing, and offering for sale most of the critical conversion parts needed for the transplant.

The fact that KEP is located in CA also provided a strong incentive for the use of the 2.2L.....

(At this point a little history is probably appropriate).
-------------------------------------------------------------

KEP is located in S. CA, that mecca of everything automobile, and was already in the business of making adapter plates and flywheels to mate almost any engine to VW transaxles for use in sand cars. Subaru engines had become popular subtitutes for VW engines in sand cars. Hobert also owned a Vanagon that he used in his business as a delivery and parts vehicle...... with the usual problems.

All he needed was a suitable air intake plumbing, a crossmember, a header, cat, and muffler.....a few plumbing parts from the local hardware store.....and.. as they say...”Voila....the SubaruVanagon conversion was born...and the parts were soon added to the KEP product list.

But Hobert also had to get his newly transformed van legal with the CA smog officials. In CA, all engine conversions have to pass our strict smog laws and comply with the engine change guidelines of our local air quality watchdog bureaucracy....affectionately know as "CARB" (California Air Resources Board). Compliance is tough. The simpler OBD-1 engine diagnostic system has fewer sensors, tests and generates fewer error codes than the more comprehensive OBD-2 system, so ....KEP chose the simplest OBD-1 Subaru engine with acceptable horsepower for a Vanagon....that this engine is highly regarded as one of the most reliable Subaru has ever made....was an added incentive.

Hobert was successful in not only getting his own van CARB approved. He also went to the extra effort to obtain an "Executive Order" from the CARB which provided that a Vanagon with the 90-95 Subaru 2.2L and the KEP manufactured conversion parts would be accepted as California smog legal, provided that no more then three specific error codes are generated by the OBD-1 system ...three codes which are from missing sensors not related to the proper function of the engine and its emission control system.

Although KEP’s adapter plate, flywheel, and headers, work with almost all 4 cyl Subarus, Kennedy suggested that customers buying his parts use the OBD-1 2.2L engine and, for several years, most of us did just that...!!

Naturally, however many were curious about using other engines...me included. In fact, back in 2000 when I was asking myself, “Which engine should I use?, I wanted to put a 3.3L 230hp six cylinder Subaru in my Syncro Westy...but noone had done this conversion at that time and I was insecure about trying to pioneer this conversion, so I (wisely at the time) took his advice to “keep it simple” and used the already proven 2.2L.

Besides the KEP instruction set, I poured over the first two independent web sites that were put up that had photos and tips about the conversion process...both using the 2.2L.

I was alone and often confused while working on my conversion, so I started this Group to get help and to share what I was learning. Since then a few others have joined (2500+) and quite a few have written many details about their experiences and answer technical questions on the Group.

The popularity of the conversion has spread nationwide...even worldwide... and curious sorts that humans are...(creative too)...the ones not constrained by California smog regs starting using other Subaru engines.... and several other vendors, Smallcar Performance, H&R Motors, Scott Foss, Leon Korkin, Tom Shiels, and other professionals have enhanced the conversion by offering additional conversion parts, and services not offered by KEP. Now it is quite common to see conversions...mostly outside CA..using ALL the other great boxer engines that Subaru offers.

The later model 2.5L is probably the second most popular engine...(the SOHC version).

In the past year, the 3.3L six from the SVX has been installed in quite a few vans and is probably the third most poplular engine.

In a few rare cases,..even the turbo/intercooled 4 cyl versions from the WRX have been used. (The lesser powered 90-94 2.2L turbo, the EJ22T, is a also a strong, reliable engine but it is quite rare.)

There have even been a couple of cases of the 2.7L six from the XT-6.

So far there has been only one case using late model 3.0L, 210hp six...installed by Smallcar, but, even though its been made by Subaru since 2001, it's still very expensive to buy.
--------------------------------------------------------------------

The 2.2L is easy to find throughout the U.S. and very inexpensive to purchase,..... usually from a few hundred dollars up to $1000, but they are getting very difficult to find with low mileage. (By low I mean less than 100K miles).

But this little engine is VERY reliable engine (if given reasonable care in its first incarnation). It commonly goes 200K-300K miles. Usually the Legacy tranny or some other parts of the 90-94 Legacy go long before the engine.....providing us with buying opportunities. I would not hesitate to use one with 150K miles which has good compression and can be verified to run and idle correctly.

CCR Engine Rebuilders in Colorado, who specialize in rebuilding Subaru engines, has often endorsed the 90-94 2.2L as the most reliable engine that Subaru has ever made. The later model OBD-2, 2.2L engines, are also very good engines.

(I have used a 92 2.2L in my Syncro Westy for over four years and had no problems at all until I needed a new radiator at 164K and got an air lock in the cooling system while refilling it...overheated and "broke" it. The 2.2L was a wonderful improvement in driveability...even in this 5000+lb. van. However, my replacement will be a 2.5L from a 2002 Impreza 2.5RS.)

Naturally, it's quite a bit easier to find low mileage versions of the later model engines.

In popularity, the SOHC 2.5L is the most common OBD-2 engine used, but it usually cost twice the price of the 2.2L...or more.

(NOTE: The DOHC 2.5L used in 1996-1999 Legacy Outback and 2.5RS Impreza, has a history of frequent headgasket problems...but, nevertheless, is
popular with the sand car crowd because it can be "built" into a BIG horsepower turbo motor. It can be a reliable engine if the
headgaskets are replaced with the latest version.) However, it still costs quite a bit more to purchase than the 2.2L.

Ask yourself: “What kind of Van do I have?”, “What are the smog compliance laws in my state?”, “What kind of driving do I like to do?”

In any passenger van 2wd or Syncro, and a 2wd Westy...you would find a 2.2L an absolutely HUGE improvement...transforming the character of your van completely. Your van will feel like a modern vehicle (well almost) and you’ll be able to climb any mountain pass along with the traffic. Think about that!

If you live outside CA and have less demanding smog and engine conversion laws...your choice of engines is much greater.

You could use a 2.5L with and have only a very minor increase in the complexity of the conversion. The only drawback is the higher cost of the engine. You could also use any other Subaru engine for that matter (they're all waterboxers after all).

For the adventurous...skilled, or well endowed in the wallet, the 3.3L six or the turbo motors will provide a conversion with thrills not dreamed of for Vanagon drivers. Go for it if you qualify.

Following is an attempt to list the engine choices in order of complexity and expense.

(Obviously diligence and luck may give you a better deal...but the numbers are typical in my area.)

Also please NOTE: The cost of the conversion parts are similar for most of the 4 cyl engines, slightly to significantly more for the 3.3L...depending on whose headers you buy.
----------------------------------------------

90-94 OBD-1, 2.2L – simplest conversion, least expensive. ($300-$900)

95-99 OBD-2, 2.2L - slightly more complex and expensive ($500-$1200)

1995-1999 OBD-2 2.5L DOHC, not often used, but can be a good engine if rebuilt with latest head gaskets. Prices start around ($1200- $1700)

1999-200_ OBD-2, 2.5L SOHC – the preferred 2.5L, probably twice the cost of a 2.2L ($1200-$2200)

1992-1995 OBD-1, 3.3L DOHC 6 cyl - Whoopee!! 230hp...It’s heavy...it’s a tight fit in the Vanagon engine bay, ....but loved by those that have them...($1000-$1500) Note:*** 1996-1997 models are OBD-2.

Turbos: 2.2L and 2.0L Turbo - complex to install..for the creative and qualified few.....but big-time FUN factor... see <www.vwrx.com>
(around $1000 for the 2.2L turbo if you can find one). ($1500-$2500 for the WRX 2.0L models).

2001-200_ , 3.0L six...VERY expensive, only one in a Vanagon so far...it took three shops on two coasts to solve cooling problems...(owned by popular rock star with deep pockets) ($3000-$4500) for the engine.
--------------------------------------------------------

JP

Tue Apr 08, 2008 2:39 pm

Quote: Here are some other things they have told me that I have to question:

1. Normally Vanagons will need to have their head gaskets replaced once every year or every other year. (Sounds like they are reusing a lot of heads that have been machined into oblivion and thus failing).

What a load.

Installed with care, the wbx motor does NOT need periodic water jacket seal replacements, for the life of the motor. It is not "the nature of the beast". The design works, but the bad reputation this motor got saddled with was primarily due to the wrong coolant being used from the factory, followed by lack of periodic cooling system maintenance. It didn't help that VW chose a coolant incompatible with an all-aluminum motor and then told owners it was a lifetime coolant, which guaranteed that it would stay in the motor long enough to do harm.

Notice I said "installed with care", rather than "done properly". The latter would mean "by the book", but the book procedure is deficient in one regard: it doesn't allow for the very realistic possibility of leakage around the back of the channel seal. If there is any pitting, nicks, or other physical damage on the endface of the water jackets, the channel seal will leak around the back side. Ask me how I know.

The remedy is simply to use sealant on both sides of the gasket. That takes care of that problem, and service life of the repair is indefinite provided several other things are checked and replaced during the course of the job.

The head sealing surface must smooth and unpitted. Installing new heads guarantees that that will be true, although there are many cases of pitted heads being reused successfully after welding/remilling, or patching with epoxy and face-sanding. But the heads, if high-mileage, need to be carefully checked for other lurking problems before going to such lengths.

We read here of many cases where the head reseal is done, but the heads are foolishly assumed to be good. Anyone with experience on these motors will know that if the heads have been in service more than 100k miles, and especially if the motor has ever overheated (due to chronic loss of coolant from leaking water jacket seals, perhaps?) there are decent odds that the heads have unseen cracks. They either need to be pressure-tested on the bench or replaced to guarantee that the job is done completely and the motor will not experience more cooling system problems after the repair.

Also, any cooling system work that does not include a new thermostat and pressure cap is asking for more trouble. These two cheap, failure-prone, but nonetheless critical items have been part of routine cooling system maintenance on water cooled motors since there was such a thing.

Finally, we all know that this motor, like many aluminum motors, wants to have only phosphate-free, low-silicate antifreeze, mixed 50/50 with non-hard water (distilled if your water sources have dissolved minerals), and that the coolant should be renewed periodically, like every 3 or 4 years. I have gone twice that long and nearly 100k miles on a single batch of phosphate-free coolant, and found no pitting whatsoever on the heads at teardown, so head corrosion and subsequent failure of the jacket seals is by no means "the nature of the beast".

You need a new mechanic.

Tue Apr 08, 2008 2:46 pm

Gauche1968 wrote:

Here are some other things they have told me that I have to question:

1. Normally Vanagons will need to have their head gaskets replaced once every year or every other year. (Sounds like they are reusing a lot of heads that have been machined into oblivion and thus failing).

2. If you convert to a Subaru you are right back to an engine with head gasket problems. Is this true?

#1: This is the most ridiculous lie I've ever heard. If it's coming from a mechanic he's either: 1, Never worked on a vanagon before and dumb enough to make a comment based on no experience, or 2, someone who knows but is intentionally giving you bad info.

#2: Pretty much the same as #1. Either way it doesn't look good.

Tue Apr 08, 2008 2:49 pm

I figured that was the case tencent. I grew suspicious of this operation immediately after the first repair failed, but I am kind of stuck with them trying to remedy this problem. Of course, now I am at the point where i cannot justify spending anymore money on this with them, because they clearly do not know what they are doing.

Tue Apr 08, 2008 3:17 pm

I did not catch on #1.

Surprisely, I was once told by a specialist and reputed vanagon mech that head gasket were considered "regular maintenance" in a sense that "needed to be changed once in a while".

All that said, it will come up more often than you need/want but no every year/other year. It can happen, but that's bad luck or more likely: bad installation.

I still find it too pricey and unreliable but...

JP

Tue Apr 08, 2008 3:31 pm

tencentlife wrote: Quote: Here are some other things they have told me that I have to question:

1. Normally Vanagons will need to have their head gaskets replaced once every year or every other year. (Sounds like they are reusing a lot of heads that have been machined into oblivion and thus failing).

What a load.

Installed with care, the wbx motor does NOT need periodic water jacket seal replacements, for the life of the motor. It is not "the nature of the beast". The design works, but the bad reputation this motor got saddled with was primarily due to the wrong coolant being used from the factory, followed by lack of periodic cooling system maintenance. It didn't help that VW chose a coolant incompatible with an all-aluminum motor and then told owners it was a lifetime coolant, which guaranteed that it would stay in the motor long enough to do harm.

Notice I said "installed with care", rather than "done properly". The latter would mean "by the book", but the book procedure is deficient in one regard: it doesn't allow for the very realistic possibility of leakage around the back of the channel seal. If there is any pitting, nicks, or other physical damage on the endface of the water jackets, the channel seal will leak around the back side. Ask me how I know.

The remedy is simply to use sealant on both sides of the gasket. That takes care of that problem, and service life of the repair is indefinite provided several other things are checked and replaced during the course of the job.

The head sealing surface must smooth and unpitted. Installing new heads guarantees that that will be true, although there are many cases of pitted heads being reused successfully after welding/remilling, or patching with epoxy and face-sanding. But the heads, if high-mileage, need to be carefully checked for other lurking problems before going to such lengths.

We read here of many cases where the head reseal is done, but the heads are foolishly assumed to be good. Anyone with experience on these motors will know that if the heads have been in service more than 100k miles, and especially if the motor has ever overheated (due to chronic loss of coolant from leaking water jacket seals, perhaps?) there are decent odds that the heads have unseen cracks. They either need to be pressure-tested on the bench or replaced to guarantee that the job is done completely and the motor will not experience more cooling system problems after the repair.

Also, any cooling system work that does not include a new thermostat and pressure cap is asking for more trouble. These two cheap, failure-prone, but nonetheless critical items have been part of routine cooling system maintenance on water cooled motors since there was such a thing.

Finally, we all know that this motor, like many aluminum motors, wants to have only phosphate-free, low-silicate antifreeze, mixed 50/50 with non-hard water (distilled if your water sources have dissolved minerals), and that the coolant should be renewed periodically, like every 3 or 4 years. I have gone twice that long and nearly 100k miles on a single batch of phosphate-free coolant, and found no pitting whatsoever on the heads at teardown, so head corrosion and subsequent failure of the jacket seals is by no means "the nature of the beast".

You need a new mechanic.

=D> =D>

Tue Apr 08, 2008 7:53 pm

I appreciate everyone's insight, but that still leaves me wondering what exactly is happening to this engine? I know its impossible to diagnose over the internet, but does it make any sense that a cooling system that is "over pressurizing" itself would cause a brand new gasket to blow? Would something like the radiator fan not coming on after parking cause the gasket to blow? Does it make sense that the mechanic would have to take the head off again to diagnose what is causing this?

Tue Apr 08, 2008 9:10 pm

If the cooling system is over pressurized, the overflow tank should be filling up. Because the valve in the expansion tank cap is set to open beyond a fixed psi (14 I think). If the cooling system is over pressurized, the head gasket is already bad which is what is causing the pressure. Valve opens, pushes into overflow, relieves pressure temporarily, then repeats, unitl overflow tank at maximum. Which then may cause weak old hoses to blow. Just went through that. But got if fixed.

Everything else in above posts excellent information and better than what I can add. Other than agreeing about mechanic not using enough care in the process, then making stuff up to save hours of free labor owed you.

Tue Apr 08, 2008 9:29 pm

Let me give a suggestion prior to pulling all of your hair out on this seemingly never ending head water jacket seal problem.

I've run into this very same problem once on a customer's Van, and it was expesperating to say the least.

I am a proponent of useing GM's engine assembly sealant which is without a doubt a much better & bullet proof product for the head seals.

The engine dripped very little, but it shouldn't have lost anything.

I had the heads on this engine welded & milled to get all of the pits outa the sealing surface --I don't use JB weld at all on the head sealing area.

After redoing the job again , on me---I was laying on my creeper looking up at the engine and a thought came to me---
"What if the radiator is half assed plugged up and building undo pressure's in the cooling system?"
" The water pump will be heave hoeing to the radiator, but the return will be real slow, building big pressure in the cooling system and possibly smoking the head seal's"

I got done with the heads, started the Van and did some infared temp testing at the radiator.

Damn--

Half the radiator core was stone cold--no coolant flow.

And here was the culprit---

I installed a new radiator and the head sealing problem was a thing of the past.

The engine in the Van not only ran much cooler, the slight dripping leak at the heads was all done with.

If you have no records of the cooling system's service intervals, and the Van is plenty old--I'll bet you radiator is half plugged up & causing the problem's your having with big pressure to the radiator--and no return to the engine.

I'd check the radiator core out first before tossing any stone's at the mechanic.

It's an easily overlooked, & common problem area in a 20 some year old vehicle.

Once you get everything ironed out, you can plan on not having to deal with the head seals for another 100,000 miles--plus.
( If you get on a semi annual coolant change program )

A Subaru transplant won't ever cure an old, half, or fully blocked radiator.

It'll fail too.

Good Luck,

Tue Apr 08, 2008 9:43 pm

H-four is on the right track with his observations, but with a working pressure cap, system pressure should never exceed 1 bar, about 14psi. That's why I stress the pressure cap so much, as it plays such a critical role in protecting the system overall from pressure spikes that can blow out hoses, etc. The overflow tank is vented at the top, so if the cap keeps releasing pressure, it will overfill and coolant will just spew out the top.

The only instance I can imagine where system pressure could exceed 1 bar with a working pressure cap would be if there were a bad compression seal or cracked head that allowed combustion pressure to be released into the cooling system at a rate greater than can escape out the pressure cap orifice. But that would be some leak!

The Vanagon pressure cap. although it looks different, works the same as every radiator cap ever used on a production water-cooled engine. Something needs to both contain pressure, which raises the boiling point of the coolant considerably, but also release pressure above a set level to protect the overall system from damage.

Also, like other caps since the 70's, it also contains a second valve that allows coolant to flow from the overflow tank back into the system as the fluid cools and contracts. This works independently of the pressure control function.

So the cap both contains and controls maximum system pressure, while regulating the total volume of coolant in the system. That's a lot of function for only eight bucks!

I doubt that the new leak is caused by overpressure, because a hose would be much more likely to rupture before coolant would be forced out the water jacket seal, especially a new one freshly sealed up. But if he did major cooling system work without replacing the pressure cap, all bets are off. Your mechanic sounds like he's talkin' to the wrong end of the horse, again.

Tue Apr 08, 2008 10:02 pm

For as many times as this particular engine has been repaired, for the very same thing, and with the same end result, I'd be looking for the unobvious, as I did.
To check out the radiator for coalant flow charactoristics is a simple thing, and most certainly would be much faster to run down in a process of elimination.

At this point, I'd be most certainly at least checking it out.

Tue Apr 08, 2008 10:26 pm

Just a couple of more observations:

The van has never overheated since I have owned it. Took it on a 600 mile trip just before the latest meltdown and the needle stayed flat in the middle of the LED the entire time.

When I first picked the van up after the head replacement, the overflow tank was bone empty. I filled it up to the max line and over the course of the next few weeks it did drain back down to the min line, but seemed to stabilize there. After the latest meltdown, the overflow tank is bone empty again, but the expansion tank is still full.

I had the mechanic use the VW blue coolant but the coolant leaking out of the blown gasket is completely green, looks as if it never mixed with the blue coolant at all. The expansion tank is completely full of blue coolant.