Blown Head Gasket Repair at 600 Miles

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72Hardtop
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Re: Blown Head Gasket Repair at 600 Miles

Post by 72Hardtop » Sat Sep 13, 2014 10:44 am

That would suggest then there was no need for their removal.
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
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Re: Blown Head Gasket Repair at 600 Miles

Post by asiab3 » Sat Sep 13, 2014 11:37 am

72Hardtop wrote:
asiab3 wrote: What exactly do you define as "overheating"? I've been mulling over this quite a bit- VW does not publish data in their service manuals nor the "guesswork" series. Is there a point at which we can say yes or no to "is this engine overheating?"

Or would you change your wording to "running in the hottest conditions aided in it happening sooner?"
No rewording...my belief has always been that's it's critical to keep the engine in a high state of tune as much as possible. One that isn't will be working much harder combined with running hotter. One big reason VW did not put CHT gauges in these vehicles was they knew it would freak people out given the majority of people were used to seeing a gauge on a water cooled car showing far less temps.

Keep in mind Colins experience is unlike any or most average bus owner/s (past & present) much like his attention to detail such as painting backing plates while boon docking somewhere lonely.
Ok, so what do you define as "overheating"?
1969 bus, "Buddy."
142k miles with me.
319k miles on Earth.

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Amskeptic
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Re: Blown Head Gasket Repair at 600 Miles

Post by Amskeptic » Sun Sep 14, 2014 6:33 am

72Hardtop wrote:One big reason VW did not put CHT gauges in these vehicles was they knew it would freak people out given the majority of people were used to seeing a gauge on a water cooled car showing far less temps.
NAAAAaaaaah . . . :flower: They were CHEAP. They could have put in a gauge with no numbers, just pretty colors, blue and red for example. Based on the legendary reliability of air-cooled VW engines up through the 60's, they felt no need to monitor such an under-stressed engine. Now, at what point do they begin to wonder if they should? Late 60's? Early 70's? They just gritted their teeth and demanded that we follow the directions as far as state of tune. The factory always always advised against performance modifications to their engines, because they did their homework and knew that things would make it to the 100,000 mile mark OK.
72Hardtop wrote: Keep in mind Colins experience is unlike any or most average bus owner/s (past & present) much like his attention to detail such as painting backing plates while boon docking somewhere lonely.
NAAAAAaaah, I might shine stuff and stuff, but look far and wide for anything special in the engine compartment . . . y'ain't gonna find it. I tune according to the directions and drive! You might have found a few intense moments where I had to find out an over-flycut head in the Road Warrior, or who made what mistake in Chloe (too-small exhaust valves anyone?) for example, but once everything is set up correctly, I just drive the snot out of them.
Colin

(p.s. overheating in a VW is pretty much "already too late". You smell oil cooking on parts, you note a loss of power when the pistons smear themselves all over the cylinder walls. Back in the day, an overhaul was as easy a new piston/cylinder and an exchange head from the dealer. Now we have "gauges" and arguments galore about what number is the "overheat number")
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

72Hardtop
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Re: Blown Head Gasket Repair at 600 Miles

Post by 72Hardtop » Sun Sep 14, 2014 10:57 am

Amskeptic wrote:
72Hardtop wrote:One big reason VW did not put CHT gauges in these vehicles was they knew it would freak people out given the majority of people were used to seeing a gauge on a water cooled car showing far less temps.
NAAAAaaaaah . . . :flower: They were CHEAP. They could have put in a gauge with no numbers, just pretty colors, blue and red for example. Based on the legendary reliability of air-cooled VW engines up through the 60's, they felt no need to monitor such an under-stressed engine. Now, at what point do they begin to wonder if they should? Late 60's? Early 70's? They just gritted their teeth and demanded that we follow the directions as far as state of tune. The factory always always advised against performance modifications to their engines, because they did their homework and knew that things would make it to the 100,000 mile mark OK.
72Hardtop wrote: Keep in mind Colins experience is unlike any or most average bus owner/s (past & present) much like his attention to detail such as painting backing plates while boon docking somewhere lonely.
NAAAAAaaah, I might shine stuff and stuff, but look far and wide for anything special in the engine compartment . . . y'ain't gonna find it. I tune according to the directions and drive! You might have found a few intense moments where I had to find out an over-flycut head in the Road Warrior, or who made what mistake in Chloe (too-small exhaust valves anyone?) for example, but once everything is set up correctly, I just drive the snot out of them.
Colin

(p.s. overheating in a VW is pretty much "already too late". You smell oil cooking on parts, you note a loss of power when the pistons smear themselves all over the cylinder walls. Back in the day, an overhaul was as easy a new piston/cylinder and an exchange head from the dealer. Now we have "gauges" and arguments galore about what number is the "overheat number")
I agree with Colin on this with regards to a 'specific overheat temp'. VW never offered one up or alluded to a specific number. One thing is certain If the engine begins to smoke and cook oil...you've reached the over heat state. At that point it's generally too late.

Given we see 400 degree numbers from owners of buses quite often I'd say that 400 isn't considered overheating. As for the jump from 60's to 70's+...VW knew it was time to make a switch from the T-1 when the smog requirements began. The T-1 in a bus was already asking for a lot of work to be had from the engine. A typical T-1 powered bus won't make it to 100,00 miles without a full rebuild. VW however knew the T-4 was a different breed engine. Therefore I believe that is why they deemed the no need of CHT gauge.

Roll forward to today and more knowledge from experience has been gained to what can and cannot be done with the T-4 effectively without sacrificing it's legendary reliability. I remember as a kid growing up and learning from both Dennis & Lloyd about the T-4 engine and they meticulously taught me to never cut corners when rebuilding and always use German parts (unless proven otherwise). It was a lot of fun watching what those guys did on a daily basis in the shop. They made it seem so easy.

These days it's getting very difficult to find new quality parts for the T-4. You generally end up with NOS or some old half worn out item. Or a part that lasts only a few days to a few weeks. This was part of the reason why my friend Dennis retired as he saw the end coming starting right around 2000.

The T-4 heads have long been considered the weak link in the T-4 overall. But with T-4 head builders such as Adrian and Len Hoffman the weak links have been made much stronger due to gains made thru past experience/s and improvements in head material/s as well as workmanship of the cylinder head itself.
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

CarlosZ
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Re: Blown Head Gasket Repair at 600 Miles

Post by CarlosZ » Thu Feb 02, 2017 10:08 am

So what's the consensus on the head gaskets? Yeah or Nay? Reason I as is that I've read conflicting info regarding the topic. I'm having an engine built and told the builder over and over NOT to use the head gaskets as per the VW tech bulletin. Yesterday he tells me that he's almost done and used them. He says they're not used on AMC heads and confuses me with technical jargon. I have a 2.0 GD case, VW 2.0 heads and a Web73 cam. So pissed, should've built it myself as others suggested. He's closed today and looking for some good ammo if I decide to have him take it all apart tomorrow. Also, I don't really care if they can be used w/o issue. I just want to have it built properly. Thanks and flame away.

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Re: Blown Head Gasket Repair at 600 Miles

Post by 72Hardtop » Thu Feb 02, 2017 3:45 pm

CarlosZ wrote:So what's the consensus on the head gaskets? Yeah or Nay? Reason I as is that I've read conflicting info regarding the topic. I'm having an engine built and told the builder over and over NOT to use the head gaskets as per the VW tech bulletin. Yesterday he tells me that he's almost done and used them. He says they're not used on AMC heads and confuses me with technical jargon. I have a 2.0 GD case, VW 2.0 heads and a Web73 cam. So pissed, should've built it myself as others suggested. He's closed today and looking for some good ammo if I decide to have him take it all apart tomorrow. Also, I don't really care if they can be used w/o issue. I just want to have it built properly. Thanks and flame away.
Per the VW tech bulletin....He's not to use them. It also includes notching the connecting rods. If you're using AMC heads they already have a step machined into the head itself. No need for the gasket.
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

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Re: Blown Head Gasket Repair at 600 Miles

Post by cegammel » Thu Feb 02, 2017 4:49 pm

But, deleting the gasket changes the compression ratio...
They can used without issue, but they will blow again. Did the shop notch the rods, or just new gaskets?

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Amskeptic
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Re: Blown Head Gasket Repair at 600 Miles

Post by Amskeptic » Sat Feb 11, 2017 6:48 am

cegammel wrote:They can used without issue, but they will blow again. Did the shop notch the rods, or just new gaskets?
The sealing rings are NOT a weak link, and they can be used as necessary. I have never lost a sealing ring in my life.
If you have blown a sealing ring, it is because of a precipitating event, like overheating.

The deletion of the sealing ring was to speed up heat transfer to the cylinder barrels under heavy load and high heat conditions where there was a known risk of scuffing (smearing 94mm piston skirts all over the cylinder walls)!

If the rods are notched, that'll help.
If the piston/cylinder clearances are + .002" you will likely be fine.
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

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Re: Blown Head Gasket Repair at 600 Miles

Post by Amskeptic » Sat Feb 11, 2017 6:52 am

CarlosZ wrote:So what's the consensus on the head gaskets? Yeah or Nay? Reason I as is that I've read conflicting info regarding the topic. I'm having an engine built and told the builder over and over NOT to use the head gaskets as per the VW tech bulletin. Yesterday he tells me that he's almost done and used them. He says they're not used on AMC heads and confuses me with technical jargon. I have a 2.0 GD case, VW 2.0 heads and a Web73 cam. So pissed, should've built it myself as others suggested. He's closed today and looking for some good ammo if I decide to have him take it all apart tomorrow. Also, I don't really care if they can be used w/o issue. I just want to have it built properly. Thanks and flame away.
Ask about the rod notching and the increased piston/cylinder clearance demanded by the technical service bulletin.

Please note that the sealing rings were not prone to failing . . . they failed due to other causes. They were deleted in the TSB strictly to increase immediate heat transfer from the combustion chambers to the cylinder barrels under load to help prevent piston scuffing!
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

72Hardtop
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Re: Blown Head Gasket Repair at 600 Miles

Post by 72Hardtop » Thu Apr 27, 2017 8:43 pm

Amskeptic wrote:
Sat Feb 11, 2017 6:52 am
CarlosZ wrote:So what's the consensus on the head gaskets? Yeah or Nay? Reason I as is that I've read conflicting info regarding the topic. I'm having an engine built and told the builder over and over NOT to use the head gaskets as per the VW tech bulletin. Yesterday he tells me that he's almost done and used them. He says they're not used on AMC heads and confuses me with technical jargon. I have a 2.0 GD case, VW 2.0 heads and a Web73 cam. So pissed, should've built it myself as others suggested. He's closed today and looking for some good ammo if I decide to have him take it all apart tomorrow. Also, I don't really care if they can be used w/o issue. I just want to have it built properly. Thanks and flame away.
Ask about the rod notching and the increased piston/cylinder clearance demanded by the technical service bulletin.

Please note that the sealing rings were not prone to failing . . . they failed due to other causes. They were deleted in the TSB strictly to increase immediate heat transfer from the combustion chambers to the cylinder barrels under load to help prevent piston scuffing!
Piston scuffing was directly related to piston-cylinder clearance not sealing ring. The fix was for piston scuffing per VW tech bulletin was as follows:

1. To eliminate seizing of pistons, increased piston/cylinder clearance from 0.03mm ± 0.008mm to 0.045mm ± 0.005mm

2. Eliminate aluminum seal 021 101 341A between cylinder and cylinder head.

3. Eliminate paper gasket 021 101 341A between foot of cylinder and crankcase.

4. Install 1.6mm aluminum shim 071 101 341, with adhesive D 000 400 at foot of cylinder to compensate for removed paper gasket and aluminum seal. Illustration 1.

5. To improve heat transfer, oil groves on both sides of the connecting rod to allow oil splash to cool bottom of the piston.

They were looked at as separate issues that needed to be resolved. Following the bulletin and leaving the sealing rings in place minus the shim was to costly a price for VW to pay. End result: Ditch the sealing rings and add base shim.

The removal of the head rings was directly related to their failure overtime. The thinness of them overtime in the combustion area (high pressure) would erode them overtime. If one overheated the bus (which was quite common) that would allow for the sealing rings to erode/burn through even faster.

The sealing rings do not increase heat transfer given they are same metal material as the head. The repeated heat cycling (movement & heat) of the engine would erode the sealing rings overtime and VW knew that removing them and adding shim at base then lapping the heads was a much better alternative. Now with the AMC heads one has the added step that in essence takes the sealing rings place and allows for a better seal when lapping the cylinders into the heads.
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

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asiab3
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Re: Blown Head Gasket Repair at 600 Miles

Post by asiab3 » Thu Apr 27, 2017 9:22 pm

72Hardtop wrote:
Thu Apr 27, 2017 8:43 pm
Amskeptic wrote:
Sat Feb 11, 2017 6:52 am
CarlosZ wrote:So what's the consensus on the head gaskets? Yeah or Nay? Reason I as is that I've read conflicting info regarding the topic. I'm having an engine built and told the builder over and over NOT to use the head gaskets as per the VW tech bulletin. Yesterday he tells me that he's almost done and used them. He says they're not used on AMC heads and confuses me with technical jargon. I have a 2.0 GD case, VW 2.0 heads and a Web73 cam. So pissed, should've built it myself as others suggested. He's closed today and looking for some good ammo if I decide to have him take it all apart tomorrow. Also, I don't really care if they can be used w/o issue. I just want to have it built properly. Thanks and flame away.
Ask about the rod notching and the increased piston/cylinder clearance demanded by the technical service bulletin.

Please note that the sealing rings were not prone to failing . . . the failed due to other causes. They were deleted in the TSB strictly to increase immediate heat transfer from the combustion chambers to the cylinder barrels under load to help prevent piston scuffing!
Piston scuffing was directly related to piston-cylinder clearance not sealing ring. The fix was for piston scuffing per VW tech bulletin was as follows:
But piston/cylinder clearance changes throughout the warmup cycle! The pistons receive the bulk of combustion heat FIRST, and expand sooner and quicker. Yes, the increased clearance would help, but removing the compression gasket does increase heat transfer into the cylinder walll aiding in its thermal expansion as well. VW released this bulletin as a system. It wasn't "delete the rings." It was "delete the rings, increase the clearance, space the CR back, and notch the rods." We all know that ACVW's require complete systems to be maintained, not just one step to fix one issue.

The removal of the head rings was directly related to their failure overtime. The thinness of them overtime in the combustion area (high pressure) would erode them overtime. If one overheated the bus (which was quite common) that would allow for the sealing rings to erode/burn through even faster.
The TSB we're speaking of was released in May of 1990. You say that the sealing rings leaking were why VW released the tech bulletin? My speculation is that many original 2.0 Type 4 engines were just starting to hit the end of their reliable life span by then, and VW was tearing them down to remanufacture. And they found piston scuffing, so they remedied that. Nobody would bring their bus in for "I think there is piston on my cylinder wall." But don't you think VW would have seen a much larger dealership work order trend if all the sealing rings were failing like you proffer? Failed rings cause low compression, leaky noises, low power, and all that jazz. Any one of those symptoms would cause a customer to bring their car in. It seems VW was clear in the TSB to say "to eliminate seizing of pistons" but never mention "to eliminate leaking of combustion chambers" or the like.
The sealing rings do not increase heat transfer given they are metal material. The repeated cycling (movement & heat) of the engine would erode the sealing rings overtime and VW knew that removing them and lapping the heads was a much better alternative. Now with the AMC heads one has the added step that in essence takes the sealing rings place and allows for a better seal when lapping the cylinders into the heads.
Sealing rings absolutely reduce heat transfer, just like the metal spacer that VW introduced under the TS2 to extend warm up times. This time, VW removed the spacer to speed up heat transfer, which helps increase piston-to-cylinder clearance during warm up.

Perhaps lapping is a better alternative, it seems to be more successful when the average Joe is assembling an engine in their dirty garage. But VW was not that. And without data from mass VW engine teardown, we can only speculate using skewed data from "help my Volkswagen is broken" websites.

Carlos, if your engine required sealing rings, it required sealing rings. If it didn't, then you could have left them out. New AMC heads have the built-in step that, if used WITH sealing rings, might cause an excessively low compression ratio. What was your compression ratio in the end?

(Carlos' engine was finished a few weeks ago, but I'd like to know for posterity.)
Robbie
1969 bus, "Buddy."
142k miles with me.
319k miles on Earth.

72Hardtop
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Re: Blown Head Gasket Repair at 600 Miles

Post by 72Hardtop » Fri Apr 28, 2017 12:40 am

The info that was provided me was from two very reliable sources (former VW techs) who went independent during VWs hay days. There were a lot more independent shops doing work then than now. They were getting a size able amount of work compared to dealers given most warranties were long up.

What they were finding out was being dealt over to VW who was also seeing the same. The tech bulletin was as follows:



Tech bulletin:

Engines, P/N 071 100 031AX, 039 100 031 B/C/DX, have been modified to improve heat transfer an increase durability. These changes effect Engine codes: GD, GE, CV.

The following improvements have been introduced as of remanufactured Engine number 89000.



To eliminate seizing of pistons, increased piston/cylinder clearance from 0.03mm ± 0.008mm to 0.045mm ± 0.005mm.


Eliminate aluminum seal 021 101 341A between cylinder and cylinder head.


Eliminate paper gasket 021 101 341A between foot of cylinder and crankcase.


Install 1.6mm aluminum shim 071 101 341, with adhesive D 000 400 at foot of cylinder to compensate for removed paper gasket and aluminum seal. Illustration 1.



To improve heat transfer, oil groves on both sides of the connecting rod to allow oil splash to cool bottom of the piston. Illustration

-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

The heat transfer now directly transferred without passing thru a weak link. While the engine is on one has heat and a lot of motion (not visible to the eye) that motion would work away at that sealing ring . It would find its weakest spot and the end result was loss of power, head leak issue that would result in one going to the shop.

If one was overheating the bus (quite common) the end result just happened quicker. Bottom line is at no time after the bulletin did VW ever suggest or offer their (head gaskets) continued use. They were removed per tech bulletin.

The bulletin starts by stating to 'improve heat transfer and increase durability' VW easily came to the decision that the sealing rings were just not needed and they decreased overall durability and only ended up being a 'Canary in the coal mine' if left alone and not removed.

The tech bulletin does not make mention of lowering the CR.

Anyone who had an issue with them being removed per the bulletin were turned away given no shop (VW Dealer) would do the work.

If Carlos engine required the sealing ring it was due to the heads being over cut. The correct fix is get heads that aren't over cut. No VW shop dealer or otherwise would go the route of installing over cut heads with sealing rings. VW never suggested their use at anytime after tech bulletin was released. Nor would they install over cut heads.
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

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Re: Blown Head Gasket Repair at 600 Miles

Post by Amskeptic » Sat Apr 29, 2017 6:52 pm

"No VW shop dealer or otherwise would go the route of installing over cut heads with sealing rings."

They absolutely would and they absolutely do. Look at Air-Cooled.Net's selection of copper head sealing rings. Look at your factory engine manuals.

Sealing rings were installed in millions! of Type 4 engines from 1970! onwards. They were not a known failure point. They were only canaries in coal mines for those engines that endured traumatic overheats (many of which arose from dealer mechanics). The TSB was for only the 2.0 engine with the 94mm cylinders that had this bumper crop of scuffed pistons that then sounded like little diesel engines once the skirts were collapsed.

"Improved heat transfer", said the bulletin. Damn right. We are talking of course, of momentary heat spikes on hills and headwinds that caused a momentary "unsynchronization" of heat expansion rates between the piston and the cylinder wall. That is all.

The thread that just won't die.
Colin

p.s.
"Anyone who had an issue with them being removed per the bulletin were turned away given no shop would do the work."

What? )
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

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Amskeptic
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Re: Blown Head Gasket Repair at 600 Miles

Post by Amskeptic » Sat Apr 29, 2017 7:00 pm

72Hardtop wrote:
Thu Apr 27, 2017 8:43 pm
Amskeptic wrote:
Sat Feb 11, 2017 6:52 am

They were deleted in the TSB strictly to increase immediate heat transfer from the combustion chambers to the cylinder barrels under load to help prevent piston scuffing!

The sealing rings do not increase heat transfer (given they are metal material).


That is exactly what I said. The ABSENCE of sealing rings DID INCREASE heat transfer from the heads to the barrels to help keep their expansion ahead of the pistons' expansion.
AGAIN -
This was a THREE-PRONGED ATTACK against the same problem.
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

72Hardtop
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Re: Blown Head Gasket Repair at 600 Miles

Post by 72Hardtop » Sat Apr 29, 2017 9:19 pm

Amskeptic wrote:
Sat Apr 29, 2017 6:52 pm
"No VW shop dealer or otherwise would go the route of installing over cut heads with sealing rings."

They absolutely would and they absolutely do. Look at Air-Cooled.Net's selection of copper head sealing rings. Look at your factory engine manuals.

Sealing rings were installed in millions! of Type 4 engines from 1970! onwards. They were not a known failure point. They were only canaries in coal mines for those engines that endured traumatic overheats (many of which arose from dealer mechanics). The TSB was for only the 2.0 engine with the 94mm cylinders that had this bumper crop of scuffed pistons that then sounded like little diesel engines once the skirts were collapsed.

"Improved heat transfer", said the bulletin. Damn right. We are talking of course, of momentary heat spikes on hills and headwinds that caused a momentary "unsynchronization" of heat expansion rates between the piston and the cylinder wall. That is all.

The thread that just won't die.
Colin

p.s.
"Anyone who had an issue with them being removed per the bulletin were turned away given no shop would do the work."


What? )
I was specifically referring to dealer said work. No dealer would install over flycut heads in the face of the TSB in their hand. Never would happen. Independent shops it was up to the owner. The ones I knew would not as well (liability). The fix was later adapted to 1.7 and 1.8 engines as well.

The sealing rings are aluminum. The heads are aluminum. Same material. Removing them (sealing rings) does not speed up and/or alter transfer. It only eliminates an issue that was already manifesting itself from owners having brought their vehicles in overtime when VW started to take notice of the issue. The improvement of heat transfer was provided via 'oil grooves' on both sides of the connecting rods (per VW tech bulletin) allowing oil to splash bottom of piston.
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

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