Vanagon issues...low compression...

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Amskeptic
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Re: Vanagon issues...low compression...

Post by Amskeptic » Thu Aug 16, 2018 4:52 am

TrollFromDownBelow wrote:
Tue Aug 14, 2018 7:26 pm

those exhaust studs need every bit of thread of thread inside the head that they can grab.
^ this ^
Colin :flower:
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

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Re: Vanagon issues...low compression...

Post by cegammel » Thu Aug 16, 2018 4:49 pm

We are back up and running! I do now have a chirp when I first ease off the clutch...so maybe doing that job sooner than expected. I have a few more things to do and redo, but I hope all is safe and sound back there.

I had serious airbound noise before a 20 minute run. Sitting out of oil for two weeks...I know that's not how it is supposed to work...

My head temps are disconcerting.
VDO reads just under 300. Hand held reads 288 through the #3 spark boot tin hole. But, underneath, the handheld shows 388 on the bottom of the 1/2 head and about 360 on the 3/4.

Len doesn't want his heads going over 410, I think.

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Re: Vanagon issues...low compression...

Post by cegammel » Fri Aug 17, 2018 6:33 pm

Found my chirp...I forgot the muffler strap, so it was rubbing on my crossover on take off and shifts...

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Re: Vanagon issues...low compression...

Post by SlowLane » Sun Aug 19, 2018 10:39 am

cegammel wrote:
Fri Aug 17, 2018 6:33 pm
Found my chirp...I forgot the muffler strap, so it was rubbing on my crossover on take off and shifts...
Gotta love the easy fixes...
cegammel wrote: Len doesn't want his heads going over 410, I think.
I'm disappointed to hear that Len has any restrictions on the CHT for his heads. I had assumed that he and Jake had figured out what was necessary to immunize T4 heads against the dreaded valve seat drop. For me, that would have been the primary driver for getting a pair from him: the prospect of being able to just drive without fretting over the CHT getting up into the "danger zone" above 400 F.

But if Len is cautioning his customers to not go over 410 F, then that doesn't really buy us much. My CHTs will shoot over 410 easily while climbing a hill if I don't watch it.
'81 Canadian Westfalia (2.0L, manual), now Californiated

"They say a little knowledge is a dangerous thing, but it is not one half so bad as a lot of ignorance."
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Re: Vanagon issues...low compression...

Post by cegammel » Sun Aug 19, 2018 3:28 pm

For me, that would have been the primary driver for getting a pair from him
Call him before making a decision...I don't remember stuff well. I do know that with the ceramic coatings the heads should shed heat better, and so a short hot run should be less damaging. I have only seen head temps near 400 once, and that was pilot error. Even at 65, I only hit about 350-370 on flat South GA highways.

But yeah, I was also expecting much higher allowances...

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Re: Vanagon issues...low compression...

Post by cegammel » Sun Aug 19, 2018 3:31 pm

In other news...

With the generosity of the IAC community, I put together a useable set of valve screws, bit went ahead and ordered a set from German Supply. Something happened in payment, and my $148 got sent to someone other than them from their website. "The problem should be resolved in 24 hours" was 6 days ago. $148 for 8 screws...and I can't even get it done right at that price. I am disappointed...

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Re: Vanagon issues...low compression...

Post by cegammel » Sun Aug 19, 2018 3:36 pm

From Len:

"Please keep in mind that despite the high quality parts and castings your heads are susceptible to heat damage. Sustained CHT’s in excess of 350* will shorten the life span, and even more damaging are sustained EGT’s of 1200* or higher. The most significant heat related damage occurs at full throttle. The longer the full throttle duration, the more critical proper temp control becomes. Do not run with temps in excess of 410* Please be advised that heat related damage is not covered by our limited warranty."

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Re: Vanagon issues...low compression...

Post by Amskeptic » Mon Aug 20, 2018 6:30 am

cegammel wrote:
Sun Aug 19, 2018 3:36 pm
From Len:

"Please keep in mind that despite the high quality parts and castings your heads are susceptible to heat damage. Sustained CHT’s in excess of 350* will shorten the life span, and even more damaging are sustained EGT’s of 1200* or higher. The most significant heat related damage occurs at full throttle. The longer the full throttle duration, the more critical proper temp control becomes. Do not run with temps in excess of 410* Please be advised that heat related damage is not covered by our limited warranty."

Well that may be the case over in LenLand, but I have been running temps that do not drop below 350*. I am consistently in the 400-420* and have done long long long full-throttle blasts up interminable hills and have hit 441* this summer more than once, and drove through 430* several times. These heads are at 87,500 miles. Same for the BobD at 111,000 miles. The deciding factor for my shocking lack of concern has been stable valve adjustments and sweet-smelling rocker boxes.

MAYBE . . . . AMC heads do not have the density of the original heads.

I hope to have a conversation with Len later this itinerary.
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

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Re: Vanagon issues...low compression...

Post by cegammel » Tue Sep 04, 2018 3:23 pm

Ok, guys and gals ...I know you all are enamored with German supply, but it took a week and a half to get my money back from their website glitch, I paid again, and now I can't get a response as to my order. I have now been in hole $148 for a month with essentially no contact. These better be some nice frickin screws.

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THall
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Re: Vanagon issues...low compression...

Post by THall » Wed Sep 05, 2018 3:59 am

cegammel wrote:
Tue Sep 04, 2018 3:23 pm
Ok, guys and gals ...I know you all are enamored with German supply, but it took a week and a half to get my money back from their website glitch, I paid again, and now I can't get a response as to my order. I have now been in hole $148 for a month with essentially no contact. These better be some nice frickin screws.
Unfortunately, that's par for the course with GS these days. Over on the Samba Buyer & Seller feedback thread there are pages of unhappy customers over the past number of years....same story; no response and looooong wait times to receive parts.

https://www.thesamba.com/vw/forum/viewt ... p?t=158895
'78 Westy 2.0 FI

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Re: Vanagon issues...low compression...

Post by cegammel » Sat Oct 20, 2018 5:28 pm

Update:. Made my first speed run today with the heads and valve screws. I pushed 60-65 and that little motor stayed at 300-330* the whole time. Plenty of power and low temps. I had one nasty hiccup where I thought it was done...a nasty gassy belch when I shifted to 2nd, but the motor recovered and ran perfectly home.

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Re: Vanagon issues...low compression...

Post by SlowLane » Sun Oct 21, 2018 12:43 pm

cegammel wrote:
Sat Oct 20, 2018 5:28 pm
I pushed 60-65 and that little motor stayed at 300-330* the whole time. Plenty of power and low temps.
Congratulations on your impressive improvement. The only time I've ever seen head temps that low at those speeds was going downhill with a strong tailwind. It was a great feeling while it lasted, but then I had to turn around...

Just for comparison, I took my van out today to fetch some ATF for my other cars. Just tooling around town at 30 MPH I was seeing CHTs in the 300-330 range, even idling at a stop light. So if you're getting the same temperatures at 65 MPH, that thermal barrier coating must be some amazing stuff.
'81 Canadian Westfalia (2.0L, manual), now Californiated

"They say a little knowledge is a dangerous thing, but it is not one half so bad as a lot of ignorance."
- Terry Pratchett

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Re: Vanagon issues...low compression...

Post by Amskeptic » Mon Oct 29, 2018 6:21 pm

cegammel wrote:
Sat Oct 20, 2018 5:28 pm
Update:. Made my first speed run today with the heads and valve screws. I pushed 60-65 and that little motor stayed at 300-330* the whole time. Plenty of power and low temps. I had one nasty hiccup where I thought it was done...a nasty gassy belch when I shifted to 2nd, but the motor recovered and ran perfectly home.

Did you run the CCs/deck height/ stroke/cylinders numbers through your compression calculator? What is your current compression ratio?
And where is your CHT sender, under the plug or elsewhere?
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

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Re: Vanagon issues...low compression...

Post by cegammel » Sat Nov 03, 2018 3:59 pm

CHT sender is under the #3 plug. I think the CR is 7.3. The new heads differed by one cc from my old ones. Nothing else changed...

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