Western Pennsylvania visit

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SlowLane
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Re: Western Pennsylvania visit

Post by SlowLane » Mon Sep 04, 2017 1:35 pm

78wkndr wrote:
Sun Sep 03, 2017 7:35 pm

I just had my alternator rebuilt by a local shop.

I originally thought the wire shorted because of a pinch/rub situation but the rebuilder said a nut had fallen off internally and shorted the positive to the alternator housing. This resulted in the hot wire to the starter melting very, very thoroughly.

Old school alternator rebuild guy was appalled at the shitty quality of the rebuilt alternator I presented him so he rebuilt it properly with parts from it, a second alternator I had, and new parts as needed.

Somewhat unrelated but...but it cost about $140 to rebuild it but I happily paid a bit more to have somebody who seemed to give a damn do the work.

Ultimately I purchased a new alternator wiring harness through bus depot. Took a while because they were out of stock.
You should be aware of an ongoing problem with rebuilt Bosch bus alternators having a too-long stud that causes an internal short. Chief symptom is usually a melted alternator wire.
It has been discussed on numerous threads in the Bay Window forum over on TheSamba. A search in that forum should turn up some hits pretty quickly.

There is also a fellow over on TheSamba with the nickname "thatvwbusguy" who sells custom-built harnesses for our vehicles. I have one that he made for m Vanagon, and it's of first-rate quality. He's also quite a nice guy to communicate with and is extremely knowledgeable on the minutia of VW electrics.
'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

78wkndr
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Re: Western Pennsylvania visit

Post by 78wkndr » Mon Sep 04, 2017 5:39 pm

Actually I learned the too long stud problem some years ago. I still have an alternator tin with I nice electrically burnt hole in it.
It seems the current (no pun) problem was as a result of an actual nut liberating itself and creating a positive to ground short.
The alternator in question was rebuilt maybe 20 years ago but had only seen maybe max. 10k miles accrued....well...19 years ago.

I did contact thatvwbusguy to discuss an alternator harness but he didn't have and couldn't get (thus far) the low profile boot to protect the pos. terminal.
I called him on a Sunday and we discussed it at length.
So, yes super super nice guy.
He was in contact with Scott at german supply trying to work it all out...

In the meantime Bus depot emailed me to say that they had harnesses back in stock so I just went with that. I just wanna get the kids back behind the wheel...hehe.
It seems reasonably robust and I'm satisfied so far.

Mini rant.....Global economy, cheap consumers, throw away culture......it's what we get.
..blend in a bit of impatience.
Yikes.
-78wkndr-
1978 westfalia tintop bus 2.0 FI

78wkndr
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Re: Western Pennsylvania visit

Post by 78wkndr » Sat Sep 09, 2017 10:16 am

I just replaced my s-boot and also the brake booster wye.
There was no indication that booster wye was leaking but I decided to replace it too because the old one was pretty beat.

Unfortunately there has been only a tiny improvement.
....I have enough time to jump out and run back to fiddle with the AFM wiper before The engine dies where as before I needed and assistant to start the bus while I fiddled.

Basically the wiper still needs to be coaxed counterclockwise an 1/8" to 3/16" to get the engine to idle.

All hoses are intact and attached.

Thoughts?
-78wkndr-
1978 westfalia tintop bus 2.0 FI

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Re: Western Pennsylvania visit

Post by 78wkndr » Sat Sep 09, 2017 11:15 am

Most likely unrelated but, should the wiper contacts slip off of the board when they are in their "rest" position, ie. the engine is off?
I just noticed that mine drop off of the board very slightly when the arm is fully seated in the clockwise position.
image.jpg
AFM
-78wkndr-
1978 westfalia tintop bus 2.0 FI

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Amskeptic
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Re: Western Pennsylvania visit

Post by Amskeptic » Sat Sep 09, 2017 7:13 pm

78wkndr wrote:
Sat Sep 09, 2017 11:15 am
Most likely unrelated but, should the wiper contacts slip off of the board when they are in their "rest" position, ie. the engine is off?
I just noticed that mine drop off of the board very slightly when the arm is fully seated in the clockwise position. image.jpg
No.
And that is why your engine is running so poorly. For reasons you and I do not know of, the wiper has slipped on the flap shaft, causing this abysmal idling and lean running.

You are hereby permitted to fix the damn thing.
With engine off, loosen the little screw in the recessed elongated slot that holds the wiper to the shaft.
Move it exactly as much as you had to move it previously to get it to idle.
Lightly secure the screw.
Count the number of turns required to seat the mixture screw and (let me know what that number was) bring it back 3 1/2 turns.
Go start the engine, which will idle normally.
After the engine is thoroughly warm, you may adjust the wiper so that there is a very small-but-noticeable increase in rpms when you nudge it counter-clockwise at idle.
Now, I am guessing, the wiper will park about 1/4" from the edge of the board.

If the fuel pump should continue to run when the engine is off (i.e. shut off engine, turn on ignition-only and listen for the fuel pump), you will need to carefully bend the silvery wire that is supposed to open the fuel pump contacts barely 1/16" when the wiper is parked.
YOU CAN DO IT!
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

78wkndr
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Re: Western Pennsylvania visit

Post by 78wkndr » Sun Sep 10, 2017 7:44 am

The idle mixture screw was 2.5 turns out since we adjusted the AFM back in June.

I turned it out another full turn to 3.5.
The screw holding the wiper was definitely a bit loose.
Not enough to adjust the wiper without additional loosening but clearly not tight enough.

In retrospect I'd say the progression towards lean was slow and steady...until the last drive when the air vane got a nice backfire bump which was all it needed to push the wiper way outta whack.
Maybe.

The alternator event kinda threw me off because I figured I must have jarred something when putting everything back together.

After replacing the S boot I tried turning the mixture screw all the way in to see if it would run but that only yielded slightly better idling.
That, combined with new and/or thoroughly inspected vacuum components should have caused me to suspect something else.

Anywho...
Mixture screw out 3.5.
Wiper adjusted to happy idle with a slight counter-clockwise nudge.
Minor adjustment to the fuel pump shut off lever resulting in a 1/16" gap between the contacts with engine off.

Bus is running well again.
:cheers:
-78wkndr-
1978 westfalia tintop bus 2.0 FI

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drober23
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Re: Western Pennsylvania visit

Post by drober23 » Mon Sep 11, 2017 3:26 am

Woo hoo! I had a backfire cause my AFM adjustment to slip before too. It was pretty frustrating to sort out at the time, because I did not suspect that it could happen.

Good job on getting it running nicely again!
DJ

'75 Westfalia, '79 Deluxe
(plus more busses than sense)

In a time of chimpanzees I was a monkey

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Amskeptic
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Re: Western Pennsylvania visit

Post by Amskeptic » Mon Sep 11, 2017 9:37 am

78wkndr wrote:
Sun Sep 10, 2017 7:44 am
Bus is running well again.
:cheers:
YOU CAN DID IT!
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

78wkndr
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Re: Western Pennsylvania visit

Post by 78wkndr » Mon Sep 11, 2017 12:57 pm

Thanks! for your help Colin.
-78wkndr-
1978 westfalia tintop bus 2.0 FI

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