'78 Bus (manual trans) Loud THUD-SLAM shifting to reverse

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locoqueso
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'78 Bus (manual trans) Loud THUD-SLAM shifting to reverse

Post by locoqueso » Mon Sep 13, 2010 9:42 am

Recently I noticed a problem shifting into reverse. At first I thought that I just didn't have the clutch pedal fully depressed, but that wasn't the problem. After starting the bus I need to put it into reverse to get out of the garage. With the clutch pedal pushed to the floor, I get a loud "THUD" and it sounds like a slight grind as it slams into gear.

I don't know if it's related, but recently I’ve also noticed difficulty getting into 2nd and 3rd gear a few times and every so often it’s slow to get going from a dead stop. Those issues have not been consistent. With the engine off, shifting is fairly smooth going into all gears.

From what I’ve read, my first step would be to adjust the clutch cable by tightening it up. Right now I’d estimate the clutch pedal goes down at least an inch and a half before I feel any real resistance. I believe there should be about an inch before resistance is felt.

I have a 78 bus with about 145,000 miles. I plan to work on it sometime after work this week so I can make it camping this weekend. Am I on track with the details above? Any other troubleshooting advice?
1978 VW Campmobile (P-21) Westfalia - T2 2.0L F.I.- 151,000m
1982 Mercedes-Benz Estate Wagon (300TD-T) - S123 3.0L T.D. - 142,000m
1993 Dodge Maxi Van (190 SLF) InterVec Falcon - B350 Magnum 5.9L F.I. - 70,000m

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Randy in Maine
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Post by Randy in Maine » Mon Sep 13, 2010 10:32 am

Whilel you are under there adjusting the clutch cable freeplay to the spec, have a look at the bowden tube to make sure it is bent and the front weld has not broken.

Then (since you are under there anyway), make sure the transmission mounts are still nice tight and not broken. Check the ones on the top also.
79 VW Bus

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Amskeptic
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Re: '78 Bus (manual trans) Loud THUD-SLAM shifting to revers

Post by Amskeptic » Tue Sep 14, 2010 8:31 pm

locoqueso wrote:Recently I noticed a problem shifting into reverse.
I’ve also noticed difficulty getting into 2nd and 3rd gear a few times
With the engine off, shifting is fairly smooth going into all gears.

From what I’ve read, my first step would be to adjust the clutch cable by tightening it up?
Yes, and next step is to remove the engine and see why the clutch is not releasing correctly.
Colin
(p.s., do not drive with this symptom. Damage to the transaxle can and will occur)
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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locoqueso
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Post by locoqueso » Wed Sep 15, 2010 4:36 pm

Consider the bus parked until this is resolved. I'll crawl under there on Saturday to see if an adjustment fixes the problem. Thank you both for the advice.
1978 VW Campmobile (P-21) Westfalia - T2 2.0L F.I.- 151,000m
1982 Mercedes-Benz Estate Wagon (300TD-T) - S123 3.0L T.D. - 142,000m
1993 Dodge Maxi Van (190 SLF) InterVec Falcon - B350 Magnum 5.9L F.I. - 70,000m

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Amskeptic
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Post by Amskeptic » Wed Sep 15, 2010 7:39 pm

locoqueso wrote:Consider the bus parked until this is resolved. I'll crawl under there on Saturday to see if an adjustment fixes the problem. Thank you both for the advice.
I'll wait here.
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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locoqueso
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Post by locoqueso » Sat Sep 18, 2010 9:45 am

It's time for plan B. I was able to tighten the clutch cable about 1/4 inch, but it still grinds going into reverse. I don't think I could tighten it any more. There doesn't appear to be any more thread for the wing nut and I have about 1" of play in the pedal before I feel resistance.
1978 VW Campmobile (P-21) Westfalia - T2 2.0L F.I.- 151,000m
1982 Mercedes-Benz Estate Wagon (300TD-T) - S123 3.0L T.D. - 142,000m
1993 Dodge Maxi Van (190 SLF) InterVec Falcon - B350 Magnum 5.9L F.I. - 70,000m

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Amskeptic
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Post by Amskeptic » Sat Sep 18, 2010 5:02 pm

locoqueso wrote:It's time for plan B. I was able to tighten the clutch cable about 1/4 inch, but it still grinds going into reverse. I don't think I could tighten it any more. There doesn't appear to be any more thread for the wing nut and I have about 1" of play in the pedal before I feel resistance.
Plan B

Drop engine by lunch.
Remove pressure plate and clutch disk.
Clean and cross-hatch sand.
Clean/lubricate splines on input shaft and pilot bearing.
Test slide clutch disk on splines.
Reassemble by dinner.
After dinner, add a washer to the Bowden Cable at the transmission bracket so you will have more adjustment room on the end of the cable.
Test drive happily and go to bed.
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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locoqueso
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Post by locoqueso » Mon Sep 20, 2010 6:46 pm

That sounds like a good plan to me (IM sent). What would you suggest I have on hand for parts and tools?
1978 VW Campmobile (P-21) Westfalia - T2 2.0L F.I.- 151,000m
1982 Mercedes-Benz Estate Wagon (300TD-T) - S123 3.0L T.D. - 142,000m
1993 Dodge Maxi Van (190 SLF) InterVec Falcon - B350 Magnum 5.9L F.I. - 70,000m

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Ritter
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Post by Ritter » Sat Sep 25, 2010 11:11 am

locoqueso wrote:That sounds like a good plan to me (IM sent). What would you suggest I have on hand for parts and tools?
=D>

Always know when to cry "uncle."
1978 Westfalia 2.0 FI

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locoqueso
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Post by locoqueso » Wed Oct 06, 2010 6:23 pm

Sachs clutch kit, pilot bearing, flywheel o-ring, and front main seal have been orded from Bus Depot. They should be here by the end of the week.
1978 VW Campmobile (P-21) Westfalia - T2 2.0L F.I.- 151,000m
1982 Mercedes-Benz Estate Wagon (300TD-T) - S123 3.0L T.D. - 142,000m
1993 Dodge Maxi Van (190 SLF) InterVec Falcon - B350 Magnum 5.9L F.I. - 70,000m

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Vdubtech
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Post by Vdubtech » Mon Oct 11, 2010 3:17 pm

Grinding into reverse huh? Sounds familiar.......

http://itinerant-air-cooled.com/viewtopic.php?t=8531

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locoqueso
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Post by locoqueso » Tue Oct 12, 2010 6:24 pm

Yeah, that sounds like my problem. My parts arrived late last week and I plan to pull the engine on Sunday. Colin will be here Monday morning so all of a sudden I feel brave.
1978 VW Campmobile (P-21) Westfalia - T2 2.0L F.I.- 151,000m
1982 Mercedes-Benz Estate Wagon (300TD-T) - S123 3.0L T.D. - 142,000m
1993 Dodge Maxi Van (190 SLF) InterVec Falcon - B350 Magnum 5.9L F.I. - 70,000m

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Vdubtech
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Post by Vdubtech » Tue Oct 12, 2010 6:46 pm

He just left my place....he's headed in your direction. :-) It's amazing the havoc that little $8 bearing can wreak on your shifting.

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Post by locoqueso » Sat Oct 23, 2010 4:23 am

My problem turned out to be the flywheel O-ring. It looked more than a D-ring. Oil mixed in with the dust from the clutch and made a sloppy mess. After Colin left, it was smooth shifting for the old 78.
1978 VW Campmobile (P-21) Westfalia - T2 2.0L F.I.- 151,000m
1982 Mercedes-Benz Estate Wagon (300TD-T) - S123 3.0L T.D. - 142,000m
1993 Dodge Maxi Van (190 SLF) InterVec Falcon - B350 Magnum 5.9L F.I. - 70,000m

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sped372
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Post by sped372 » Sat Oct 23, 2010 6:31 am

Way to go. Now we can plan a get-together for next year!
1971 Karmann Ghia - 1600 DP
1984 Westfalia - 1.9 WBX

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