Bucking, lurching leads to no camping and bummed out kids

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aopisa
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by aopisa » Mon Jul 23, 2012 5:37 am

SlowLane wrote:Not to flog a dead horse, but ... did you check the AAR elbow? Inspect the S-boot for cracks? Check the seal of the valve cover gaskets?

Are you using points, or do you have a pointless ignition?
Believe me, I have been flogging the same horse. I have checked for vacuum leaks several times including the AAR elbow. I still keep thinking I may have missed something somewhere. I have only checked the S boot while in place. Should I remove it to give it a once over? Valve covers look tight and well seated.

I am running a points replacement. I do have a new set of points and a condenser, but do not know how to swap it out. That is on the Colin list for September. Although from what I have read, these units are pretty reliable and when they do fail it's generally all at once. Plus, it's finally time to invest in a Tach/Dwell meter and timing light.

My bus technical knowledge is still in its formative stages, but I am determined to solve this as I still think it is going to be something relatively simple.

Thanks.
1977 Westy 2.0L F.I.

Flow with whatever may happen and let your mind be free. Stay centered by accepting whatever you are doing. This is the ultimate. - Chuang Tzu

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SlowLane
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by SlowLane » Mon Jul 23, 2012 9:25 am

aopisa wrote:Believe me, I have been flogging the same horse. I have checked for vacuum leaks several times including the AAR elbow. I still keep thinking I may have missed something somewhere. I have only checked the S boot while in place. Should I remove it to give it a once over?
I think that would be prudent. The S-boot isn't difficult to remove, and you really need to be able to inspect it at all angles under good light.
aopisa wrote: I am running a points replacement. I do have a new set of points and a condenser, but do not know how to swap it out. That is on the Colin list for September. Although from what I have read, these units are pretty reliable and when they do fail it's generally all at once.
Knowing how to install and adjust points is definitely a must-have in your budding skillset. You need to have that fall-back position if the pointless gizmo gives up the ghost.
aopisa wrote:Plus, it's finally time to invest in a Tach/Dwell meter and timing light.
Can I also recommend adding a diagnostic vacuum gauge to that list?
'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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aopisa
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by aopisa » Mon Jul 23, 2012 9:36 am

SlowLane wrote:
aopisa wrote:Believe me, I have been flogging the same horse. I have checked for vacuum leaks several times including the AAR elbow. I still keep thinking I may have missed something somewhere. I have only checked the S boot while in place. Should I remove it to give it a once over?[/qoute]
I think that would be prudent. The S-boot isn't difficult to remove, and you really need to be able to inspect it at all angles under good light.
aopisa wrote: I am running a points replacement. I do have a new set of points and a condenser, but do not know how to swap it out. That is on the Colin list for September. Although from what I have read, these units are pretty reliable and when they do fail it's generally all at once.
Knowing how to install and adjust points is definitely a must-have in your budding skillset. You need to have that fall-back position if the pointless gizmo gives up the ghost.
aopisa wrote:Plus, it's finally time to invest in a Tach/Dwell meter and timing light.
Can I also recommend adding a diagnostic vacuum gauge to that list?
I will inspect the S boot.

Do you have recommendation for a diagnostic vacuum gauge? How about a fuel pressure test gauge?
1977 Westy 2.0L F.I.

Flow with whatever may happen and let your mind be free. Stay centered by accepting whatever you are doing. This is the ultimate. - Chuang Tzu

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SlowLane
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by SlowLane » Mon Jul 23, 2012 10:34 am

aopisa wrote:Do you have recommendation for a diagnostic vacuum gauge? How about a fuel pressure test gauge?
Vacuum gauge: most FLAPS have something targeted at the home mechanic. Anything along those lines would be fine. Even if it isn't calibrated perfectly, it will allow you to see variations in vacuum. If you have money to burn, a Fluke PV350 would be the coolest toy. It's on my wish-list. :wink:

Most hobby-level vacuum gauges are also fuel-pressure gauges, but they're only suitable for use with low-pressure systems (up to 5 psi). The L-Jet system has pressures up to 36 psi, so you need something like this gauge sold by German Supply.

Forgot to ask: how old are your distributor cap, rotor and ignition wires?
'81 Canadian Westfalia (2.0L, manual), now Californiated

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aopisa
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by aopisa » Mon Jul 23, 2012 10:56 am

SlowLane wrote:
aopisa wrote:Do you have recommendation for a diagnostic vacuum gauge? How about a fuel pressure test gauge?
Vacuum gauge: most FLAPS have something targeted at the home mechanic. Anything along those lines would be fine. Even if it isn't calibrated perfectly, it will allow you to see variations in vacuum. If you have money to burn, a Fluke PV350 would be the coolest toy. It's on my wish-list. :wink:

Most hobby-level vacuum gauges are also fuel-pressure gauges, but they're only suitable for use with low-pressure systems (up to 5 psi). The L-Jet system has pressures up to 36 psi, so you need something like this gauge sold by German Supply.

Forgot to ask: how old are your distributor cap, rotor and ignition wires?
Thanks for the suggestions. I noticed that the vacuum gauges did not go high enough to handle the FI pressure. It looks like the German Supply gauge (currently OOS) lives permanently on the fuel rail?

Cap, rotor and wires are of an unknown age although they do not look ancient. I have owned the bus for 3 years myself. I have inspected the cap for visual defects. I believe I have a new set of wires I got form Bus Depot somewhere.
1977 Westy 2.0L F.I.

Flow with whatever may happen and let your mind be free. Stay centered by accepting whatever you are doing. This is the ultimate. - Chuang Tzu

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Re: Bucking, lurching leads to no camping and bummed out kid

Post by SlowLane » Mon Jul 23, 2012 11:14 am

aopisa wrote:Thanks for the suggestions. I noticed that the vacuum gauges did not go high enough to handle the FI pressure. It looks like the German Supply gauge (currently OOS) lives permanently on the fuel rail?
It isn't recommended to leave it on the rail permanantly. You just put it on there when you need to check the pressure. Otherwise leave the stock cap-screw in there. You wouldn't be able to monitor it while driving anyways, so leaving it on really has zero benefit, unless you have someone who is willing to hang over the open engine lid and watch it while you drive around (ie. Colin).
aopisa wrote:Cap, rotor and wires are of an unknown age although they do not look ancient. I have owned the bus for 3 years myself. I have inspected the cap for visual defects. I believe I have a new set of wires I got form Bus Depot somewhere.
My personal strategy is to eliminate any possible ignition gremlins first before moving on to fuel gremlins. You can't always see carbon tracks. Cap and rotor are easy to change and comparatively inexpensive. Use genuine Bosch or Beru parts. Make sure you get the correct rotor for your application (Federal and CA-spec rotors have different lnternal resistances).
'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: Bucking, lurching leads to no camping and bummed out kid

Post by TrollFromDownBelow » Mon Jul 23, 2012 11:25 am

I had very similar gremlins…haunted me for nearly two seasons! It was very maddening My problem was a Temp Sensor 11; specifically a bad sensor, and it constantly wanted to vibrate loose, also the shrink tubing at the base would loosen it's grip once it got warm which I suspect was a contributing factor to the poor connection. However, a couple of thoughts on your situation:

- Instead of guessing if you have a vac. leak, buy a cheap vac gauge and test – should have ~17-22 in of vacuum IIRC
- Switch back to points to eliminate the pointless system as a potential problem. IIRC you can set the gap static at .017 (about the thickness of a matchbook will do in a pinch).
- I’d spend $50 and replace cap, rotor, dist, wires and check the plugs. This is relatively inexpensive, and since you don’t know when it was last done, it will develop your baseline for regular maintenance.

If none of that works, then report back.
1976 VW Bus aka tripod
FI ...not leaky, and not so noisy...and she runs awesome!
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aopisa
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by aopisa » Mon Jul 23, 2012 11:32 am

SlowLane wrote:
aopisa wrote:Thanks for the suggestions. I noticed that the vacuum gauges did not go high enough to handle the FI pressure. It looks like the German Supply gauge (currently OOS) lives permanently on the fuel rail?
It isn't recommended to leave it on the rail permanantly. You just put it on there when you need to check the pressure. Otherwise leave the stock cap-screw in there. You wouldn't be able to monitor it while driving anyways, so leaving it on really has zero benefit, unless you have someone who is willing to hang over the open engine lid and watch it while you drive around (ie. Colin).
aopisa wrote:Cap, rotor and wires are of an unknown age although they do not look ancient. I have owned the bus for 3 years myself. I have inspected the cap for visual defects. I believe I have a new set of wires I got form Bus Depot somewhere.
My personal strategy is to eliminate any possible ignition gremlins first before moving on to fuel gremlins. You can't always see carbon tracks. Cap and rotor are easy to change and comparatively inexpensive. Use genuine Bosch or Beru parts. Make sure you get the correct rotor for your application (Federal and CA-spec rotors have different lnternal resistances).
Thanks. Your advice is followed up by another dumb question that I keep forgetting to ask. My bus was from CA before it came to the East Coast. How do I tell a CA bus from a Federal bus? Does this label on the engine hatch make it CA?

Image
1977 Westy 2.0L F.I.

Flow with whatever may happen and let your mind be free. Stay centered by accepting whatever you are doing. This is the ultimate. - Chuang Tzu

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aopisa
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by aopisa » Mon Jul 23, 2012 11:42 am

TrollFromDownBelow wrote:I had very similar gremlins…haunted me for nearly two seasons! It was very maddening My problem was a Temp Sensor 11; specifically a bad sensor, and it constantly wanted to vibrate loose, also the shrink tubing at the base would loosen it's grip once it got warm which I suspect was a contributing factor to the poor connection. However, a couple of thoughts on your situation:

- Instead of guessing if you have a vac. leak, buy a cheap vac gauge and test – should have ~17-22 in of vacuum IIRC
- Switch back to points to eliminate the pointless system as a potential problem. IIRC you can set the gap static at .017 (about the thickness of a matchbook will do in a pinch).
- I’d spend $50 and replace cap, rotor, dist, wires and check the plugs. This is relatively inexpensive, and since you don’t know when it was last done, it will develop your baseline for regular maintenance.

If none of that works, then report back.
Thanks. I have never done anything with the distributor except for adjusting the timing. I will have to check Mr. Bentley to see if there is enough for me to go on to do this. Sorry, but the only person around here with a bus is me. The only time I get practical hands on knowledge is from Colin once a year. Otherwise I am on my own. Even the Bentley assumes you have some kind of basic mechanical foundation in order to follow their instructions. Sometimes I lack that basic knowledge.
1977 Westy 2.0L F.I.

Flow with whatever may happen and let your mind be free. Stay centered by accepting whatever you are doing. This is the ultimate. - Chuang Tzu

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SlowLane
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by SlowLane » Mon Jul 23, 2012 1:05 pm

aopisa wrote:
Thanks. Your advice is followed up by another dumb question that I keep forgetting to ask. My bus was from CA before it came to the East Coast. How do I tell a CA bus from a Federal bus? Does this label on the engine hatch make it CA?

Image
Since the sticker specifically mentions California, I'd say it is CA-spec.
But I spoke earlier without checking. For 1977, there doesn't appear to be any difference in the ignition system between CA-spec and 49-state spec. See the Old Volks Home distributor page for details.
The differences in rotor resistance that I mentioned earlier are pertinent to the Hall-effect ignitions that VW started fielding on the 1979 bus.
'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: Bucking, lurching leads to no camping and bummed out kid

Post by vdubyah73 » Mon Jul 23, 2012 1:33 pm

brake booster, distributor vacuum can. booster or section of vac hose leaking up front? vac can on distributor, diaghram junk? more than 1 vac hose to vac can, are they hooked up right?

just seeing if something sticks
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by bajaman72 » Mon Jul 23, 2012 3:39 pm

I had a valve cover gasket suck in at the top. It didn't leak oil, but the vacume leak made the car run like crap for a while before it was discovered during a last ditch effort to re-adjust the recently adjusted valves :-/
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by aopisa » Wed Jul 25, 2012 7:37 am

Thanks to everyone for all the suggestions. I would really like to solve this soon as I have a big trip planned (Badlands, SD) which would be perfect for the bus and not as much fun in my regular car.

Here is a list of things I still need to check, some of which I will need to get the necessary tools/equipment to accomplish. Instead of chasing all over the bus, can someone help me put this into a logical diagnostic order?

-Test vacuum with a vacuum gauge (once I get one, where/how to I hook it up?)
-Switch back to points and condenser (not sure how to do this, yet)
-Replace cap, rotor and wires (just plug and play?)
-Check plugs
-Remove S boot and inspect for cracks (what else do I have to remove to get this out? I do not want to damage this NLA part, could not find Bentley procedure for removal)
-Check valve cover gaskets for leaks
-brake booster/hose
-Distributor vacuum can/diaphragm?

I think that's it. Thanks.
1977 Westy 2.0L F.I.

Flow with whatever may happen and let your mind be free. Stay centered by accepting whatever you are doing. This is the ultimate. - Chuang Tzu

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Re: Bucking, lurching leads to no camping and bummed out kid

Post by TrollFromDownBelow » Thu Jul 26, 2012 7:34 am

Do this first....

-Test vacuum with a vacuum gauge (once I get one, where/how to I hook it up?) As for where to hook it, any vac. line that fits and has good suction (put your finger over the end of it and check for suction) at idle.

As it will tell you if you need to look for these...

-Remove S boot and inspect for cracks (what else do I have to remove to get this out? I do not want to damage this NLA part, could not find Bentley procedure for removal)
-Check valve cover gaskets for leaks
-brake booster/hose

Personally I would switch back to points next, however, since you don't know how to do this (yet!), might as well do this next to set your baseline as it should be done anyways...

-Replace cap, rotor and wires AND plugs! :) (just plug and play?) - Yes, this is pretty much plug and play - would double check timing afterwards.

Then these two in this order.....

-Switch back to points and condenser (not sure how to do this, yet)

-Distributor vacuum can/diaphragm?
1976 VW Bus aka tripod
FI ...not leaky, and not so noisy...and she runs awesome!
hambone wrote: There are those out there with no other aim but to bunch panties. It's like arguing with a pretzel.
::troll2::

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aopisa
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Re: Bucking, lurching leads to no camping and bummed out kid

Post by aopisa » Thu Jul 26, 2012 8:04 am

TrollFromDownBelow wrote:Do this first....

-Test vacuum with a vacuum gauge (once I get one, where/how to I hook it up?) As for where to hook it, any vac. line that fits and has good suction (put your finger over the end of it and check for suction) at idle.

As it will tell you if you need to look for these...

-Remove S boot and inspect for cracks (what else do I have to remove to get this out? I do not want to damage this NLA part, could not find Bentley procedure for removal)
-Check valve cover gaskets for leaks
-brake booster/hose

Personally I would switch back to points next, however, since you don't know how to do this (yet!), might as well do this next to set your baseline as it should be done anyways...

-Replace cap, rotor and wires AND plugs! :) (just plug and play?) - Yes, this is pretty much plug and play - would double check timing afterwards.

Then these two in this order.....

-Switch back to points and condenser (not sure how to do this, yet)

-Distributor vacuum can/diaphragm?
Alright, I am off to the FLAPS or Sears to get some of the necessary diagnostic and testing equipment. Will report back. Thank you.
1977 Westy 2.0L F.I.

Flow with whatever may happen and let your mind be free. Stay centered by accepting whatever you are doing. This is the ultimate. - Chuang Tzu

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