Intermittent No Crank-1972 bus

[aeromech]

For the next guy reading this with the same problem. Take a battery jumper cable and connect one clamp to somewhere on your starter. Then the other clamp to either the bus frame or directly to the battery negative post. If the starter cranks then you’ll know that your problem is the ground connection between the starter and the battery.

Most electrical components have both a positive wire and a negative wire. Starters have just a positive wire. They need to be bonded to the transmission which is bonded to the frame via the ground strap pictured by Xevin on page one. As Steve said, the starter pad to bell housing must be clean and unpainted for this bond.

Funny thing…. As much as I love Eric at Transworks in El Cajon, he always paints the starter pad when he does a rebuild and when I get a trans from him I always have to remove that paint. I tried explaining it to him and he thought I was nuts.
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VW Type 2 1971 (3 ea.) 1978, 1969
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Capable of leaping tall buildings in a single bound

[SGKent]

[Tweed2863]

[SGKent]

[dodger tom]

[SGKent]

[Xevin]

[Tweed2863]

[airschooled]

1972 buses have a nonstandard (terrible) battery ground strap location in the engine compartment. That’s the first place I would clean and tighten the fasteners.

Robbie
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[Xevin]

[Tweed2863]

Well, I was able to get under the bus for a little bit before the rain and wind started. I did some of the easier suggestions due to the weather. I cleaned the ground strap, battery terminals and the positive cable end connected to the starter. It fired right up! I hope these were the issue and they are solved, but we all know how these VW's are. HA
I appreciate everyone's help and suggestions. I know this has been an intermittent issue and it may arise again. Fingers crossed.

Thank you everyone!!

[SGKent]

leave the hard start relay off the bus until you solve the issue or you are just adding one more variable to cause you issues. Fix the problem first.
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George Carlin:
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Skills@EuroCarsPlus:
"never time to do it right but always time to do it twice"

[lil-jinx]

there is a bushing that the starter shaft goes onto,i’m not sure but if it’s beat out it might cause this problem.as for the ground at the trans,many bus owners put a ground cable direct from the battery to the engine,many use the starter mount bolt for this ,my ground goes from the battery to the body then to the engine,the trans ground becomes redundant with this set up.
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https://www.thesamba.com/vw/forum/viewtopic.php?t=620186
https://www.thesamba.com/vw/forum/viewtopic.php?t=668799
1974 Bay Westfalia. she likes to be called Ethel.
1968 Dune Buggy sold dec 2024

1974 parts bus
A smart man learns from his mistakes,a very smart man learns from other's mistakes.

[Tweed2863]

[Tweed2863]

[lil-jinx]

you say you have power to the start terminal (the small blade terminal)when you turn the key ,to test that circuit ,you can remove the wire from the terminal and connect alight to it ,a head light would be good,then turn the key,that light should shine bright,if the circuit is good ,if the circuit is weak the light will be dim or not light at all.a wire with just one strand wil show 12 volts with a volt meter ,but it won’t carry a load .jumping the wire as i the picture that SGKent posted will bypass the ignition circuit,if it starts every time by jumping it at the starter ,then i would suspect the ignition circuit,if it don’t start when jumped it can be lack of battery pos power ,lack of ground or a faulty starter/solinoid.
dont over complicate electric circuits.
most circuits have just 4 components ,the pos battery wire the ground wire,a switch and the load,it’s like plumbing with pump pressure (battery) valves (switch) pipes(wires) and load,(container to receive the flow,and a drain(ground circuit)
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https://www.thesamba.com/vw/forum/viewtopic.php?t=620186
https://www.thesamba.com/vw/forum/viewtopic.php?t=668799
1974 Bay Westfalia. she likes to be called Ethel.
1968 Dune Buggy sold dec 2024

1974 parts bus
A smart man learns from his mistakes,a very smart man learns from other's mistakes.

[Tweed2863]

[SGKent]

most rebuilt starters come with the old solenoid. I do agree that it can be a battery cable, or connection to the battery or even the starter switch, intermittent solenoids are really common on air cooled VW's. Like I've helped people stranded in gasoline stations with the same issue more than once.

here is my classic troubleshooting photo on how to test where the problem is.

Green
White
Yellow

But like others super correctly suggested, I would check the cables and ground. Cables can rot on the inside and grounds can get corrosion too. Even batteries can have intermittent internal connections. Good Luck.

_________________
Canned Water - the new California approved parts cleaner (except in a drought in which case rub it with sand).

George Carlin:
"Most people don't know what they're doing, and a lot of them are really good at it."

Skills@EuroCarsPlus:
"never time to do it right but always time to do it twice"

[dodger tom]

so the new starter came with a new solenoid?

sorry if i missed it, did you clean the other battery cable and both battery posts?

don’t discount the ignition switch as a possible culprit.

also, could be the battery is on its last legs, er, if batteries had legs.
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1978 Champaign Edition 2 Westfalia
Would never find the time to keep up another classic air-cooled.

[Tweed2863]