'71 Bus Fuse #8 Pop, Pop, Pop

[jblair630]

I finally got around to diagnosing Phred's latest issue. Like me, he waited until after we got finished moving before saying "Maybe we worked a little too hard there bucko. Now that we're done, we got some issues that need dealt with."

After trying to find out why Phred wouldn't start, I discovered that Fuse #8 had blown. I replaced it and tried to start but the fuse popped again within a second or two.

According to Bentley, the wire goes from the solenoid to fuse #8 to terminal 30 on the emergency flasher switch.

I am looking for suggestions on what I might do next to effectively test the solenoid and/or the emergency flasher switch.

I found these threads and they have given me some ideas but any other thoughts will be most welcome.


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Thanks

[dtrumbo]

Refresh my memory about what the bus does(n't) do when you try to start it. Does the engine turn over, but not start or does it not even do that.

My first synapse-fire sez that the nut on solenoid that connects the battery cable and the big red/white wire is loose and therefore not making a good connection.

[Amskeptic]

Dick, I am so out of time here, but Jeffrey needs a little guidance.

The ignition switch gets its power from #30 (hot) from the emergency flasher switch. I think it might be a stupid out-of-place wire in the emergency flasher area. Even a tug on a wire while trying to do something all together different under there can move the terminal into contact with bad things. It is a rat's nest. Upgrade the area with a little piece of well-engineered heavy card stock, like a business card or shirt cardboard.

Can you mentor him through, Dick? I am going to be off the forum a few days.
Colin

[dtrumbo]

The ignition switch gets its power from #30 (hot) from the emergency flasher switch... It is a rat's nest.

So it sounds like Phred isn't stock (If he was, I guess he'd be Fred).

Can you mentor him through, Dick? I am going to be off the forum a few days.
Colin

Will do, Capn'! Safe travels!

[dtrumbo]

So Jeffery, Colin sez your ignition switch gets it's power from the hazard switch. This is not how the wiring diagram says it should be, but it could certainly explain the whole fuse-popping thing. As Colin suggested, poke thy bean up under the dash and see if the big red wire(s) that are hooked to your hazard switch could possibly touch anything they shouldn't. I'll wait while you do this and I'll know when you're done because I'll be able to hear your scream of pain all the way across the 2,134 miles that span between us. Doing this with a hernia is probably next to impossible, but do what you can and don't push it.

Let me know what you see besides stars.

[vdubyah73]

VW flasher switches are known to fall apart and cause all kinds of wonky things with electrics. The two times it has happened to me, all I had to do was push the guts back into place and zip tie it together securely.

[jblair630]

Due to Z coming down with a very nasty stomach virus, I had to put off any work on Phred until today. Looks like Colin and Trumbo were both right...

The easiest thing to get to was the emergency flasher switch. Since I only have a big hole where the radio is supposed to live, getting to the switch only required taking off the knob and the collar that holds it in place on the dashboard. Then it was very easy to move it around and look at it through the aforementioned hole. Sure enough, the tab where 30 connects had been bent over and was in contact with the tab next to it. I separated them and wrapped 30 in a bit of electrical tape to make sure it stayed separated. Put it back together and all is well there.

Thought I would check out the solenoid connection while I was at it and sure enough, lots of dirt and junk. I cleaned the connections and put it back together. Engine started right up. Hoorah

But not so fast... I wanted to make sure it was well and truly fixed so I turned off the engine and when I tried to start again I got that sickening clunk that says that the starter has thrust but is not spinning the flywheel. Crap.

Since there was so much dirt on the solenoid contacts I thought there may be dirt and junk in the starter as well. I took the starter out and started to disassemble. That sucker had dirt and crap all through the inside. Surprising, since they are supposed to be pretty much sealed. I have been cleaning the innards and started to put it back together when my hernia said "Enough for one day or you are going to be really sorry." I may not listen to my body very often but THAT I listen to.

I will finish putting the starter back together tomorrow and then test to see if it will run. I am not holding much hope but I just feel like I have to see it through.

I'll update when there's more news.

Thanks all.
Jeffrey

[dtrumbo]

Great news, Jeffrey! I assume that even though the starter still has issues, the fuse has stopped blowing since you insulated the terminals on the hazard switch?

Someday, after all of this is sorted out, you can restore the wiring back to its original condition. Makes the Bentley and associated wiring diagrams so much more useful!

Congrats, and I'm glad the hernia cooperated with getting Phred fixed.

[Amskeptic]

Great news, Jeffrey! I assume that even though the starter still has issues, the fuse has stopped blowing since you insulated the terminals on the hazard switch?

Someday, after all of this is sorted out, you can restore the wiring back to its original condition. Makes the Bentley and associated wiring diagrams so much more useful!

Congrats, and I'm glad the hernia cooperated with getting Phred fixed.

Thanks, Dick.

Damn, I'm good. (sort of, it was '69 and earlier that powers ignition from haz sw)

Good luck Jeffrey!

Colin

[zblair]

I just spoke with J and he is very slowly, very carefully and very mindfully replacing the starter and the solenoid. He told me the starter was dead, but said that, "So far, so good with Phred"

[dtrumbo]

(sort of, it was '69 and earlier that powers ignition from haz sw)

Sort of... 68-70 the ignition switch gets power from the unfused terminal 30 of the headlight switch, not the hazard switch. Starting in 71, the ignition gets power from the unfused side of the fuse box which is also were the headlight switch gets its power. In any case, the ignition switch NEVER has a fuse inline. I'm guessing the reason is that way your engine doesn't just suddenly stop running, perhaps at a VERY BAD time, because of a blown fuse.

[jblair630]

As Z said earlier, I was being very slow and careful about doing the repair work. I didn't want to spend the entire day tomorrow laid out. I'll be very glad when the surgery is done on Friday and I can start recuperating back to a normal life.


Phred is up and running. The starter and solenoid replaced and then a complete oil change and tune up. Took a trip around the block and all seems right and proper.

The more I learn, the more I realize I don't know. In a way that's good since if I know I don't know something then I can look it up or ask y'all, etc. It's the things you don't know you don't know that can get you into trouble. I'll let you think about that one for awhile.

Thanks
Jeffrey