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Found the short

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Moseso

Moseso

Jedi Knight
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As reported earlier, about 1/2 hour after successfully wiring my dash and checking everything (it all worked), my car began to blow the ignition switch fuse when the switch was turned on. I had been moving stuff around, so I figured the temp gauge tube was probably making an unauthorized contact behind the dash. I pulled the center plate out and decided, "maybe," so I moved the tube well away from any potential hot spots. Replaced the fuse. Turned on the ignition. *Pifff* One more fuse gave it's life in the line of duty.

So I took my continuity buzzer and determined that the side of the fuse box holding all the green accessory wires was shorted to ground. I pulled the four wires and found the one that was grounded. A lucky first guess showed me that that was the one connected to the wiper motor. Rats! It worked before -- but it's sure shorted to the case now. So I guess I dismantle it again and see if it's something easy and stupid, or if it has to be rewound.

In other news: My new water pump arrived today and I got everything put together enough to finish my cam break-in run! Tires arrive next Tuesday. It could be just another two or three weekends til it hits the road for shakedown cruise #1. (Probably with no windshield wipers yet.)

:driving:
 
Moseso said:
A lucky first guess showed me that that was the one connected to the wiper motor. Rats! It worked before -- but it's sure shorted to the case now. So I guess I dismantle it again and see if it's something easy and stupid, or if it has to be rewound.
Click to expand...
Before you take it apart, check to see if you got the wires interchanged on the terminals. The park switch shorts one of the power terminals to ground; obviously you don't want the green wire on that terminal.

Sorry I don't have the info handy as to which terminal is which.

Obviously (I hope) the motor presents as a very low resistance, but hopefully you can make it out with a ohmmeter. Or just swap the wires and offer another fuse to the Prince of Darkness
grin.gif


I'm also assuming you know that Lucas fuses are rated differently than American fuses. An AGC 20 makes an acceptable (and less expensive) substitute for the original Lucas 35 amp.
 
Good idea -- thanks!
The initial tests of the wiper motor demonstrated that the park switch was not working. I blamed a lackluster solder joint where the wire park attaches to the park switch terminal. Perhaps it has decided to conduct electricity now, making your guess a good one. I'll check into it!

I do know about the fuse ratings, thanks. The very last Lucas fuse is in the holder now. Maybe I'll save it until after the test period is over.
 
Terminal 1 is the one that (should) get shorted to ground by the park switch. So green goes on terminal 2. Unless of course someone has rewired the motor.
 
Randall --
Where do you find room in your head for so much arcane TR lore?
You were entirely correct.
As long as the park switch wasn't conducting, it made no difference which terminal was which -- the motor being, as you have pointed out, a universal motor.
As soon as the park switch decided to work, it shorted my misplaced power wire to ground.
Right after reading your post and responding to it, I went out to the garage and tested your hypothesis. Now I can say, "I've found the short -- and FIXED it!"
Now I just need it to rain, so I can use my entirely functional wipers.
 
Trust me, you aren't the first to make that mistake !
 
So, is this one of those, "Don't ask me how I know this," issues?
 
Well, not exactly ... I've just seen lots of others make that particular mistake.

But I've made lots of other blunders (my favorite is leaving the rotor on the fender after changing points), so don't feel special
grin.gif
 
Moseso said:
Randall --
Where do you find room in your head for so much arcane TR lore?
Click to expand...

We are definetly lucky having Randall on this forum. I've learned a bunch of stuff from his insightful and comprehensive posts.

:thankyousign: Randall for all help you have given us. :cheers:
 
:iagree: :thankyousign:

I, too, have learned much from Randall for which to be grateful...
 
I want to adopt him
But his price is probably too high. :laugh:
 
DNK said:
I want to adopt him
Click to expand...
I think my wife might object!

OTOH ... how many parking spaces do you have ? I've already got 4 Triumphs plus a reliable car (no room left in garage or driveway), and there's this Spitty on Craigslist calling my name
grin.gif
 
1300 sq. ft of garage and a lot of drive way




problem is there is a Wedge a 6 and Asto Van and an Accord already in there.
And my daughter is getting the Accord when my wife gets a new car next year.
 
1300 sq. ft. of garage???
I'm only 58. You could adopt me...
 
You know ya made it when your garage is bigger than your first house.


Still trying to talk my wife into another 600 sq. feet.
 
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