Speedometer issues 51 F1

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Jan 22, 2010 | 01:28 PM

Rokcrln

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From: Winters Ca

Speedometer issues 51 F1

I just put in a speedometer cable in my son's F1 and it all worked great until I got on the freeway. I was doing about 70-75 and all of a sudden the speedometer pegs out and start winning. I pull over and unscrew the cable and drive back home. I have done some research and found that most speedo's are Eddie current style but no info on how to clean or fix my problem. Our truck sat in a barn since the early 60's with out the speedo being hooked up so I am assuming it is just dirty and needs to be cleaned or lubed.

Does anyone have info that might help me in fixing the above problems?

Thanks for any info you might have on this subject.

Kevin
LFD Inc.

Jan 22, 2010 | 02:07 PM

ALBUQ F-1

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From: NM

These are simple magnetically-coupled units, magnets spin inside a drum with magnets of its own. Every time the rotating magnets pass by the ones on the needle drum, it gives a "tug" on it. The bearings (bushings) for the drums get worn and sloppy, one drum touches the other and it sends the needle to max. They can be rebuilt, but as Julie noted in a similar thread, they were used in parcel trucks (bread vans) well into the '60's so there are new, used, and (I believe) repro units available for under a $100. Check fleabay and swap meets. I got a brand new Ford unit at a swap meet for $20 !!

Jan 22, 2010 | 02:29 PM

Rokcrln

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From: Winters Ca

Thanks for the reply, I was just out in the shop checking things out. I pulled the speedo apart and lightly blew out the dust and flakey paint (from the light housings) and then took a small piece of speedo shaft in my air drill and tired it out. It was working great until I pulled or pushed on the shaft then it went all crazy again. If I stopped and started with out moving the drill it went smooth and steady but again if I moved the drill/shaft it would go nutz. So in looking at the female end bushing of the speedo drive I saw it looked like dried grease so I cleaned it off and put a drop of dura lube in the end and spun it again and it worked great even with moving the drill all over. So I thing I will get some speedo cable lube and use a small amount of it on the end bushing and see how it does. I can't see anything being warn out as this truck only had 45k original miles on it when it was barn'd and I would really like to keep the original one in place just because

Kevin
LFD Inc.

Jan 22, 2010 | 02:41 PM

51PanelMan

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From: San Jose, CA

They're real easy to take apart and clean. Check the teeth. Keep in mind that trucks barely went over 55 mph back in the 50s.

I would get the same sound when I'd get my Panel into the 50 mph range.

By the way, bring the speedo cluster assembly with you to my house on Sunday. I can reset the odometer to all zeros for you if you'd like. It should only take a few minutes.

I just reset one a few weeks ago from a cluster I pulled out of a 52 Parcel (bread) van.

Jan 22, 2010 | 02:54 PM

Rokcrln

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From: Winters Ca

Quote:

Originally Posted by 51PanelMan

Thanks for the info and I did look over all the teeth and their is only a very slight wear pattern on the gears and everything is nice and tight and that tells me it probably was just the paint flacks and dried up grease. Thanks for the offer to reset the speedo but one of the reasons I want to keep the original one in the truck is because of how low the miles are.

See you Sunday!

Kevin
LFD Inc.

Jan 22, 2010 | 02:54 PM

ALBUQ F-1

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From: NM

I wouldn't use graphite lube on the speedo bushing, it could get into the speedo housing and ultimately onto the face of the gauge. There's an oil hole on the back of mine, right above the bushing.

Jan 22, 2010 | 03:24 PM

Rokcrln

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From: Winters Ca

Cool thanks! Mine does not seem to have an oiling hole but the half drop of duralube has really free'd things up. Before I could feel the drag with my fingers turning the bushing and not it is smooth as silk. Just for info I did not put a drop down into the bushing I put a drop on the out side of it and used a shop towel and wiped it in and around the bushing. The towel was almost black from the old dried grease that came off as I did this. Should be good to go now.

Kevin
LFD Inc.