Tach error

Rut Row · Mar 20, 2019

On my well used but new to me L2250, the tach wasn't working when I got it. Today I took the dash apart thinking the cable was broken. Imagine my surprise to find the cable disconnected. I connected the cable and started the tractor. It showed the engine idling at 1500 RPM which was definitely not right. When I rev'd it, the tach went past 3,000 RPM and that was absolutely not right.

Has anyone experienced this? I'm wondering is a previous owner replaced the dash and it has the wrong tach.

North Idaho Wolfman · Mar 20, 2019

Highly unlikely that the tack is out of something else, since not may others would cross over.

The Tack is magnetically driven and it more than likely just damaged.

JeffL · Mar 20, 2019

My B7200 is not used much and after sitting for two months I started it and the tach did same as yours. After an hour of true 1500-2000 rpm running the tach returned to normal, and for the remainder of the winter. Sign of impending doom? Rust or dirt causing friction? Who knows.
From my British car days I do know a jumpy high reading tach is a sign of a dry cable. The cable is sticking and winding/unwinging. Removal, cleaning, and light grease on the core will cure the problem. No action will eventually break the cable. Jeff

Rut Row · Mar 21, 2019

Thanks. I'll lube it and let it run for a while. All else failed I'll install a Tiny Tach.

D2Cat · Mar 21, 2019

Think I'd try some powered graphite for lube in the housing. Using a grease could cause problems in extreme cold weather.

85Hokie · Mar 21, 2019

Rut Row said:
Thanks. I'll lube it and let it run for a while. All else failed I'll install a Tiny Tach.

Rut,

this will sound crazy.....

can the needle be moved on the shaft?
IS there a stop pin at zero RPM?

it seems like it is off something like 500 rpms

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Tach error

Rut Row

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North Idaho Wolfman

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JeffL

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Rut Row

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D2Cat

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85Hokie

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