Tach cluster- tach not working

[Skrapbob]

Finally got around to installing my JY tach cluster. Switched all of the bulbs out to red LED's and synched up the odometers. The needles have been painted white. I left the plastic cover off and adjusted the speedometer needle to my gps.

The tachometer does not work! The lights and all of the other gauges are working perfectly. Am I missing something. Do I need to do something under the hood to make to send a signal to the yacht?

[TominMO]

If you have an 88 or 89 Festy, you won't have the wire going from the tach to the black plastic connector on the back of the cluster. I think it's pin I on the connector (the wire inputs are labeled A - L, on the wire side of the connector). You will have to run a separate wire from the ignition module directly to the connection on the cluster's greenboard. Trace the pin on the greenboard (#9 I think) to where it goes. That's where you connect the wire.

Edit: The greenboards on orange tach clusters are better labeled than the white ones, BTW.

[Skrapbob]

Thanks TominMO,

I found that a diode was shorted against a hot wire inside the tach gauge. I cleared it and it works now.
Can't seem to get it to work correctly though. I set the tach needle to zero then started the car and the needle doesn't move off zero until I rev the engine. I then set the needle to bottom out at about 800 rpm (aprox idle for auto trans?) but then it shows the engine revving all the way up to almost 8000 before shifting. Way past the 6200 redline.
The speedometer needle also has to be set well below zero also to read accurately at 60 mph.
I think I am gonna give up and just reinstall the original cluster

[TominMO]

Thanks TominMO,

I found that a diode was shorted against a hot wire inside the tach gauge. I cleared it and it works now.
Can't seem to get it to work correctly though. I set the tach needle to zero then started the car and the needle doesn't move off zero until I rev the engine. I then set the needle to bottom out at about 800 rpm (aprox idle for auto trans?) but then it shows the engine revving all the way up to almost 8000 before shifting. Way past the 6200 redline.
The speedometer needle also has to be set well below zero also to read accurately at 60 mph.
I think I am gonna give up and just reinstall the original cluster

Do you have oversize tires, which will throw off the speedo?

[Skrapbob]

I just bought four new 155/80/12 but I was surprised at how accurate the original speedo was with these tires according to the gps. After seeing the tach cluster with the red LED bulbs at night I would really like to make this work. Maybe I fried something when I was testing the bulbs on my bench or maybe damaged it by pulling the needles to remove the faceplate.

I am such an idiot! As I am sitting here writing this I just realized I think I know what I did wrong. While the needles were off I decided to paint them white with some touch up paint from my truck. I think the added weight of the paint is causing a heavy condition and not allowing the gauges to work as they should.

I need a new set of needles

[91mcnasty]

if you dont mind me asking, How'd you get your needles off? is it just a snap on snap off kind of thing?

[Skrapbob]

You just gotta tug. A small pair of pliers helps a bunch. The small needles were the toughest to remove. If you can use a set of needle nose to hold the rod while you pull is best. I didn't get the small needles off until after the faceplate was removed.

[Skrapbob]

WARNING! The needles are VERY brittle. You can almost break them by just staring at them.

[sc72]

New 12's

You mentioned you bought so new 12's what did you pay for them. Thanks

[TominMO]

I just bought four new 155/80/12 but I was surprised at how accurate the original speedo was with these tires according to the gps. After seeing the tach cluster with the red LED bulbs at night I would really like to make this work. Maybe I fried something when I was testing the bulbs on my bench or maybe damaged it by pulling the needles to remove the faceplate.

I am such an idiot! As I am sitting here writing this I just realized I think I know what I did wrong. While the needles were off I decided to paint them white with some touch up paint from my truck. I think the added weight of the paint is causing a heavy condition and not allowing the gauges to work as they should.

I need a new set of needles

I painted mine with luminous paint (didn't do much). No change in how they functioned.

[Skrapbob]

hercules 155/80/12 $60 each installed

[sc72]

^^^Thanks, but where did you get them.

[Skrapbob]

^^^Thanks, but where did you get them.

I bought the tires at a local hercules dealer here in town.

I finally got around to cleaning the paint off the needles and reinstalled the cluster today. It works correctly now
Spray paint would probably be ok on the needles but brushing it on will create heavy needles and will mess up the calibration.
A kitchen fork works great for removing the needles in the cluster