What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

VM1000 Tacho function

penguin

Well Known Member
The tacho function in my VM100 is becoming very intermittent, over the last few hours it has gone from the occasional glitch to not working most of the time, reverting to the hobbs number or showing a rapidly changing non-sensical number. Does anyone have any experience with these systems to suggest a cause/fix? Are the mag sensors available for any other sources?
The wiring from the Slick mag sender looks fine. The other indications are working.
Thanks in advance for any help.
Pete
 
I just had the same problem with my VM1000 and Slick mag. The sensor is glued into the vent plug. I was surprised it stayed in as long as it did the way it's made. I glued it back in place with a small amount of silicone on the diameter and tapped a 6-32 hole beside the sensor (not the vent hole) and placed an aluminum tab with a bend over the edge of the plug hex so it wouldn't rotate. Installed the tab with silicone under the tab on top of the sensor to help hold it all in place.
Ultra Grey silicone dry's firm and holds strong to aluminum. It's not coming out again.
There's a slight oval depression in the bottom of the vent plug that can be matched up with the oval on the end of the sensor for orientation. I used a non magnetic stainless 6-32 screw just in case a ferrous metal screw might cause a problem.
Good luck, I hope this is your problem. Easy fix.
Sure wish Reggie was back. I'm dreading that day...
 
I think the first thing to look at is the battery. How old and what type, there were three versions over the years and the first, original from what I recall, wasn't good for more than 3 years. The current replacement is good for at least 10,, assuming you can verify that it isn't a "new-old-stock" that's been on the shelf for several years.

M48T02-70PC1 (or -150PC1)

I got mine from Digi-Key for about $30
 
I just replaced my rpm sensor on my VM1000C with a UMA from Stein. Works great. Little over $100.
 
Thanks, Jerry, interesting thought.

Derrick - thanks for the P/N, DigiKey is a real pain to use outside of the US because of your daft (perhaps paranoid) export rules and the incompetent drop downs used on some of these sites.
 
Back
Top