Without schematics handy, here's some tips:
- the coil resistance should be around 80 ohms I think - power off and remove wires and measure terminals with a ohmmeter.
- any 200 grit or emerycloth to make contacts flat and equal.
- fingers should clearly move and make contact when excited.
- 36V should be on coil when excited
- check connections at circuit board
From: elec-trak-bounces cosmos phy tufts edu [mailto:elec-trak-bounces cosmos phy tufts edu]On Behalf Of John Rodencal
Sent: Monday, July 24, 2006 3:41 PM
To: elec-trak cosmos phy tufts edu
Subject: (ET) Speed Relays
I have two E15 tractors (no mower decks) Model AA and AE. I have been using parts from the AA and Bill Gunn to keep the AE running. Several days ago I experienced the "blue spark" which occurs when you go into reverse too quickly. These tractors have given me excellent service for 35 years, but I haven't mowed with them since 1984. I still do utility work around my plot every week, plow snow when available in Cincinnati (neighbors included), ro-till, drill and use the hedge trimmer. I even have a welder attachment which I have played with.
I purchased two relays from Bill Gunn in 2002 when I traded 3 mower deck motors (42") size for a selection of parts. I replace both relays after the "blue spark", speed control started to function until I reached the 2A contactor, then it welded two contacts on the reverse relay. Hind sight says I may have got two wires on the wrong terminals.
Using one of the better looking left over relays, I carefully (this time) wired the used relay according to the manual, but all it want to do is give the clicking sound and full current draw on gauge. The contacts on the old relay do not seem stuck, could the coil be bad?
With what grade paper/emery cloth do I sand the points?
Bill Gunn's relays are different wiring in that all the wires are on one end. Does wire 13 go to terminal A and wire 38 go to terminal B on the reverse relay?
I have little knowledge of electricity and have struggled to understand this tractor! Motor terminology throws me, but I would say I'm mechanically inclined. Not everything was lost when I took the GE Apprentice Training for machining metals.
Let's start with this much before we go deeper!
Will appreciate any help as long as I can understand it!