Re: (ET) E20 Rookie - more questions

["steves" <ssawtelle fcc net>]

> I can drive the tractor around - brilliant!

Excellent!

>But it totally lacks power - I can only move up any kind of slope in the
lowest gear.

Do you have speed and no power (field weakening), or no speed and no power
(amature current)?

As noted in other responses, see if the armature resistors are hot (big
strap resistors over charger) when running in crusie control (optimum
power). I find power is much diminished at low throttles (low armature
current).

Also if I read the schematic right, the field circuit is effectively
bypassed in reverse. See if you get more power in reverse. If so then it 
may
be the field weakening circuit (which should kick in only at higher
throttle).

> I've tried to figure out the operating sequence of the relays and just 
> get
confused.

The E20 is the most complex of the ET line and is confusing. The service
manual has some good troubleshooting stuff. Do you have the schematic?

> Is there something else in series with the relay coil circuits?

A lot of connections and diodes in places. Either can cause trouble. Check
voltage across the coils when they should be activated. As you have found
out there are mechnaical and electrical issues.

> The cruise control is a mess - I replaced the 4 diodes as one was 
> cracked,
> The small transistor on the board has melted some time in the past - Is
this
> likely to cause other issues with the motor operation?

- I wouldn't think so , but I haven't studied the CC much.

> Should one of the relays swich off as the pedal moves down (to switch out
> the resistors)?

There should be a lot of relay action going on as throttle position 
changes.

- SteveS