Re: (ET) crap - started mowing, and lost forward speeds

[Michael S Briggs <msbriggs alberti unh edu>]

Walt,
	It should be the forward/reverse relay I think (since when it has 
the problem, it's in all forward speeds, and sometimes also gets funky in 
reverse). It looks like there's a weak connection there - I'm not sure if 
a wire was put on wrong, I'll take a picture later (I have the service 
manual so I suppose I could go through that part of the schematics myself 
to see where certain wires are supposed to go, but there's a non-original 
wire on there without a number).
	On the blades - perhaps I should put the grass guides back on? I 
removed those metal hoops that go around the blades to guide grass out the 
back, which should presumably keep the grass from building up on the right 
blade. Perhaps that would help?
	When I took the Gator Blades off and put the original blades back 
on, that right one still cut poorly. WIthout those guides, does the right 
blade not cut well (with original blades) due to all of the grass from the 
other blades being thrown at it?
	The right motor definitely works, as far as spinning. It just 
doesn't seem to cut well. I was just assuming it might be due to that 
blade spinning slower.

Mike

--

--------------------------------------------------------------
Michael S. Briggs
UNH Physics Department
(603) 862-2828
---------------------------------------------------------------

On Mon, 24 Jul 2006, Konstanty, Walter (GE Indust, ConsInd) wrote:

> One relay is for Reverse/Forward and the other for field weakening.
> You'll should be able to see each work.  Field weakening comes on after 
> 3rd speed forward.
> Check the 2 wires that come from the coil and trace them back to the 
> circuit board - those are also trouble spots
> with bad connections.  Crimp/fix as required.
> Check relay fingers - contacts welded/corroded....
>
> Gator blade issue: mower motors turn same direction so all grass may 
> head for right motor so it "sees" higher loading, especially if you have 
> RHS discharge.  Make sure motor is not bound up or hot bearings.  Spin 
> blades by hand to check (power off).  Brushes not cause.  Check voltage 
> at each motor if possible when running but don't get close to blades. 
> If possible, measure amps with a clamp-on ammeter.  Remember, it's not a 
> brush hog.
>
> ...Walt
>
>
> -----Original Message-----
> From: elec-trak-bounces cosmos phy tufts edu
> [mailto:elec-trak-bounces cosmos phy tufts edu]On Behalf Of Michael S
> Briggs
> Sent: Monday, July 24, 2006 4:03 PM
> To: elec-trak cosmos phy tufts edu
> Subject: Re: (ET) crap - started mowing, and lost forward speeds
>
>
>
> Thanks for the tips from everyone (haven't had a chance to read all of
> them yet, since the classes I'm teaching had 5 hours of lecture today -
> bleah). A quick update though:
>         I found *where* the problem is, and was able to finish mowing.
> There's apparently a loose connection somewhere either on the panel that
> card 1 is on, or on one of the wires that connects to it. When I took out
> the screws and tilted that panel out to start debugging, with the tractor
> in neutral (seat switch bypassed), as soon as I pushed the speed switch
> forward, the motor started spinning, instead of the weird behavior I was
> getting. I closed the panel up, hopped back on, and tried driving - same
> weird behavior again. I found that wiggling that panel around I could get
> it into a position where it worked fine. So, apparently some wire
> connecting to the panel has a flaky connection, that is apparently
> creating a short (I think) at times.
>         I was able to finish mowing, but definitely don't want to leave it
> like this, so I'll need to find the flaky connection.
>         I can take a picture tonight of where I *think* it is, but want to
> find out if it seems reasonable. There's two relays over on what would be
> the passenger's side of that panel, just behind the speed switch. What do
> those relays control? I'm guessing one is the forward/reverse switch?
>         One of the wires connecting to one of those relays had a wire
> spliced in, that looks like a bad connection waiting to happen (and
> wiggling that wire around, it seems like it was sometimes braking the
> connection there, using my multimeter to measure the resistance on
> opposite ends of that connection). So, I'm guessing that's the source of
> the problem.
>
>         Also, I was not happy with how well the Gator Blades worked. But,
> I'll address that in another email in a minute....
>
> Thanks,
> Mike