Re: A little something I've been working on....
 

Iggy - how about not needing ANY relays???? JiimG found this - in my case this is all I need to stop down travel! Only about $20 and bolt-on!!

Yea JimG!!

See safety collars. Simple, probably very effective. Just rachets when it hits the collar.

http://www.rexmar.com/page52.html

Re: A little something I've been working on....
 

To Iggy;
Thanks for the clarification.
Case not grounded, huh. Must be so.

Re: A little something I've been working on....
 

keep it up guys ....bet that motor will be alot happier with full Voltage ...I wonder if redoing the Hatch ...ie foam and plywood would lighten it up ? I read where there is a new backing material thats lighter and water proof ...and the newer foams are lighter ....

Re: A little something I've been working on....
 

All of the hatch lifts have a built in clutch that ratchets when it reaches it's limit of travel. Problem is that as the mechanism ages it tends to hang up and stick at either extreme. The only way to free it is to disassemble the mechanism. I've had mine apart several times and greased everything in sight, but it still hangs up.
I know, the easy answer is to replace it. But that's not really the answer because this problem will reappear somewhere down the road.
You see i'm kind of cheap. If I can make this work for about 150.00 it'll save me the cost of a new screw lift which is more than double the cost of my idea. And, it'll last as long as the electric drive motor does.

mcollinstn, you claim it can be done with only two relays.......show me. I'm open to all suggestions.

Keep the ideas comming. I like it.

Re: A little something I've been working on....
 

Heres a quickie:
Marine solenoid (trim style is fine $12) acts as on/off for the high current power.
DPDT solenoid (30A automotive style or potted marine flavor) acts as reverser.
Limit switches (25A) break current on extreme travel.
This setup is drawn to use standard Formula polarity reversing wiring harness with no changes at the dash. One polarity energizes the solenoid, but sends additional NEG to relay coil, leaving it DeEnergized. Other polarity still energizes solenoid (since it doesnt care which polarity it gets) AND also sends 12v+ to relay coil, which energizes it for direction change.

I can whip up another one that allows low current limit switches (cheaper and smaller) but it will require pulling 4 additional runs of wire from the dash switch (same theory in that you break the crossovers at the DPDT dash switch)..

mc

Re: A little something I've been working on....
 

I like Wally's way, but you don't currently have the dash wiring set up like that.
Wouldn't be hard to do though, and you could break the low current ground wires thru little microswitches easily.

Re: A little something I've been working on....
 

mcollinstn, your right the dash isnt set up that way now......but here's the beauty of it....you allready have two wires running back from the switch to the hatch motor....only thing is that the switch reverses the polarity by a set of jumpers that criss cross each other.......all you need to do is remove the jumpers and take the 12v supply off the switch and swap it with a ground......wouldnt take more then 15min total if you had to unscrew the dash to get at the back of the switch!!! Then all you woudl need to do is find the wires in the engine compt and add your relays and micro switches.

I did this setup for a friends hatch lift (minus the micro switches) all in about 30 min. I had the relays pre-wired and all i had to do was crimp and heat shrink the leads to the motor and relays :D

Re: A little something I've been working on....
 

Keep the hatch shut, problem solved!

Re: A little something I've been working on....
 

McCollistn or anyone-???
What is a source for the prewired socket for the Bosch relays?? It makes for a nicer, cleaner install. Thanks

Re: A little something I've been working on....
 

http://cgi.ebay.com/ws/eBayISAPI.dll...857287070&rd=1

Courtesy of the "World's Marketplace".