I recently got an entire used hatch motor assembly. the clear plastic motor housing has a few small hairline cracks in it but it is still intact. Has anybody had any luck putting epoxy or JB Weld on the outside of the housings to prevent them from the cracking the rest of the way?

 

I think Top Down Solutions sells motor assemblies already reinforced with epoxy and aluminum to make them stronger so I seems like it works, at least in theory. What do you have to lose by trying ?

 

I would just get the kit from Lon at TDS. He makes a nice product and one of the few vendors that caters to our relatively small community. I rebuilt my 86 hatch motor with his kit including the reinforced housing and I daily drive my car. No issues at all.

GD

 

I will definetly get one from him if this doesn’t work,but I got another hatch motor and housing so I wanted to see if I could make this work for a while.
May old motor was broken off and laying back there when I removed the panel. The plastic gear also go chewed up.
Many tips for removing the gear and installing the new motor/housing

 

I've tried that. Didn't work. Maybe if I used a stronger adhesive, I don't know - but it came apart almost immediately.

 

You might be able to "Plastic Weld" it using a soldering iron (or gun) and some similar plastic as welding rod. IIRC it is made of Styrene plastic (like the glue it together, model cars). Practice first on junk made of the same plastic.

 

PS Harbor Freight and others, also sell Plastic Welding kits, that I have not tried.

 

 

Thanks. How do I remove the old gear from my original hatch mechanism? It got chewed up but the one in the new used hatch pulldown assembly is good. I just wanted to use the original mechanism that’s already inside my car

 

I’ve noticed several eBay listings for the housings and gears listing them as 86-89...the hatch mechanism
i have to use for parts is from 1988 trans am,will that work on a 1990 Camaro?

 

This was about my experience as well. Took my time let it cure for the suggested time. Fell apart almost instantly.

 

The TDS reinforced housing has some specially formed aluminium reinforcing that is epoxied to the housing....

http://www.top-downsolutions.com/hat...pull-down-unit

For $50 - it's not worth your time to experiment.

GD

 

Once the plastic is cracked, there really isn't much repair to it. If you see the beginnings of stress cracks, you can prolong the inevitable by not abusing the latch. The problem is people slamming the hatch, and ignoring weak hatch strut rods. Don't abuse the pulldown and it'll last virtually forever.

Plastics tend to lose their plasticity over time as moisture and solvents slowly migrate out of the plastic and evaporate. Once that happens, the chances of regaining plasticity are slim. Bonding brittle plastic back to more brittle plastic, usually just shifts the place where it'll crack next time. You could try roughing up the surface for tooth, and applying a slow drying epoxy and a reinforcing media like Fiberglass cloth. A commonly available, SLOW cure epoxy is JBWeld.

The reinforced housing probably isn't a bad idea, but the #1 key is to keep the hatch in good struts, and don't let morons slam the hatch.


There are two pulldown assemblies. 86-91.5 & 91.5-92. The only difference between the 86 and 91 pulldowns are the retainer between the upper/lower halves (one is a bolt/nut, the other is a stud with a push on retainer) and the connectors on the wiring where they plug into the car. A person can change the two wires, or strip the wiring harness out of the pulldown that matches the car, and swap it into the donor pulldown. It's fairly straight forward, just a little time consuming tearing the assemblies down.

 

I replaced my hatch struts as soon as I got the car, and I always set the hatch down gently and let the pull down do the job. I think what did my original 86 motor in is replacing the weatherstripping and the inevitable break-in process and forces involved in compressing the rubber for it to eventually take a "set" and not put up such a fight against the motor. Mine failed and I got the complete deluxe kit from Lon and followed the directions carefully - no problems in several years of daily driving and regularly using my hatch. I agree with Drew that the old plastic is just not worth trying to fix. This is a high stress part and even a new housing wants additional reinforcing. I think it's a lost cause to start with old, brittle, and already failed plastic here.

GD

 

Thanks for the advice guys. The used hatch motor plastic isn’t broken all the way through,it just has small stress cracks starting. You’re probably right General,better just to buy the new housing from TDS and be done with it. I was just thinking since I had this other part laying around that it might last a while. And yes,both my hatch and hood supports are brand new,and I’m always gentle with the hatch. It’s fhe previous owner who broke it.

If its not a whole lot of trouble can you tell me how to replace the plastic gear and housing/motor the easiest way?
Thanks.

 

It's been several years. I followed the instructions in the kit and all went well. I don't remember specifics though. I've only done the one motor so I haven't committed any of it to memory. I don't recall it being particularly difficult.

GD

 

LOOKS LIKE THE BEST SOLUTION!

 

Dorman offers what sure looks to be a glass fiber reinforced plastic housing. Rock Auto sells em cheap. Don't forget to look for a 5% off coupon on the Vendor forum. They also have the new motor/housing replacement assembly unit.






Just a few more options...

 

The only thing you've got to lose in reinforcing the one you have is the effort to redo the whole project over again. Only you can weigh that vs. the cost of the part(s).

 

I took it apart today,and put the used housing on. I didn’t have any instructions and it was extremely easy and straightforward.
the gear was bad on both units I had though so I had to buy one. Dorman makes them. You can get them for $12.99 delivered. I figured since this was so simple to take apart,and the used parts housing was still in good shape with only a couple small hairlines I’d use it for the time being and order a new one from TDS or buy the fiberglass reinforced dorman one.

i got lucky and all the nylon glides in the mechanism are perfect.

does anyone here know what that blue grease is that gm used?