87bluebird

i have an 87 Pontiac firebird base coupe and there is an electric motor that raises and lowers the rear hatch to shut it tight. last weekend i opened the hatch and the latch didnt raise back up. so now i cant latch my hatch and it flops up and down. how do i fix this. i know there is power back there because the light comes on.

1988GTA500HP

The light on my 88 is powered by an orange wire, and the hatch pulldown is powered by a separate red/white wire. I don't know if this is stock or not since I just recently bought the car. I would start by verifying you have power to the pulldown with a meter or test light. Also, there is a little plastic sensor switch in front of where the hatch catches the latching mechanism. Using a screwdriver or something, I just use my finger, depress the switch to see if the motor turns on. If so, let it run until it bottoms out (you should hear a click). Then when you remove your finger it should raise again. When it is depressed, it thinks the trunk is closed and lowers the pulldown. When it is not depressed, it thinks the hatch is open and raises the pulldown. Maybe it stopped in the middle of the cycle.

87bluebird

a you talking about the petal plate on top of the rear interior panel that connects with the switch on the hatch when it closes and it stuck at the bottom of the cycle didn't raise at all. is there any way of taking it apart and maybe turning it by hand to at least get it to latch

1988GTA500HP

No. That connection is for your third brake light. If you look at the catch that is on the hatch itself and slowly close the hatch you will see where the hatch latches to the mechanism on the bottom which is behind the plastic panel in your cargo area. Then raise the hatch and look down on the mechanism and you will see a small black plastic switch between the metal latching mechanism and the rear of the car. Depress that switch and see if the motor makes any sound. If not you need to troubleshoot what the problem is, and I would start with VERIFYING that I am getting power to the unit.

My hatch pulldown didn't work when I got the car and the previous owner had just loosened the bolts and slid the entire latching mechanism to a height where he could just slam the hatch and it would catch. I don't recommend this as slamming the hatch can cause all kinds of damage to the pulldown mechanism. I just went to the junkyard and pulled a hatch pulldown motor out of a 73 Cadillac and swapped it with mine. The motors were used by all GM cars from 77 to 91 I believe. I pulled one from a 93 and it was an exact match so I bought it and it works fine.

87bluebird

i tried that switch on the latch and nothing happened if it ain't raining hard tomorrow ill try jumping power from the lite directly to the motor and see if that works.

1988GTA500HP

That sounds like a good idea. Lonsal is the master when it comes to the hatch pulldown He is a moderator here and owner of Top Down Solutions. Here is a link to a repair guide which he wrote.

https://www.thirdgen.org/tech/hatchpulldown.pdf

DJP87Z28

Did you stick your finger between the brushes and find the switch at the bottom of the pull down. I don't think you understand this concept yet?

Nothing is going to grab your finger.....

87bluebird

i know what switch your talking about. nothing happens i tried jumping power from the light to the motor and nothing hapend. so im thinking the electric motor is shot. ill try and get a new one in a couple of weeks. first i gotta finish fighting the exhaust manifold

1988GTA500HP

When you say you jumped power directly to the motor from the light, do you mean you put power to the blue wire or did you disassemble the mechanism and put power directly to the motor? If you just put power to the blue wire, that doesn't mean that the motor is def shot. There are other parts that it could be (reverse switch, relay, etc.). The only way to be positive it's the motor is to remove the motor and housing and apply power and ground to the motor tabs. The motor is reversible so it does not matter which tang you apply power to and which tang you apply ground to.

lonsal

iTrader: (2)

I've had some customers swear they are pressing on the striker-sensing switch and instead were pressing on the top of the rod that holds the spring for the little nylon piece that centers the hatch hook. The actual switch part of the striker-sensing switch is a small paddle sticking out of the plastic body. The body of the switch is attached to the latch assy by a single hex-head screw. There are wires coming out of it, orange, black & white.

Lon

87bluebird

i disassembled the latch assembly and puled the black box out which i think is the reversing switch then i put the wire ends from the light directly to the copper tabs.and nothing happened. iv been wrestling the exhaust manifold all week when im done with that i'll go to this.ill raise it up enough to slam it shut for now. and eventually replace it.

87bluebird

does anyone have one of these there willing to sell for a low price.

evilemokid94

iTrader: (6)

can you post pictures of this please?

87bluebird

i finally got back to playing with this part. i raised it manually so that i could slam it shut. but my hatch was really miss aligned and the hook on the hatch would not go in the latch. witch is strange cuz it shut fine a month ago before the latch stopped working. the hatch stuck a good inch past the rear fenders so i shoved it as far forward as i could. its still a good 1/4 to 3/8 of an inch past it. and the hook still wouldn't go into latch. then i realized the hook leans toward the back of the car. so i figured i could spin it around so it leaned toward the front of the car. but for some reason one of the bolts wouldn't line up. so tomorrow i'll put it in the drill press and expand that bolt hole. do they all lean back like that or is mine bent?

evilemokid94 i don't have a cam so i cant get you a pick but somebody else mite or you can and you mite get lucky and find a pick

lonsal

iTrader: (2)

Don't modify the hatch hook to make it fit the latch. Instead follow the Tech Article that another fellow thirdgenner created:

https://www.thirdgen.org/hatchalign

87bluebird

that sounds really dangerous and probably beyond my ability's i loosened the bolts that connect the hatch to the glass and shoved it forward as far as it would go.that helped with the alignment. but what that guy talks about say's
"*** CAUTION *** HAZARDOUS STEP" way to many times. giving the way my lucks been going lately i would probably end up with a broken rear hatch glass. and i would rather buy a new hatch hook than a new rear window

lonsal

iTrader: (2)

OK, so you'll fix it by applying a bandaid fix rather than correctly fixing the problem. If you're not up to doing the repair you can always take the car to a body shop and have them do it properly. With your fix, yes it might work, but the spoiler will still stick out too far and look bad. It all boils down to whether you want to fix the actual problem or cure the symptom of the problem.

Lon

87bluebird

i do want to correctly fix the problem. but i just put all my money into engine and steering trying to get the car ready to go on the road. the bandaid is just temporary till i get the money to have it done rite. i was just wondering if it would work

evilemokid94

iTrader: (6)

my hatch is the same way, and i thought about doing the same thing but idk, id like to see where this goes before i make my final choice

lonsal

iTrader: (2)

I can't answer since I haven't used that bandaid myself. There are two areas that can cause the spoiler portion of the hatch to be too far to the rear. The hatch hinge bolts or the metal portion rear of the glass. Remember to prop up the hatch and remove the hatch struts when doing the adjustment. It is the pressure of the gas struts that forces it to the rear if there is any looseness.

Lon

copyfixr

iTrader: (3)

I had a similar problem. Do yourself a favor, and order a set of sliders and a gear nut from TDS. Take it all apart, clean and lube it and put in the new parts and it will work like new. The sliders and gear nut are cheap and a tube of white lithium grease for a couple bucks.

lonsal

iTrader: (2)

I no longer sell the tubes of white lithium grease due to a problem with my supplier. Instead I sell packets of blue synthetic grease.

Lon

evilemokid94

iTrader: (6)

iv lossened the bolts at the top of the hatch, and iv taken off my hatch struts, now what?

87bluebird

what i did was just shove it forward as far as it would go and tightened the bolts back down. my still sticks out a 1/4 of an inch but that's a lot better than it was.
my hatch hook still wouldn't line up with the hatch tho
that's why i thought to do the "bandaid" of spinning the hook around. i just did that a few minutes ago and it worked im finally able to lock my hatch again. in a couple of months when i get some more money i'll get the hatch realigned then i'll start looking thru the junk yards for a new latch and hook. but at least i can slam it shut for now.

evilemokid94

iTrader: (6)

see i did that, and i also had the same idea, anyways so it works? what size drill bit did you use to enlarge the holes?, and can you take pictures of how this looks?

87bluebird

im not sure what size bit it was it was already in the drill press. it was just slightly larger than the stock bolt holes. i took the hook off and spun it around and figured out which hole was stopping me and drilled that one out and then just stretched it out till it would slide on the bolts easy. then just bolted it up and slammed the hatch shut. i know it not a proper fix but its just temporary till i get the money to do it rite.

evilemokid94

iTrader: (6)

do you have any pictures of how the striker looks?

artmanc

I'm glad I looked at this post and happy to see a link to "Top-Down Solutions" for the Nylon Guides and Gear nut.

This was not the first post I found and in my haste to get the assembly apart and diagnosed I failed to do a few things that "Lonsal" high lighted in red such as "not taking cover off motor" and marking position of mounting bracket that motor travels on.

So as soon as I get the Guides and gear nut my plan is to 1. Put cover back on motor with care to the brushes and 2. Loosely bolt bracket and motor assembly to body, activate the motor long enough to reach its down position and then unplug harness for safety. 3. I'm thinking at this point I should be able to pull motor and bracket up to the latch and tighten bolts leaving everything in a funtional position, am I wrong?

88KyKITT

BUMP

I am having issues with min, Just bought the car, Replaced the pull down motor, And the relay. The Red/White wire is hot. The latch is in the raised position, i cannot get it to respond, depressing the little spring loaded paddle switch does nothing...not certain what to check, or how to resolve. Please assist.

lonsal

iTrader: (2)

Call me and I'll give yo instructions on how to test your reversing switch. Either the striker-sensing switch or the reversing switch can cause the problem you describe.

Lon Salgren
626-369-0040

88KyKITT

Thank you Lon. After you call...Found the issue, Burnt contact in the reversing switch. Now, i am in a pickle, Adjusted the "overbite" after i repaired the pulldown, only to remember i have no key. The Button on the dash doesnt pop the hatch....

lonsal

iTrader: (2)

Did you remember to install the ground wire that goes from the 10mm screw (that mounts the hatch release solenoid) to the body ground location below the pull-down unit? If that ground wire is not present the solenoid will not fire because it is electrically isolated from ground by the guides.

Next try engaging the parking brake and try the hatch release switch again.

If you did not install the rear hatch surround trim panel you can crawl thru and remove the solenoid. You will see a square shaped hole on the left side of the latch. Move the lever inside to the left to release the latch.

Lon

horsecrazychick

Lon -

I may have to call you as well and get the directions on testing the reversing switch. My son slammed the trunk lid awhile back. I replaced the pull down motor and a blown fuse. It didn't do anything, then a week later in the middle of the night it actuated and pulled the lid down (possessed!). We pushed the button inside and the trunk raised, wouldn't let go of the latch and powered back down. Then used the key and it raised and won't do anything again.

Hawkeye1980

iTrader: (3)

Hi Lon and all

Well I got it working finally. Thanks for all the help!! now I have a new problem unrelated.....never ends

Hawkeye1980

iTrader: (3)

Not so soon. now the pull down rails are hanging up when I close the back window. It pulls down so far then starts a grinding noise.

I am using new plastic guides for the mechanism. But they seem to get hung up. I remember the original stock ones would be loose enough that if you removed the motor, the mechanism would slowly slide down and fall out. I had to support the mechanism while servicing the motor.

So..I have 2 issues, one the new plastic rails although fit fine must be too tight and are hanging up. So how to resolve:
1. What grease should I use for the plastic rails? (currently using white lithium grease)
2. should I sand down the plastic rails to make then less tight?? (I read somewhere I should)

lonsal

iTrader: (2)

Yes sand the guides until the latch portion slides easily.. start with installing either the outer 2 or inner 2 only. No grease on the track. Manually slide the latch portion up and down 10x. Then disassemble. Inspect the guides. Sand off any dark lines (which indicate the contact point). Continue doing this until ther is no more dark lines formed and it slides easily. Now install just the other 2 and do the same. Once you have all 4 sanded and sliding easily then assemble with grease. White lithium grease is fine, having roughly the same buttery consistency as the original grease. I use and supply synthetic marine grease instead with my kits because it tends to not dry out as quickly.

Lon Salgren
Top-Down Solutions

Hawkeye1980

iTrader: (3)

Lon

Thank you SO MUCH! I see on your site you have the marine grease. I will be ordering very soon!

Hawkeye1980

iTrader: (3)

Ok so I took this whole thing apart...AGAIN for the 20th time. I sanded down the plastic rails and got mechanism to slide cleanly even before the grease. There is an upper switch next to the catch lock for the metal loop on the trunk lid. That switch is wired to the motor and when depressed, the whole unit pulls the trunk lid down, when released the trunk whole unit rises up. That is working perfectly.

However...
When I actually lower the trunk lid, it pulls down then stops and grinds. the toggle switch does not travel far down enough to flip it up and cause the motor to shut off. if I unlock it with the key the motor shuts off, but, I have to press the upper switch next to the catch lock so it will travel down just enough to trip the toggle switch up and stopping the motor.

Now mind you this WAS working, not very long, perfectly. The issue I believed was as stated, the plastic rails were to tight and they were getting hung up. By sanding them down it would free them from binding up, which it did and I thought would fix the issue. Although this needed to be done, it did not fix the original issue.

For some odd reason, the deck cannot be pulled down enough by the motor so as to stop the motor from running. About 3/8" or so more travel is needed, maybe less. I am at a loss, this is unbelievable.

The only fix I see is somehow bending the metal tab at the lower end up so the toggle switch is tripped sooner, hence, shutting off the motor.

Any ideas otherwise? This is very frustrating.

Hawkeye1980

iTrader: (3)

Never mind. I must have a mental block haha. So I thought, I need to get the loop on the trunk lid to drop down...AHH washers! As I started putting them in, I looked at the WHOLE unit, not just were the plastic slides are. 3 bolts hold the entire unit to the body of the car. DOPE I AM. its ADJUSTABLE! Of course, and the entire unit was pushed all the way down. I bought it all the up, tightened the 3 larges bolts... FIXED.

Dumb@$$ I am. Thanks everyone again!