Ideas Please

Dave-R · Post by **Dave-R** » Wed Jul 31, 13 11:38 am

Both "up/down" headlight adjusters are not working on my Corvette.

Searching various forums only results in Yanks saying they are DOOMED and only available from cars being broken for spares.
Unless I want to buy two complete headlight assemblies from GM.

Pulling one of them apart though shows that all that is wrong is that the steel threaded shaft has sized inside this black plastic cog. The threaded shaft has to screw in and out of it.

But I can't free the damn thing. Tried soaking in WD40. I am worried solvents might damage the plastic. I am putting as much weight on twisting it as I dare but if it buggers I am up a dirty creek with nothing to propel myself with.

Any suggestions???

Dave-R · Post by **Dave-R** » Wed Jul 31, 13 11:40 am

I am not patient. I think I am going to try and heat the end of the steel bit unless someone stops me.
Bound to bugger it.

Post by **TyreFryer** » Wed Jul 31, 13 11:45 am

Rather than a flame could you try a hot air gun and maybe on the plastic cog to try and expand it Dave?

Adrian Worman · Post by **Adrian Worman** » Wed Jul 31, 13 12:18 pm

That still may be too much, I would drop the assembly in a kettle of boiling water for a few minutes and try it then

Rebel · Post by **Rebel** » Wed Jul 31, 13 12:36 pm

Does the cog have any movement at all?

Maybe turn it back and forth continuously if there is any movement, to see if it frees up at all, the threads might just be blocked with crud

Could the cog be replaced with something else if you do break it?

charger01 · Post by **charger01** » Wed Jul 31, 13 12:44 pm

Use a hairdryer on the plastic to expand it Dave. You must have one in the boot with the carmen rollers & scissors

db · Post by db » Wed Jul 31, 13 12:45 pm

I'm with Ade W, boil the bugger, might clear out some crud too.
It may be the threads are chewed though and that's why it's jammed

Dave-R · Post by **Dave-R** » Wed Jul 31, 13 12:46 pm

Got it!!

Took some effort though. That plastic cog is moulded around a steel nut. THAT is why it was corroded solid. It just took a long time of soaking to get the WD40 down inside deep enough.

No sign of any kind of lubricant/grease in this thing.

Once I got a slight movement I could work it in and out until it came off. Lots of rust inside.

I am going to clean up all the threads and pack this thing with white grease.

Then I have the other side to do once it is back on.

Think it's time for a bit of lunch 'cos I am bloody starvin' now.

I knew it must be fixable somehow though. Bloody Corvette owners know nowt.

autofetish · Post by **autofetish** » Wed Jul 31, 13 12:49 pm

car battery

connect - to one end

and tap other end a few times with the +

Dave-R · Post by **Dave-R** » Wed Jul 31, 13 12:57 pm

autofetish wrote:car battery

connect - to one end

and tap other end a few times with the +

That is how to weld mate.

Dave-R · Post by **Dave-R** » Wed Jul 31, 13 3:34 pm

Both done now.

Just waiting for less sun so I can line the headlights up.

That second one was hard to free off as well. Took me a couple of hours of soaking and some considerable effort.