Distributor rotor removal problem

andyd

One of the torx screws holding on the rotor has rusted to the point I cannot turn it. Has anyone had experience with drilling out the screw and tapping a new thread? Long shot, but I thought I'd ask before jumping in.

Andy

aero3113

Is there enough room to use a Dremel to cut a slot for a flathead screwdriver?

andyd

The screw is tiny, T2 size I think, plus it's recessed into the rotor body. Also, it is really crumbly and rusty, so cutting a slot isn't possible. Thanks for the suggestion though.

Andy

andyd

Rotor is an ACDelco D465.

Andy

aero3113

Do you have any valve grinding compound? Put a little on the tip of the screw driver. If there’s still enough material it will help grip the screw and remove it. You can also try drilling the head off and when you remove the rotor hopefully there’s enough of the screw to use a pair of vice grips to unscrew it.

andyd

I quit for the day, I'll be back to it tomorrow and try what you suggest. Why one screw rusted so badly and the other didn't is odd. 5 years since last replaced. What a pain!

Andy

Aqua_Aura

If all else fails couldn't you crack the rotor housing and then expose the screw completely to maybe grab it with some vice grips. I assume you are replacing the cap anyway. 

aero3113

@Aqua_Aura that’s a good idea also. I would try that before drilling the head off. Maybe use a Dremel to remove the material to access the screw head.

Ian

Have you drowned it in WD40?

69fastback

Get some of this to soak it in. 

https://pilotshq.com/products/kano-aerokroil-penetrating-oil-10oz-aerosol?variant=32643585966216&utm_medium=cpc&utm_source=google&utm_campaign=Google%20Shopping&gclid=EAIaIQobChMI7KGShM6A7AIVAtvACh1lsQI2EAQYASABEgJzXfD_BwE

Aqua_Aura

That's some good stuff. 

aero3113

Aqua_Aura said:

That's some good stuff. 

Yes
For penetrating oil, I like Aerokroil the best.

andyd

Thanks for the tips. I did soak it in WD-40. The head of the screw is about 50% rusted away, I think if I can drill the top off the screw, remove the rotor, there might be enough good steel in the shaft to allow it to be gripped and turned. Cutting away the plastic might work, but it would put plastic debris into the distributor. In the end the distributor may have to come out to make access easy rather than working on it in situ. Andy

69fastback

Have you tried tighteneing the screw and then loosening it?sometimes they just need broken loose. 

mcmars

best penetrating fluid I have used is 50/50 mix of dexron tranny fluid and acetone.  Soak it over night.  Find best fitting torx tool you have and ever so gently, but firmly, tap the torx down a few times with tiny hammer as you apply rotational counter clockwise force to simulate an impact tool.  If that fails and torx starts to strips out or slip, I would grind 2 flats on either side of screw head and use small needle nose channel locks.

andyd

There is nothing left of the "star" that would provide any grip to the Torx bit. Andy

raybo3

Try a left handed drill bit. They work great

reneechris14

raybo3 said:

Try a left handed drill bit. They work great

This worked for me.

69fastback

raybo3 said:

Try a left handed drill bit. They work great

Yes, if you’re down to drilling it out, a left handed drill bit works better than any extractor kit. You can buy a whole set of left handed drill bits at harbor freight for $8. I always keep a set. 

andyd

I just happen to be passing by Harbor Freight in Oceanside this morning and I'll pick up some of those LH bits. Thanks guys! Andy

reneechris14

You know how a drill bit grabs just when ready to punch through, sometimes a bit will grab and back the srcew out, but you know that.

andyd

Harbor Freight was sold out of only one type of drill set...yep the LH one. Got on Amazon in their parking lot and ordered a set, arrives tomorrow. Andy

andyd

I love it when a plan comes together. Yep, reverse drill bit did the trick. Thanks for the suggestions. Andy

andyd

Special shout out to @raybo3 for the first mention of LH drill bits! Andy.

aero3113

Nice!

raybo3

@andyd glad it worked out good for you. 

Handymans342

andyd said:

Special shout out to @raybo3 for the first mention of LH drill bits! Andy.

He uses those a lot on the China Bomb trains. LOL

TonyG13

I've used extractor bits, but until today I've never heard of left-handed drill bits. I thought that would be something Ned Flanders would sell at his Leftorium.

But seriously, what would be the need or usage for a left handed bit (other than extraction)?  

andyd

@TonyG13 I can't think of another purpose for LH drill bit, but I can understand why they are popular by the ocean! Rust never sleeps. Andy

LaRea

Note the copious application of thread lock on that screw ...

Spyderweb

Never heard of LH bits.  Great trick!