Do you have the prints for the job? Are they geared or gearless? Does this happen only on normal? Are you dropping the gate switch, door locks or safety circuit? "UA" for up and "DA" for down are self holding in respect to other relays-you may have a problem with the relay contacts that feed the self holding UA or DA. If it happens in both directions check your "CS" relays-the contacts on all the IBM style relays are prone to issues.

I second E311. Also be very careful around those old IBM relays and if you replace one, I've had the best luck with Yellowjacket replacement relays, the IBM copies you get from Adams are garbage.

I like being able to trace the circuit and with yellows you cannot. If you tape your time and bend points/replace wires/ adjust pick with the screws on you the IBM relays work well. Just slow down and start at the beginning. The worst thing you could do would to just swapping IBM's around. The wires cross up easily and the bases get bent even easier. Also check the push in coil wires.

I've always heard not to use the Yellow Jackets and yes the Adams IBM relays last about 2 weeks if you're lucky...

I love dover composites....off topic but Composites are king

SBRMILTIA...I get up every morning and say a little prayer for you guys. LOL..

Becoming a disappearing breed. One of my best friends, who was a composite ace, just recently passed away. Guys that know that equipment are getting fewer and fewer every day..

Cheers!!!

Here is an old school tip from one of the old school boys that I used to work with. The IBM relays have a plastic piece on the bottom of the coil to the relay. This plastic piece starts out white. Over the years the piece turns yellow and dries out and becomes very brittle. This plastic will then break a peice off due to the relay picking and dropping. When a small piece of the plastic breaks sometime it will fall and keep the relay from picking intermitantly. The best thing to do is to take a small screwdriver or an orange peeling stick and tap all the plastic pieces till you find the ones that are brittle. When you find those they are usually darker than the rest, you break the plastic off of the relay coil altogether. I have never had a problem with these gone, But I have had so many jobs that I have cleaned up just by doing this. Those little pieces that break off can cause such nightmares that I can't even begin to tell you.
I have the composite adjusters manual on pdf if anyone wants it. Just email me and I will try to get it to you. no guarentees but I will try.

Another for those who have good eyesight..

Pull out IBM relay.
Hold relay up to a light and look through the contacts.
You should see daylight through N/O contacts.
Pick relay by hand.
Now you should see daylight through N/C contacts

If Not...Bad contact.

Now when I was young and worked for an independent company, we didn't buy a relay and replace it. My boss would give me pill bottle with 500 needle contacts and I would replace contacts by hand. Pretty easy actually on the 4 pole relays. The 12 pole (Like CS) were a bit more challenging....Needle contacts could be purchased for 10 cents a piece.

lol i had one of those bosses

I have one of those IBM relay testers on the van, so far it has been 100% accurate.

Yep...Those are indeed very cool. 😎

Marbles, Without a print in front of me I dont remember the contact. But you should have a contact that keeps you from seeing your leveling contacts when you take off....... And as far as rebuilding IBM relays between Dover and US equipment I wish I had a buck for each one I have rebuilt. Another trick I learned is the plate on top of the relay can be loosened and adjusted to add x-tra tension to the NC contacts. And will make all kinds of problems go away.

Excellent pointers on how to keep the original style IBMs working. Its amazing how reliable and long lasting the originals have been, (made in the USA)? But going back to my post, I've personally never had to replace a yellow jacket replacement (after ten years on some jobs) or whatever they call the replacements now. Yes, you can't meter the pins, but they do have have the handy coil energized L.E.D. Great thread.

just a question do both elevators do this and do they do this at the same time? are they both at the landing and both take off at the same time then level in? or do the both do it independently?