Author Topic: Pulling the Gib-Keys on a GM90 6/1 listeroid.  (Read 3039 times)


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Pulling the Gib-Keys on a GM90 6/1 listeroid.
« on: May 24, 2009, 09:07:46 PM »

A fellow mechanic bud gave me a hand this weekend pulling the keys.  Took a little less than 2 hours, we were being cautious not to break the key head off in place.

Tools/ supplies: patience, ball peen hammer, vixen file, assorted crescent wrenches, Kroil (penetrating oil), rags, Gib-Key puller from Central Maine Diesel. (see posting in market place)

The engines gib-key heads were deformed from installation in India and prior to slipping the puller over the keys, we had to file the key heads and sides to allow the puller to fit.  We also filed the back face of the key to give the puller a good flat grip.

We had issues with the puller cocking out opposite the key. 
When tightening the bolts nearest the key (starts pulling the plate and hopefully the key back), the opposite end of the plate would come forward cocking the plate at a angle and jamming it on the crank.  We almost went looking for a large c-clamp to force that end back or keep it in place.

Two things helped:
One person using a ball peen hammer on the cocked out side of the puller plate opposite the key area acted as a lever and started the key moving out.  Person #2 keeps the proper tightness on the bolts nearest the key while #1 is using the hammer.

The other was once the keys were moving; we installed the bolts backwards so the bolt heads rested on the flywheel pushing the puller plate instead of pulling.  This helped keep the plate square.

The keys are so soft the heads deform when being removed. 
In a pinch you could file the key back to shape and reuse it but new keys are so reasonable that I wouldn’t take the chance of having a head get pulled off on its second removal.

Bottom line we had a great morning improvising and problem solving.
6/1 GM90 disassembled and in work

5KW ST sold
Northern Lights 7KW sold