700 Removing Thrust Bearings From Trex 700e Head

[Harford]

I am starting the process of assembling my Trex 700E FBL. I want to check that the thrust bearings are correctly assembled and greased. How can I remove them (and the radial bearing) from the blade grip please without damaging anything. They appear to be a very tight fit.
I have read that placing the blade grip in the oven for a period (eg. 15min at 250F) is a solution.

I would very much appreciate some advice on this.

Thank you

 

[Tony]

Most likely, they finally got smart and have an interference fit of a half thou or so. In which case, you can slightly heat up the grip and they should fall out. If they don't, you may need to press them out. But definitely look into if they are greased well!

 

[Harford]

Thank you Tony. So 15 mins at 250 F sounds too much ?

 

[Tony]

I was just thinking a hair dryer. You don't want to heat it up so much that you discolor the anodizing. Which can happen at a temp as low as 250ºF.

 

[Harford]

Prior to your advice about the hair dryer, I tried approx 5 mins at 250F in the oven. No movement at all. Are there any alternatives. Align manual says inspect the thrust bearings every 20 flights so you would hope they at least have a workable procedure to allow this to happen.
Thanks again
Michael

 

[Tony]

Might need to press then out.

 

[Harford]

I was afraid you were going to say that (but I guess it is the only alternative). From which end do you press please - I am nervous about destroying the bearings, among other things !

 

[Tony]

There should be two radial bearings. One on the outside and one on the inside. Also on the inside is the thrust bearing. So it depends on what radial bearing you are trying to get out as to which way you need to press. If inside, press from outside to in. For outside, press inside to out.

 

[Harford]

Well I understand that logic. I am trying to get to the thrust bearing which is between the two radial bearings. My concern was that the radial bearing next to the damper may be sitting against a lip of some sort. I don't say this from experience because the head was assembled when I got it but the diagram in the manual seems to show some sort of lip. I could be completely wrong, hence my question.

 

[Tony]

No worries. There is a lip in there that keeps distance between the inside bearing (against the damper) and the outside thrust bearing or radial bearing (inside the grip. Some install them backwards).

 

[Smoggie]

They are not a very tight fit. If you use a drift (any steel rod a bit smaller than the feathering shaft) and go in through the inboard bearing you should be able to catch the inner edge of the outer bearing. It should tap out with minimum effort.
If the builder used bearing retainer then it will need more force, a press may then be required.

 

[Harford]

Thank you both for this. I will try these options and report back
Michael