Month: May 2017

Barbarossa Backstay Adjuster Repair

The wheel has not been repaired yet and Matilda is still hanging in the travel lift. This is not only very disappointing but I am dangerously running out of time now.

Anyway, whist waiting I decided that I should do something to turn the bad experience into a good one. The back stay tensioner had probably never been opened before and was not providing that feeling of a reliably working device anymore. Operation was a bit tight and it was on my to-do list for a longer time.

The device is made by the Italian company Barbarossa and there was no information at all on the web as the company does not exist anymore.  When I opened it I found a seized axial bearing and a bearing washer which was dissolved in pieces. I searched the internet and found that I could replace it by SKF’s AXK2542. I decided not to remove it before I have the new one in hand. Next day, with the replacement needle roller bearing in hand, I tried to remove the old one carefully. It wouldn’t come off easily but after applying some heat and force the job was finally accomplished. Underneath the axial bearing, there was another radial bearing which wasn’t looking much better. The point of no return was reached. I had to find replacement bearings in order to get Matilda in the water when the wheel for the travel lift would finally arrive.

Amazing that the backstay tensioner was still working

With some effort, the old bearings were finally removed

To keep a long story short, these are the parts that I used to replace the old bearings and they fit quite well:

Radial bearing: SKF RNA4904 (inner ring removed)
Axial bearing: SKF AXK2542, GS81105 and AS2542 (two times).
The axial bearing needs to have a total thickness of 7mm.

The new parts are available from SKF

I heated up the housing for the radial bearing to 200°C and put the RNA4904 into the deep fridge for an hour. When I put it in, it slid down to the bottom without any force applied.

I generously applied high pressure grease and closed everything. It works again like new.