Whitlock Cobra IIE+ noises

[thostr]

I've got a 1983 Scanmar 33 sailboat which seems to be fitted with a very old version of the Whitlock Cobra steering system, the II E+. Recently it's developed an issue. When there is rudder pressure when tacking up against the wind from port side, I can hear a popping sound and feel some stiffness at a single certain point when going up against the wind. Other than that, the rudder works perfectly. There is very little play (when filming the tiller arm from underneath when moving the wheel I), and unless there is rudder pressure, no popping sound will occur. I've talked to other Scanmar owners that have had similar issues, and they've managed to rectify by tightening the bolts on top of the quadrant. On my Cobra, there is no nut on top, just a cover and a circlip.

Any suggestions as to what is going on here and how to fix it?

 

[Gazza]

Hi,

Can't help you with a diagnosis, but I think I know someone who can. Try whitlocksteering.com or yachtsteeringservices - they seem to be moving over to a new website. Cliff Mogridge is an ex Lewmar employee who specialises in Whitlock systems - he repaired and refurbished the top bearings and friction screw on our system for a reasonable cost.

Hope that helps.

 

[thostr]

Thanks Gazza. I've sent them a request.

Did inspect the rack and pinion system today using a endoscope, could see absolutely no wear pinion and almost no wear on rack quadrant. Absolutely no play on wheel nor sideways on shaft. This version of the Cobra has no way of reshimming or tightening the gears other than making sure the top plate sits firmly on top of the shaft cap, preventing the quadrant from moving up. Turned out two of the screws closest to the pinion were finger loose almost, possibly because of my choice of anti seizing compound (copper compound). Hope tightening these will help. Will change to Loctite on these. Also seems it may be possible to put a shim on top of the shaft cap to increase downward force on the quadrant, but I'll wait with that and see if tightening the top place cuts it... *fingers crossed*

 

[Cardinal]

Please keep us posted as to how you get on.

 

[thostr]

Update: noises seem to have disappeared and rudder function is smooth, after I removed and sanded top plate so it would fit perfectly on the pidestal. Not being aware of its function of keeping down the rudder shaft inside the pedestal, I had inadvertently shimmed the top cover when adding guard rails and refinishing pedestal last year (paint and sealant).

Yesterdays sailing featured nice wind and I tested with lots of rudder pressure without hearing anything unnormal: https://vimeo.com/291336839?activityReferer=1

 

[PaulR]

how did you refinish the pedestal? ours is also a cobra (and serviced before by Cliff - excellent) but some of the white coating is peeling off exposing alloy beneath - on job list this winter to recoat so be very glad of recommendation as to how best to do it please

 

[thostr]

My finish is holding up well, albeit the finish could be better

I first sanded the pedestal lightly and with a focus on areas that had chips and paint coming off, then used two component products from Hempel Yachting. First their epoxy primer ('High protect') and then a two component polyurethane paint. If and when I'm going to redo it (not likely) I'll be more careful with paint thickness. These are fairly heavy primers and paints, and I managed to get some sag which probably easily could be avoided by both using some thinner in the paint as well as being a bit more careful. As the above thread indicates, I actually managed to build up so much paint that the top cover did not fit well on the pidestal! Oh well, it's all learning.

Guess any epoxy primer and polyurethane paint will do. I consulted the local paint shop, and it sounded like this was an obvious choice for a aluminium object like the Cobra. YMMV.