Hullavator Alert

My wife and I are are taking a 5 hour trip next week up to Lake James in North Carolina with our kayaks so this morning I thought I’d give the car a good check over.

We haven’t been kayaking for the last couple of weeks for various reasons but the Hullavators have been on the car. When I checked them this morning one of the front top cradle assemblies was very loose and wobbly. Now my Hullavators are over 7 years old and I don’t know if the latest models are built the same way but what I discovered was that one of the cap screws that holds the cradle assembly to the slide plate was quite loose and the other was completely loose. Fortunately, the screw hadn’t disappeared and with a 5mm hex/Allen key it was easy to put the socket head cap screw back in and tighten things up.

So of course I checked all the others. None of them were actually loose but several were not snugged up as much as I’d liked. In future when I service the Hullavators I’ll be sure to check all these screws.

Here’s a photo with arrows pointing to the screws just in case my description wasn’t clear…

Thanks! My cradles are up right now, will go take a look.

OK l did. Three are rock tight, the fourth is not an immediate issue but has a small bit of rocking available. When l and my hex set find each other that will be tightened.

Thanks for the heads up. Makes me somewhat glad for the second strap l add for longer trips too.

Mine are inside right now so I checked. No play in any of them. A deeper inspection will have to wait as I have 1/4" of neoprene covering the pads where the screws are. Not glued, but attached with double sided tape. Need more tape.

Good tip. Thanks.

I don’t have Hullivators but we have had various feet on rack systems loosen up. It is a good reminder to check everything on your rack system that has a screw. Most likely your rack system came with an Allen Wrench… Mark it well and stow it in a place that makes sense labeled as to what it is for. When you have something loose it is a bad time to have to hunt for the right size Allen wrench.

That’s a good tip.

I have a garage full of tools - probably 4 or 5 sets of both metric and SAE Allen keys in various lengths - but the Thule Hullavators use M6 cap screws that use a 5mm hex key just about exclusively for all their fittings so I keep a short 5mm key in my car’s glovebox just in case I need one at a launch or on the road.

As to general maintenance, l and with Jim before went beyond tightening down screws on parts like foot packs or towers. When keeping things tight started involving too frequent screw tightening, we replaced the part. Over time a tendency to loosen up can point to a bigger problem.

Never had a rack failure or even close.

The screws in the picture here are ones that should require almost no maintenance, but obviously more than never.

I guess what threw me is that those screws are both not obvious (they sit deep in a little well) and that they are put there by the factory. Right next to them are the rivets that connect the metal tubes but I guess they couldn’t have use rivets here as you wouldn’t want rivet heads protruding from the other side of the slide plate.

I’m also a maintenance nut and I think what I’ll do is to add a SS lock washer to each of those cap screws. Either that or I’ll put some threadlocker on them. Or both!


I agree those are not screws that would jump out as needing attention, compared to the rest of the assembly.

Report back on how it goes trying to add a SS lock washer? I don’t have enough loose to need to do more than tighten down one of the four. But if it seems worth it to get them all out to add something like that… or at least add it to the one that seems to be the only current offender.

I looked through my box of stainless stuff but the lock washers I have were too small or too big so I thought I’d use some blue (medium) threadlocker on all 16 of the cap screws (2 Hullavators).

Looking at the screws closely I think the factory did put them in using threadlocker but mine are over 7 years old and have been subjected to lots of travel and big temperature differences, and lots of salt water.

The top/inner/moveable cradle is easy. The slide plate is fairly long and has three threaded holes in it; two for the retaining cap screws and one for the three-wing knob. That knob holds everything in place so you can just take out the two cap screws, put a little threadlocker on them, put the screws back and snug them up. The screws do have a small washer on them but it’s not a lock washer.

The bottom/fixed/outer cradle is a little trickier. If you try to do it with the arm in a vertical position you’ll find that the cap screws are secured to M6 sliding square nuts that fit into the slot and when you remove the cap screws these nuts will fall to the floor and roll underneath your car to a point where it’s difficult to reach them on a sweltering 94 degree afternoon where everything is too hot to touch. Don’t ask me how I know.

So, the best way to do these is with the arm in a horizontal position. It’s still a little fiddly lining up the nuts to accept the cap screws you’ve just treated with threadlocker, but it’s really not that difficult.

Everything seems to be very secure now but if I do find I have a “repeat offender” I’ll go buy some of the correct sized lock washers.

Oh, and I don’t know why you’d want to do this but that outer cradle will actually slide in the arm slot if you loosen both cap screws. Of course I think you just really need the inner “adjustable” arm to move with its easy to use wing knob.

There is a decent diagram of all the Hullavator parts at

'Hope this helps.

Thanks. I am not sure where I put the instructions now for any of it, I usually figure I can always download them from online if needed. But I always prefer taking stuff apart as a way to see how it got put together. So the extra help from your work is going to make it easier.