Fixpoints - Corrosion Of The Aluminium Fouling The Threads

[Grogey]

Hi

I've bought a set of Toyota accessory roof bars and have found them a neat simple set up. However when i tried bolting them on, the first bolt quickly became very stiff to turn and it became apparent that the aluminium block which forms the fixpoint had enough corrosion to foul the internal threads. They are all the same. Very Frustrating. I've backed off installing them for now as I didn't want to damage the threads forcing things.

The Toyota Dealer said look elsewhere when i called them about this issue. They said i should tap them out, but they wouldn't do it as it wasn't strictly a mechanical issue and not something there technicians can do. All very interesting given the 5 Year warranty I still have over a year left on, but I'm not a the point, yet, where I'm going to start a warranty fight over tapping 4 internal threads. But I still think they are blowing me off. They said these fixpoints are not replacable parts which doesn't bode well if replacement became necessary.

I think i just need to get the threads cleaned out.

Anyone else experience this issue. Any tips on removing the white powdery corrosion.

Phosphoric acid dissolves this corrosion but not the metal if i can get some. I've never used it though.

Cheers.

[weeleyboy]

When you have cleaned the threads out I suggest you use some copper grease which I find controls corrosion quite well. Hope this helps.

Derek

[t-spiritpete]

Just ask for a refund or exchange, you do have rights.

[RK123456]

My previous Avensis Tourer, 2009 had the fixpoints become more difficult to put the Thule roof bar fixing bolts into when the car was about 3 years old. I simply ran a tap (M8?) down each threaded hole to clean the threads, no problem.

[Grogey]

Hi,

I used the bolt that came with the roof-bar fixing kit to find a matching bolt at a hardware supplier. I chose an automotive grade bolt as these were high strength. Using both cutting and grinding disks I used a 4" grinder to modify the bolt into a Thread Chaser. See examples of commercially available Thread Chasers, here, (None locally available):

http://www.bikernet.com/news/images/PhotoID38562.jpg

I used this tool with WD40 to clean the threads. It worked well and cost me a few pence. The Thread Chaser ploughs out the corrosion , depositing it in the slots as it turns, with very low risk of cross threading. You work it in a bit, then remove and clean it, depending on how quickly the slots fill up.

I did not consider using the correct tap as:

-The threads were so badly furred up with hard white corrosion that there was a good chance of cross cutting the thread, plus I might simply screw up when using it,

-The fixing point on the Avensis is not replaceable according to Toyota.

Next time the bars come off I'll apply the copper grease.

cheers for the replies.

[coziosco]

Just on the offchance anyone else with the same issue stumbles across this on a google search. My 2010 tourer also had severely corroded mounting points, I sheared a Thule mounting bolt trying to get it in :-(

With a bit of hunting around and chats with a local dealer I've managed to find the replacement parts.

The replacements are now coated, no longer a plain aluminium block prone to corrosion, mine came to £136 for 4 new ones and were pretty straightforward to fit, remove all of the bolt covers on the false rail then lift it up, remove 2 bolts for each mounting point. I gave my gutters a good clean while I was there as they were filled with gunk.

The part code is 63468D

Hope that helps somebody!

C

[Greydog]

If you do end up damaging the threads you can get a local engineering shop to drill them out and fit Helicoil inserts (you could do it at home if you brought the Helicoil Kit) to bring them back to the OEM size. plus the steel insert will be passivated to help protect against rust, a little lube on the fixing bolt will help too. I would think this would be cheaper than buying new replacements from MrT.

[Grogey]

Mr

On 7/19/2016 at 10:58 PM, coziosco said:

Just on the offchance anyone else with the same issue stumbles across this on a google search. My 2010 tourer also had severely corroded mounting points, I sheared a Thule mounting bolt trying to get it in :-(

With a bit of hunting around and chats with a local dealer I've managed to find the replacement parts.

The replacements are now coated, no longer a plain aluminium block prone to corrosion, mine came to £136 for 4 new ones and were pretty straightforward to fit, remove all of the bolt covers on the false rail then lift it up, remove 2 bolts for each mounting point. I gave my gutters a good clean while I was there as they were filled with gunk.

The part code is 63468D

Hope that helps somebody!

C

Mr Toyota told me the aluminium blocks were not replaceable. Nice to see some thorough Toyota dealers.

[coziosco]

They might not have been available at the time, and to be fair the first dealer I contacted didn't think they were available either. I've attached a before and after pic of mine. You can see the new versions are considerably better.

[BigBadTrevsy]

I know this is an old post but if anyone else runs into problems, I managed to break a more modern all-black mount by cross threading the bolt - it's easy to do, corrosion doesn't help. A tracked down a 2009 Tourer at a breakers yard and got the mounts for £20. All corroded, but soaked in vinegar for a bit, used a wire brush and then retapped all the mounting threads with a Draper tapping tool (8mm for the roof bar mount, 6mm for the screws to fix the faux roof rail to. Took half an hour, all sorted.

[WixRob]

I also need to attempt this. Is 8mm the standard size I need to retap to fit the bolts you get in a Thule kit for example?