Check your crossmembers

[Anonymous]

I've certainly seen a lot of holed crossmembers (aka rear sub-frame).  As D!ck points out, if you're replacing one the track arm bolts (I'm sure that's what he meant as opposed to camber bolts  s:wink: :wink: s:wink: ) are often seized and generally impossible to remove without destroying them so it may be best to get the track arms with the replacement member.

MOT stations generally can't see it when the undertrays are on which might explain why it shows up on some tests and not others. (These days, having the undertrays on at MOT is an advisory notice pointing out that they cannot see components covered by them!).

That said, I reckon Nic's experience of having to replace it three times is not typical, but I certainly agree that checking it and doing what you can to arrest any corrosion that might be present (specifically the area where the exhaust passes) is a vital step.

Im just quoting Toyotas own parts list, Bolt, Camber Adjust, part number 48190-32010.   s:? :? s:?

[MattPerformance]

I'm just quoting Toyotas own parts list, Bolt, Camber Adjust, part number 48190-32010.   s:? :? s:?

It's a cam bolt that adjusts the track.  Must be a translation thing?!?!  Glad it wasn't your error though D!ck   s:P s:P

[Wabbitkilla]

For info my first crossmember was damaged while trying to remove corroded toe adjustment bolts. Apart from that it was in good shape.

As Matt says it's worth getting diwn there with a torch and check it out, it is a vital part of the rear suspension.

Sent from a planet somewhere nearby

[MisterK]

Just been under the rear of my car this morning as the paint had started to peel off the rear ant roll bar, so decided to treat it with Hammerite Kurust and Black Hammerite Smooth.  Whilst there and with the nappy off I checked out the crossmember from underneath & above.  Quite a lot of surface rust but otherwise everything looks solid and no holes or 'bendy' bits - from above it looks fine, so you do need to get under the car.  Treated the exposed rusty bits with the Kurust & sprayed everything with WD40.  Obviously this won't help at all if it's rusting from the inside out.   s:( s:(    Car only done 40K & kept in a garage since new, so hoping the crossmember will last for some years to come.   s:D s:D

[steve b]

I just ordered a new crossmember from CTP and new toe link bolts.  I wondering about modifications before fitting, seems silkaflex it all sealed up from the top, leaving drain holes obviously a good idea.  Maybe weld an extra layer of steel over the area by the exhaust to act as a heat shield?  Fill it with waxoil.

[MattPerformance]

Personally I'd fill it with expanding foam then out some heat shield over the area by the exhaust.

[steve b]

Why expanding foam?

[Jay67]

so you don't leave a void for condensation to occur? Fill it with foam, nowhere for moisture to gather. Probably wrong but no harm in having a guess!  s:) s:)

[steve b]

Could be, but isn't expanding foam a bit like a big sponge?  Open to suggestions as want my new one to stay like new as long as possible.

[steve b]

 m http://forum.miata.net/vb/showthread.php?t=323732 m

Found this researching - not builders foam, special expensive stuff.

[jonty]

the infiniti Q45 stuff and other products sounds a lot better than the stupid priced BMW stuff... that could be well worth a look, people talking $100 which in the scheme of things is peanuts...  s:D s:D

[Wabbitkilla]

Trouble is we only think of these things once the rot has set in   s:( s:(  
If you're buying a new cross member then it's worth protecting it as much as possible.

[jonty]

Yeah I agree, definitely worth protecting! I haven't looked at mine (haven't looked at the car in months as it's parked with a blown engine) but before it goes back on the road I'll be checking and replacing the crossmember if required - I'll have doubled the power so probably best to have a nice positive location for the rear end!!

[steve b]

I was amazed how much mine had gone - to the extent by the toe link on the exhaust side I wouldn't pass it if I was an mot man.  Above exhaust all holler as well.  Rest of it looked like new, from the top and a blemish.

[steve b]

New crossmember arrived today  :-) :-) :-)  Tight arse Toyota though, I ordered new camber bolts as don't want to use rusty old ones and all that was in the packets were the bolt bit not the nut bit!  Who orders one half of a camber bolt???

[steve b]

One new cross member  :-) :-) :-)  so, I'm definitely going to paint it again as paint on the welds is flaking off from new.

Decided to do a full over haul so have full rear CHE arms to go on.



Plus Speed source engine mounts, I got some extra mounts and have fitted the new bushes in them ready and BC Coilover are on order  :-) :-) :-)

Really need to decide on ride height and geometry now in addition to cross member rust proofing.  Any handy hints and tips for when I do the work, actually replacing all these bits?

[tomaky]

Slightly related had car on ramps today removing rear bumper noticed general rust i was thinking of wire brushing then adding some sort of rust prevention then potentially spraying in plasticote good or bad idea? Any other advise welcome.

[spit]

That'd be better than ignoring it Tom   s:wink: :wink: s:wink:  

Not sure about Plasticote to finish it off though. There are probably better products out there to seal and protect exposed and treated metal.

As with most things though, its all about preparation. Get a good surface for paint to key to and you'll get a longer lasting result.

[tomaky]

Aii its not to bad underneath just im one person who has never liked rust, might have a more specified look at cross members but from memory they were pretty good. Id like to prevent further rusting. Maybe have a good scrat around the net on my few days off this week.

[2 of the left]

If you can get to an HM Dockyard - Have a word with a Dockyard worker or Sailor to supply you with 1 gal. of Red Admar (Paint used to deter rust on HM Warships) - " Proper Job !! "  s:wink: :wink: s:wink:

[tomaky]

Going to pm you something haha

[kentsmudger]

http://forum.miata.net/vb/showthread.php?t=323732

Found this researching - not builders foam, special expensive stuff.

Just noticed this - Look like interesting stuff for several reasons

[Mark080]

I was changing my exhaust manifold today for a stainless one with no cat as I was paranoid of the dreaded cat material breaking up and wrecking my engine.  I saw some holes in my cross member while I was under there so decided to remove it as it would make things easier anyway.  I was wondering if if is worth getting welded or is replacement always the best option?  It has a small hole on top, on one side and  a largish one underneath. Inspecting inside doesn't look too bad.  I've attached a picture of the large crack/hole.  Thanks in advance.

[spit]

I've seen much worse get welded up and through a couple of years of MOT. If its done well its probably worth having it done, but then there's always that nagging thought in your mind which'll take the edge off any spirited driving.

We've also seen some really shoddy flat plate weld jobs done on these - probably while they're still on the car. The fact that you've got it off is a bonus for ease of repairing.

Tough call though, and I'd say that if you're into '2 ownership for the duration, replace it. A quality welding job would cost a fair chunk of the £250 to replace with a shiny shiny.

[2 of the left]

That is deffo a replacement needed!! (The weld would be the strongest point!!)