Precat removal - How I did it...

[Lurch]

Here is a very similar thing over on Spyderweb with pictures

Thanks mate superb just what i required,
Cheers again.

[Lurch]

Removed my precats this morning all done and dusted in two hours, found them totally intact but then again have only done 7060 miles from new but can now have total peace of mind . Thanks for all help I found on this forum.
Cheers.

[StuC]

Glad to hear it went well. Any issues with any of the fixings during the removal or reinstallation?

[Lurch]

None what's so ever mate , everything came off easily, suppose as its not been used a lot made it easier, oh apart from when i dropped one of the cat fixing bolts into the exhaust down pipe! Total cost £16.40 for new manifold gasket. Had replaced the other two less than 100 miles ago when I fitted the TTE twin exhaust.

[Maverikk]

So me and and my mechanic friend went to de-cat the thing today, and it turns out that a previous owner had already done it! Bit of a result, really. One of the 02 sockets was a bit of a pain to get off, as the last person to put it back on had apparently cross-threaded it. I am 99% certain the cats are not in there, but here are two pics if anybody feels like confirming it. (On the pre-de-cat pics I've seen, the cats are clearly visible near the top of the hole.) I also stuck a 7 inch screwdriver in there and had a good poke around and there was nothing laying around or on the sides so it appears to be all clear.

Now, just off to Toyota to get a refund on the parts I bough in case they were needed (bolts and gaskets)!   s:lol: :lol: s:lol:  

 m http://imageshack.us/photo/my-images/202/leftgo.jpg/ m    
 m http://imageshack.us/photo/my-images/442/rightjh.jpg/ m

[StuC]

Looks pretty empty to me! Result!  :-) :-) :-)

[Maverikk]

Yeah, proper result, innit? I haven't really put the 2 through its paces yet, for fear of damaging the pre-cats. But now I know they're not there, well...

[AckersMR2]

Good luck with returning the bolts etc, apparently if its parts they ordered in especially then Toyota UK (or Europe or Japan wherever they got them from) will not accept returns unless each individual item is valued at over £20 or £25? Unless that was just my Toyota dealer telling me that?

I'm sure you'll be able to offload them on here though, I sold my cylinder head studs and nuts to another member for face value, I threw in the postage I think?

[StuC]

Good luck with returning the bolts etc, apparently if its parts they ordered in especially then Toyota UK (or Europe or Japan wherever they got them from) will not accept returns unless each individual item is valued at over £20 or £25? Unless that was just my Toyota dealer telling me that?

I'm sure you'll be able to offload them on here though, I sold my cylinder head studs and nuts to another member for face value, I threw in the postage I think?

+1, always newbies going through pre-cat removal pain on here!  s:lol: :lol: s:lol:

[Wabbitkilla]

[Admin] Just so you know I now have the images that were originally attached to this ... I will be re-adding them in the near future. [/Admin]

[StuC]

Good stuff  :-) :-) :-)

[Maverikk]

Good luck with returning the bolts etc, apparently if its parts they ordered in especially then Toyota UK (or Europe or Japan wherever they got them from) will not accept returns unless each individual item is valued at over £20 or £25? Unless that was just my Toyota dealer telling me that?

I'm sure you'll be able to offload them on here though, I sold my cylinder head studs and nuts to another member for face value, I threw in the postage I think?

No problems here.   s8) s8)

[charl1ey]

Ok, chaps (& chapesses)...

I think Ive just about read almost all the threads I can find about my pre/cat removal.

Just got a couple of queries before i start.

So Ive started to plus gas the studs/nuts.

Im thinking of getting some replacement gaskets/nuts and studs in case there are any dramas as I will need to refix it all so i can drive back home on the bank holiday monday.

Question is I have come across 2 different part numbers for gaskets etc. and just want to check before i order them from Chris at CTP, please can you tell me exactly what i need to cover the worst case of all nuts / studs going.

17173-22010 - Manifold to Block gasket - £22.57
90917-06065 - Cat to Manifold 'donut' gasket (need 2) - £4.46 (£8.92)
90116-10146 - Studs (need 3) - £2.16 (£6.48)
90179-10070 - Nuts (need 3) - £2.05 (£6.15)

or?

Parts you will need:
One (1) Engine to Manifold Gasket: Part# 17173-0D020
Two (2) Manifold to Downpipe Gaskets: Part# 90080-43036

Parts that shouldn't be reused (even though some do):
Three (3) Manifold to Downpipe Nuts: Part# 90080-17187
Five (5) Engine to Manifold Nuts: Part# 90179-08228

Parts you won't need unless something goes wrong:
Five (5) Engine to Manifold Studs: Part# 90126-08037
Three (3) Manifold to Downpipe Studs: Part# 90116-10146

Also one final Q, all these parts plus my 02 socket and plus gas comes to about £60 and thats halfway towards just buying a new Jdmhonda manifold off fleabay... is there any noticeable performance or quality benefit between gutting my existing or spending the extra £60 on a new one which apparently comes with the gaskets nuts/studs etc.  s:? :? s:?

ps looks like easier access to refill my gearbox oil at the same time as when the manifold is out!

Cheers in advance...

[AndyM]

I'm working out what to do about my precats at the moment too. A couple of points...

The supplied gaskets with the manifolds are apparently a bit rubbish so it is recommended you still buy the Toyota ones. You'll also still need the tools/plusgas/studs/nuts. As such the actual cost difference will be the full £120.

I have been weighing it up and decided I'll still change the whole manifold when I can, just to get that tiny bit of performance (and shiny steel) instead of paying out for the bits just to fit the gutted one back on.

Also, you might want to consider some heat wrapping?

On the gearbox oil... I'm sure it might provide a bit more room but I managed to change mine this weekend without any hassle or removing bits. If you have time then go for it, but if a pesky nut eats in to your day it's easy enough to do the oil at a later date.

[OldMan]

I have been weighing it up and decided I'll still change the whole manifold when I can, just to get that tiny bit of performance (and shiny steel) instead of paying out for the bits just to fit the gutted one back on.

That's a very bad decision, my friend.
What you'll gain is a loss of funds and problems in future.

[AndyM]

That's a very bad decision, my friend.
What you'll gain is a loss of funds and problems in future.

Can you elaborate? Or do you mean that you think you think it's a bad decision that I'm not doing it immediately?

[charl1ey]

think the advice from old man is gut the existing manifold. new fleabay ones are made from cheaper materials and don't wear aswell, eg may crack.

[GSB]

[Admin] Just so you know I now have the images that were originally attached to this ... I will be re-adding them in the near future. [/Admin]

Did you forget WK?

Just re-upped them and placed them in my original how to guide for posterity...  s:wink: :wink: s:wink:

[charl1ey]

Pfff.... Ok so am mid removal.

Have lost a lot of skin of most knuckles, have sworn a lot and had a few childish tantrums. But finally upper and lower heat shields are off. All 5 manifold header nuts are off. 2 of my 3 Amigos have sheared through leaving half of them still in situ holding the manifold to the cat, and one of my 3 amigos is like doesn't look like the others? It looks like a bolt and now I've loosened it it just keeps turning but not actually coming out!?

So questions are how do I go about drilling out the sheared off amigos what size drill bit and will I damage the thread for my new bolts?

Also why is the, left hand side when lying under the car, amigo, a nut that just keeps turning and not coming out? Shall I just Dremel that off?

I read that this could either be a 2 hour or a 2 day job... Well it's turning into the latter and I need to get this bloody thing off gutted and back on by Monday so I can drive home!

Help appreciated!

[charl1ey]

Just realised how bad this is after googling how to remove sheared off bolts. It looks like im going to have to get a left handed drill bit? is this correct, do I have to drill them from the top or from under the car? here is a pic of the 2 sheared off bolts on my manifold



And here's the 3rd Amigo on the left hand side, which doesn't look like the others? it isn't a nut but a bolt and its loosened off but just spinning round and not coming out, very odd. I think Im pretty screwed here, no pun intended and may need some professional help. also trying to do this on my back with my car on axle stands with my nose on the cat pipe isn't helping!



and here are the 2 sheared off 'amigo's'... to be honest I think we should rename them Diablos, because they certainly aren't amigos!!!



Help!
  s:cry: :cry: s:cry:

[Wabbitkilla]

One reason why those replacement headers are a good idea. That last amigo looks like a bolt head, it's been replaced for some reason (it's been off before) there will be a nut the other end of it which.is why it's just spinning.

[AckersMR2]

One reason why those replacement headers are a good idea.

+1
If there's a nut and bolt in there then sounds like one of the bolts has been drilled out before and the original thread drilled out with it?

[simers]

One reason why those replacement headers are a good idea.

+1
If there's a nut and bolt in there then sounds like one of the bolts has been drilled out before and the original thread drilled out with it?

If that is the case could it be that pre-cats have already been removed or has the op in question already checked to see if there... I could be misguided in my presumption here tho and stand to be corrected if so...

[GSB]

Oh dear, that does look bad. The only option that I can see is to cut off the head of the loose bolt, and the drill through the knackered remains of the sheared bolts and tap them out to a larger size. You could then drill the holes out on the cat flange and use bigger bolts.

Bit of a ball ache though, and I'd suggest that a replacement manifold would be a better bet if you can get one.

I have one, a brand new unit with all its studs intact that was removed the day I bought my long since sold '04 '2 from Barnet Toyota. But it's in Enfield, and I'm not. I could drive over in the morning and pick it up, but you'd then need to get to East London to get it from me.

[george_m]

My first post here as this is my first Mk 3 to own as I have been running a Mk2  3sgte Turbo for over 8 years

Just finished removing my pre cats from my 2000 model I bought recently, what a pain every bolt seized solid. It took a lot of heat on some bolts others had to be drilled or angle ground out. On inspection one precat was ok the other was on its way out  not a moment too soon.