My TF has just clicked over 295k and I'm wanting to replace the timing belt and have seen a few kits on Ebay for around $150 so figured since I've done just about everything else on it apart from this I would give it a go too.

Is it a tough job to do? Does the engine need to come out or anything and what is the best way to do it for someone with reasonable knowledge of DIY stuff?

Without the proper tools and a torque wrench I wouldn't do it.

Your going to need this (OEM knockoff, fantastic quality)
http://cgi.ebay.com/ebaymotors/Mitsubishi-3000GT-DSM-Montero-EVO-Timing-Tensioner-Tool-_W0QQcmdZViewItemQQhashZitem27b22506cfQQitemZ17049 2495567QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccesso ries
and a torque wrench personally wouldnt do it by feel. besides that it's very DIYable but if you havent worked on these car's before i wouldn't be starting with the T/belt

Agreed i had mine done by a pro although it set me back $506 i looked afterwards to see what is involved and i was pretty glad that i didnt tackle it myself. On a funny note mine wasnt done till 315xxxk's.

Although I've never done one on a Magna, I'd have no hestitation in doing mine mainly because I don't like throwing away the $6-800 in labour costs involved. The cam tensioner tool is easily fabricated or bought. First I'd thoroughly research what is involved including buying a workshop manual. You can usually borrow a tension wrench although $50 will buy one. The rest of the tools will already be in the posession of most people who do their own repairs. I have done the belt, tensioner and waterpump on my wife's New Beetle which is a very similar setup. No rocket science is involved.
So my advice FWIW is to use the search engine on this forum plus Google....then it's up to you to decide. Good Luck.

pretty much. Also, you'll need 1/2" and 1/4" torque wrench to do it "by the book"

If you don't want to buy the tool (which i highly recommend have one myself) two allen keys held together will also swing the tensioner.

Do you have a record of what was done when the belt was changed last? If the idlers, water pump and seals were done at the 200,000 Km mark you may not need to change these. If you don't have a record, best to change them.

Engine doesn't need to come out but you need to know the correct procedure, and special tools like the tensioner tool, a torque wrench and torque wrench settings for all the bolts you remove to get to the belt.

Did mine on a first gen v6 for the first time a while back, piece of cake really.

Sounds like it's fairly doable. I'll get those tools and then give it a go when they come in then.

i attacked an old socket with an angle grinder to make the preloading tool... worst part was removing the engine mount from the tight gap between the engine and engine bay (mine is a 3.5 so i dont know if there is more room on the 3).
due to the magnitude of the job it would be in your best interest to go for the full kit w/seals and H.A.T, and due to the age i would err on the side of caution and do the water pump.

Nm torque
Auto tensioner bolt 24
Tensioner pulley bolt 49
Tensioner arm bolt 44
Idler pulley bolt 44
Camshaft sprocket bolt 88
Tensioner pulley preload 4.4

i know that she's getting on but while in there why not do the cam adjustment mod :woot:

i did mine a couple of weeks ago. using a preloading tool is best for the inexperienced as the tension may change when the lock bolt is torqued up to specs. holding the bearing firm with a tool may prevent that.
as for the engine mounting bracket , i was able to manouver the old belt out and the new belt in when all the bracket mounting bolts were removed from the block.
to remove the mounting bracket from the engine completely it may be neccessary to remove the left side cam sprocket.

Although it's not a Magna, the writeup on this page is a pretty good guide to changing the belt on a 6G74 -

http://www.club3g.com/forum/maintenance/118492-how-change-timing-belt-v6-pictures.html

that was a great writeup. its real important to triple check that all the marks line up properly too. i almost put it back together with the crank one tooth out as the crank moved while i was tensioning up the idler.

ha all got mine done at 150k and at 200k bearing failed had access to car hoist made the job easy had to remove engine mount only setting cam marks while tentioning was two man job get it dont dont delay