NB valve shim change

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RS2000
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NB valve shim change

Postby RS2000 » Mon Jul 25, 2016 11:21 pm

I have 4 exhaust valve clearances out of spec, & would prefer not to disturb camshaft.
What tools are recommended to remove shims ?
Do http://www.autotools.com.au/catalogue/p ... /1/AT88250 work easily or easily cause damage?

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Re: NB valve shim change

Postby C-Gazer » Tue Jul 26, 2016 12:49 am

This is a bit rough but it works. I used 2 flat blade screwdrivers. The first screwdriver was used to push the bucket holding the shim down then the other screwdriver was used to wedge the other side of the bucket while the shim was lifted out with a magnet. You need to have the exact sized screwdrivers which fit under the edge of the bucket and the camshaft. Wrap some tape around each screwdriver to prevent damage and wear safety glasses. The camshaft lobe has to be clear of the shim you are trying to remove of course. Shims are available from Melbourne. Good Luck!

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hks_kansei
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Re: NB valve shim change

Postby hks_kansei » Tue Jul 26, 2016 8:58 am

I genuinely think removing the cam will be far faster and less likely to damage anything with a slipped screwdriver gouging a lobe etc.

If you don't want to 're do timing, you can cable tie the timing belt to he cam gears and remove the centre bolt which holds the cam to the gear.
With the rear retainer off you should have enough room to remove just the camshaft without having to touch the gear
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rascal
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Re: NB valve shim change

Postby rascal » Tue Jul 26, 2016 10:03 am

You can get one of these off Mazda...
Image
Not cheap but works well enough if you really dont want to pull the cams out. (although if you have SUBs you'll have to pull the cams regardless)
However I've used one and tbh anything more than a couple of shim changes and its quicker to just pull the cams.
As hks_Kansei mentioned, you can just cable tie the gears to the belt so you don't need to retime..

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Re: NB valve shim change

Postby and1 » Tue Jul 26, 2016 11:42 am

Ditto about removing cam. Much easier and faster. Also I have a ton of spare shims now that I had to do all valves. Let me know what you need and I can have a look see if I have one in that size.
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RS2000
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Re: NB valve shim change

Postby RS2000 » Wed Jul 27, 2016 8:36 am

Thanks all for replies.
I guess you mean it's easier & quicker to remove camshafts for shim changes, if the front of the engine is already dismantled? However a tool (or screwdrivers!) allow shim changes with just the removal of the valve cover.
Anyway, I'm doing the full timing belt, water pump etc change including cam front seals, so may as well pull camshafts out.

C-Gazer - where/who in Melbourne sell shims?
and1- I will let you know what I require

Cheers

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hks_kansei
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Re: NB valve shim change

Postby hks_kansei » Wed Jul 27, 2016 8:54 am

You shouldn't need to remove anything more than the valve cover to remove cams.

You simply undo the bolt in he middle of the cam gears (accessible with just valve cover off) and then undo the cam retainers (located along the cam under the valve cover)

The cams can then be lifted out, leaving the gears in place so you don't need to take anything further off.

You just need to cable tie the timing belt tightly onto the gears in a couple of places so that it can't slip off, and you won't even need to reset the timing.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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hks_kansei
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Re: NB valve shim change

Postby hks_kansei » Wed Jul 27, 2016 8:55 am

As for shims, try bursons etc.

They sell Welsh plugs, piston rings, and most of he other rebuild related parts, they should also have shims.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

RS2000
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Re: NB valve shim change

Postby RS2000 » Wed Jul 27, 2016 9:24 am

Cheers hks, makes sense

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Re: NB valve shim change

Postby rascal » Wed Jul 27, 2016 9:56 am

RS2000 wrote:C-Gazer - where/who in Melbourne sell shims?

I've found Precision Shims in Croydon are good for shims. Good prices, and prompt service, (usually post out overnight, or can pick up that day)

Conatct; Chris @ Precision Shims- 4 Fay Court, Croydon. Ph 9723 0199

RS2000
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Re: NB valve shim change

Postby RS2000 » Thu Jul 28, 2016 8:28 pm

Cheers rascal


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