Crankshaft Seal - Flywheel Bolts.....

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kevtherev
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Re: Crankshaft Seal - Flywheel Bolts.....

Post by kevtherev »

tencentlife wrote:
Mainseal leaks are the norm, but there are several galley plugs in the bellhousing end of the crankcase, sometimes these leak, too. The 1/2" one for the main galley (in the left case half) is the most notorious. You should preclude their leaking while you have access, the quick n' dirty way is to clean off and rough sand the plugs and a patch surrounding them, degrease, and apply a cap of JB Weld over each.

good tip

The flywheel bolts are not TTY (torque-to-yield, aka "stretch bolts") so they are not single use only. Why this myth persists is also something I don't understand ( a TTY fastener is easily identified by its torquing spec saying "torque to x pounds and then turn x degrees further"; the wbx FW bolts have a simple torque spec). You can reuse your old ones with assurance, again and again, uness you bugger out the sockets. They are 10mm in-hex, final torque is 80 ft.lb. Use a little Loctite on the threads for the final tightening. Having a VW flywheel lock is also very useful here, they can be had from any VW aftermarket parts supplier for less than $10 (what's that, 6 pounds?)
The myth perpetuates due to Haynes manual tencent, it stipulates bolt renewal.
But that solves T25converts dilemma ...thanks

Spend a little on a dial indicator and holder (only $30 here gets you both, so many uses). You will want to check the crankshaft endplay and adjust it if it is out of spec, or your new mainseal may leak too. If the case is an old-style 1.9 with a flanged #1 thrust bearing you will also want to check that the thrust bearing is not moving axially in the case, or your efforts will also come to naught.
Could you expand on this checking of end play?

Mainseals get replaced again and again because people neglect to deal with the flywheel hub which has to ride in the seal. Wbx's run long enough without needing teardown (as opposed to aircooleds) that a groove develops on the flywheel hub. If you put the flywheel back without dealing with the groove it will just leak again, immediately. If the groove is deep enough to catch your fingernail in, it's too far gone and you're into a new flywheel. If it's less than that, the groove can be sanded and polished out by spinning the flywheel slowly while using progressively finer grades of sandpaper, starting with a 40grit and progressing bit by bit to about 1000grit, so the groove is gone and there is a fine polish on the hub. This is the only way to guarantee a dry seal.

Having the flywheel off it's a good time to get it resurfaced by a machinist, and install new clutch components if indiacted. At minimum, even if pressure plate and disc are OK, put in a fresh throw-out bearing**. The TOB** is the life-limiter on a clutch (first thing to wear out) so why not buy time 'til the next time this needs to be done?

You'll also have the driveaxles at least halfway out; if they haven't been relubed and rebooted in awhile, here's your chance.

Some valid points there mate thanks

**we call that a thrust bearing and they come complete with the clutch in a kit From GSF
AGG 2.0L 8V. (Golf GTi MkIII)

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toomanytoys
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Re: Crankshaft Seal - Flywheel Bolts.....

Post by toomanytoys »

WHS^^^^^^^

Flywheel bolts ARE NOT single use...
as said fit a new o ring..
spot of grease in the spigot bearing (in end of the crank) too or if its rough, replace...

Also you want to take a look at the ends of the clutch releas fork these should be nice and rounded, if flat you can reprofile with a file but if well worn, require a spot of weld on them to bring them back up, then round off.. fit a new release bearing then as the old one will wear it out..

CV bolts.. clean the bolts and the serrated washers before reinstalling..

"TOB = throw out bearing".. is a "clutch release bearing" not known (where I come from) as a "thrust bearing"..

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T25Convert
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Re: Crankshaft Seal - Flywheel Bolts.....

Post by T25Convert »

Evening all,

Thanks for the detailed assistance with this - you've answered all my questions, and some I didn't even know I had! Makes sense about checking end-float, as presumably if you don't is will just push the new seal back out, likewise the possible wear in the flywheel.

Thanks also for the detailed instructions on my clutch release bearing and release forks. If funds permit I'll probably stuff a whole new clutch in, while its all in pieces anyway....

Glad to have the bolt issue sorted - I've been going round in circles in my head.

I've ordered the seal, shims and o-ring, and will be sorting out the dial gauge this weekend, so next weekend I'll have a stab at this.

Until then (when it all goes wrong), I'll leave you all in peace.......

Cheers,

Alex
RIP - George - 1.9DG '85 AutoSleeper Trident - rusted away

George Second - 1.9DG '89 Caravelle

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