Flywheel Bolts

[9elf]

Ladies and Gentlemen,

Just a quicky from a novice.

Can I use an air driven impact wrench on these flywheel bolts?

Thank you in advance.

[Porschekid962]

yes and for good measure a little spray of PB and it will be off in no time. after this and the front pulley you wont need an impact for anything, maybe a rabbit to speed up teardown if your goin there...

[9elf]

Thanks porschekid, I am paranoid about stripping these bolts.

What is PB?

[Rot 911]

PB = Parts blaster penetrating spray. Although it is rare to see rust on these bolts a little PB couldn't hurt. I also use the impact wrench on these bolts.

[rsscotty]

I personally don't ever use the impact gun to loosen or install the flywheel bolts. Lock the flywheel and them loosen with a breaker bar, then use the impact for final removal. Depending on the quality and condition of your tool, sometimes the splines are damaged or don't fit well, then you have a bolt with torn up splines.
Porsche recommends replacing these bolts after one use.

Hope this helps.

[kenikh]

Mine came off with a standard 18" breaker bar and my 230 lbs leaning into it. It was cake. If I'd had and impact gun, I'd have used it though.

[ChrisBennet]

Originally posted by rsscotty
I personally don't ever use the impact gun to loosen or install the flywheel bolts. Lock the flywheel and them loosen with a breaker bar, then use the impact for final removal. Depending on the quality and condition of your tool, sometimes the splines are damaged or don't fit well, then you have a bolt with torn up splines.
Porsche recommends replacing these bolts after one use.

Hope this helps.

I always replace them but I've never seen where Porsche has recommended replacing them (pre 964). Do you remember where you saw that?
-Chris

[bbh03]

Wayne recommends it. I don't know where the idea originated from though.

[rsscotty]

Chris,

Started with a Porsche dealership back in '72 and it became standard operating procedure to replace the bolts on 911 and 914 flywheels.

When we were seeing the head of the bolts break off and fall into the pressure plate clutch area you took precautions for future jobs so you didn't have to do them twice.

There was a time a few years back where we were getting the bolts from an aftermarket supplier. They were junk..you could feel them stretching just to make stock torque specs.

We torque the factory "good" bolts to 140 ft. lbs. on our race flywheels so they don't come loose. No loctite or lube used.
Standard torque on street setups.

[Steve@Rennsport]

Originally posted by rsscotty
Chris,

Started with a Porsche dealership back in '72 and it became standard operating procedure to replace the bolts on 911 and 914 flywheels.

When we were seeing the head of the bolts break off and fall into the pressure plate clutch area you took precautions for future jobs so you didn't have to do them twice.

There was a time a few years back where we were getting the bolts from an aftermarket supplier. They were junk..you could feel them stretching just to make stock torque specs.

We torque the factory "good" bolts to 140 ft. lbs. on our race flywheels so they don't come loose. No loctite or lube used.
Standard torque on street setups.

And this fellow knows what he's talking about,.....

[dean]

I don't think that tool is designed for impact use. So I wouldn't use one.

One time I tried to save the $60 on flywheel bolts. As I was tightening up the flywheel two of the 6 bolt heads sheared right off. Yikes. I replace them now.