Can I reuse flywheel bolts?
 

Hey All,

I am getting ready to mate my transmission and engine. Can I reuse the flywheel to crank bolts and the pressure plate to flywheel bolts?

Thanks,
-Raj

I do, I just use loctite. Some others may not like it but I have always reused the same bolts

Apparently some flywheel bolts on other cars are torque-to-yield units.

Meaning you torque the bolts to the point that they begin to yeild, or stretch, making them a single use bolt.

The Miata does NOT use this type of bolt, and unless otherwise damaged, can be reused a number of times.

Thanks for the info guys.

-Raj

I re-used my flywheel bolts. What bolts on a Miata engine are "torq to yield"?

I know you can re-use the head bolts, as for torque to yield on a miata I don't know of any. Someone else may be able to tell you more than me, but I know you can reuse head/flywheel bolts

clean em, lock-tite em and you're set.
ive done this dozens of times on a miata

Normally you should ask yourself "is it worth not spending a few bucks for new hardware?" but in this case, yeah. Loctite/Permatex red is your friend

Off the top of my head, the hub nuts are TTY. The head studs and the flywheel bolts are not.

I've heard crank bolts shouldnt be reused.. Any juice on that?

Don't re-use the ones on early small nose 1.6L's all the rest are fine.

Bob

I've never re-used a crank bolt, ever. FSM says it is TTY.

I re-use them. Never had an issue. Haven’t been to ---- about the torque ether. I Also started using lock tight green sleeve retainer with stock pulleys.

With the ATI dampers however the pulley is a very tight interference fit. I use ARP molly lube to get it to pull on and I use one bolt to get it pressed on then put another in and torque it. I don’t think those things would come loose if you took the bolt out and lost the woodruff key they fit so tight.

I had my first 1.6l crank nose snap off in 1994. About 15k miles post dealer performed timing belt change. And I have seen multiple failures and stretched bolts on small nose 1.6l. The bolts are much smaller diameter than 1.8l.

The early 1.6 to 1.8l crank pulley bolt size difference is huge

Bob

:eek:

Now ask me how many times I've torqued mine. The answer is probably around a dozen. Am I on borrowed time?

I overtorqued mine so I had to replace them. It was a cheap fix.

Yea I think I’m around a dozen I have seen no signs of yielding. Wouldn't do that with the small nose 1.6l though. I think when Mazda fixed the problem they went for overkill with a simple design change.

Putting on the ATI damper though it requires so much torque to just get the thing pulled on it tends to gall under the head of the bolt. I install with a washer to snug it up with an impact then use a different bolt to apply final torque.


Bob

The FSM says it's TTY, and your motor is junk if it ever comes loose. I'll stick to replacing it.

Bolts of flywheel I re-used two times then I was change. Now I have the arp of ford is was the same with Miata

if they are only a few $ i imagine its worth spending the money then pulling the trans because of some odd occurrence.