Loose Flywheel - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

SilviaxDr3aMz · 04-03-2012, 02:30 AM

OK, so i have a 93 coupe. Just spent almost 3k on rebuilding the engine(which has ~700 miles on it now) and numerous tedious things. So when i made the 300 mile trip from Ft. Worth to San Marcos, I changed the oil and a week later alternator goes out and snaps belt. I replace that then as soon as i hit the freeway after fixing it i hear a knock.

I later find out that it was my flywheel and it was loose, My pops comes down and tightens it for me(dont have the tools to do so here on campus). As well as applying lock-tight to insure the hold. He claims to of torqued them as much as possible. Then two days later after a spirited rejoice drive it comes loose again. back to square one.

So questions are, why would it come loose so sudden after? What other parts may influence the flywheel/bolts to do such a thing? Should i go ahead and buy another flywheel+ bolt set?

I also replaced my open dif with a upgraded/rebuilt vLSD, could the added torque capabilities/demand cause the flywheel to loosin the bolts?

Any constructive input or ideas will be a great help. I haft to work and currently driving my roommates SVT Focus... ashamed to be in a USDM car. So a quick reply would be bonus lol.

59bhp · 04-03-2012, 03:24 AM

only thing I could think of would be to replace the bolts for new ones and use a suitable loctite,

there will be quite a bit of localised heat so the loctite used may not be suitable (although doubtful as its not exactly a furnace)

Croustibat · 04-03-2012, 03:41 AM

You may not have the correct bolts. I know 2 different lengths exist, and if you use the bad one, you cant correctly bolt the flywheel.

I am very surprised it did not strip the crank though. Maybe the problem is there .

jr_ss · 04-03-2012, 05:40 AM

If you reused the bolts, there's a good chance they are stretched. Buy new flywheel bolts and torque them to the recommended torque. Red lock tight them as well. You'll need to find a way to keep the motor from turning over when doing this inorder to get the full torque on the bolts. I use a 1/2 rachet on the crank bolt while another person is torquing underneath.

KiLLeR2001 · 04-03-2012, 08:13 AM

New flywheel bolts for M/T, Red loctite, and proper torquing. Do them in a criss-cross pattern tightening them little by little, and then finish off with 100 ft/lbs of torque on all the bolts.

SilviaxDr3aMz · 04-03-2012, 10:13 AM

yea, i did reuse the bolts. Didnt realize that it could would of made a difference.
Ill shoot the information to my pops. Appreciate the quick feedback.

rcdad123 · 04-03-2012, 10:22 AM

also check both mating surfaces of the flywheel and the crankshaft. both have to be smooth and flat. if not, the flywheel will wobble and the bolts will work loose or break.

SilviaxDr3aMz · 04-03-2012, 09:19 PM

Alright, will do...
Also i actually was having power issuse with it. My pops was thinkin that after the car broke in that id get my power band back but it seemed to of been lacking/ lagging when i got on the throttle.
Is this a completely different problem or something related to the flywheel as well? It would make sense if this was considering if the flywheel was loose some power could be lost.
just curious.

KiLLeR2001 · 04-03-2012, 10:05 PM

Quote:

Originally Posted by SilviaxDr3aMz

Alright, will do...
Also i actually was having power issuse with it. My pops was thinkin that after the car broke in that id get my power band back but it seemed to of been lacking/ lagging when i got on the throttle.
Is this a completely different problem or something related to the flywheel as well? It would make sense if this was considering if the flywheel was loose some power could be lost.
just curious.

Yep, same thing happened to me. I would get into the higher rpms and would notice a lack of power almost like a clutch slip. Soon enough I started to hear a rattling sound and I knew right away it was the flywheel.

SilviaxDr3aMz · 04-08-2012, 09:23 PM

Hmm, well... i guess when i manage to get it all back in and together. ill post if this solved all the problems. appreciate the help.

SilviaxDr3aMz · 04-15-2012, 02:37 PM

Well got it all in, only thing is. Replaced the clutch at the same time w/ a Sachs clutch which O'rileys claims to be the new/same standard clutch for 240s. Yet, this clutch seems ridiculously soft. like to the point i feel like i almost haft to pull the clutch up i know i haft to break it in but i fee like this is a little extreme.
How many miles is it till its considered to be broken in anyways?

rcdad123 · 04-15-2012, 03:46 PM

about 250 miles. less if you use the clutch a lot, like stop and go driving. basically, the disc material needs to heat up so it will bond with the metal plate that it is glued and riveted on.

SilviaxDr3aMz · 10-08-2012, 11:26 PM

Yea, i just got a White bunny upgrade and im not 100% sure if that was the cause but i def have a hole in the bell housing which is believed to be caused from the larger pressure plate or w/e.
Anyone know/ herd of that happening?

04-03-2012, 02:30 AM	#1
SilviaxDr3aMz Leaky Injector Join Date: May 2008 Location: San Marcos, TX Posts: 83 Trader Rating: (0) Feedback Score: 0 reviews	Loose Flywheel OK, so i have a 93 coupe. Just spent almost 3k on rebuilding the engine(which has ~700 miles on it now) and numerous tedious things. So when i made the 300 mile trip from Ft. Worth to San Marcos, I changed the oil and a week later alternator goes out and snaps belt. I replace that then as soon as i hit the freeway after fixing it i hear a knock. I later find out that it was my flywheel and it was loose, My pops comes down and tightens it for me(dont have the tools to do so here on campus). As well as applying lock-tight to insure the hold. He claims to of torqued them as much as possible. Then two days later after a spirited rejoice drive it comes loose again. back to square one. So questions are, why would it come loose so sudden after? What other parts may influence the flywheel/bolts to do such a thing? Should i go ahead and buy another flywheel+ bolt set? I also replaced my open dif with a upgraded/rebuilt vLSD, could the added torque capabilities/demand cause the flywheel to loosin the bolts? Any constructive input or ideas will be a great help. I haft to work and currently driving my roommates SVT Focus... ashamed to be in a USDM car. So a quick reply would be bonus lol.

04-03-2012, 05:40 AM	#4
jr_ss Post Whore! Join Date: Dec 2005 Location: Pa Posts: 6,413 Trader Rating: (35) Feedback Score: 35 reviews	If you reused the bolts, there's a good chance they are stretched. Buy new flywheel bolts and torque them to the recommended torque. Red lock tight them as well. You'll need to find a way to keep the motor from turning over when doing this inorder to get the full torque on the bolts. I use a 1/2 rachet on the crank bolt while another person is torquing underneath. __________________ My SR20VET Does your VTC gear rattle in your S14/15 SR? PM me.

04-03-2012, 08:13 AM	#5
KiLLeR2001 Post Whore! Join Date: Jun 2007 Location: オーランドフロリダ Posts: 7,955 Trader Rating: (46) Feedback Score: 46 reviews	New flywheel bolts for M/T, Red loctite, and proper torquing. Do them in a criss-cross pattern tightening them little by little, and then finish off with 100 ft/lbs of torque on all the bolts. __________________

04-03-2012, 03:24 AM	#2
59bhp Zilvia Junkie Join Date: Jun 2010 Location: uk Posts: 379 Trader Rating: (4) Feedback Score: 4 reviews	only thing I could think of would be to replace the bolts for new ones and use a suitable loctite, there will be quite a bit of localised heat so the loctite used may not be suitable (although doubtful as its not exactly a furnace)

04-03-2012, 03:41 AM	#3
Croustibat Nissanaholic! Join Date: Aug 2011 Location: France - Toulouse Age: 43 Posts: 1,851 Trader Rating: (0) Feedback Score: 0 reviews	You may not have the correct bolts. I know 2 different lengths exist, and if you use the bad one, you cant correctly bolt the flywheel. I am very surprised it did not strip the crank though. Maybe the problem is there .

04-03-2012, 10:13 AM	#6
SilviaxDr3aMz Leaky Injector Join Date: May 2008 Location: San Marcos, TX Posts: 83 Trader Rating: (0) Feedback Score: 0 reviews	yea, i did reuse the bolts. Didnt realize that it could would of made a difference. Ill shoot the information to my pops. Appreciate the quick feedback.

04-03-2012, 10:22 AM	#7
rcdad123 Zilvia Addict Join Date: Jul 2011 Location: san diego Posts: 639 Trader Rating: (0) Feedback Score: 0 reviews	also check both mating surfaces of the flywheel and the crankshaft. both have to be smooth and flat. if not, the flywheel will wobble and the bolts will work loose or break.

04-03-2012, 09:19 PM	#8
SilviaxDr3aMz Leaky Injector Join Date: May 2008 Location: San Marcos, TX Posts: 83 Trader Rating: (0) Feedback Score: 0 reviews	Alright, will do... Also i actually was having power issuse with it. My pops was thinkin that after the car broke in that id get my power band back but it seemed to of been lacking/ lagging when i got on the throttle. Is this a completely different problem or something related to the flywheel as well? It would make sense if this was considering if the flywheel was loose some power could be lost. just curious.

04-08-2012, 09:23 PM	#10
SilviaxDr3aMz Leaky Injector Join Date: May 2008 Location: San Marcos, TX Posts: 83 Trader Rating: (0) Feedback Score: 0 reviews	Hmm, well... i guess when i manage to get it all back in and together. ill post if this solved all the problems. appreciate the help.

04-15-2012, 02:37 PM	#11
SilviaxDr3aMz Leaky Injector Join Date: May 2008 Location: San Marcos, TX Posts: 83 Trader Rating: (0) Feedback Score: 0 reviews	Well got it all in, only thing is. Replaced the clutch at the same time w/ a Sachs clutch which O'rileys claims to be the new/same standard clutch for 240s. Yet, this clutch seems ridiculously soft. like to the point i feel like i almost haft to pull the clutch up i know i haft to break it in but i fee like this is a little extreme. How many miles is it till its considered to be broken in anyways?

04-15-2012, 03:46 PM	#12
rcdad123 Zilvia Addict Join Date: Jul 2011 Location: san diego Posts: 639 Trader Rating: (0) Feedback Score: 0 reviews	about 250 miles. less if you use the clutch a lot, like stop and go driving. basically, the disc material needs to heat up so it will bond with the metal plate that it is glued and riveted on.

10-08-2012, 11:26 PM	#13
SilviaxDr3aMz Leaky Injector Join Date: May 2008 Location: San Marcos, TX Posts: 83 Trader Rating: (0) Feedback Score: 0 reviews	Yea, i just got a White bunny upgrade and im not 100% sure if that was the cause but i def have a hole in the bell housing which is believed to be caused from the larger pressure plate or w/e. Anyone know/ herd of that happening?