Flywheel removal.

[Reptoid Overlords]

Has anyone experienced a situation in which removing flywheel bolts without using air tools does NOT spin then engine without being held?

 

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[gnosez]

Of course. At 100 to 160 ft/lbs with the engine hanging on a hoist it will spin unless you have a way to stop the engine from turning.

A second person holding a breaker bar and socket on the crank pulley nut works as long as they weigh enough. Or you can jam a large screwdriver or bolt to engage the teeth on the flywheel.

In air, we trust...

[Reptoid Overlords]

When removing the flywheel bolts, I put a breaker bar in the flywheel teeth to keep the engine from turning. The bar slipped, but I noticed the engine would still not turn as I ratcheted the flywheel bolts out.

Apologies, I should've been more specific in the original post.

It will spin in the normal direction of operation. Of course, I'm not going to try and spin it backwards to see.

I guess I'm a bit worried at how easy the flywheel bolts came out.

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[gnosez]

I too would be worried (after the fact of course) if a flywheel bolt or bolts came off with little to no effort. Many bad things could have happened.

Did you use heavy duty hi-strength Loctite when they were installed? Perhaps you didn't install them but you can check to see if there was any residue on the bolts that would indicate some one else used or didn't use it. Not torqueing them to spec could have also contributed to the looseness of the bolts.

[Reptoid Overlords]

As of now, the transmission and flywheel are out of the car, awaiting clutch parts/flywheel resurfacing. Its the 1st time I have pulled the trans/flywheel out.

I did not notice any loctite or any other residue on the flywheel bolts.

They weren't so loose that they required zero effort to back out, but the amount of force required to back them out is concurrent with the theory that they weren't torqued to the proper spec..at least from my relatively inexperienced perspective with that part of the car.

The transmission removal process went quite smoothly. I took my time, used a floor transmission jack and made sure not to jolt/force anything on removal.

I was trying to think of how I might have,even though I thought I was being careful, damaged an internal engine component. But, as I said before, it does turn normal in the proper direction of operation.

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[Dave WM]

I did not notice any Loctite on mine, I used air on mine so not sure just how hard they would have been to get out. I did us Loctite (blue not red) to put them back in and torqued to 100flbs.

while you have it out take a look for leakage around rear main and side seals. good time to replace the rear main (sides can be done too but don't have to have the trans off for that). Also make sure to use a new pilot bushing. Use 2 long bolts with heads cut off as pilot bolts when reinstalling, makes it go a lot easier. after sliding trans on you can remove the long guide bolts and replace with reg bolts.

Edited January 25, 2018 by Dave WM

[Zed Head]

2 hours ago, Reptoid Overlords said:

It will spin in the normal direction of operation. Of course, I'm not going to try and spin it backwards to see.

Removing the bolts would turn the engine in the normal direction.  Tightening will be backward.  Posted a picture I stole from Hemmings, showing fan direction.

Are you asking about two things, how loose the bolts were and, apparently, the fact that the engine doesn't turn?  Once you break the bolts loose it won't take much to turn them.

Pretty sure that my flywheel had never been removed, and it had what looked like threadlocker on the the bolts.  I made a flywheel locker from a metal bracket I had lying around.

[EuroDat]

Personally I would not use high strength loctite because it will require heat to release the bolts.

All I do is clean all the threads, lightly oil the threads and use a tension wrench to tighten them to spec. Dry threads have more resistance and will not tighten down as far ss lightly oiled threads.

[Reptoid Overlords]

I got turned around, laying on my back, looking up at the rear of the engine. Should've thought it through before posting.

 

Anyhow, I haven't spun the engine in any direction, I rotated the engine about 1/2 inch or so when the flywheel was still on..this would have been the wrong direction.

 

When I get home, I will turn the engine in the direction of operation from the crank pulley and see how it feels.

 

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Edit: To clarify, the primary question I'm asking is: why was I able to hand ratchet the flywheel bolts out without anything keeping the engine from turning.

 

Now that I have the orientation of proper direction, I should be able to turn the engine by hand with a breaker bar using the crank pulley.

[EuroDat]

1 hour ago, Reptoid Overlords said:

Edit: To clarify, the primary question I'm asking is: why was I able to hand ratchet the flywheel bolts out without anything keeping the engine from turning.

Probably the PO didn't tighten the bolts to the specified torque and they loosened over time. There is a reason for a certain tension on bolts.

When the flywheel and crankshaft heat up, the bolts can expand and become a fraction longer. In this situation the flywheel can move and the bolts can loosen further over time. The tension Nissan specifies is calculated the prevent this from happening.

[Dave WM]

I am sure you already know this, but I think the bolts should be tightened in a star pattern as well. I started at about 25ft lbs and works up in 25 increments. You need to figure a good way to hold the fly still while using the torque wrench. Did you check for leakage around that seal? its pretty easy to see, remove the cover to examine the side seals too. I had a persistent leak at the back of the pan, think about 1/2 rear main and 1/2 side seals (you could see evidence of leakage from both areas). It looks like a pan leak in the rear.

Edited January 25, 2018 by Dave WM

[Reptoid Overlords]

Thanks for all the good information. I will most certainly be following the bolt tightening pattern and torque specification prescribed in the FSM.

The rear main seal does not appear to be leaking, but I will take the advice and replace it anyway.

From research, it seems I'll have to pay close attention to ensure it seats properly.

From the looks of it, now would be a good time to replace the oil pan gasket as well.

I will most likely end up replacing all of the suggested seals.

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