Advice Needed - Engine Not Turning

[Dat73z]

Hi guys, 

 

Looking for advice to turn my motor over which doesn't want to turn by hand with the spark plugs out. Also some pictures to detail some of the steps which I took in case I second guessed something. Everything torqued to FSM spec with Snap On digital torque wrench. 

 

So here is the short of the long in basic sequence of events over the last couple of weeks: 

 

Engine side (L24 Block)

 

1) Installed new rear main seal + front main seal + timing cover gaskets - motor turns over fine

2) Installed AZC oil pan + felpro cork/rubber gasket - motor turns over fine

3) Installed 240mm chromoly flywheel + new OEM 2+2/turbo bolts (these are thinner than stock 240) + pilot bushing - motor turns over fine

4) Installed 240mm clutch + PP (9 bolt) - motor turns over fine

5) Torqued everything down to FSM spec + blue loctite including crank pulley bolt since I could lock the flywheel at this point easily - motor turns over fine

 

Transmission side (280zx 5 Speed)

 

6) Installed all new gaskets and seals - transmission rotates fine 

7) Installed short turbo throwout bearing collar and new bearing + clutch arm onto transmission - transmission rotates fine

 

Assembly

 

8) Installed transmission onto motor along with new 280zx starter and clutch master + slave cylinders. Clutch system is bone dry right now. Did not need to force the transmission on, just lined up the splines to slip on then torque down.

 

After (8) engine does not want to rotate by hand in neutral from the crank pulley bolt and did not want to force it with a breaker bar so left it at that. 

 

Am I missing anything here? I should also mention that when I had the front timing cover off I'm pretty sure that I did not bump anything out of alignment in the process. I'm thinking I should pull the transmission and backtrack, but literally just got the header + intake on there and clearances are pretty tight. Have installed many a clutch, transmission, etc. over the years but have never had this issue. 

 

Thanks in advance guys, just trying to backtrack and figure out what could be causing the no turn 

 

Edit: A couple of last thoughts and points: 

 

1) Both engine and transmission are bone dry right now and has been for a couple of months. Motor was not burning anything. Was running but water pump blew up and every seal on the motor was leaking along with 4 speed going out. Clutch was soaked from both ends due to rear main and transmission seal failures - refresh time. Last time I turned the motor by hand was 3 or 4 weeks ago? I shot some penetrating fluid down each cylinder a day ago when I discovered this (was trying to set motor to TDC to adjust valves). 

 

2) Should I fill the clutch system with fluid and try pumping the clutch a couple of times to see if anything frees up? No idea, just trying to avoid pulling everything apart again. I'm running out of beer and patience. 

Edited July 1, 2015 by Dat73z

[NewZed]

Can't remember exactly where I saw it, two places I think, but it was very recently: check that you didn't use an overlong bolt to install the slave cylinder.  Apparently it's possible to jam the bolt end in to the pressure plate cover that way.

[Dat73z]

Thanks NewZed, I'm going to give that a shot later today to see if I can narrow this down. I'm pretty sure I used the OEM 240z or 280zx slave cylinder bolts based on the picture above, but I recall recently reading about that potential issue as well. 

[beermanpete]

Perhaps the transmission got into two gears at once? Can you rotate the propellor shaft (drive shaft) by hand?

[dexter72]

Try back tracking and remove the starter and see if it turns. Possible starter problem, starter bolt problem.. 

 

Then try loosening up the trans bolts and see if the engine will turn... Just a thought, can you move the clutch fork back and forth ??.. Possible clutch part issue...

[Dat73z]

So was not the clutch slave bolts. Also filled and bled the clutch system, and set up my phone to record. Clutch fork movement is superb, no binding and functioning as intended. Pedal feels great, a little more effort than the factory 240z, but everything in the car was leaking before. Engine still won't turn. 

 

Going to slide in the prop shaft and attempt to rotate trans in neutral then onto starter. Will report back with results. 

 

Thanks for the help guys. 

Edited July 1, 2015 by Dat73z

[Dat73z]

Did not even need to slide prop shaft in, transmission output shaft rotates freely in neutral between my fingers. 

 

Removed starter, flywheel visible still no dice, engine stuck. 

 

So I suppose this leaves me with pull the transmission and inspect? 

[NewZed]

You said that the clutch works.  Not sure how you tested it, but if you have someone press the pedal while you try to turn the engine that should tell you if the transmission input shaft is bound up.  Unless the input shaft is jammed inside the crankshaft pilot bearing, disengaging the clutch should leave you with the engine only.  If it turns with the clutch pedal down, bit not with it up, then the input shaft is stopping the movement.

 

The transmission output shaft should turn while in gear also, if the clutch is disengaged, since it's the engine and the transmission that are being engaged and disengaged.  Except for the pilot bushing. 

 

In short, a working clutch system should separate the potential problem areas. 

 

 

 

Edited - spelling

Edited July 1, 2015 by NewZed

[Dat73z]

Ah, that makes sense. My housemate just got home so I'm going to have her hop in the car and depress the clutch pedal while I attempt to turn the engine. Will report back here shortly. 

 

In my previous post I used my cell phone video to record the clutch slave moving the clutch fork fully thus depressing the pressure plate. Have not attempted to spin the motor yet with the transmission in neutral and someone depressing the clutch. 

Edited July 1, 2015 by Dat73z

[Dat73z]

Alright so with the transmission in neutral and my housemate fully depressing the clutch the engine is completely locked up. 

 

Going to pull the transmission tonight and see what the heck is going on! Will report back with results. 

 

I checked for rotation every step of the way since I was mixing and matching parts EXCEPT right before I bolted my header and manifold on   . Got too excited. 

 

If anyone has anymore thoughts please chime in, really appreciate it. 

Edited July 1, 2015 by Dat73z

[NewZed]

A too-long bolt in the thermostat housing will pin the timing chain guide to the chain and sprocket.  The threaded hole is open on the back.  Not uncommon.

 

Don't forget the belted accessories also.  Alternator, AC compressor, water pump and fan.

Edited July 1, 2015 by NewZed

[Dat73z]

Thanks, just took a quick peek at the Tstat housing and bolt looks to be the correct length. Picture attached. 

 

Only running alternator belt, but it's on there finger tight (e.g. no tension) at the moment. 

[seattlejester]

Without reading through all the posts yet, I want to say. Timing chain tensioner? If you did the FMS, did you remember to keep the timing chain taught and all that?

 

Also to do the FMS you would have had to break the crank pulley loose, how did you break it loose and tension it? Possible that you may have skipped a few teeth or something. 

 

Edit: No oil in the tranny or engine? I hope you didn't score anything by turning it by hand, but I would add some. A little lubrication goes a long way and if you are bone dry then that alone could cause difficulties.

 

Something that is highly unlikely, but can you get a bit of movement with turning the engine every so slightly backwards? If you get traction in that direction then it is possible something dropped into the cylinder and is actually physically preventing you from turning the motor. This is a really unlikely scenario though, but something to look into.

Edited July 2, 2015 by seattlejester

[Dat73z]

Just dropped the oil pump to check the timing chain tensioner, hard to make out in the photo but it looks tight on the alternator side of the motor to me. Slack side of the chain has some slack as well. 

 

Not sure about keeping the chain tight, was just careful to not bump anything out of place with the front timing cover off. Here is how I went about replacing the seals at the front of the motor: 

 

1) Drop oil pan 

2) Impact gun + thread on pulley puller to remove crank pulley bolt + washer

3) Remove front timing cover

4) Replace crank snout seal

5) Bolt front timing cover back in place with new gaskets

6) Bolt in AZC oil pan with new gasket

7) Lock flywheel and torque crank pulley bolt + washer back to ~100 ft-lb with loctite blue

 

Also checked if the motor would turn CCW. Set torque wrench to 50ish ft-lb and attempted but no dice. 

 

Yeah, I drained all of the fluids from the motor due to realizing my water pump was vomiting out of the weep hole something furious. No overheating, caught it right at failure. In the process I realized that the block freeze plugs were starting to go along with everything else. This was maybe a couple of months ago (I'm a slacker), but now on the tail end of the refresh process so probably not completely bone dry but not lubricated as in I ran the car yesterday. 

Edited July 2, 2015 by Dat73z

[Dat73z]

I should also note that prior to replacing the front timing chain cover I checked the chain stretch per FSM by rotating the engine by hand to the marks on the cam gear. Everything was in spec. This was like a month or so ago. 

 

Am going to start pulling everything apart here after this beer. I am completely stumped! 

 

Only things I can think of are: 

 

1) Engine massively seized after sitting for a couple of weeks (maybe unlikely?)

2) Something binding somewhere (more likely, but what?!)

[NewZed]

 

Not sure about keeping the chain tight, was just careful to not bump anything out of place with the front timing cover off. Here is how I went about replacing the seals at the front of the motor: 

 

1) Drop oil pan 

2) Impact gun + thread on pulley puller to remove crank pulley bolt + washer

3) Remove front timing cover

4) Replace crank snout seal

5) Bolt front timing cover back in place with new gaskets

6) Bolt in AZC oil pan with new gasket

7) Lock flywheel and torque crank pulley bolt + washer back to ~100 ft-lb with loctite blue

 

Also checked if the motor would turn CCW. Set torque wrench to 50ish ft-lb and attempted but no dice. 

 

 

If I'm reading right, the actions above are the last significant actions between when the crankshaft would turn and now, when it doesn't.

 

Seems like the damper (I think you're calling it the crank pulley) reinstallation is the most likely cause.  Maybe you jammed the woodruff key past its keyway in to whatever is behind it (I don't know what's behind it, I think more keys and keyways).  100 ft-lbs can do some jamming.  Might try loosening the damper bolt or just removing the damper, then using the propeller shaft to rotate the engine.  Put the car in gear and roll it.  Inspect the woodruff key slots for damage first, might have to be fixed anyway.

[Dat73z]

Going to go zip off the crank pulley now and take a look. I do recall inspecting the woodruff key and channel when I did the front timing cover, everything looked great. Pulley went on smoothly as well. I turned it in by hand first before applying torque. 

[NewZed]

Could also be that somehow you've jammed the damper up against the timing cover. 

[Dat73z]

So just inspected the timing cover again and it's definitely not jammed. Also I do recall turning the motor over by hand after the crank pulley torque/install. Attached a pic from inspection just now. Going to start pulling the transmission. Not an ideal scenario, but usually it's spend an hour in the garage listening to music while drinking beer and 20-30 mins to actually pull a trans. Will report back soon. 

[Dat73z]

Alright so I pulled the transmission earlier and everything looks great. Motor is still absolutely stuck. Torque wrench set at 100 ft-lb on the crank snout will not turn it. 

 

Going to throw on the new OEM trans mount and powdercoated bracket then start tearing back into the motor.