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engine rotates clockwise if looking at the crank pulley
 

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Hi, that rotation is blocked when i put a wrench of the crankshaft pulley...
question then remains what causes this blocking...
there is known problem sometimes belt cover due to age gets brittle and breaks apart. worth checking maybe piece got stuck on cambelt and prevents rotation clockwise.
 

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Discussion Starter · #44 ·
there is known problem sometimes belt cover due to age gets brittle and breaks apart. worth checking maybe piece got stuck on cambelt and prevents rotation clockwise.
The Belt cover looks fine when inspecting this
 

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Discussion Starter · #45 ·
Could it be possible the crankshaft is mechanically blocked by the gearbox?
Even when the selected gear is N
 

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Could it be possible the crankshaft is mechanically blocked by the gearbox?
Even when the selected gear is N
unlikely. if you can turn crankshaft one way, but not another gearbox should be in N. if it's stuck in gear you shouldn't be able to turn engine one or another way.
of course depends how much can you turn crankshaft by hand. is it 90 degrees, 180 or full revolution?
 

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Discussion Starter · #47 ·
unlikely. if you can turn crankshaft one way, but not another gearbox should be in N. if it's stuck in gear you shouldn't be able to turn engine one or another way.
of course depends how much can you turn crankshaft by hand. is it 90 degrees, 180 or full revolution?
Ok thanks, i will start testing how much the crankshaft can be turned by hand counter clockwise
 

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Did you pull the spark plugs and see if one of the cylinders is full of gas? Can you let release the E brake and roll it forward and backwards. If it is truly in N you should be able to do that. At this point I would probably give up and head to dealers. Sounds like something beyond a simple home shop diagnostic. This is the first time I have heard of something like this on a 4C and many of us including me do put our cars in Winter hibernation. In my case I am in Michigan and a 4C makes a lousy snow plow ;-)
 

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Discussion Starter · #52 ·
Did you pull the spark plugs and see if one of the cylinders is full of gas? Can you let release the E brake and roll it forward and backwards. If it is truly in N you should be able to do that. At this point I would probably give up and head to dealers. Sounds like something beyond a simple home shop diagnostic. This is the first time I have heard of something like this on a 4C and many of us including me do put our cars in Winter hibernation. In my case I am in Michigan and a 4C makes a lousy snow plow ;-)
Hi, the car is on the car lift now
But i can free spin the rear wheels
What do you mean with E brake?
 

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Discussion Starter · #54 ·
OBD Diagnostics performed;
No error present in Engine/Body etc..

Focused on OBD of Gearbox, several Actuators can be tested here;
1-Pump motor
2-Clutch solenoid valve (even gears)
3-Clutch solenoid valve (odd gears)
4-Range selection solenoid valve
5-Engagement solenoid valve (1st/4th/5th/6th)
6-Engagement solenoid valve (3rd/2nd/Reverse)
7-Lock-up solenoid

Testing these in order above gives some results;
1-Cannot be executed due to incorrect conditions to run this test
2-Runs successfully
3-Runs successfully, but generates an error P293E-62-Clutch system
this is reset after ignition off/on
error can be reset
4-Runs successfully
5-Runs successfully, 2 errors are generated P2905-94-mechanical problem, P2914-86-Torque requested by driver
this is reset after ignition off/on
error can be reset

will update this list soon
 

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How do I check this, if this is engaged or not?
hill-start has no effect when ignition is off.
if engine still rotates only one way most likely there is something broken of and gets stuck turning it other way. you will need to inspect timing belt and what's happening under valve cover
 

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How do I check this, if this is engaged or not?
If your rear wheels don't turn the e-brake is engaged. Nothing to do with the engine not cranking over. Just ensure you're in neutral with your foot firmly on the foot brake when you turn the ignition key.
 

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Discussion Starter · #59 ·
hill-start has no effect when ignition is off.
if engine still rotates only one way most likely there is something broken of and gets stuck turning it other way. you will need to inspect timing belt and what's happening under valve cover
Will open the valve cover to double check
Besides this, will remove the crankshaft wheel and the belt driving AC and generator, to fully test if the blocking is caused by Crankshaft or one of the Camshafts, at least then i know...
 

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As an old GTV-6 owner this sound like the timing belt has skipped a tooth or two... I remember many years ago helping a friend do the belt on his 12V 164... He didn't remove the cam cover to access the timing marks, he just made some paint marks on the engine because he found an "easier" way to do the belt on-line... Anyway, when he finally listened to me and tried to roll the engine over by hand it wouldn't turn very far before stopping but he could roll it 360 degrees backwards because the way the slack in the belt let the cams/valves and crank mesh. I told him not to make a habit of rolling that engine backwards but it really isn't as bad as everyone thinks if the plugs are out.

DON'T EVER ROLL A BUSSO V-6 BACKWARD WITH THE PLUGS IN, YOU WILL JUMP THE TIMING BELT OUT OF TIME! BAD THINGS WILL THEN HAPPEN IF YOU TRY TO START IT.

Having just done the timing belt and water pump (early April) on my 4C IMO turning the engine backwards with the plugs out isn't going to be an issue, there is plenty of contact around the pulleys and the timing belt tensioner will take care of the slack but I wouldn't make it a habit either.

Still, it is interesting that the engine will not turn the correct way at all. If the clutch were stuck or the engine hydro-locked it wouldn't turn in either direction... What comes to mind is that something broke almost immediately when you tried to start it the first time and now prevents the engine from rotating. But one would think if the engine will rotate backwards it should rotate forwards at least to the point where the damage causes interference.

I went back and re-read this entire post and IMO when you tried to start the car the first time something inside the engine broke. I don't know or why the engine will rotate backwards but not forwards but I'd guess that your manual manipulation of the crankshaft has moved the broken pieces around such that the engine will roll one way but not the other.

Just a guess is that a valve keeper failed and the valve dropped down into the cylinder. It hasn't fallen completely out of the guide but it probably isn't totally straight either. My thought is that when you try to spin the engine with the starter motor the valve locks the engine in place but turning backwards by hand is slow and jerky enough to push the valve back up into the guide. Forward is probably blocked by the damage to the valve and piston causing the broken parts to shift ever so slightly and restricting the engine's rotation.

I'd say go to Harbor Freight and buy one of their $60.00 borescopes and have look down into each of the cylinders. You may not like what you see...
 
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