Head gasket job, trying to clean pistons but crank will not turn

Joined
Jun 13, 2014
Messages
111
Location
The Colony, TX
Hi, all, I'm in the middle of a head gasket job. The head is off, and I just finished cleaning the block surface, as well as de-carboning the tops of pistons 1 and 6. I began turning the crank clockwise and got to about a quarter of a revolution and I cannot rotate it anymore. It just won't move. I then rotated it back to TDC counter-clockwise without any problem. When I try to rotate clockwise again, it won't budge. Kinda concerned here. Am I missing something simple? Like the tranny needs to be in Neutral instead of Park? Or, something terrible like a hydro-lock?
 
Joined
Jun 13, 2014
Messages
111
Location
The Colony, TX
Chock the wheels and put the transfer case in nuetral. Belt off the drive line and ac compressor.
The AC belt is now loose. Still stuck. When the head was on and I was checking/adjusting my timing I don't recall ever putting it in neutral, and was able to turn it by hand. With the battery out, is there a way to put it in neutral?
 
Joined
Apr 24, 2021
Messages
21
Location
Houston
The AC belt is now loose. Still stuck. When the head was on and I was checking/adjusting my timing I don't recall ever putting it in neutral, and was able to turn it by hand. With the battery out, is there a way to put it in neutral?
I think theres a button on near the gear selector that lets you change gears while the battery is disconnected. Key in the ignition for that I think.

I'm trying to imagine what else could be the issue.
 
Joined
Sep 30, 2014
Messages
573
Hey mate, can't be hydrolocked with the head off. More than likely the timing chain has got stuck/binded up preventing it from turning...
 
Joined
May 18, 2021
Messages
22
Location
Corpus Christi, Texas
You should be able to turn the key to the run position. Press on the brake, Put transmission in neutral then put your transfer case in neutral as well. That will isolate binding in the drive train if it is that.
 
Joined
Jun 13, 2014
Messages
111
Location
The Colony, TX
You should be able to turn the key to the run position. Press on the brake, Put transmission in neutral then put your transfer case in neutral as well. That will isolate binding in the drive train if it is that.
I was able to put both the tranny and tcase in neutral, but still cannot turn the crank.
 
Joined
Nov 13, 2002
Messages
625
Location
The Saratoga slums, CA
^^^ This. Your chain is dropping down as you try to rotate the crank. As it moves, slack in the chain will cause it to not align with the sprocket gear at the crank. There is narrow clearance between the sprocket and an oil splash on the bottom of the timing chain cover. Don't force things otherwise you may damage the aluminum timing cover or the sprocket gear.
If you read the factory service manual, one of the first things that they tell you to do before removing the head is to zip tie the timing chain in place to prevent it from dropping down - for the very reason that you have discovered. In addition, there is a bright alignment link on the chain that is supposed to match up with a mark on the top timing gear. If you have created slack in your chain by rotating the engine in a reverse direction, you run the risk of skipping a tooth and not aligning that timing mark with the crank.
Take a look here for an example of what can happen:
1994 1fz-fe Timing chain installation, alignment and timing questions. - https://forum.ih8mud.com/threads/1994-1fz-fe-timing-chain-installation-alignment-and-timing-questions.789240/
 
Joined
Jun 13, 2014
Messages
111
Location
The Colony, TX
Thank you all for the replies. I believe you are all correct about the timing chain. I have now tried holding the sprocket and chain up and tight and tried turning the crank by hand, but no movement on the crank. Hmmm, I think I see where this is going now. What are my options here? Is my only path here to pull the timing cover and fix down below?


FF51E161-4F2D-43BE-8E9D-9DE8C5AFCD8E_1_105_c.jpeg
 
Joined
May 13, 2012
Messages
84
Location
Seattle, WA/ Jacksonville, OR
Adding to what everyone else has said.

The chain has got to be bound up in there. Cut the zip ties and also try reversing you direction a small amount while holding the chain taut. It sounds like a link is bound up on the crank. Trans/ t case have no affect on this. Don't bother putting things in neutral.
 
Joined
Nov 13, 2002
Messages
625
Location
The Saratoga slums, CA
just make sure that you double check the timing when its going back together, dont want to be off a link and figure that out when your all wrapped up
Yes, listen to @bigredmachine .
Glad you got the chain freed up!
You are not quite out of the woods yet. You need to reset the engine to TDC on the compression stroke and then check the alignment of the links with the timing gear. The bright link should be aligned with the mark on the camshaft timing gear. That mark should be at the top of the camshaft gear at the 12 o'clock position. If the gear is clocked to one side or another, you may have skipped a link down at the crankshaft gear. Since you don't have the timing cover removed, you can't visually confirm that the second bright link is aligned properly down at the crankshaft gear. Make sure everything is aligned before you try to start the engine up the first time.

timing gear1.jpg

.
timing gear2.jpg

Sounds like you've got it. Just double check everything.
Good Luck!
 

Users who are viewing this thread

Top Bottom