Crankshaft Bolt
#21
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In https://www.yotatech.com/forums/f116...h-3vze-137934/ I describe a method to reach 181 ft-lbs using a torque wrench that only reaches 150 ft-lbs.
#24
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I've never tried it; be sure to leave some rope hanging so you can get it back out!
Note that most of these alternate methods don't help much when you are tightening the bolt (with the rope, you'd need to pull it out, get the piston past TDC, then put the rope back in. I'm not sure how the "starter" method works to tighten.)
#27
i just put tming belt in my 3.0 and it appears someone had the crank bolt out recently becauseit was not very tight. well anyway whe i got it all apart i found that the crankshaft gear was allongated where the keyway goes and the keyway was all messed up. this effected the timing alot. in my opinion if you are going to do your own work a torque wrench should be at the top of ur list not very expensive and eliminates all doubt. btw 181ft/lbs is the correct torque i believe
#28
Registered User
Thread Starter
Looks like I should go get me one.
i just put tming belt in my 3.0 and it appears someone had the crank bolt out recently becauseit was not very tight. well anyway whe i got it all apart i found that the crankshaft gear was allongated where the keyway goes and the keyway was all messed up. this effected the timing alot. in my opinion if you are going to do your own work a torque wrench should be at the top of ur list not very expensive and eliminates all doubt. btw 181ft/lbs is the correct torque i believe
#30
Registered User
I just changed my timing belt for the third time and used the bump the starter method to break loose the crank bolt. It worked well, but you have to be careful how you position the breaker bar since it will develop a LOT of force. I used an impact socket.
Since the starter rotates the crankshaft in the unscrew-the-bolt direction, not sure how that could be used to tighten it ??? But anyway, no, even if it did turn the crank in the opposite direction it would not be possible to trust it to get anywhere near the right torque.
My torque wrench also only goes to 150 ft lbs, so I tighten the bolt to that amount, then swapped out the torque wrench for a breaker bar with pipe extension and then tightened it approximately 30 lbs more by feel. That's not something I'd recommend, necessarily, but I've gotten away with it for 3 belt changes. 'Course I have been wrenching for some 37 years now, so have a fairly good feel for torque... To be safe I'd borrow or rent a torque wrench that DOES go up to 181 - Autozone lends a lot of tools - they might have one. Re: the method mentioned in an earlier post, I don't think Hookes Law would apply since I believe strain increase is exponential, not linear, as a fastener gets tighter. I don't think the bolt would travel as far to go from 150 to 180 ft lbs as it does from 130 to 150, but that distance would at least give you an upper limit of movement - a distance you wouldn't want to exceed. It probably wouldn't be far off, tho.
To hold the pulley for torquing the crank bolt I make a strap wrench out of the old timing belt. It does work well, but there are lots of other fabbed tools that work well too. Here are a bunch of them:
https://www.yotatech.com/51094700-post10.html
https://www.yotatech.com/forums/f116...e-tool-191312/
https://www.yotatech.com/forums/f116...lt-job-122420/
https://www.yotatech.com/forums/f116...l-tool-186081/
https://www.yotatech.com/forums/f116...h-3vze-137934/
https://www.yotatech.com/forums/f116...ol-sst-161133/
By the way I see you have an earlier design timing belt idler arrangement like on my truck. Since the online manuals are all for the later trucks that have a tensioner, here's the technique for tensioning the belt with the older design, from an older post:
Since the starter rotates the crankshaft in the unscrew-the-bolt direction, not sure how that could be used to tighten it ??? But anyway, no, even if it did turn the crank in the opposite direction it would not be possible to trust it to get anywhere near the right torque.
My torque wrench also only goes to 150 ft lbs, so I tighten the bolt to that amount, then swapped out the torque wrench for a breaker bar with pipe extension and then tightened it approximately 30 lbs more by feel. That's not something I'd recommend, necessarily, but I've gotten away with it for 3 belt changes. 'Course I have been wrenching for some 37 years now, so have a fairly good feel for torque... To be safe I'd borrow or rent a torque wrench that DOES go up to 181 - Autozone lends a lot of tools - they might have one. Re: the method mentioned in an earlier post, I don't think Hookes Law would apply since I believe strain increase is exponential, not linear, as a fastener gets tighter. I don't think the bolt would travel as far to go from 150 to 180 ft lbs as it does from 130 to 150, but that distance would at least give you an upper limit of movement - a distance you wouldn't want to exceed. It probably wouldn't be far off, tho.
To hold the pulley for torquing the crank bolt I make a strap wrench out of the old timing belt. It does work well, but there are lots of other fabbed tools that work well too. Here are a bunch of them:
https://www.yotatech.com/51094700-post10.html
https://www.yotatech.com/forums/f116...e-tool-191312/
https://www.yotatech.com/forums/f116...lt-job-122420/
https://www.yotatech.com/forums/f116...l-tool-186081/
https://www.yotatech.com/forums/f116...h-3vze-137934/
https://www.yotatech.com/forums/f116...ol-sst-161133/
By the way I see you have an earlier design timing belt idler arrangement like on my truck. Since the online manuals are all for the later trucks that have a tensioner, here's the technique for tensioning the belt with the older design, from an older post:
Replacing the Timing Belt on the 3VZE. I recommend following the factory manual but be aware you do NOT have to remove the cam pulleys to change the timing belt. The fsm is confusing on that point. I find this technique works well for mounting the belt: position the driver side cam pulley exactly on the mark. Position the passenger cam pulley a half tooth clockwise of the mark (as viewed from the front of the vehicle looking back). Position the crankshaft pulley a half tooth counter-clockwise. Mount the lower idler pulley (the tensioner) but tighten it as much out of the way as possible (against the tension spring).
Then place belt around driver cam pulley (if using a toyota belt there will be timing marks on the belt). Then route belt under upper idler and around passenger cam pulley. Then position passenger cam pulley exactly on the mark - the belt should now have no slackness between the cam pulleys. Route belt around water pump pulley and then around crankshaft pulley. Position crankshaft pulley exactly on mark - there should now be no slackness between driver cam, water pump and crank pulley. Route belt around tensioner pulley, and loosen the adjustment bolt so pulley is free to press against and tension the belt.
92-95 have a slightly different idler pulley design with a tensioner, which the 88-91 engines lack. Follow fsm procedure for tensioning belt on the newer motors. To tension the belt on the earlier design, attach lower idler & spring with mounting bolt not fully tight so pulley can move, rotate crankshaft TDC to TDC two full revolutions clockwise (viewed from front looking back) so the spring can tension belt, then torque lower idler to 27 ft lbs, leaving spring in place. Check that the marks on both cam pulleys align with the marks on the backplate. On my veezy, the cam marks do not exactly align with the backplate marks when crank at TDC, but when in the right position the marked cam tooth is closer to the backplate mark than any other tooth is. (If you used a Toyota belt with timing marks, those will have traveled.)
Then place belt around driver cam pulley (if using a toyota belt there will be timing marks on the belt). Then route belt under upper idler and around passenger cam pulley. Then position passenger cam pulley exactly on the mark - the belt should now have no slackness between the cam pulleys. Route belt around water pump pulley and then around crankshaft pulley. Position crankshaft pulley exactly on mark - there should now be no slackness between driver cam, water pump and crank pulley. Route belt around tensioner pulley, and loosen the adjustment bolt so pulley is free to press against and tension the belt.
92-95 have a slightly different idler pulley design with a tensioner, which the 88-91 engines lack. Follow fsm procedure for tensioning belt on the newer motors. To tension the belt on the earlier design, attach lower idler & spring with mounting bolt not fully tight so pulley can move, rotate crankshaft TDC to TDC two full revolutions clockwise (viewed from front looking back) so the spring can tension belt, then torque lower idler to 27 ft lbs, leaving spring in place. Check that the marks on both cam pulleys align with the marks on the backplate. On my veezy, the cam marks do not exactly align with the backplate marks when crank at TDC, but when in the right position the marked cam tooth is closer to the backplate mark than any other tooth is. (If you used a Toyota belt with timing marks, those will have traveled.)
Last edited by sb5walker; 09-28-2010 at 11:04 AM.
#31
Registered User
Lol....the FSM says that? I've never removed the cam pulleys to change a timing belt. Funny.
That method sounds much like what TNRabbit and I have discussed in the distant past.
Great post, btw!
That method sounds much like what TNRabbit and I have discussed in the distant past.
Great post, btw!
#32
Registered User
Thread Starter
Below is quote from sb5walker,
"Since the starter rotates the crankshaft in the unscrew-the-bolt direction, not sure how that could be used to tighten it ???"
To loosen the crank bolt I put 30 inch pipe on ratchet and put pipe under the frame on the passenger side. Then bump starter.
To tighten you reverse the procedure, put pipe on top of driver side framerail or on top of leaf pack on drivers side. Then bump starter.
Thanks for the FSM quotations.
#33
Registered User
That dog doesn't hunt. In both cases, the starter is turning the crank in the same direction (clockwise as viewed from front looking back) which - if you have something on the bolt to prevent it from moving, will UNscrew the bolt. Bracing under the passenger frame or on top of driver side - both are bracing in same direction - preventing bolt from turning clockwise while the starter turns the crank clockwise. To tighten that bolt using that technique, the starter would have to rotate the engine in the opposite direction - not going to happen.
#34
Registered User
#35
Registered User
I wonder if putting a pipe wrench on the yoke of the rear drive shaft and blocking it against the frame would keep the motor from turning?<<< Torque wrench time!!>>>
#36
Registered User
Thread Starter
Thanks (I think).....
Just put a timing light on it this morning. It was set counterclockwise all the way - 2* to 4* ATDC - and made the idle 450-500 RPMS. Took it up to 10* BTDC and watched the idle really smooth out at 800-850 RPMS.
Will drive it some at this setting even though FSM says 8* BTDC is normal.
180ft-lb torque wrench is coming.
Just put a timing light on it this morning. It was set counterclockwise all the way - 2* to 4* ATDC - and made the idle 450-500 RPMS. Took it up to 10* BTDC and watched the idle really smooth out at 800-850 RPMS.
Will drive it some at this setting even though FSM says 8* BTDC is normal.
180ft-lb torque wrench is coming.
#37
YotaTech Milestone-Two Millionth Post
Thanks (I think).....
Just put a timing light on it this morning. It was set counterclockwise all the way - 2* to 4* ATDC - and made the idle 450-500 RPMS. Took it up to 10* BTDC and watched the idle really smooth out at 800-850 RPMS.
Will drive it some at this setting even though FSM says 8* BTDC is normal.
180ft-lb torque wrench is coming.
Just put a timing light on it this morning. It was set counterclockwise all the way - 2* to 4* ATDC - and made the idle 450-500 RPMS. Took it up to 10* BTDC and watched the idle really smooth out at 800-850 RPMS.
Will drive it some at this setting even though FSM says 8* BTDC is normal.
180ft-lb torque wrench is coming.
#38
Registered User
Thanks (I think).....
Just put a timing light on it this morning. It was set counterclockwise all the way - 2* to 4* ATDC - and made the idle 450-500 RPMS. Took it up to 10* BTDC and watched the idle really smooth out at 800-850 RPMS.
Will drive it some at this setting even though FSM says 8* BTDC is normal.
180ft-lb torque wrench is coming.
Just put a timing light on it this morning. It was set counterclockwise all the way - 2* to 4* ATDC - and made the idle 450-500 RPMS. Took it up to 10* BTDC and watched the idle really smooth out at 800-850 RPMS.
Will drive it some at this setting even though FSM says 8* BTDC is normal.
180ft-lb torque wrench is coming.
Things like getting the crank bolt tight enough you never want to second guess. You want to be positive. Even if the engine would turn in the other direction, you can't be sure it's tight enough without gauging it......unless you have a very accurate air wrench where you can set the torque. Even then, you should check it by hand. There is still room for error.
Seriously.......see if you can rent a torque wrench and save yourself some money, man. Unless money's not really an object?? A torque wrench does always come in real handy.
#39
Registered User
BTW, *10 won't hurt anything, as you probably already know. But, there could be something just a tad wonky with something else on the engine that makes it run better at 10* as opposed to 8*. Keep an eye on the mileage and power after you've driven it around a bit and the ECU's had time to make adjustments. If you're not happy with everything after that, maybe some exploratory troubleshooting would be in order.
Good luck, Phil.
Good luck, Phil.
#40
Registered User
Thread Starter
I just went right for the 10* BTDC. Apparently it's never been timed correctly.
I will check about renting the tool needed to achieve 181 on the torque meter.
I will check about renting the tool needed to achieve 181 on the torque meter.