how do you tighten crank bolt to 270 ft. lb.??

Sun Feb 10, 2008 6:28 am

Im putting crank pulley back on after motor and tranny install. Motor and tranny are installed havent put no fluids in engine or cooling system or tranny yet, im trying to tighten crank bolt to 270 ft.lb. , but how do you stop the pulley from turning? My car is up on all 4 jackstands still so no tites on ground.I thought i could put it in gear and it wouldnt turn,but that didnt work,just pulley turned not back tires or drive shaft!! im confused!! please help. !!!!! SUBZERO

Post by **Q45tech** » Sun Feb 10, 2008 6:51 am

Special Chain wrench around crank pulley long handle wedged against frame.Careful don't bend or break a ridge off crank pulley.

Depending on arm strength [we have a complete gym at T3] you may have to adapt torque wrench with extension pipe.

Too little like 180-240 lb/ft can cause serious oil pressure problem!!!!!!!!!!!!

Post by **Q451990** » Sun Feb 10, 2008 6:52 am

The typical method is to use a chain wrench wrapped around the pulley with some sort of protection (old belt) to keep from damaging the ribs - and brace it against something solid... like those crossmembers that run at a 45 degree angle. I certainly wouldn't use the parking pawl in the transmission to hold up to that kind of torque!

Heath

Sun Feb 10, 2008 7:20 am

Thanks for the help,ive heard of the chain wrench,i thought there might be another trick that would work,i dont have access to a chain wrench! i didnt think the 270 would be too much for parking prawl on tranny,i guess so!

Post by **SATAN** » Sun Feb 10, 2008 8:43 am

Q451990 wrote:The typical method is to use a chain wrench wrapped around the pulley with some sort of protection (old belt) to keep from damaging the ribs - and brace it against something solid... like those crossmembers that run at a 45 degree angle. I certainly wouldn't use the parking pawl in the transmission to hold up to that kind of torque!

Heath

Doesn't matter, putting the car in park wont do **** for holding the engine still anyways LOL remember, you have a torque converter, not a clutch. This is why your engine will run while it is in park and in drive LOL

Post by **captainluigi** » Sun Feb 10, 2008 10:54 am

am wondering how many of us own or have access to a 9'' o.d. chain wrench. i bet someone has come up with an effective alternative. i will get a loaner 300'lb. snap-on torque wrench manana. who has gone the path of crank pulley replacement before? what did you use to hold crankshaft?

Post by **SATAN** » Sun Feb 10, 2008 2:31 pm

captainluigi wrote:am wondering how many of us own or have access to a 9'' o.d. chain wrench. i bet someone has come up with an effective alternative. i will get a loaner 300'lb. snap-on torque wrench manana. who has gone the path of crank pulley replacement before? what did you use to hold crankshaft?

Funny you ask that. Just this last Friday I had to take a length of about 3.5' of pipe, weld an 1/8" plate to the end of it, drill a 2" hole in the center of that plate to leave room to get a socket on the bolt. Drilled four more holes that line up with the holes that hold one of the extra pulleys, bolted it up, rested it on the ground and used a breaker bar to pop the bolt loose. BUT, this was on my Toyota 4runner. The Q45 only has the center bolt that hold the pulley on. No other bolts in the face of it.

Sorry guys.

Another thing you can do, but I will probably catch **** for this...

Put your big *** ratchet on the bolt, rest it on the ground making sure the socket is COMPLETELY on the bolt. Jump in the car, give the starter a little bump. The engine spins clockwise looking at it from the front so the bolt will stay in one spot while the engine rotates loosening the bolt. This still does not solve the problem of how you are supposed to torque it back up to 270 ft/lbs when you are finished though.

Dont be an idiot if you do this, give the starter little bumps, dont just hold it down. Also make sure the breaker bar is being pushed into the ground or into something that wont get damaged.

Post by **Drake57** » Sun Feb 10, 2008 4:15 pm

Surely you're not serious about bumping the starter. Sounds like a sure recipe for disaster.

Actually acheiving 270 ft-lbs is quite difficult for DIY mechanics. Are there any pneumatic driven impact wrenches capable of 270 ft lb with any way to be able to accurately reach that torque without over torque?

A few weeks ago I helped my son remove his crankshaft pulley from 1991 Q45 - I used one of the serpentine belts looped around the pulley, then put a lag bolt into a white pine 2x4 on edge to hold the other end of the loop - in effect a chain wrench. This served to remove the bolt no problem, although it likely was not torqued to factory spec, as this engine already had chain guide upgrade.

My question is: Is it safe to torque to spec using chain wrench or the like, expecting the pulley (that is attached to pulley hub with rubber) to be able to withstand that kind of torque?

The possible consequences of the bolt coming loose during operation are obviously many and severe. Was the mention of loss of oil pressure a generalization or is there a specific failure mode?

Thanks, Drake

Post by **SATAN** » Sun Feb 10, 2008 4:22 pm

Drake57 wrote:Surely you're not serious about bumping the starter. Sounds like a sure recipe for disaster.

Actually acheiving 270 ft-lbs is quite difficult for DIY mechanics. Are there any pneumatic driven impact wrenches capable of 270 ft lb with any way to be able to accurately reach that torque without over torque?

A few weeks ago I helped my son remove his crankshaft pulley from 1991 Q45 - I used one of the serpentine belts looped around the pulley, then put a lag bolt into a white pine 2x4 on edge to hold the other end of the loop - in effect a chain wrench. This served to remove the bolt no problem, although it likely was not torqued to factory spec, as this engine already had chain guide upgrade.

My question is: Is it safe to torque to spec using chain wrench or the like, expecting the pulley (that is attached to pulley hub with rubber) to be able to withstand that kind of torque?

The possible consequences of the bolt coming loose during operation are obviously many and severe. Was the mention of loss of oil pressure a generalization or is there a specific failure mode?

Thanks, Drake

Yes, I am serious. Like I said, I will probably catch **** for it, but it works. Have you ever bumped a starter before to turn an engine? If you just tap it, it doesn't spin but a couple degrees.

There is no impact wrench which can tell you what your torque is very accurately as far as I know.

The strap wrench has to work on the q45 harmonic balancer "with the rubber" because there is no other way to tighten it except for pulling the starter and wedging something in the drive plate.

Post by **Drake57** » Sun Feb 10, 2008 4:31 pm

I suppose there is no other way. I can't say for sure, but it is possible that the factory does have power impact drivers that are calibrated, which obviously does not help diy mechanics.

I'm sure I could fab a perfectly acceptable version of chain wrench in a couple of hours, but I'd just as soon buy one if they're not too dear.

Does anyone have a link to an acceptable chain wrench or tool supplier of such?

Thanks for the assistance.

Post by **AlabamaDan** » Sun Feb 10, 2008 6:08 pm

Wow. We just put it on as tight as we could get it and let it go on the last two QX4 we took the crank pully off with. I don't even know someone with a torque wrench that goes to 270fps. I haven't had any problems. Should I expect some soon?

Post by **SATAN** » Sun Feb 10, 2008 8:20 pm

Well... it is designed to be torqued that high so... who knows what you could see in the future.

Post by **marksport** » Sun Feb 10, 2008 10:41 pm

If you had the oil pan off, you could wedge something like a hard plastic rod or the handle of a hammer between the a rod and the block. This is from the '02 FSM on removing the pulley.

Mon Feb 11, 2008 6:56 am

GOOD IDEA BUT THAT..OOPS wont work on the Q45 if the motor is installed because you have to take down suspension crossmember just to get to the oil pan.Its a job!! not to mention taking off the pan after its just been siliconed.

Mon Feb 11, 2008 7:03 am

The reason there has to be so much torque is so the oil pump chain will turn. There is no keyway on the oil pump chain sprocket to make it turn, just to get it to slide on end of crankshaft,so yes the 270ft.lb. is critical because its like a fanblade turning when the fanclutch is going out, not constantly turning.

Mon Feb 11, 2008 9:16 am

how you doing dan! If i was you i wouldre-torque the crankshaft bolt so you dont take a chance of bearing failure in your engine!! If you dont have a torque wrench that goes to 270 just put a 3ft. pipe on a torque wrench set at 90ft.lb and that will give you the 270 you need.

Post by **captainluigi** » Mon Feb 11, 2008 10:28 am

still no resolution to the prob. of holding crankshaft in place while we torque.i have the 350'lb. wrench in possession, its in 3 pieces and stand 3'6''. i am removing the ''new'' crankpulley & checking the crank w/radial runout dial indicator. either i have a faulty ''new'' pulley or a bent crank or ?????? this DIYer sure has turned into a cluster fk. if crank is true i will be sending my original out for a rebuild. 1/2 the price & you get a guy with pride in his work doing one crankpulley at a time. except for the rubber curing stage that is.

subzero, perhaps you know some folks in the oil field biz. they may have just what you need. when i serviced the rigs in the gulf those guys had every tool known to man & a fab shop that rivaled a nascar team.

glk

Mon Feb 11, 2008 11:58 am

You are correct my friend!!(still doesnt solve our problem of how to hold pulley and keep it from turning) i actually have a 3/4 torque wrench that goes to 300ft.lb., that is not my problem.My problem is trying to figure out how to keep pulley from turning. anyone else have any light to shed on the subject??

Post by **AlabamaDan** » Mon Feb 11, 2008 1:01 pm

I read the FSM on my QX4, which is where I took the crank pully off. It reads 141-156fps. That makes me feel a little better. We probably got close to that with the big torque wrench and impact we used. But, I don't recall having to hold the pulley with anything. We put all the belts and everything back on first and tightened them. The engine held itself good and tight while we tightened the bolt. Perhaps that will work with the VH45?

Post by **Denver90Q** » Mon Feb 11, 2008 1:14 pm

2x4 wedged in between block and crank or a large chain wrench like they use on oil rigs. How did you keep it from turning when you took it off?

Post by **captainluigi** » Mon Feb 11, 2008 2:13 pm

DenverQ, i bumped the starter w/18'' brkr. bar & 30mm skt. attached. worked on my 454s, must remember strbrd. is counter rotating. my 502, & my 351s.& numerous trucks in popas fleet. would i encourage others to do this? no way! only for seasoned red necks.

AlabamaDan, not sure if the belts would hold against 275# but can see no clear reason not to over tighten for a trial & then being sure to adjust to proper tension afterwards.

Subzero, having never been to alaska i do not know whats around you. that being said you gotta have a deisel shop you could plead your case to. thats where i scored the chain wrench a few mins. ago. i work part time for a gov. agency. we have 4 helios, 2 planes & 6 flats boats & appx. 75 asst. trucks. not one chain wrench in the bunch. go figure.

Mon Feb 11, 2008 2:44 pm

When i took it off the engine was out of car with no tranny hooked to it, so i had access to flywheel!

Mon Feb 11, 2008 3:17 pm

captainluigi.........i never thought of trying to borrow a wrench from a local! WOW!! my cousin just brought me a chain wrench,he said its not a very long one,so.......we'll see!! I'll let everyone know how it TURRNNS OUT!LOL LOL Hopefully it doesnt.

Post by **Drake57** » Tue Feb 12, 2008 1:15 pm

I'd like to know if anyone actually has torqued to 270 ft-lb by holding crank pulley with chain wrench or the like - if the rubber where the pulley is bonded to the hub is at a radius of 3 inches, that puts a shear force of 1080 lbs at the joint - maybe no big deal, but it probably really puts it to the test.

I'm pretty sure I can fabricate a tool to hold the pulley at that torque, but I'd like to know that the pulley will actually take the strain - heaven knows what a replacement would cost.

Infinity is a number large beyond comprehension - sort of like Infiniti parts prices.

Post by **captainluigi** » Tue Feb 12, 2008 1:28 pm

sub, got some tropical satisfaction today. successfully reinstalled ''new'' crank pulley & torqued to 280 lbs. i did not have a acc. dr. belt i wanted to sacfrafice so i cut an app.size piece of 1/2 heater hose in half lengthwise. cut a slit in each end to wire tie it to pulley. removed obstructing idler pulley. kept it in place while i positioned chain wrench. applied initial tension w/brkr bar then put this monster 42'' 3 piece snap on to work. got another 1.5 turns on the bolt. click & done. new pulley wobbles but slightly less than old. have sent old of old to oregen for rebuild. meanwhile i am mobile again. dont forget the anti-sieze & locktite.

bueno suerte mi norte amigo

Post by **mxr662** » Sun Feb 17, 2008 1:28 pm

All this talk about crank bolt torque got me wondering. Originally used a heavy duty strap wrench which broke at around 230 foot pounds.

captainluigi wrote:am wondering how many of us own or have access to a 9'' o.d. chain wrench.

Bought mine today at Harbor Freight for $20. 24" aluminum handle which now has a very slight bend. Wrapped a leater belt around the pulley so it was double where the jaw of the chain wrench touched the pulley.

Q45tech wrote:Depending on arm strength [we have a complete gym at T3] you may have to adapt torque wrench with extension pipe.

Too little like 180-240 lb/ft can cause serious oil pressure problem!!!!!!!!!!!!

What about shoulder rehab. Mine is killing me.

Used my fine blackhawk torque wrench which goes to 250 foot pounds, and my right leg to go approx 1/4 turn past the 250 foot pound click. This will be revisited again with the proper torque wrench. I sure my blackhawk is inaccurate at any setting especially the max.

Post by **captainluigi** » Sun Feb 17, 2008 1:46 pm

Drake57, that is an interesting #. what is the math formula that got you to that answer. am trying to reverse it but not working. ciphering is not this keybillies longsuit. my only suit is a wet suit.

Post by **mxr662** » Sun Feb 17, 2008 2:26 pm

I think this is what Drake57 means:

My chain wrench is approximately the same length as my torque wrench. So if I pull with a force of 135 lbs in the correct direction on my two foot torque wrench it will require a force of 135 lbs in the opposite direction to hold the chain wrench and pulley still. This will torque the bolt to 270 ft/lbs. 135 lbs on a two foot wrench = 270 ft/lbs.

270 ft/lbs divided by 2 = 135 lbs needed to pull on my torque wrench270 ft/lbs divide by 4 = 67.5 pounds needed to pull on a 4 foot torque wrench.

Rubber in the pulley is what is holding all the torque. This is at a three inch radius or .25 feet so:

270 ft/lbs divided by .25 feet gives me 1080 lbs of force at the 3 inch point.

But I don't personally know how the pulley is constructed and many people on this thread suggest the chain wrench. In my younger days I remember pulling a 350 chevy harmonic balancer off with a 3 jaw puller and ending up with 2 pieces, one still attached to the engine.....

Andy

Post by **captainluigi** » Sun Feb 17, 2008 3:03 pm

ooooooook.

on the subject of the crank pulleys construction. i will have that info later in week. mine is @ dale mfg. dale disassembles then reassembles using the latest in elasomeric substance. god for continuous 400' F. very interesting guy.

Post by **sijoko** » Sun Feb 17, 2008 3:20 pm

I changed out the crankshaft pulley on my 95 Q. I removed it using an air impact gun and installed it the same way.

I put the selector switch to the 3rd position which is somewhere near 300 lbs-ft of torque according to my guesstimate. Seriously.....the main concern for me was making sure there was enough torque on the pulley so the oil pump would not slip.

I also used the red Loctite to keep things from coming loose. Hope this helps.

how do you tighten crank bolt to 270 ft. lb.??

how do you tighten crank bolt to 270 ft. lb.??

Re: how do you tighten crank bolt to 270 ft. lb.?? (SUB ZERO CAR FANATIC)

Re: how do you tighten crank bolt to 270 ft. lb.?? (SUB ZERO CAR FANATIC)

Re: how do you tighten crank bolt to 270 ft. lb.?? (Q45tech)

Re: how do you tighten crank bolt to 270 ft. lb.?? (Q451990)

Re: how do you tighten crank bolt to 270 ft. lb.?? (SUB ZERO CAR FANATIC)

Re: how do you tighten crank bolt to 270 ft. lb.?? (captainluigi)

Re: how do you tighten crank bolt to 270 ft. lb.?? (SATAN)

Re: how do you tighten crank bolt to 270 ft. lb.?? (Drake57)

Re: how do you tighten crank bolt to 270 ft. lb.?? (SATAN)

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Re: how do you tighten crank bolt to 270 ft. lb.?? (Drake57)

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