Need Strap or Chain Wrench

[mscher]

Ok engine pros,

I will neeed to hold the crankshaft pully (without it moving), on a V6 Nissan engine, in order tor remove the fastening nut.

The Haynes manual says to use a chain or strap wrench.

Will one like this work? If not, can you recommend a reasonable priced one that will?

http://www.craftsman.com/shc/s/p_10...me=General+Purpose+Tools&keyword=strap+wrench

 

[Knightgang]

Re: Need Strap or Chain Wrench

That might work, although it will be difficult...

Sounds like you might be trying to do a timing belt job...

One thing you might want to consider is to use an actelene torch or a propane torch with MAP gas to heat the nut and then hit it with a GOOD impact wrench to break it loose...

If there is a rubber bushing in the pulley, be careful not to get it to hot and damage it...

If this is the first time it has been off, then the thread lock that the factory used on it may be VERY difficult to break loose without the heat to soften it...

 

[Pascal]

Re: Need Strap or Chain Wrench

Remove the spark plug from the cylinder closest to that end of the crankshaft. bring the piston toward TDC and feed a sufficient length of clean rope into the cylinder to 'lock' the piston from moving past TDC while you loosen/tighten the pully nut/bolt. works best if you have piston on the compression/power stroke transition but intake/exhaust overlap shouldn't be a problem with having the valves open that little bit.

I use that method all the time to hold the crankshaft on small 2/4 stroke engines to remove the flywheels or drive sprockets on chainsaws.

 

[i386]

Re: Need Strap or Chain Wrench

I'm not an engine pro but...

That type of strap wrench won't grip quite as well as the skinny ones with a solid metal handle.

 

[walt-oxie1]

Re: Need Strap or Chain Wrench

First off, are you replacing the timing belt? Has the belt jumped or broken? If it has not broken here is a trick that will work. Place a socket and breaker bar on the crank nut, rest the breaker bar against the frame rail and bump the starter a few times real quick. It will loosen it. I have been using that method for 20 years and it hasn't failed me yet. I also used it not long ago on my folks V6 Frontier. Please do not try the rope trick mentioned above with any overhead valve engine. It does work great for some applications but can bend valves.

 

[pmat1]

Re: Need Strap or Chain Wrench

If its a manual transmission, just put it in gear and use the parking brake, but im sure you would have already tried that if it was manual.

 

[bruceb58]

Re: Need Strap or Chain Wrench

More than likely there is a tool you can buy that will do the job for you. I bought the tool for my Lexus GS300 when I replaced the timing belt. Yes, the tool ran me around $60 but it was the best money I spent on the job. Don't ruin your pulley...get the correct tool. Your pulley is going to run you more than the tool.

Don't do the bump the starter thing. If something slips off when you try that, you could be extremely sorry. Do the job right with the correct tool.

I hate Haynes manuals. I only use factory manuals when I work on anything.

While you are in there, replace your water pump, front oil crank seal, cam shaft seals and all tensioner pulleys.

 

[bruceb58]

Re: Need Strap or Chain Wrench

One thing you might want to consider is to use an actelene torch or a propane torch with MAP gas to heat the nut and then hit it with a GOOD impact wrench to break it loose...

First off, its not going to be a nut...it is going to be a bolt. And second, if its anything like my Lexus, it is torqued an with over 300 ft lbs. Yes, you heard me right 300! Heating will get you no place.

 

[j_martin]

Re: Need Strap or Chain Wrench

First off, its not going to be a nut...it is going to be a bolt. And second, if its anything like my Lexus, it is torqued an with over 300 ft lbs. Yes, you heard me right 300! Heating will get you no place.

Heating to around 300 degrees will make the loctite let go.

Vice grip makes a chain locking pliers that I use when I have to hold something round.

hope it helps
John

 

[Stachi]

Re: Need Strap or Chain Wrench

1/2 inch impact gun on the BOLT no heat , you don't want to change the hardness of the crankshaft or destroy the seal

 

[Knightgang]

Re: Need Strap or Chain Wrench

First off, its not going to be a nut...it is going to be a bolt. And second, if its anything like my Lexus, it is torqued an with over 300 ft lbs. Yes, you heard me right 300! Heating will get you no place.

Yes, it should be a bolt. However, i must disagree. I have watched a friend of mine do this many times at his shop. With the right heat, you can almost back out that bolt with a 3/8 ratchet and socket...

Heat metls the locktight, which is what you need, because the factory makes sure it will not come appart easily...

 

[mscher]

Re: Need Strap or Chain Wrench

This is a timing belt change, the 1st one. I have not started the job yet, just getting things together, to avoid surprises.

It is a manual transmission.

Following the steps in the repair manual, it stated that it was important that the pully did not turn, as the TDC is already set, from earlier steps.

 

[Bondo]

Re: Need Strap or Chain Wrench

Following the steps in the repair manual, it stated that it was important that the pully did not turn, as the TDC is already set, from earlier steps.

Ayuh,... Use the rope in the cylinder trick then...And put it in low gear...

 

[Pascal]

Re: Need Strap or Chain Wrench

Yup. .... Loosen the bolt then go through the steps to set TDC.

 

[puddle jumper]

Re: Need Strap or Chain Wrench

First off, are you replacing the timing belt? Has the belt jumped or broken? If it has not broken here is a trick that will work. Place a socket and breaker bar on the crank nut, rest the breaker bar against the frame rail and bump the starter a few times real quick. It will loosen it. I have been using that method for 20 years and it hasn't failed me yet. I also used it not long ago on my folks V6 Frontier. Please do not try the rope trick mentioned above with any overhead valve engine. It does work great for some applications but can bend valves.

I have also done this hundreds of times. Just remember to only bump the engine over. Make sure that you have the braking bar secure and resting/tied up against the frame in the right direction. For added protection slide a peace of plywood between your rad and the braking bar. Just in case it slips. UNDER NO CIRCUMSTANCES do not try to hold on to the bar and do this. If you can get an impact gun on the end of the bolt is the better way of doing it.

 

[Knightgang]

Re: Need Strap or Chain Wrench

You should not have to worry about setting TDC if you mark all of the gears and pullies during dissassembly before you take them off. If you are diligent is reference marks, then it will all go back together just as it was...

 

[j_martin]

Re: Need Strap or Chain Wrench

Them that can, do. Them that can't, teach..... or write manuals.

A little common sense goes a long way. Loosen the bolt and then do the timing lineup makes sense.

hope it helps
john

 

[bruceb58]

Re: Need Strap or Chain Wrench

I have also done this hundreds of times. Just remember to only bump the engine over.

And how would you suggest tightening it?

 

[puddle jumper]

Re: Need Strap or Chain Wrench

And how would you suggest tightening it?

Your right tightening is a different story. If you take off the pulleys off the harmonic balancer and bolt a long plate to it and rest it against the frame you then can then torque it down. A manual will show you what it looks like.

The best way to get it off and on is with a impact wrench. Even if you have to take the rad out.

 

[bruceb58]

Re: Need Strap or Chain Wrench

The best way to get it off and on is with a impact wrench.

Uh...no. You never use an impact wrench to tighten anything. Always use a torque wrench.

I see on your profile you are an auto mechanic(you spelled mechanic wrong so maybe not) You really use am impact gun on engine crankshaft bolts?