Cam Tower Bolt Torque

[DOOM]

I was torquing down my camshaft bearing tower bolts, with torque settings according to 'How to Rebuild your L series' and cleanly stripped the threads out in the cylinder head. So I am guessing that the book is incorrect or I'm blind.

 

So anyway what is the correct torque settings the cam tower bolts?

[dat2kman]

What does the book say?

Post a pic/scan f the paragraph in question.

 

Kinda hoping you didnt read head bolt torque, as one side of towers are right through to blck,,,,

[oldmates260z]

Here's one link

 

http://www.biopatent.com/engine.html

 

"The cam gear should now fit snugly at the end of the cam shaft with the cam peg fitting into the number 1 hole of the cam gear.  Torque the camshaft gear bolt to 43 ft-lb."

 

"Finger tighten, then torque all the bolts (starting again from the center) to about 35 ft-lb and finally torque all the head bolts to 54 ft-lb."

 

[Riceburner]

I read it as being the cam tower bolts, IIRC the setting is somewhere around the 10-12ft-lb.

 

Also the correct setting for the cam sprocket bolt is 87-116ft-lb.

[DOOM]

This is not realted to headbolts at all, this is the camshaft tower bolts that hold the camshaft towers in place.

These ones:

 

Here is what the text says from 'How to Rebuild Your Nissan & Datsun OHC Engine'.

 

And again here on the next page

 

I first cleaned up the bolt thread with a wire wheel. Then oiled bolt threads and underneath the head of the bolt. I had the camshaft in place whilst torquing. I used a 40 Nm to 200 Nm Teng torque wrench (prehaps too big?) Also noticed that the smaller bolt (one that stripped) was missing a dowel for the camshaft tower (maybe another reason why thread stripped). Mind you the threads that stripped was female aluminium inside the head. Also the longer camshaft tower bolt kept spinning like it had stripped a thread but when inspected threads inside the head appeared fine. The above was attempted only once on the first camshaft tower.

 

I'll obviously need a helicoil to fix this but I'd like to know if I was using the wrong torque amount.

 

 

[DOOM]

I read it as being the cam tower bolts, IIRC the setting is somewhere around the 10-12ft-lb.

 

Also the correct setting for the cam sprocket bolt is 87-116ft-lb.

 

Thats what I was after, thanks Gareth. Where abouts did you find this information? Its in none of the manuals I have.

 

Also thanks dat2kman and oldmates for input.

[peter t]

Go to page 158 of your How to Rebuild book and all the correct settings are there.

[luvemfast]

Love how they give 3 different types of torque figures......

Nm, ft-lb and kg-m

Seriously messed up!

[DOOM]

Love how they give 3 different types of torque figures......

Nm, ft-lb and kg-m

Seriously messed up!

 

And its about double the torque of what the 'How to Modify' book claims.

[dat2kman]

Love how they give 3 different types of torque figures......

Nm, ft-lb and kg-m

Seriously messed up!

Why they do, is due to different countries using different technical Unit formats.

The broadest unit is the Foot-Pound.

Eg, it is easier to comprehend a 250 pound spring, and a 300 pound spring, compared to a 7kilogram spring and an 8 kilogram spring ( suspension)

By using the broadest scale of Unit, your end result s more accurate.

It does not help when your Torque wrench has all three Unit scales on it!

 

Yes it is easy to mck it up. Always use the phrase " Measure twice, cut once."

[luvemfast]

I always convert to Nm, as its easier to understand.

Kg-m is close to 10%, given that 1kg is approx 9.81N.

Ft-lb is purely for the crazy Murican's still using fractions!

[peter t]

I am from the old school and always use ft-lb and haven't stripped a thread in 45 years using this measurement. Its just a case of choosing one type of measurement scale and sticking to it then as the years float by you never encounter problems.

[peter t]

This is not realted to headbolts at all, this is the camshaft tower bolts that hold the camshaft towers in place.

These ones:

 

Here is what the text says from 'How to Rebuild Your Nissan & Datsun OHC Engine'.

 

And again here on the next page

I cant find that page in my book. Do you have a page number?

 

I first cleaned up the bolt thread with a wire wheel. Then oiled bolt threads and underneath the head of the bolt. I had the camshaft in place whilst torquing. I used a 40 Nm to 200 Nm Teng torque wrench (prehaps too big?) Also noticed that the smaller bolt (one that stripped) was missing a dowel for the camshaft tower (maybe another reason why thread stripped). Mind you the threads that stripped was female aluminium inside the head. Also the longer camshaft tower bolt kept spinning like it had stripped a thread but when inspected threads inside the head appeared fine. The above was attempted only once on the first camshaft tower.

 

I'll obviously need a helicoil to fix this but I'd like to know if I was using the wrong torque amount.

[peter t]

Yep found the page that it is on. Must be a typo. Thank goodness I didn't see that when I put mine back together.

[pauly_adams]

do yourself a favoure and use a time sert instead of a helicoil

 

http://www.timesert.com/

[luvemfast]

do yourself a favoure and use a time sert instead of a helicoil

 

http://www.timesert.com/

I've not used those before.

Why do you think they're better than Helicoils?

[pauly_adams]

there a threaded bush, helicoil can come out where as timesert stays locked into the position, you can do up and undo as many times as you want with out worrying about pulling out the coil

[PB260Z]

do yourself a favoure and use a time sert instead of a helicoil

 

http://www.timesert.com/

 

When I needed a thread repair on the old XY 4X4 this is exactly what was used. Very happy with the results.

 

I have the number of a mobile guy in Sydney's north who uses them if anyone needs it.

 

Cheers

 

PB