Topic: Double nut technique for studs?

[cakey]

Sounds like a stupid question but I am putting my new head back together on my CB750 K1 and just having problems torquing up the 4 studs to 90 inch pound. I go 40, then 70 and when I go for 90 both nuts start winding down the thread. I gorilla tighten them together and it still happens.

Does anyone know a trick to this or another way? I didn't have a problem when I was doing the cylinder studs with the 8mm thread but this 6mm isn't doing it for me.

Thanks

[jpfrk2001]

Did you try tightening down the outer nut to the inner nut with two actual wrenches? Then when you torque with the TQ Wrench, make sure the socket is only on the outside nut. Not both. I've done this technique my self. And Im applying up to 60 FT/LBS on some of the studs Im installing in said part.

[cakey]

Did you try tightening down the outer nut to the inner nut with two actual wrenches? Then when you torque with the TQ Wrench, make sure the socket is only on the outside nut. Not both. I've done this technique my self. And Im applying up to 60 FT/LBS on some of the studs Im installing in said part.

Sorry mate when you say 'wrenches' do you mean 'ring spanners'? If so then no I used open ended spanners.

You might be right about letting the socket go over both nuts because I was looking down on them and not side on, so will double check that as we'll.

Thanks for the advice.

[jpfrk2001]

Did you try tightening down the outer nut to the inner nut with two actual wrenches? Then when you torque with the TQ Wrench, make sure the socket is only on the outside nut. Not both. I've done this technique my self. And Im applying up to 60 FT/LBS on some of the studs Im installing in said part.

Sorry mate when you say 'wrenches' do you mean 'ring spanners'? If so then no I used open ended spanners.

You might be right about letting the socket go over both nuts because I was looking down on them and not side on, so will double check that as we'll.

Thanks for the advice.

Ahhh. I see your down in AU. So yea, two ring spanners than. Use two ring spanners on the nuts first to tighten against each other first. Then come back with the TQ wrench and make sure you are applying TQ only on the outer nut. Not both.

No problem for the advice. Report back if it that works.

[70CB750]

Also it pays to use high grade nuts, like 8 or so.  If you go with regular box store grade, you know, the shiny, cheap stuff, the nuts will deform under pressure.

[crazypj]

The only thing I've found that works without causing any distortion or damage to threads is a Snap-On CG500 stud tool.
It uses tapered collets similar to R8 milling holders. but, threaded for whatever studs your using. (yes, you need different collets for each thread)
The only 'problem' with it is the price, particularly if your only going to use it once ($108 when I bought mine several years ago)

[markb]

Here's a tool I use for intalling studs.  I have one for the cylinder studs and a smaller one for the studs on the head.  You can buy them but I made these.  The hex is tapped through.  You spin it on the stud and bottom the screw on the end of the stud and no slipping. 

[flybox1]

@ markb - nice work. simple and effective!
what would those hex sections be called?

[70CB750]

@ markb - nice work. simple and effective!
what would those hex sections be called?

Coupling nuts:

http://www.homedepot.com/p/Unbranded-1-2-in-13-x-1-3-4-in-Zinc-Plated-Rod-Coupling-Nut-25-Pieces-19157/100337862#.UmU1TRASTP8

[markb]

Coupling nuts:

http://www.homedepot.com/p/Unbranded-1-2-in-13-x-1-3-4-in-Zinc-Plated-Rod-Coupling-Nut-25-Pieces-19157/100337862#.UmU1TRASTP8

I just cut off a piece of hex stock and tapped a hole through it but that is a cheap, easy way to do it. 

[Don R]

I can't get used to torquing studs into a hole. On my big engines we just go finger tight with some locktite. Is 90" lbs really the correct torque for inserting the stud? Just asking.
 When I remove studs, I use two spanners on the nuts and turn them together while holding tension on the spanners. Sometimes I use a washer between the nuts just to seperate the wrenches. (Spanners)

[markb]

Is 90" lbs really the correct torque for inserting the stud?

That's the torque I've used for APE studs, actually 96 in-lbs max is their spec.  I don't think I've ever seen a Honda spec for stock studs.

[iron_worker]

I think 90in*lb for bottoming out a 6mm stud is too much. I used 8ft*lb or 96in*lb on the main cylinder head studs.

If I were you I would just snug them into the hole and make sure you get the proper torque on the nut when you're installing the cam bearing caps. If the torque is correct on the top nut then there will be tension on the thread in the head as well as in the thread on the nut end. It should not back out if it's torqued correctly. A little blue loctite if you're really nervous about it could help.

IW

[MCRider]

They don't require that much torque, you can get by with 60in lbs. I think you've got good answers, so I bring up something else.

If you've had those studs out, have you put a sealer on them upon reinstalling? I used a Teflon thread sealer per MRieck.

Once you've broken the original factory seal, if you don't seal them back again they will wick oil down their holes which are open to the atmosphere in each of the spark plug areas. God awful mess.

First hand experience, plus Ken at Cycle X warns about this.

[Don R]

Sounds like you have good info. I'd proceed accordingly.

[markb]

I think 90in*lb for bottoming out a 6mm stud is too much. I used 8ft*lb or 96in*lb on the main cylinder head studs.

I could be wrong but I thought the original post was about the 8mm cylinder studs.

Once you've broken the original factory seal, if you don't seal them back again they will wick oil down their holes which are open to the atmosphere in each of the spark plug areas. God awful mess.

Referring to the 6mm studs on the head, you are correct.  I even had one that wicked oil and had never been removed.  So I always make sure they're sealed.

[MCRider]

I think 90in*lb for bottoming out a 6mm stud is too much. I used 8ft*lb or 96in*lb on the main cylinder head studs.

I could be wrong but I thought the original post was about the 8mm cylinder studs.

Once you've broken the original factory seal, if you don't seal them back again they will wick oil down their holes which are open to the atmosphere in each of the spark plug areas. God awful mess.

Referring to the 6mm studs on the head, you are correct.  I even had one that wicked oil and had never been removed.  So I always make sure they're sealed.

The OP was about the 4 - 6mm studs.

re: sealing. Never heard of one leaking that had never been disturbed. But I'm sure it can happen.

[lucky]

@ markb - nice work. simple and effective!
what would those hex sections be called?

Many hardware stores call them "stand offs"
Getting them in metric size could be difficult.

[markb]

I could be wrong but I thought the original post was about the 8mm cylinder studs.

Ooops, I have to pay attention better.

[cakey]

Well it's bloody lucky that I posted the question. There are some great answers but the most concerning is sealing the studs. If I use a high temp loctite will that be ok? I haven't heard of the thread sealer but I will ask at the seal and bearing place.

It makes sense what you are all saying about too much torque. They are a smaller thread size than the cylinder studs so you would imagine the thread could be less.

Thanks

[markb]

I checked my notes and I've torqued the 6mm studs to 40 in-lbs and never had a problem.  I used a Loctite product for the threads.  Not sure if it was specifically called a thread sealer.

[NobleHops]

Here's a tool I use for intalling studs.  I have one for the cylinder studs and a smaller one for the studs on the head.  You can buy them but I made these.  The hex is tapped through.  You spin it on the stud and bottom the screw on the end of the stud and no slipping. 

That is slicker than a smelt.

[cakey]

I checked my notes and I've torqued the 6mm studs to 40 in-lbs and never had a problem.  I used a Loctite product for the threads.  Not sure if it was specifically called a thread sealer.

Really appreciate the advice. They are coming out. Thread sealer on and back down to 40 in-lbs.

[MCRider]

Here's the Loctite brand thread sealer:
http://www.iboats.com/Loctite-Thread-Sealant-Teflon-Permatex/dm/view_id.70006?cm_mmc=Google_Main-_-Mall+Product+Listings%3AGoogle-_-+%3AMall+Product+Listings%3AGoogle-_-Permatex&kw={keyword}&gclid=CN_Bm_GRqboCFdJj7Aod00EAHQ

Oops this is Mislabeled Loctite and is Permatex.

I used a different brand name but it had the Teflon in it, per recommendation from MRieck.  Might have been this: http://texas-speed.com/p-166-arp-teflon-thread-sealer.aspx

Shop's locked up and I'm going to sleep.

Loctite brand thread lock probably works to seal it also. But I think the thing is you're not looking to lock these studs in as much as you are looking to seal them from oil leaks. May be a small difference, but what the?
http://www.loctiteproducts.com/p/t_lkr_blue/overview/loctite-threadlocker-blue-242.htm

[cakey]

I rang my local bearing and seal place here in Darwin and they recomended this thread sealant below. he said that it has teflon in it and would be more than suitable. Loctite 567

Loctite ® 567™ PST ® Thread Sealant
Loctite® 567™ PST® Thread Sealant is a general purpose instant sealer for tapered and straight/tapered fittings. With excellent solvent resistance, it can prevent galling and withstand temperatures up to 400° F (204°C). Excellent for high pressure applications: locks and seals tapered metal, pipe threads and fittings. It is ideal for stainless steel, aluminum, galvanized metal and other inert metals. Disassembles with hand tools.


Loctite Thread Sealants
Thread sealants prevent leakage of gases and liquids from pipe joints. All such joints are considered to be dynamic due to vibration, changing pressures or changing temperatures. Loctite anaerobic sealants cure to insoluble tough plastic thread fillers which prevent leakage regardless of the torque applied.

[cakey]

 Just wanted to thank everyone for advice and assistance on this. It's all done and finished and having another look at the position of those studs I can see why you would get the oil leak into the spark plug area. I think you guys saved me a lot of heartache down the track letting me know about the sealant.

Very much appreciated.

[MCRider]

When it happened to me it was a real eye-opener. I couldn't figure for the life of me where the oil was coming from. It would emerge on about the 3rd fin halfway between the rocker box gasket and the head gasket. So it couldn't be either one of those. I thought it was the pucks and since I had the APE frame rail kit I replaced those, to no avail.

I finally on a whim looked in between the fins with a flashlight while it was running and could actually see oil drops forming and dripping off the botttom of the the stud holes. So that answered the question. But I had lots of other issues too, and shortly after that it got parked, so I never fixed it.

However, my current project is nearing completion and I know more now.

[City Boy]

Hi gang.Would it be safe to assume that the tower cap bolts opposite the studs would be subject to the same issue and should have sealer applied also?         Rock On

[MCRider]

Hi gang.Would it be safe to assume that the tower cap bolts opposite the studs would be subject to the same issue and should have sealer applied also?         Rock On

No. The 4 bolts on the intake side thread into blind holes, no way for them to leak.