replacing cylinder head studs?

[monster_energy06]

for a while ive been thinking of replacing my cylinder head studs with bolts instaid. i have a bunch of cylinder head bolts off my parted out sled engines that would work perfect.. has this been done befor?? would it cause any problems. reason im askin is beauce, im instaling my cool head soon, and would like to do this while im there if its posible. tx

[okbeast]

I asked this awhile back and got a 'no'. I don't remember why though, someone else will chime in i'm sure.

[Bansh-eman]

i dont see why it wouldnt work, most other motor iv ever worked on beside quads and dirt bikes use bolts instead of studs.

[No Limit Powersports]

It would probably work fine but studs are always better. You get more thread in the motor before tq so you have less of a chance of pulling the threads on the cylinder. Plus you will get a more acurate tq reading from a nut rather than a bolt. So to answer your question will it work yes but my question is why studs are not that expensive especially if you pull a thread and have to heli coil or time cert.

[gregrob]

I don't think it's a good idea because everyt ime youremove and replace your head you will be threading the bolt into an alumium cylinder...

 

The studs are steel and are designed to withstand the fatige that the engine puts on them as well as being used multiple times.

 

A normal bolt / threaded hole configuration doesn't stand up to the kind of abuses put on them by cylinder heads too well. Every time the engine fires it stretches the bolt, and it has to be the proper tensile strength and composition to return to its original state without cracking or breaking due to the fatigue.

 

 

The bolts you have for the snowmobile head may work fine but I would definitely recommend against using a common fastener for this task, and I still don't think you would get by very long without stripping the threads in the cylinder.

 

 

I do fasteners for a living so just letting you know what I've learned.

[monster_energy06]

It would probably work fine but studs are always better. You get more thread in the motor before tq so you have less of a chance of pulling the threads on the cylinder. Plus you will get a more acurate tq reading from a nut rather than a bolt. So to answer your question will it work yes but my question is why studs are not that expensive especially if you pull a thread and have to heli coil or time cert.

its not a mather buying new studs. the ones i have are fine. i alway found it easier not having studs in the way, while installing a head, or in my case making sure my o-rings will seat propurly on my cool haed

 

I don't think it's a good idea because everyt ime youremove and replace your head you will be threading the bolt into an alumium cylinder...

 

The studs are steel and are designed to withstand the fatige that the engine puts on them as well as being used multiple times.

 

A normal bolt / threaded hole configuration doesn't stand up to the kind of abuses put on them by cylinder heads too well. Every time the engine fires it stretches the bolt, and it has to be the proper tensile strength and composition to return to its original state without cracking or breaking due to the fatigue.

 

 

The bolts you have for the snowmobile head may work fine but I would definitely recommend against using a common fastener for this task, and I still don't think you would get by very long without stripping the threads in the cylinder.

 

 

I do fasteners for a living so just letting you know what I've learned.

tx for yur input ,its well noted, i have never striped a head bolt in any of my cylinder ever.... it shouldnt either. at only around 20flb of tork imo . yes the bolts i have, are for engine purpose there around 3-4$ a bolt.. like i said above i find the stud to be in the way

tx for all the help

[gregrob]

It's not the amount of torque, which I agree isn't all that much, it's the constant use / reuse of threading it into the aluminum cylinder.

 

 

If the cylinder was designed for that repeated use it would be fine, but a banshee cylinder is not.

 

I'd say it would work for a while, I'd just keep some heli coils handy in the toolbox if you go that way.

[Animalman294]

My vote is to use the studs and leave the bolts out.........................

[Wildcardracing]

Something not mentioned yet is that a lot of the cool heads need studs because they have o-rings that seal on the non-threaded portion. If it is a one piece head with copper washers then the bolts would work, but I too recommend studs. Why do you think that in so many performance applications bolts are replaced with studs??? Just something to think about.

[monster_energy06]

It's not the amount of torque, which I agree isn't all that much, it's the constant use / reuse of threading it into the aluminum cylinder.

 

 

If the cylinder was designed for that repeated use it would be fine, but a banshee cylinder is not.

 

I'd say it would work for a while, I'd just keep some heli coils handy in the toolbox if you go that way.

thats exacly what i wanted to know, if the cylinder were designed for studs only .. i might try it tho. all my sled jugs are aluminium and i take the head off alot

Something not mentioned yet is that a lot of the cool heads need studs because they have o-rings that seal on the non-threaded portion. If it is a one piece head with copper washers then the bolts would work, but I too recommend studs. Why do you think that in so many performance applications bolts are replaced with studs??? Just something to think about.

ya i though about that alot. witch is why i wanted bolts to seal the top also have stat-o seal washers to put on witch will seal it even better

 

will see what happens, and i might try it

Edited May 23, 2008 by monster_energy06