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Heads and Cylinders All about your porting, compression, rings, cylinder and piston modifications to your bicycles engine

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  #1  
Old 12-29-2015, 08:48 AM
Flathead Flathead is offline
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Default Headbolts

If I have no tools with gauges is oversnugg OK for head bolts?
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Old 12-29-2015, 10:31 AM
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2door 2door is offline
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Default Re: Headbolts

That all depends on your experience with fasteners. "Snug" to you might mean one thing and something different to someone else. As I've said here many times, over tightening fasteners has caused more problems than any other one thing with these kits. In the case of the cylinder head too loose or too tight can cause you further problems.

Trying to 'guess' about proper torque is not a good idea. I'd check around and try to find someone who will either loan you a torque wrench or tighten the fasteners for you. The problem with having someone do it for you is you'll need to go back to them after a few heat/cool cycles and have the torque 'checked' a couple of times after the initial tightening.

Save a few bucks and buy a torque wrench. It'll be cheaper than the repairs you might have to make by not using one.

Tom
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Old 01-08-2016, 02:02 AM
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ZipTie ZipTie is offline
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Default Re: Headbolts

I'm a newbie to these engine kits also, but common sense says...Better to be bit too loose than too tight. If you don't get the torque wrench then air on safety and hold the wrench near the bolt so you have less leverage and snug them up that way.
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Old 01-08-2016, 07:22 PM
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sbest sbest is offline
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Default Re: Headbolts

Too loose ends up like this:

Blown head gasket.

Too tight means head studs stripped out of the case. ARGH!

A torque wrench is a great investment, much cheaper than broken stuff.

Steve
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Old 01-08-2016, 07:37 PM
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allen standley allen standley is offline
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Default Re: Headbolts

I concur. Harbor Freight 10 bucks.
http://www.harborfreight.com/catalog...tourque+wrench
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Old 01-10-2016, 11:13 AM
crassius crassius is offline
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Default Re: Headbolts

failure in the head studs most often is caused by the acorn nut binding on the threads - if you are using open nuts, then you will be a bit safer if you can't get a torque wrench to do it right

less common, is the threads of the stud pulling out of the cylinder, I always loosen the studs a bit & reseat them to be sure the threads seem to be performing correctly and weren't left loose or cross threaded at the factory
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Old 01-12-2016, 07:31 PM
buba buba is offline
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Default Re: Headbolts

Cylinder stud -case metal sucks what is a non helicoil fix when a head gets lose and compression firing causes a stud to strip in case???--Anyone??? success stories???
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Old 01-12-2016, 07:47 PM
crassius crassius is offline
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Default Re: Headbolts

haven't done it on HTs, but always used to drill large to put in brass bolt - cut it flat to the surface & file area smooth - drill it to take proper size threads

was successful on motorcycle cases, heads, & cylinders all thru the 50s & 60s, as brass has very similar expansion to aluminum

amount of hand work makes replacement cheaper tho if you're paying for that labor
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Old 09-11-2016, 08:09 AM
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Default Re: Headbolts



What kind of specific socket size....and length does one use to get at these piston head bolt caps ??


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  #10  
Old 09-11-2016, 09:42 AM
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mogollonmonster mogollonmonster is offline
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Default Re: Headbolts

Either 12-14mm, I believe the Dax motor I'm running is 14mm. Standard sockets are deep enough, although an extension might be necessary to clear the cooling fins. I always use 1/4 inch drive, to keep me from being over zealous. I don't own a torque wrench, but I'm one of them who can "feel" torque, I've been turning wrenches a long time, and I'm familiar with the sensations of steel preparing to give. There is no fastener on these engines that needs to be that tight. I do not always torque wrench, but when I do, I use the needle type.

Buy one, it'll save your bacon. Most of my repairs are done on the roadside, well away from anyone and anything, crosslegged on the shoulder of some lonely highway. Those situations are rarely conducive to proper equipment usage. After making a head gasket out of a bud lite can with a razor knife, just get the thing tight and get it home. That is not the proper way of things, buy a torque wrench.
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