Bad Head Torquing?

hey guys, late to this thread, but I have a question for y'all- I'm going to re-torque my head per the instructions here as Im weeping oil on the left side. However, the acorn nuts are STUCK pretty good. I pulled out my torque wrench and tried to loosen them, and it feels as if the studs want to move before the nuts budge. Any advice for loosening them? I don't want to snap a stud... I've tried doing it with the motor nice and hot, and nothing... I'm not pushing too hard tho... should I really lay into the nuts? How much 'persuasion' is too much? Any advice is very appreciated!
 
Do all this on cold engine. Try tapping on top of acorn nut with small hammer while trying to loosen. If no-go, continue tapping while trying to tighten, then loosen, going back-and-forth. If still no-go, heat acorn nut only, quickly, with propane torch, and retry the above, quickly...
 
Hi guys
I bought an xs from a guy about 6 years ago, and hardly touched it.
I had 6or 7 two strokes that I fiddled with and raced.
Eventually had to sell everything :-(

Went back to the guy I sold the xs to, and he sold it back about 6 months ago.

Had always been difficult to start, and the starting rollers at the track days was the only real chance.

Always knew it was something special with the halco tuning badge.

Decided to build a cafe racer, so for the first time ( in my hands ) the motor came out.

Careful measurements tell us 95mm stroke and 87.5 pistons.

The motor was done in Johannesburg by a guy who would fly to halco in the uk with cranks in his hand luggage!!

I'm now going to try post pics..
 
This is worth looking at, on the subject of torque wrenches. Keep a close eye on your reading and if the nut is turning but the torque isn't increasing you're starting to strip or stretch. If you don't stop you'll be sorry... Even if you're reading way under the target torque.

http://home.jtan.com/~joe/KIAT/kiat_3.htm

WMX,
depending age use and being reset to 0 all torque wrenches should be calibrated via a tool shop.

leslie
 
^Sure, but how practical is that. There's a big problem which is the bolt could be in the middle of tearing, or you might just be squishing down a gasket or bushing, Hard to say. Worth mulling over. BTW, I have a beam wrench which is easy to calibrate - just bend the pointer :) But it's an SK made in USA bought new around 1984, so who knows. Would be fun to test it against some known good recently calibrated high quality clicker wrench.

A sort of a secondary problem is you don't necessarily know what's happened to the bolt before. It might have been on the threshold of having its threads torn off some time in the past, and weak. So feel is something to consider.
 
jonny reb, never use a torque wrench to loosen things it throws the calibration off. Use a breaker bar if your rachet isn't enough. They nuts and bolts to tend to seize up a bit and can take a bit of grunt to loosen.
A hand impact wrench helps, not an air or electric, the kind you whack with a hammer. It's a good investment, it comes in very handy to get screw loose with out stripping the heads.
Leo
 
Oh, and one more thing - i know the main bolts are 37lbs, the rear is 7, and the rest are 11, and i have the pattern.

I'm thinking of torquing in stages
1 - the mains at 10
2 - the mains at 20
3 - torque to spec the 7 and 11's
4 - the mains at 30
5 - the mains at 37

Doing this *should* eliminate squish-out of the gasket.

Does anyone have an issue with this, or any other suggestions?

I've been riding a '77 XS650D since I bought it new. My opinion of the best method to torque the head is to torque all bolts in 3 stages using the sequence shown in the manual. Use 1/3 of the required foot pounds each time. I've been doing it that way for
37 years with great success. (Oil all threads first with motor oil)
 
Oh, and one more thing - i know the main bolts are 37lbs, the rear is 7, and the rest are 11, and i have the pattern.

I'm thinking of torquing in stages
1 - the mains at 10
2 - the mains at 20
3 - torque to spec the 7 and 11's
4 - the mains at 30
5 - the mains at 37

Doing this *should* eliminate squish-out of the gasket.

Does anyone have an issue with this, or any other suggestions?

I've been riding a '77 XS650D since I bought it new. My opinion of the best method to torque the head is to torque all bolts in 3 stages using the sequence shown in the manual. Use 1/3 of the required foot pounds each time. I've been doing it that way for
37 years with great success. Oil all threads with motor oil first.
 
Hi
I'm new to this forum and have read this thread with great interest. I've got a tx650 in good health now but have been chasing an oil leak. Added copper washers to the head studs but when i removed each acorn nut i found a slight looseness or wobble in each stud. I could not tighten them either. Is this normal or do i have something sinister going on? all nuts torque up nicely to spec and motor is dry so far.

Thanks for any advice.

Kon
 
XS Leo- I meant socket wrench! Torque wrench must have been on my brain back then... Anyway, thx for the advice. Ended up tearing down the top end over Xmas. Runs great now, no leaks. Also, Kon, do you mean the studs wobble in the passages with the nuts removed? That's normal for such long skinny studs.
 
Hi Jonny
Yes after removing the acorn nuts, the studs just seem to have a little bit of back and forth play. From your post that is normal right?

Kon
 
Hi Jonny
Yes after removing the acorn nuts, the studs just seem to have a little bit of back and forth play. From your post that is normal right?

Kon

Jonny is right. The studs are very long and will flex when the nuts are off.
 
Kon- yes, a little back and forth is fine. As long as the stud is screwed all the way into the case, there's no problem. They are also oil passageways, so there has to be a bit of room around them- make sure nothing falls in there when you're wiggling them around!
 
Thanks guys

I'm planning a ride to work tomorrow so my head tightening success will be indicated by the hopeful lack of oil stains on my trousers

Kon
 
Looks like the head studs are now oil tight. I'll now have to check for solutions to leaks from the oil breather box and the advance mechanism, as there appear to be some minor leaks from there.
 
On the torque specs stock the 8 big nuts get 27 ft/lbs. Often this spec gets upped to 30-32 ft/lbs. Not 37. That will be too much.
Doing the torque in stages of around 1 third is a good idea. This help prevent warpage.
Leo
 
Hi Guys,

So I started to tackle this today and I have a few questions I was hoping I could get help with:

- I bought a decent torque wrench that is rated up to 220 pounds. I set it up for 30 lbs for bolts 1-8 and it seemed like it wasn't very tight. It wasn't much more than hand tight before it clicked. Is that normal? It is way less tight then it was before but maybe that was what was causing the leak.

- I am using the manual for the torquing pattern, and I'm assuming bolts 13 and 14 are the ones under the spark plugs, but I can't find #15 in the front of the engine. In the diagram it looks like it is where the oil tube is but that doesn't seem right.

- I bought the copper washer kit from Mike's and it comes with 9 washers. I think I only need to use the 4 on the outside bolts (5-8). Is that correct?

Thanks!!
 
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