Author Topic: Cylinder stud too short!!  (Read 1730 times)

Offline Nurse Julie

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Re: Cylinder stud too short!!
« Reply #15 on: February 19, 2018, 03:56:11 PM »
Definitely a copper washer under that one then. Looking at your photo, you can really see the difference in lengths.
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Offline Fogdevil

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Re: Cylinder stud too short!!
« Reply #16 on: February 19, 2018, 04:00:38 PM »
Just noticed Orcadian's measurement parameters.I can relax-my studs haven't stretched by 22mm!!

Nurse Julie-what's this technique with double-nutting?Sounds very useful.Especially the part about saving me having to take the barrel off.

Offline Nurse Julie

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Re: Cylinder stud too short!!
« Reply #17 on: February 19, 2018, 04:01:04 PM »
Another little observation, the dowel on the 2nd stud in on the left at the back, it seems to be sitting very much to the left hand side of the stud where the one on the other side is central.
« Last Edit: February 19, 2018, 04:22:07 PM by Nurse Julie »
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Offline Nurse Julie

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Re: Cylinder stud too short!!
« Reply #18 on: February 19, 2018, 04:04:09 PM »
Just noticed Orcadian's measurement parameters.I can relax-my studs haven't stretched by 22mm!!

Nurse Julie-what's this technique with double-nutting?Sounds very useful.Especially the part about saving me having to take the barrel off.
Put two nuts of the correct size on the top of the stud, wind them down a little and then wind the bottom one up, the bottom one will lock against the underside of the top one and the stud should turn.
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Offline Orcade-Ian

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Re: Cylinder stud too short!!
« Reply #19 on: February 19, 2018, 04:06:31 PM »
yes, parts list indicates 122mm but that is the overall length, not the distance above the case when fitted.  Not sure if you can wind them out with the barrels on but worth a careful try.  Your studs are already the right way up so initial length must be suspect.

If you back it out a few threads don’t tell Trig.  I would investigate further before bodging is even contemplated.


Just a thought - there isn’t another thick washer stuck to the head is there?

If I get the chance later I’ll drop my barrels on the case and measure the distance above the deck for that stud - the only difference would be the base gasket thickness.

Offline Nurse Julie

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Re: Cylinder stud too short!!
« Reply #20 on: February 19, 2018, 04:11:20 PM »
yes, parts list indicates 122mm but that is the overall length, not the distance above the case when fitted.  Not sure if you can wind them out with the barrels on but worth a careful try.  Your studs are already the right way up so initial length must be suspect.

If you back it out a few threads don’t tell Trig.  I would investigate further before bodging is even contemplated.


Just a thought - there isn’t another thick washer stuck to the head is there?

If the studs have only recently been inserted, they shouldn't be corroded in, which is a good start.
I had a copper covered steel washer stuck when I took mine apart, It took me no end of picking to get the blighter out, it was well stuck in there.
Yes, don't tell Trig anything. He would have it all apart again by now to see what the problem is  :'( :'(
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Offline Orcade-Ian

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Re: Cylinder stud too short!!
« Reply #21 on: February 19, 2018, 04:23:19 PM »
Just checked the barrel height and it’s 67.4 mm plus a gasket at about half a mm means that you should have 100 - 68 or about 32 mm sticking up above your barrels.  Didn’t get to put the barrels on the case - too many bikes in the way!

Ian

Offline Fogdevil

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Re: Cylinder stud too short!!
« Reply #22 on: February 19, 2018, 04:42:04 PM »
The dowel is straight but the stud is 'not quite vertical'.However, once the cylinder head is on there is no problem and it is very easy to get it on.

There is no washer lodged anywhere but the offending stud is 5mm shorter than its equivalent.

I will tentatively try the double nut method(I only thought of using a stud extractor which would have caused damage) and if there is any sign of success I will take the stud out, measure it and then replace with new.

I suppose the double nut method can be reversed to tighten studs up and a torque wrench used on the upper nut if needed?

Just measured the stud heights above the barrel 28.4mm and 23.6mm

Offline Nurse Julie

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Re: Cylinder stud too short!!
« Reply #23 on: February 19, 2018, 04:46:58 PM »
So it's the wrong length stud, what a pain but easily sortable. Yes, you can double nut to get a stud tightened up again. Well done, you got there in the end.
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Offline K2-K6

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Re: Cylinder stud too short!!
« Reply #24 on: February 19, 2018, 04:57:13 PM »
As I understand it the studs shouldn't be torqued into the cases (please correct if anyone has proof to the contrary)  it looks like Honda put them in with semipermanent/heatresistant/never-come off-till-you're-dead, thread lock, which is why they are Sooooo very hard to get out.

My view would be they should all be thread locked to avoid them backing out in service.

Offline Nurse Julie

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Re: Cylinder stud too short!!
« Reply #25 on: February 19, 2018, 05:34:17 PM »
You are correct Nigel, the studs should not be torqued, just 'nipped' up. There is no torque setting for them in the manuals. Trig says there is no thread lock or similar used on the studs. I think they are so very tight because of the corrosion and they are somewhat 'springy' when you try to turn them to get them out.
If Foggy measured the studs before putting them in and they were all the correct length, this can only mean that a stud has broken through the casing by 5 mm, so may need investigating further when he gets the stud out.
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Offline Fogdevil

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Re: Cylinder stud too short!!
« Reply #26 on: February 19, 2018, 05:52:18 PM »
Thanks everybody.

This morning I was hoping I could do an easy fix/bodge but you have all convinced me that is not the way to go.I need to get the stud out,examined and check for any damage below.

It is a right royal pain but hey-ho.I've absorbed a lot of info and learnt new tips.

I will let you know how I get on.

Cheers   Foggy

Offline K2-K6

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Re: Cylinder stud too short!!
« Reply #27 on: February 19, 2018, 05:53:39 PM »
Yes,  that was my fear as your first post pointed out. If it's the correct stud and the case is damaged, it's certainly a different problem.

I suppose it's not included in manuals as it's generally not a serviceable routine to remove the studs. When I've removed them I've been convinced that the dry powder that comes out is thread lock though. The design seems to call for that from an idealistic point of view, and they never ever release when undoing the head bolts as far as I've found. I just don't think you'd get that consistency if it was plain corrosion.

Fingers crossed that it's an odd stud and no damage done.

Edit,  I was responding to Julie and my post came in after yours Foggy.
« Last Edit: February 19, 2018, 05:55:29 PM by K2-K6 »

Offline Orcade-Ian

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Re: Cylinder stud too short!!
« Reply #28 on: February 19, 2018, 05:54:38 PM »
I find it difficult to believe that a correctly dimensioned stud - length, diameter and shoulder could be forced into the crank case top accidentally, especially by an engineering company worthy of the name.  Hope it ends with a good result with minimum effort and cost.

Ian

Just noticed you are in Chorley - are you a Central Lancs VJMC member by any chance?
« Last Edit: February 19, 2018, 05:57:49 PM by orcadian »

Offline Nurse Julie

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Re: Cylinder stud too short!!
« Reply #29 on: February 19, 2018, 05:57:12 PM »
Yes, fingers crossed for an easy, swift outcome Foggy.
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