Cylinder to case gasket fail

[peanut]

it may be rocket science lol but keep in mind that none of us have NASA torque wrenches
most of ours are unlikely to be regularly calibrated or accurate to within +- 5-10lbs

 

[thuban]

it may be rocket science lol but keep in mind that none of us have NASA torque wrenches
most of ours are unlikely to be regularly calibrated or accurate to within +- 5-10lbs

Torque wrenches...Don't get me started! I just threw a "new" one in the shit can! It was cheap and I did not trust it! Someone will fine it and say, "Hey, somebody accidently threw away a brand new torque wrench!" Then he will break a bolt off and somebody else will fine it!

 

[jetmechmarty]

it may be rocket science lol but keep in mind that none of us have NASA torque wrenches
most of ours are unlikely to be regularly calibrated or accurate to within +- 5-10lbs

It' should be close enough for what we're doing. It's a lot more accurate than adding lube where it isn't supposed to be. Just keep it in mind when lubing stuff up. I admit I'm also a fan of anti-seize.

I once snapped off a bolt as a NASA contractor, while working on space hardware with a NASA torque wrench. Shite happens. Sometimes it's real expensive.

 

[jetmechmarty]

I once worked where I had easy access to torque wrench calibration. I tested my cheap torque wrenches. All were dead nuts exactly correct precisely in the middle of the scale. At the ends of the scale, they were off by the advertised 4% or whatever it was. Tight on the low end, loose on the high end.

 

[peanut]

Torque wrenches...Don't get me started! I just threw a "new" one in the shit can! It was cheap and I did not trust it! Someone will fine it and say, "Hey, somebody accidently threw away a brand new torque wrench!" Then he will break a bolt off and somebody else will fine it!

I know ....I have 2x and I don't trust either of them . Where do you get your torque wrench calibrated ? who bothers anyway ...
After 50+ years many without a torque wrench I rely on and trust my muscle memory more than any torque wrench for simple auto stuff and the odd rocket or 2

 

[peanut]

I once worked where I had easy access to torque wrench calibration. I tested my cheap torque wrenches. All were dead nuts exactly correct precisely in the middle of the scale. At the ends of the scale, they were off by the advertised 4% or whatever it was. Tight on the low end, loose on the high end.

blimey !... well that IS a surprise

 

[Jim]

I once worked where I had easy access to torque wrench calibration. I tested my cheap torque wrenches. All were dead nuts exactly correct precisely in the middle of the scale. At the ends of the scale, they were off by the advertised 4% or whatever it was. Tight on the low end, loose on the high end.

Same here. For about 6 yrs I worked at a place that gave easy access to cal. equipment. All my buddies gave me their wrenches to check. The cheapo's were every bit as good as the expensive one. Even the beam type were accurate.

 

[Jim]

Homemade torque wrench checker: Clamp a bolt in your vise. Attach a fish scale midpoint on the wrench handle. Set your value and pull. Click should agree with the value on your pull gauge (fish scale). Accuracy is as good (or bad) as the accuracy of your pull tester.
EDIT: There's a little math involved.

 

[grizld1]

2M has already posted a copy of the Yamaha service bulletins that specify lubricating the engine studs with motor oil and periodic retorque. Assembly grease works well too. I've followed those factory recommendations for decades with no regrets. The main cause of pressure loss between head and barrels is the rubber covered washers that Yamaha used on the four outside studs. Pressure (indirectly measured by fastener torque) remains far more steady if the rubber covered originals are replaced with copper washers. A quick search will turn up the number of a Suzuki part that works beautifully. To quote Rabelais, "Do as thou wilt."

 

[Jim]

I was giving thought to making a quick video on how to test your wrench when it dawned on me..... it's prolly already been done a hundred times. So... over to Youtube... yup, it's been done. Here's a pretty good one.

 

[jetmechmarty]

Yep. I took us on the side track over torque values. It seemed important enough.

 

[thuban]

I was giving thought to making a quick video on how to test your wrench when it dawned on me..... it's prolly already been done a hundred times. So... over to Youtube... yup, it's been done. Here's a pretty good one.

That's cool beans! But It would have been interesting if he had tested a lower and higher setting on each wrench after cal. We know the wrenches are more accurate in the middle of their scale. There in lies the problem. The 1/2 inch drives start off at about 20 lbs bottom of their scale and when your final torque is 27 lbs., they might not click over and you strip the stud or nut. It's not the wrench for the job. The inch pound, 3/8 drive is middle of it's scale for the bolts at 14ft lbs (168 Inch lbs) but at the top of the scale at 27ft lbs ( 324 inch lbs) Probably ruin the wrench. It's hard to find a good wrench that will cover the torque ranges on this head. So I use two different wrenches. I didn't just trash my cheap wrench because It didn't want to give a "click" at low torque, ( My bad) I tossed it because sometimes it wouldn't click torqueing a John Deere head bolt! That is BS so...
My cylinder base gasket quit moving after the third torque. 100 miles and still holding fine. Got out the exacto, and like others, trimmed the excess off. This is the first time I've seen a gasket of this type exhibit "Cold Flow".
Thu

 

[gggGary]

I was giving thought to making a quick video on how to test your wrench when it dawned on me..... it's prolly already been done a hundred times. So... over to Youtube... yup, it's been done. Here's a pretty good one.

How do I calibrate my luggage scale?
He's calibrating a $100 wrench with a $7 scale LOL
I did the same thing when I bought a big box of used snap-on torque wrenches.

 

[Jim]

How do I calibrate my luggage scale?

Pick up an object of known weight... compare values.

 

[thuban]

I gota say, a gasket that is steel in the middle and Viton on each side is not gona flow, or stick to the cases and not gona leak. I've done my part of trying to separate stuck cases. I have the Viton gaskets on both side cases. Case sides come right off in your hand. No messy gasket sealer or grease. A precession crush at torque each time. I reused the clutch gasket during the head rebuild. No leaks and as solid as the first time. I'm sure somewhere around here, is a post that describes an easy way of getting the yama-bonded valve cover off the head. I haven't seen it, so I "re-discovered" an easy way to free the valve cover without cussing and prying. (after the nuts and bolts are off) tighten up each valve adjuster a little at a time, evenly. The valve springs will pop the cover off.
Seems so simple now.

 

[jetmechmarty]

Funny thing is........An experienced mechanic can be given 8 (or pick a number) nuts to torque down to a given measurement WITHOUT a torque wrench. Normally, they will be within a few lbs of that spec, but more importantly, they will all be virtually the same torque.

I might like to think I can do that.