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I searched the archives and was able to get some basic info, but I would like some real gearhead advice here. My '06 has the standard cylinder base oil leak. It is pretty much just heavy seepage and has not gotten worse in 3000 miles. I will eventually replace the gasket but for now I want to re-torque the head bolts. My question is should I just crank them down to 16 ft/lbs ? My thought was to back them off first, then put a drop or two of light oil (3 in 1) on the threads and then bring them up to spec. My idea is to reduce any parasitic friction and get a more even / accurate pull. Am I asking for trouble and/or wasting my time ? I believe I just have one shot at this to fix or at least reduce the dad-gum leak. Your opinions and recommendations are greatly appreciated!



thank you kindly
 

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My mechanic buddy says to torque (in proper sequence) to specs without backing them off. He says the head is already "seated" and backing off the head bolts "MAY" change the seat. He emphasized to make sure and torque them in sequence.



He also mentioned that unless the head bolts are already loose, re-torquing may or may not really help.



Just a note: for the record, my 2005 has never had this cylinder leaking or seepage problem.
 

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Never oil threads before torquing down unless specifically instructed to by the manufacturer.


I was taught never to torque any bolt without some kind of oil or assembly lube on the threads!

The Yamaha service manual indcates the use of "engine oil" on the threads for this application.

Anyhoooo....I just replaced the base and head gasket on my 08 last weekend.

After looking at how badly chewed up the old gasket was, there was no way anything other than

replacement would cure the leak. It appeared the gasket material itself was crumbling.

It was a pretty easy replacement, took a couple hours, going slow and sure.

Just be sure the timing sprocket index mark lines up EXACTLY were it was (ask me how I know)

Runs like a top now, 300 miles break in so far, no leaks.

Waiting for parts for the wifes TW to arrive to do it all over again!

Don't waste your time trying to torque anything, just replace it.

Also check the timing chain guide for wear! mine was wearing poorly and was tossing bits of black

plastic into the motor!

Good luck.

Igofar
 

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My mechanic buddy says to torque (in proper sequence) to specs without backing them off. He says the head is already "seated" and backing off the head bolts "MAY" change the seat. He emphasized to make sure and torque them in sequence.



He also mentioned that unless the head bolts are already loose, re-torquing may or may not really help.



Just a note: for the record, my 2005 has never had this cylinder leaking or seepage problem.


I've always heard to back them off to break them loose, then re-torque. And if you do this one at a time nothing should come unseated.



The assembly lube/oil should be applied as recommended by the manufacturer of the bolt, and torqued according to that manufacturer's specs. If yamaha says use oil, then use the oil and torque to what they say. If ARP says use their bolt lube then use their bolt lube and torque to their spec. Remember, torque is just an easier measurement to get towards the measurement that matters, which is bolt stretch. Different oils/lubes will alter that torque reading but you may or may not have the necessarily bolt stretch. Which might mean you should remove one head bolt at a time and check that it's clean of corrosion, otherwise the corrosion will throw off the torque reading as well.



My $0.02
 

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He also mentioned that unless the head bolts are already loose, re-torquing may or may not really help.
I think that is because when you torque a loose screw, the wrench is measuring the force while the screw is turning. If the screw is already pretty tight, static friction needs to be overcome before it will start to turn. The wrench will likely reach the desired torque reading before the screw starts to turn. So there is really no point in re-torquing unless you loosen first.



Just a note: for the record, my 2005 has never had this cylinder leaking or seepage problem.
At 6600 miles, my 2005 has never had it either.
 
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