Head bolt order

[Incubus]

Is there a diagram on the site somewhere that shows the correct order for the tightening (loosening) of the head nuts? Thanks, y'all.

[strom]

Untighten... no order.
Tighten... inside near the camchain, back left one first, then on the opposite inside front right, left front, right back.... in a X pattern. Tighten to 2 kgm first, then in the same order to the spec. I torqued mine to 4 kgm.

LP

[TopCatGr58]

Not that I'm aware of!! It is highly recommended to acquire a manual, either Yamaha...rare, or Clymer's to assist you in the more detailed info you'll need for a rebuild! The Clymer's are readily available, thru Ebay, Your local bike shop, JCWhitney cycle catalog, etc.!! They are usually around $25.00, well worth the $.

RokJok also provides a CD for around $10.00, which has several models parts fiche, plus a manual, and proceeds go towards this site!
T.C.

[TopCatGr58]

You'll have to Xcuse STROM, he's EUROPEAN!!!

Now folks in Oklahoma have tried to torque them to only 14lbs, but the head leaked!! **That's a joke, right TODD?**

In TEXAS, you'll want to torque to 14lbs first time thru, then to 25 for that last round, Xcept for the two NUTs right in the middle, one in front of head, one in back of head, they are only 14lbs!

This is the type of info and more that's IN THE MANUALS! hint,hint.
T.C.

[Incubus]

I actually have ordered the manual already. I always get one for a rebuild, even if it's a fairly familiar model, which this one is not. Only did one Yamaha before and it was a one-cylinder DT1. This is a bit more complex. But I only got the bike yesterday and I hate to waste a weekend, so I figured I'd take it apart as far as I could today. Where are the pry points for this head? I took off all the nuts, including the ones in front and behind the head, and still the head desn't budge. I've already found enough to convince me that this bike has been taken apart before and I fear that someone sealed the top end with some type of gasket glue crud. I've pounded with my rubber hammer until my hand went numb and still nothing.....

Any suggestions?

Thanks,

Pat

[TopCatGr58]

Hey Pat,

The pry points per the manual is ANYWHERE the fins are reinforced with the vertical ribs!

Probably stupid question, but have you been able to remove the cams? With the engine frozen, it's tough to be able to rotate the cams around to be able to get to BOTH of the sprocket bolts that secure them to the cams!? Removing the cam chain tensioner will get you some slack. Then you can possibly slide the chain up over a sprocket, then you can remove the cam bearing caps, and lift the cams straight up WITHOUT ROTATING them! Don't forget to stuff rags down the cam chain well so you don't loose the small bearing cap nuts/washers down there!

Another thing you might try is putting a wooden handle inside one of the exhaust ports and try prying up with that!?

The cylinders can develop a lot of corrosion around the head studs where they run exposed on the cylinders, so check for that before you try to remove the cylinders!
Good Luck! T.C.

[mro]

Heads Up!

I use a 1 1/2 wide X 3/4 inch thick X 8 inches long piece of wood. One end I notched to (about 1/4 inch thick) fit better under fins. Allows me to rap on it pretty good.

Once it moves I put a flat scraper between head and cylinders to keep it open and then go to other side. Need to try and move head or cylinders up evenly. Not a good idea to pry between head and cylinders with screw driver.

Removing cylinders, there are reinforced spots just above motor mounts in front and I got lucky that a pry bar I have just happens to fit in there real good.



mro

[skids]

Double check to make sure you got all of the nuts. There are some that are well hidden in the inside spark plug areas...

Originally posted by Succubus
Where are the pry points for this head? I took off all the nuts, including the ones in front and behind the head, and still the head desn't budge.

[trbig]

Man.... I was wondering how long until I took a public ribbing on that one. As you can see from the picture, it was an honest mistake!! After fighting and cussing the thing for hours... you glance at the book and see this....



Oh well.... bring it on TC... I can take it! * sniff sniff... lol.

This is the tightening sequence shown in my XJ book... can't verify if it's the same for the XS, but would think so. Like TC said, tighten to 14 ft. pounds first go around, then 25.


Tod

[Incubus]

I found all 12 of the nuts by the plugs and the ones in the front and the back. I also managed to lift one side enough to get a knife in the crack and found.... clear sealant. Why do people use stuff like that when a thin coating of grease on the gasket seals just as well and makes disassembly a breeze. The head will not break free. I'm thinking it may be time to get out the propane torch and see if I can burn the gasket and sealant off...... I have tried everything y'all suggested. When I rebuilt my Honda CB40oT a couple years ago I managed to pound the head off, but I had to pull the engine and lay it on its side to get enough torque on the rubber hammer. I was hoping to avoid pulling this engine because: a it's huge, and b) the tranny appears to be in working order so I didn't plan to split the case. My plan may need to be revised a bit......

[strom]

AFAIK there is an oil line running behind the cylinders. Dont forget to take it off.
And dont brake the fins... the PO on my 78E did.
And I sure hope you took the camchain off.

LP

[Incubus]

I found the oil line and took it off. I had to cut the cam chain. It wouldn't loosen enough to get it off the sprockets and the sprockets wouldn't turn. I would have replaced it anyway, what with the engine apart and everything. I think the PO just glued everything together with silicone or something. If I pry around the sides I can lift it enough to get a crack, but it won't let go. I assume there are also positioning dowels in there somewhere and I've known those to corrode up pretty good, but usually they break free with a few hammer blows. This is always the hardest part of a dismantle for me.

Pat

[mro]

Had a real battle getting first head off.

On a couple others, I start the day before and spray liquid wrench (several times and use about 1/4 can total).

Corrosion and road debris clog around studs and liquid wrench seems to work best for loosening it up.

btw, did you tie up the ends of the cam chain or did it fall in to the crank case?



mro

[Incubus]

Cam chain? In the stupid case. I'll have to fish out the ends later. I've had to do that before. It's not fun, but it can be done. I also sprayed liquid wrench around the studs before I started working on it. I can actually move most of them a bit in the holes, so I am thinking that's not where it is binding. There will be more poured into the holes today. And when I think, this is just the head. I still have the issue of a frozen motor and the cylinder block. My guess, before I get the head off, is that one or more ring sets have oxidized inside the cylinders and rusted tight. At least I hope that is the case. It's a pain, but far preferable to frozen crank bearings.....

[Pat Kelly]

Originally posted by Succubus
I had to cut the cam chain. It wouldn't loosen enough to get it off the sprockets
Pat

Did you use a chainsaw for this?