Head Retorque and Brass Washers Question

[Solomoriah]

So I have oil leaking from the left side of my just-purchased XS650, specifically from the head gasket. It runs good, so no compression issue is evident. I saw this old thread:

http://www.xs650.com/threads/leaking-head-gasket.30135/#post-302298

The members there talk about retorquing the head bolts, which I have already been advised to try on my 1980 Honda CB650 which has a similar issue. I'm good with doing that, but the thread above is light on details, and I'm the sort who likes to have everything nailed down.

First of all, brass washers are mentioned, from Mike's XS. Is this the correct part?

https://www.mikesxs.net/yamaha-xs650-brass-cylinder-head-washer-oem-90210-10004-00.html

According to the parts fiche on CMSNL (which is the one I use all the time for my other bikes), there are 4 part no. 90210-10004 washers used, which according to Mike's XS are the equivalent parts to the brass washers they are selling. But according to the parts fiche, there are also 4 part no. 90201-10131 washers, under the other four acorn nuts. I don't find a replacement for that part... what exactly is needed here?

Incidentally, I did find this part: https://www.mikesxs.net/yamaha-xs65...0430-06014-90210-10004-00-90201-10131-00.html

It claims to be a "Bottom end" kit in the title, but it says "top end" in the description, so I'm more than a little confused.

Mainly, I just want to know what the procedure is before I start. I assume the nuts get removed one at a time, replacement washers fitted, and then retorqued to 30 foot-pounds for the acorn nuts, and the factory 14-16 for the other head bolts/nuts. Do I have this right?

Parts Fiche:
https://www.cmsnl.com/yamaha-xs650-1980-a-usa_model8759/partslist/A-05.html

 

[5twins]

Many of us are getting away from that increased 30 to 35 ft/lb spec we used to use on the 8 large acorn nuts, sticking closer to the factory spec (about 28 ft/lbs max). If you go much over 30, you run the risk of stretching the studs or warping some of the parts. Also be aware of the one small 6mm bolt at the rear, it only gets about 7 ft/lbs.

I use these Suzuki copper washers on mine for a couple reasons. First, the MikesXS brass ones weren't available when I did the swap and second, the Suzuki washers are cheaper .....

https://www.partzilla.com/product/suzuki/09168-10017

I've since found even cheaper generic ones on eBay .....

https://www.ebay.com/itm/20Pcs-Copper-Crush-Washer-Flat-Ring-Gasket-Fitting-10mmx22mmx2mm/231479115961?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

You only need the softer copper or brass washers on the 4 outside nuts because they flow oil down their studs. The 4 inner acorn nuts and studs are dry so the original plain steel washers are OK there.

Yes, remove one at a time, clean and lube the threads (anti-seize), then torque. I bring them up to about 25 in a couple steps, then once all are done, go back and bring them up to 28. The only other bolts that contribute to sealing the head gasket are the 2 under the spark plugs and that little 6mm at the rear. The other smaller bolts in the top cover only hold that cover on. You probably don't need to disturb those.

 

[Jim]

I found copper washers at my local Ace hardware for less than a buck apiece.

 

[Superjet]

5twins I did my cam chain this spring and went with the 30 to 35 range on head torque. I wasn't aware of sticking with a max 28 spec. Any threads about this discussion?? I would like to read up on it. J-C

 

[Jim]

I go to 27ft-lbs. You can read my thoughts on it here at the bottom of comment #3.

 

[5twins]

I don't recall any threads specifically, but it's been discussed in a few recently. Maybe do a search for head bolt torque.

 

[Solomoriah]

5twins, thank you for the details. Now I know what I need, I can get this job done!