Top End Rebuild

Mikesxs · Full Member Joined: Feb 06, 2007 Posts: 134 Location: FL

Athena Head and base gaskets are chemically treated (ours) and should Not have gasket cement applied. Retorque top end after engine gets hot.

Mike Lalonde Mikes XS

jimmer · Posted: October 20, 2008, 6:26 pm Post subject: Re: Top End Rebuild

Mikes gaskets work great now. No leaks here using no sealer. Hylomar is great for metal to metal only. Don't use Hylomar on gaskets ... they just 'slip/slide'.

Jake68 · 650Rider Supporter Joined: Mar 23, 2007 Posts: 841

Yes this is happening to me...

What occurs I think is that the studs stretch and then bottom out in the dome nuts.

y recommendation is to rebuild using large plated washers the type that Mikes sells on each stud and use deeper stainless steel M10x1.25 nuts to avoid this.

They also make a much better mating service against the crappy rubberised sealing washers.

Also, get the head checked for deck deviasion have it skimmed as little as possible if you need to.

This is a more common problem than XS users think it is...I have the problem after two top end tear downs and the bike runs pretty good too!.

ike is so right...imho sealer will break down with heat and make it leak worse!

5twins · Full Member Joined: Aug 05, 2006 Posts: 1616

The gasket sets I've used were his old style ones without the chemically treated gaskets. With those, it was common practice to use sealer on the base gasket. None of the ones I've done have leaked (yet, anyway).

For the head gasket, we're not talking about totally coating the thing. Just a thin, narrow bead around the cam chain tunnel and 4 outside oil flowing stud holes applied with a toothpick, both sides of the gasket. If I do use any of his new head gaskets in the future, I will probably still add this small amount of sealer just for my own peace of mind. Many factory head gaskets come this way, with a ring of sealer pre-applied, both side, around oil flowing passages.

Jake68 · 650Rider Supporter Joined: Mar 23, 2007 Posts: 841

Where do those outer studs flow oil to and from?

Retiredgentleman · Posted: October 22, 2008, 1:25 am Post subject: Re: Top End Rebuild

The upper oil feed to the rocker arms and camshaft puts oil along the rocker arm shafts which is connected to the outer studs, so it appears that some oil drains back to the sump via those outer studs.
By the way, I did some clean up on those carboned up pistons:

xsjohn · Posted: October 22, 2008, 1:32 am Post subject: Re: Top End Rebuild

Dems some perty pisstons....

sorry just trying to get used to the elections here.........

xsjohn

5twins · Full Member Joined: Aug 05, 2006 Posts: 1616

Those cleaned up nice - don't mix 'em up now Smile

How'd the rings spec out? Valves? The exhaust valves are the usual leakers. They take more of a beating what with having to pass the hot exhaust gases all the time.

jimmythetrucker · Full Member Joined: Mar 12, 2008 Posts: 1283

I'm not sure valve seals are the whole story on that carbon. I believe I'd check and make sure the guides aren't bell-mouthed or in some other way wallered out.

Retiredgentleman · Posted: October 22, 2008, 12:36 pm Post subject: Re: Top End Rebuild

jimmy; Turns out it wasn't the valve seals and the guides look good too. As I mentioned in an earlier post, I found that the PO did not do a proper re-torque on the head bolts and oil was migrating across the head gasket. PO probably just torqued bolts once and walked away, as jayel said the other day, "dam those PO's" .

xsjohn · Posted: October 22, 2008, 12:43 pm Post subject: Re: Top End Rebuild

Don't know if I should ask.......did you try torquing the head before dismantle.....

When I put my head on I start with the center ones ...paranoi I guess....

xsjohn

Retiredgentleman · Posted: October 22, 2008, 1:30 pm Post subject: Re: Top End Rebuild

Didn't try re-torquing John. I knew the heads, pistons etc. were all carboned up and top end had to be opened up. Good thing I opened it up, the carbon was so thick (maybe .060" on valves and piston combined), there may have been contact between valve and piston Shocked

. The front cam chain guide was starting to have pieces fall off as well.

xsjohn · Posted: October 22, 2008, 1:43 pm Post subject: Re: Top End Rebuild

Think I woke up stupid today.....forgot about all that stuff.......xsjohn

Jake68 · 650Rider Supporter Joined: Mar 23, 2007 Posts: 841

It sounds stupid RG...but please try to get the decks checked and make sure the dome nuts arent bottomed out when you re-assemble?

I have the EXACT same problem and it wont go away!

5twins · Full Member Joined: Aug 05, 2006 Posts: 1616

And don't forget to swap out those funky rubber/metal washers under the 4 outside acorn nuts for copper or brass ones. The rubber ones cause those 4 nuts to constantly loosen up. Mike sells brass (I think, might be bronze) replacements or you can use the copper ones from the GS Suzuki fours. Some guys say they've found replacements at the hardware store but they must be thick enough. Check the thickness of the originals and you'll see. If you use too thin a washer, you might encounter the problem Jake mentioned with the nuts bottoming out before things are compressed enough to seal.

Retiredgentleman · Posted: October 23, 2008, 2:41 pm Post subject: Re: Top End Rebuild

Yes, I saw the copper washers at 650central, got to be better than rubber washers.

Jake68 · 650Rider Supporter Joined: Mar 23, 2007 Posts: 841

I used a mix of the original rubberised metal and nickel plated extra thick washers...

I think my problem is that I ran it without realising there was a problem with the dome nuts bottoming out..and this has caused the gasket to ruin and any subsequent attempts to fix it are a waste of time (again)..

you gotta get it to torque first and then retorque it..you cant have a failed torque level and a leaking gasket and hope to fix a big problem like that by correctly torqing afterward...

Oh...hindsight..if only I had a time machine..I would go back in time and punch myself squarely in the face as I walked away from the bike happy, not knowing the dome nuts were bottomed out Smile

xsjohn · Posted: October 23, 2008, 7:30 pm Post subject: Re: Top End Rebuild

Washers.......scrape the rubber off of the steel washers and put a lite coat of silicone on them.........doing that for years .....no problems...........
xsjohn

Retiredgentleman · Posted: October 23, 2008, 9:35 pm Post subject: Re: Top End Rebuild

Jake68;
Bottoming out on the dome nuts does not seem to be a problem for most re-builds. I'm just wondering why your engine would be different. Any chance the 8 long studs had been removed and then not fully installed, thus making them longer.

xs1961 · Posted: October 24, 2008, 1:19 pm Post subject: Re: Top End Rebuild

Good point Retiredchap, I've seen that before on a motor that had been bead-blasted & some of the residue was left in the stud-holes preventing the (long) studs being screwed all the way in !

weekendrider · Posted: October 24, 2008, 3:11 pm Post subject: Re: Top End Rebuild

What is the torque on the long studs at the case?
I've got some of the copper washers from 650 central and they aren't as thick.

yamaman · Posted: October 24, 2008, 3:19 pm Post subject: Re: Top End Rebuild

Can someone confirm this is right:

www.xs650.org.au/torqu...ations.htm

Jake68 · 650Rider Supporter Joined: Mar 23, 2007 Posts: 841

Its all possible RG..either that or they stretched...also possible

Or the Mikes/Heiden/XSshop top end kit has shallow nuts..

All I know is three owners with the same description of the problem!..

Just wanna get everything worked out...

yamaman · Posted: October 24, 2008, 3:49 pm Post subject: Re: Top End Rebuild

weekendrider wrote:

What is the torque on the long studs at the case?
I've got some of the copper washers from 650 central and they aren't as thick.

A better question might be what is the overall protruding length of the studs??????????????? Twisted Evil

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