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Alan Glasser
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1981 Yamaha XS650H Engine Overhaul
13, 380 miles - Started June 29, 2004 - Completed July 19, 2004
On June 7th I completed a round trip to AMERICADE (A Touring Bike Expo) in Lake George, NY. I heard some strange engine noises that I knew were not good. I knew I had timing chain damper issues but this was more. So I asked the XS650 Society too see what they might come up with.

On June 24th I sent: 
I know I am not going to get a good answer but I have to ask. My  13,000-mile motor developed a bad bearing noise. Most noticeable from the transmission area. I can "feel" it on the kick-start lever. Sound doesn't change with engine speed or shifting the gears. Engine runs fine, starts fine (kick and electric start) sounds like shit. Pulling the sump, there is some (but not a hell of a lot) very small (less then 1/64 inch) bits of ground up shiny metal. Question it something you guys know from past experience such as a bearing that can be fixed from the right side cover? Or am I going to pull the engine and pull the cases apart? I thought these engines were "indestructible!?" I think I am going to have to write an essay "How I spent my summer vacation rebuilding my motor." Any ideas?   :-(((((

I received many helpful answers and suggestions.
The following is the story:

When I pulled the sump I found the sump screen with the typical blown hole in it and completely covered with sludge; I knew I should have changed the thing when I purchased the bike at 6,000 miles. You need to know something here. I baby the bike. More oil changes than necessary. Marvel Mystery Oil in the gas for the top end. Premium gas. Maybe over kill but for a 23-year-old bike it makes me feel better. So why didn't I change the sump filter??? Because when I went to my local trusted YAMAHA dealer to order one he said, "you don't have to touch that, just change the right side oil filter." Yeah, right!

There was also the shiny metal. Not aluminum from the front cam chain follower, but magnetic shiny metal. I knew I was in trouble. The engine had to come out for an overhaul.

I took the engine out buy myself with the help of a hoist. Moved the engine onto my workbench and proceeded to inspect it from the top down. Engine rebuilding is not new to me. I am 56 now but have rebuild car engines in the streets of Brooklyn during my teenage years. So this should be a piece of cake? Right? Well, maybe something like a bagel. It wasn't a piece of cake!

The top end looked good! (I will blueprint the engine later as best I can.)

I opened the case halves. Don't forget the case nut on the right side above the starter gear. I was doing some head scratching before I found it.

Well, I found the trouble…the front cam chain follower black plastic had come apart from the aluminum holder and lodged against the crankshaft. The crankshaft was grinding up the black plastic. The black plastic got into the right center crankshaft bearing. Probably blocked the oil from getting into the bearing as well. The bearing failed. The metal flakes from the bearing went though the sump oil filter (because of the hole) and from the holy sump filter into the oil pump. I found the outer rotor of the oil pump cracked (most likely from shards of bearing metal passing through the pump). Fortunately, the right side filter caught the remaining shards of main bearing roller metal and prevented a major engine catastrophe.

If you have never changed your sump filter DO SO NOW!
As I broke down the engine I used the digital camera to take many pictures and zip lock plastic bags to keep the different engine area parts in some order.

Once the engine was apart I put together a parts list and purchased the following items from Mikes XS.     Got the stuff in two days! Great service.
1. Complete gasket kit
2. Complete oil seal kit
3. Copper washer set for the top end.
4. Sealing washers for the four cylinder head acorn nuts (I know some people don't like these.)
5. Some extra gaskets (for future oil changes and side cover removal.)
6. Two crankshaft inner main bearings.
7. Front cam chain follower.
8. Rear cam chain tensioner arm.
9. New Cam chain.
10. Three bond non hardening gasket maker stuff.
11. Other odds and ends.
I located a crankshaft rebuilder in Florida. There were many helpful suggestions from members of the XS650 Society on how to do it myself, but Falicon Crankshaft Components, Inc. in Clearwater, FL.  did the rebuild in three days!

Got the oil pump from Speed and Sport in Bloomsburg, PA. (Mikes XS didn't have the oil pump rotor assembly only a new high volume pump.)

Ordered matching YAMAHA OEM silver engine case paint from PJH Brands in Scottsdale, AZ. I think you can find their web address searching on "PJ1" They are also part of VHT products.

Purchased lots of other "stuff" like spray on gasket remover, paint remover, cleaners, engine paints, oils, engine assembly oils, like I was building a spaceship!

I purchased a set of cloths dryer vent hose clamps to use as piston ring compression tools. Worked like a charm! Wish I took a picture but nobody was home to take the picture as I fit the cylinders.

I blueprinted the engine the best I could using micrometers and dial indicators. Everything was within specifications so I didn't bother with new valve guides, pistons, and cylinders. Heck, even the clutch had plenty life in it.

I  honed the cylinders.

I bead blasted the head and sprayed it with VHT 1200-degree clear coat.

I sprayed the cylinder and rocker arm cover (tippy top of the engine) black 550-degree black engine enamel.

I lapped the valves by hand like we used to do in the old days.

Cleaned out and checked all passages and bearing oil holes and oil squirt holes over bearings and gears.

Polished and/or cleaned every nut and bolt, side cover and piece of aluminum on the engine. I even used a "Q" tip inside the oil site hole on the right engine cover. I polished the end of the kick start shaft because it didn't look right sticking out of a shinny right side cover.

Installed new seals everywhere.

Assembled the engine.

Filled it with oil, primed the oil passages, used assembly lube, and ran it on the bench (starter only!) to make sure everything turned and sounded right.

Prepped the frame of the bike so I wouldn't damage it putting the engine back in. My son helped with the installation of the engine. Not a one-man job even with a hoist.

It started up on the third try (needed to get some of that oil out of the cylinders and gas into the carbs). Sounded sweeeeeeeeeeeeeeeeeeeeeeet! Better than I ever heard! Let it run for a few minutes and checked around. Nothing leaking! Nothing burning! No bad sounds. Started up again, and shifted through the gears. Sweeeeeeeeeeeeeeeeeet! Put two electric fans in front of the engine and let it run for about an hour switching gears and changing throttle speeds.

Next day I took if for a 90 mile ride. Sweeeeeeeeeeeeeeeeeeet!

Total cost to overhaul about $750.00. This was an overhaul not just a repair.
Total time to overhaul…way too much! Should be a winter project. Much time in polishing the cases, nuts, bolts, etc.

Maybe you would have done it different.

"But I did it my way."

My thanks to:

My wife for putting up with the mess, smells, and me baking parts in her oven. (And the washing of parts in the dishwasher, but she don't know about that).

My son, and his back. (He owns a 2004 HD Road King Classic. Knows nothing about wrenching, so this was good experience for him.)

The many XS650 Society members who responded to my e-mails and added their knowledge.

Mike Lalonde.

Michael "Mercury" Morse.

Bob Bertaut

Jean Aker's web site.

A picture is worth a thousand words and I am tired of wording…so here are a few pictures:

NOTE: Click on the below pictures to see larger images.   Back button returns you here.


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