Freshly assembled XJ550 motor blows up, help w/post mortem

I recently replaced the tired leaky 60K+ engine in my Seca with one I got from a local junkyard that had approx 10K on it. My cylinder head was recently rebuilt, so I kept that and got the crankcase, bottom end, and cylinders.

The replacement motor had been sitting for 25 years, and someone had pulled the starter, so dirt got into the crankcase. It was decided that it would be best to crack the case, clean everything up, and then re-assemble the engine. The cylinders were also taken to a machine shop and honed.

A mechanic friend of mine did pretty much all the re-assembly work, with me mostly watching and helping out on occasion. He insisted on doing most of the work himself because he "wanted to make sure it would get done right".

The last night of work, we only had 2-3 quarts of Dino Hondo and Spectro motorcycle, so that was put into the engine at first. We decided that we needed more oil, but it was late and Walmart was the only option. They did not have any Rotella 15W-40 so we got the 5W-40 synthetic instead.

The next morning he got the engine carbs and timing set, and the engine was running well. We both drove the bike around the neighborhood a few times keeping rpms below 5000.

I decided to take the bike down to the licensing agency. Got on the freeway, never exceeding 4k rpms, and 3.5 miles later right before I got to my destination, I lost cylinder #4. Restarted the motor to finish my left hand turn and then it died again. No sense in renewing tabs on a bike that might be toast, and I didn't feel like paying $60 for a tow so I walked the bike 3.5 miles home. Fortunately it was a nice day and a flat route.

The previous night, when the mechanic drained out the 2-3 quarts of dino oil, he found a metal fiber stuck to the magnetic oil plug. I'm guessing that it came from one of the steel polishing cups we were using to clean the carbon from the combustion chambers on the cylinder head.

So here's the rub. Obviously I'm pretty damn pissed that my motor was destroyed 5 miles into its very short life. He claims that it was because we used the 5W-40 Synthetic Rotella, that it was "too thin"

I spoke to a couple other of my motorhead friends who are knowledgable and have experience building race motors (automotive), and asked them what they thought about the mechanic's claim. After doing so I think that:

A) Hes probably full of s**t and just trying to avoid taking resposibility for effing up the job.

or

B) Has some serious gaps in his knowledge.

The consensus among my motorhead friends is that something got into that cylinder, either a small fiber or possible a nut or something was left in the intake port. It starting wearing away until the piston heated up and seized. They said that if something like a nut got sucked into the cylinder, usually you'll see what's left of it there sitting on top of the piston.

They also said that breaking in a motor with synthetic oil will not cause this type of engine failure, although it will take longer for the rings to seat. I'm not even sure if this scenario really qualifies as "breaking in" the motor, because we re-used the original rings from the 10k motor as they were in great shape along with the pistons.

Later that night when I got the bike home and into the garage, I pulled the heads to inspect the damage and took video and pics.

What do you guys think caused my engine to fail? It's important that I get to the bottom of this because he claims I owe him money. I feel that he should probably owe me money at this point.

Pictures:
http://www.flickr.com/photos/srf21c/set ... 429807255/
Video: (coming soon)

 

Re: Freshly assembled XJ550 motor blows up, need help w/post mor

The use of synthetics for engine break-in are recommended by Mobile and will not cause the damage you are experiencing. 5-40W is not my prime choice but it is by no means the issue. Your "mechanic" needs to get schooled. However, the base issue seems to be that something foreign got in there and mucked up the works. Who assembled the engine and who put it on the bike? IF it was the same person, you have your prime suspect. IF you installed it, odds are that you alone may be the culprit.
This is one of the primary reasons I and I alone touch my machines. I've learned not to trust anyone. One, because they do not know my machines to the degree of intimacy I have learned and two, they have not the same motivation to take the time and care to render all due diligence.
Get the engine opened up and find out what happened, then you can take your "mechanic friend" to task should his negligence become glaringly apparent.

 

Re: Freshly assembled XJ550 motor blows up, need help w/post mor

Oh yes, I'd love to poke my nose in there. Where are you, generally speaking?

 

Re: Freshly assembled XJ550 motor blows up, need help w/post

Thanks for your feedback.

I am in the Phoenix area, quite a haul from Ventura I'm afraid.

Please see edited post for links to pics and video.

 

Re: Freshly assembled XJ550 motor blows up, need help w/post mor

He did. That's why I think he needs to own up to destroying my engine.

 

^^agreed.

 

Wow, those are some rather large bits of metal within that cylinder!!

Have you been able to tell whether such bits of metal are:

a) parts of a ring (should be magnetic)
b) part of the piston (non-magnetic)

If it's magnetic, AND the piston itself is not damaged, then it's probably a bolt or nut that somehow got in there.

Also, was the arrow on the piston facing towards the front of the engine?

If those are parts of the upper ring, then it should have also destroyed part of the piston also, so there might be a mixture of mag and non-mag material in there (as well as parts of the cylinder wall, which would be magnetic).

It almost looks like a ring seized, which could be caused by a number of issues.

 

Your "mechanic friend" left something in the system. I'd have it on his doorstep ASAP and give him the opportunity to make it right. Not too much damage (you were wise to shut it down and walk), it shouldn't set him back to much to straighten it out. Sure looks like he left a cotter pin behind...

 

That set of jugs is going to need to be replaced or a new cylinder liner inserted..............

 

was going to say it looks like part of a torx bit? or allen key? have him check his tools and let you know whats missing. Holy Crap!

 

Holy metal in the engine Bat Man. Something big was left in there. That cylinder is shot to $h1t.

I feel so bad for you. I'd be at the maximum height of pisstivity. You're taking it way better than I would, especially if he had told me I still owed him money.

FYI
synthetic oil did NOT do that damage. I run Lucas synthetic in my bike. He's fuller of you know what than a Christmas goose.

 

definitely magnetic bits of metal and based on the shape I'm pretty sure it's piston ring material.

Have not pulled the cylinder off the pistons yet, but at this point I don't believe that a bolt or nut was the cause. I think it was steel wool or brush particles, as there was already firm evidence of this on the oil drain plug.

Yes, the arrow was facing toward the exhaust as is proper.

I'm thinking a ring seized too. Another guy who looked at it in person said it appears that the siezed piston actually pulled cylinder sleeve down, that why you see the gap near the top.

 

yeah. Something was in there and beat the crap out of the top of the piston and combustion chamber (look at the damage to the head around the valves) before a piece was finally small enough to get down in there and seized the piston.

At this point I'd have this dipstick buying you another scrapyard motor. FIXING this one isn't cost-effective at this point. This schmo should do ALL the work for free, with you VIDEOTAPING every second.

It really sucks. I'm with Robert on this being reason #1 for not letting other fools work on your stuff. Even if you're "breaking new ground" so what if it takes you three or four times longer than it should; you're going to double and triple check. I'm always highly suspicious of those who claim to know it all; the only way to be 110% sure it's done right is to do it yourself.

 

Sorry posted before I read your latest. The beating very well could have been done by pieces of the RESULTS and not the cause.

Everything else I said still stands.

 

That's what I think but he refuses to own up to it.

This incident was the last straw. Suffice to say he's no longer my friend. Told him to take a hike and that I didn't owe him anything considering the $$ money he lost me that I already put into this engine.

Even if we did remain friends, I'd be reluctant to trust him to work on anything of mine after this fiasco.

Hopefully with the support of forum members and the miracle of photo and video technology, I'll be able to handle this myself.

 

Re: Freshly assembled XJ550 motor blows up, help w/post mort

Okay, and again, it's hard to tell in your photos, but if it's pieces of the RING that are THAT large in there, then it would have also HAD to have torn up the ring land area on the piston to migrate (in such large, unbroken pieces) from the ring groove up to the top of the piston.....and I didn't/couldn't see any real damage to the piston crown outer circumference to allow that much ring material to get "up there" without having a somewhat substantial sized chunk of piston material missing to allow such migration...............

 

Yeah, I'm going to see if I can find another set of cylinders and matching pistons in good shape from the same junkyard. They have about a dozen XJ550 secas there.

I'd actually like to start a different thread that discusses what my options are for getting out of this mess. Other than pushing this bike over the rim of the Grand Canyon. The thought *has* crossed my mind. :twisted:

If only you guys knew what I've been through with this motorcycle..

 

Like I said, I would just look for another motor. They're out there, and not impossible to find; fixing this one may get expensive or just be downright impossible. Finding things like pistons and rings for these bikes isn't always that easy.

 

And unless it was just a whole, HUGE amount of steel wool or burnishing brush filaments, I'm not so sure those would have caused that type of damage, either.

Again, just curious how such (relatively) HUGE chunks of metal got up on top of the piston crown.

Also, and I'm ignorant in this regard, but even IF the ring seized, could it really have actually "moved" and removed that much material from the very top of the cylinder wall? Normally there is a "wear ring" or build-up ring where the top ring stops it's upward movement along the sleeve,a nd this point is normally 2-3mm (or more) below the top edge of the sleeve; in the phoots, it looks like the entire top edge of the sleeve was damaged.......

 

Oh, yes, we so do. Don't go there.

Moving on; keep us posted and if there's anything we can do to help, well... you know that's why we're here! You're lucky you have a local scrapyard with some "raw material" this might not be impossible after all.

 

Thanks, it was pretty hard to accept at first, but I'm dealing. Hey, it's only money right? and time, and energy, and....

That's what the consensus certainly seems to be. It really makes me angry that he tried to fool me with that story. Thank god for you guys and the xjbikes.com forums!

My crap detector was certainly going off when he told me that.

 

I agree, but getting any money out of this person would be next to impossible and certainly not worth the aggravation and effort from my standpoint.

The crazy thing is that in his mind I still owe him money. He wanted $500 for pulling the cylinder head of my focus and doing this motorcyle "work".

What was supposed to be a one week job according to him took over two months and now my last set of wheels is toast. I have two other cars that need major engine work, and I have to move out of this house at the end of the month.

So I told him to go pound sand because he really put me in a bad spot.

Best just to sever ties and never deal with him again.

I have certainly learned the "If you want somethin done right, do it yourself" lesson the hard way in this particular instance.

The situation seemed hopeless at first until I decided to get on the forum and see what you guys had to say. You don't even know how much I appreciate all of your helpful comments and support.

I was about ready to give up, but I'm much more optimistic now knowing that I have you guys in my corner.

 

Re: Freshly assembled XJ550 motor blows up, help w/post mort

Good point. maybe it snuck through the gap created when the cylinder sleeve got pulled down?

 

Yes, pistons and rings are very hard to find, and if you do, they are big $$.

 

But wait, I thought I was SPECIAL. :mrgreen:

 

Ask rpgoerlich what he went through finding a set of stock pistons and rings for an XJ550.

And why do you think my '83 is named "Toxic Asset?"

 

You Can handle it you will need a manual. Man thats a serious bummer. On the oil issue I actually switched to the 5-40 synthetic rotella early this spring when it was about 25-30 *F out as my bike is my only mode of transportation. I have put well over 500 miles on the bike(work is only 2.5 miles away) even have had er revved up to 10K gettin into it with abosolutely no problems. The bike shifts smoother than with the 15-40. That being said I will be changing to the 15-40 or similar(May stay synthetic) when the hot weather starts to stick around. ALthough that may not make sense since the higher 40w is the viscosity of the oil when warm so ti really shouldn't hurt anything.

 

Re: Freshly assembled XJ550 motor blows up, help w/post mort

Shelly over at Speed and Sport should have 2 new pistons that I had returned to him once I found a set here locally. I got lucky and found a set after looking for a while.
There seems to be a couple cylinders with pistons on Ebay right now.

1981 Yamaha XJ550 Cylinder (s) / Jug (s) & Piston (s)

Yamaha XJ550 cylinders 1981

 

I don't suppose the guy might have not spaced the gaps in the rings properly when he put the jugs over the pistons. All the gaps at the same position would facilitate a non lubricated spot on one side of the cylinder, and maybe that melted/chewed the rings?

Just a thought, sorry about your experience bro, never fun to have an engine go like that, especially after you've just redone the hones etc.

I had a shadow 500 that we we did the valve seats, guides, cylinders rehoned, heads re shaved etc etc. Put it all back together and 2nd gear was screwed. I was so mad after all that time and money for the tranny to be weak.

 

The assembled gap is really about the size of the plug gap when running, or smaller, and rings spin very slowly while running.

I'll suggest a $200 tested "drop in ready" motor, and best of luck.

 

Hey srf21, I feel your pain. I found out after I bought my XJ650 that "it might need a valve adjustment" actually meant "it has cracked rings and some hard metal went through one of the cylinders". I felt like pushing it into Chesapeake Bay.

I got lucky though, and bought a really good running 750 engine for $99. I agree with the experts here (... I am not worthy...) that rather than tear your whole engine apart to check for bits of metal you just replace it. Maybe you'll get a good one like I did.

 

I've got the Clymer M387 manual as well as a 3-ring binder w/printouts of the manual on an XJ-cdrom from 7-8 years ago.

I was thinking the same thing, once the engine is warmed up, the synthetic oil should be the same viscosity/thickness as the dino multiweight.

 

Bummer. For some reason cliffs and bodies of water come into mind during episodes like these. If I lived in Hawaii I might also consider hurling it into the magma of an active volcano.

That's a great deal. If I could get a decent low mileage engine for under $200, I would be a happy camper.

 

Re: Freshly assembled XJ550 motor blows up, help w/post mort

Thanks for the links and suggestions. I'm going to pull the cylinders off today, and see what the piston and crankcase look like. My fear is that there will also be plenty of metal in the case, and I'm not sure if this motor is worth repairing. Such a waste after all the time work and $$ put into this one, but oh well.

I think the most cost and time effective route at this point is try and find another used motor as others have suggested.

 

Sorry Time i meant the spacing relative to each ring to eachother, not the "gap" in one ring end.

Like you would space them 8, 4, 12 o'clock between the top two compression rings and the oil ring.

If they were all 9 o'clock there would be a quick way for oil to shoot up to the combustion chamber, and a touch less compression, bad lube at 3 o'clock.

 

Re: Freshly assembled XJ550 motor blows up, help w/post mort

tried looking at your Engine Damage Photos but without success No matter.
Interestingly that motor as seen apart in the photos I did manage to see was Junk.. Is this the "new" motor from the Wrecker that was errr.. 'rebuilt'??
IF SO.. you Bought Junk Mate.
I've dissasembled motors with 75k miles on them that showed better cyls/chambers. condition. Rings are likely Shot as well as Valve Guides in my estimation.
Gawd knows What? the rest measures out as.

Add in an incompetent 'reasasembler" and you get a 10 minute ride

Junk yards are Legend for being Pure BS .. All ..their motors are Low Miles driven by an Old Lady.
Buy NO motor unless you either See it running, Have it apart for inspection or in the V least witness a comp test. Get a warranty in Writing.

Unfortunately nicely painted is just Lipstick on the pig.. Until.. it runs like New.
G'luck

 

Agreed, a spanking new motor needs the rings offset, as per all instructions.
A little off topic- - but I meant to also say that once the motor is running, the top ring spins one way, and the second ring spins the other, and in ten minutes, all rings are in various orientations relative to their perfect starting positions. 2 stroke rings are pinned to prevent rotation.

 

I can't be absolutely sure without examining the engine and measuring a few things.

It appears, from the looks of what appears to be a fracture in the Cylinder Liner at the Top of the Liner ... just below the Cylinder Head ... that you had Piston which was too small for the Bore.

You might have needed Oversized Rings or an Oversized Piston.
The Piston "Slapped" and a chunk of Ring broke-off and began doing the damage to the Crown and Combustion Chamber.

After you Honed the Block you should have Measured the Inside Diameter of the Holes.
Following a High Mileage Honing you would have needed either Oversized Rings or Oversized Pistons.

Having too large an Inside Diameter after a Honing lets the Piston Skirt "Rock" side-to-side.
You hear a soft Knock.
The Rings are stressed and crack.
A Fragment breaks loose and does the damage that appears in your photographs.

Find a Ring and place it in the damaged Cylinder.
With the Ring level ... measure the Ring Gap.
That's going to tell us part of the story.

 

I was present and helped when the piston and rings were inserted into the cylinders. I actually set the initial ring orientation myself, so I know that it was done correctly.

The motor was warmed up definitely running for a total of more than ten minutes before I took it on the fateful last ride.

 

Good idea. I will perform this test when I finally do get a chance to pull the cylinders off the pistons.

Btw, where should I position the piston ring in the cylinder in order to perform the measurement...top, midway, or the bottom?

My understanding is that cylinder sleeves are usually tapered, which would affect the measurement depending on how far down the cylinder the ring is positioned.

 

Re: Freshly assembled XJ550 motor blows up, help w/post mort

Really? This seems hard for me to believe as the old motor had 60k plus miles on it, and I inspected the two motors side by side. The original 60k plus mile motor was in visibly worse condition on virtually all the wearable surfaces, such as the HY-VO chain, bearings, pistons, gearbox, cam chain guides and tensioners, etc.

Btw, which pictures were you able to access?

 

Re: Freshly assembled XJ550 motor blows up, help w/post mort

My money is on seized, pulled liner down then ring escaped gap at the top.

Cylinders SHOULD not be tapered. They are round when new. The top will wear faster because the pressure causes the rings to bite the cylinder wall harder there.

 

You should measure the ring end gap at the top, middle and bottom of the bore in the ring travel area (this will give you an indication if the bore is worn or "ovaled"). Insert the ring in the bore, then push the piston in to "square" the ring on the bore.

The bore shouldn't be tapered through the ring travel area.

 

Good point, but a used bore WILL be tapered and the motor was built from used parts.
I guess we will see the damage soon, like tomorrow ????

 

On the topic of looking at the head, piston crown etc... any tools out there to look INSIDE without dismantling, via plug hole?

Like a camera on a stick?

I think I could make something like that...

 

Maybe if you're friendly with your local doctor you could take your bike down to him and he can perform an endoscopy..... :lol:

 

HOPEFULLY ON THE BIKE!

lol...

 

They actually make those.............

it46) Aftermarket hi-resolution viewing BOROSCOPE. These amazing devices use a miniature hi-resolution (7200 pixels) camera mounted on the end of a 1/4" diameter flexible (non-obedient) or a 3/8" diameter fixed (obedient) shaft and which allows you to probe all the dark, hidden recesses of things and then display what's "in there" on a full-color screen. Want to see what condition your cylinder walls are in, without pulling the head?: then go in with the magic wand thru the spark plug hole and get a lighted, detailed view. Condition of your primary chain guide? The deep dark recesses of your fuel tank? Just like superglue, these have a 101 uses.....probably more.

A pressure-sensitive, momentary-on, housing-mounted light switch allows you to illuminate objects with a powerful halogen lamp and explore items within 3/4" of an inch away, and within a 40-degree field of view, while an integrated focus ring allows for smooth, continuous focuing precision.

HCP10306 Aftermarket BOROSCOPE with 18" long non-obedient shaft.
$ 154.95

HCP10305 Aftermarket BOROSCOPE with 18" long obedient shaft.
$ 154.95

HCP10307 Aftermarket BOROSCOPE with 18" long non-obedient shaft and with obediant shaft attachment......giving you the best of both worlds. This unit also comes with a replacement light bulb, a mirror attachment on the end of the shaft (to provide 90-degree viewing abilities), and a magnetic tip for parts-retrieval tasks.
$ 229.95

 

Little pricy, think I'll stick with hacking my old PC camera up and a real strong light We'll see.

I knew you had em too

If you think about it, it's really not that bad a price. Just don't have the money to blow on something like that

 

Re: Freshly assembled XJ550 motor blows up, help w/post mort

It's an INVESTMENT, Doug, not an expense.

BTW, you should think of all the products that I offer in that manner.......