[Fatjock]

I'd arranged with TwoWheelers to meet up for lunch Saturday with our wives. The meeting place was about 73 miles for me, 80 for him, so a good mid-point.

When I got home Friday, I checked tire pressures, oil levels, lights, and fuel levels. I knew we were good to make it there, and fuelling up for the way back, would leave enough for a few days commute.

Saturday morning, with my wife on the 650, and me on the 400, we had a very pleasant ride down, and had a good lunch with excellent company. But all good things must come to an end, and it came time to ride home, and I had to admit I was looking forward to it as a nice way to cap things off.

We stopped to fuel shortly after leaving, and headed out.
When we got on the open road out of town, my wife behind reported my 400 seemed to be getting noisier (we have helmet intercoms).......all appeared good with the instruments, so I gave it some gas to see how things responded under load. It did seem louder under acceleration, but not excessively so (to me anyway), and responded normally. So we settled into cruise mode........

.......this lasted for about five minutes at about 64 on the speedo, 58 on the GPS, and then with pop I began losing engine revs. I gave her some throttle, and revs began climbing, a single thump, and revs went straight to zero.


At this point, I have to say that it was a bit of Deja-vu. Shortly after I bought the 400, the engine seized, and the symptoms were remarkably similar to what occured this time. Last time it cost me a piston, two intake valves, and about $700 in parts and labor to get the engine rebuilt......and having spent $70 to get the bike towed the 7 miles home, I had uprated the AAA membership to include bike towing.

I had enough momentum to coast to a safe stopping place, and after trying the key once to be rewarded with a "clunk". We called for a tow truck, that got there in about twenty five minutes. I tried to convince my wife she'd be more comfortable in the air conditioned truck, but she wasn't having it, so as the 400 was getting loaded, she headed out on the 650, and I went with the wrecker.


The biggest difference between last time on this, is now I have a garage, and so can work on her myself, instead of having to trust others (plus I know a lot more about Burgmans), so fast forward to this morning, and I got started in stripping down.

Engine covers off, seat off, both leg shields off, Underguard off, and CVT filter cover off, so I could start on the engine.

I drained the coolant, pulled the air-box, the throttle body, the valve cover, camshaft, rockers, and finally the cylinder head........

......below is a pic of what I found then.





Looks like I've got some work ahead of me!

 

[Buffalo]

Bummer, how many miles do you have on the engine since it was rebuilt?

 

[InfernoST]

Sorry to hear to about your misfortune hopefully you'll be able to get her back up and running real soon, thank god your OK. What year 400 and how many miles on her?

I only remember seeing damage like that with my 2 stroke dirt bikes.

 

[Fatjock]

She's a 2006 400s, with just under 17,000 on her at failure, with 4,500 or so since last rebuild.

To be brutally honest, she's never been right since last time.....and there was less damage then, though the piston was holed.
When we inspected the cylinder bore it was scratched, but not too badly, so it was honed. When chaecked afterwards, it was in spec for a standard cylinder, but only just. Right on the limit.

So I had to decide whether to send the cylinder out for re-bore (the mechanic doing the work didn't have facilities for this), and go with an over-size piston, or leave it as-is, and go with a standard piston.

I elected to go the cheaper route, and with hindsight, the wrong route. I don't think it helped that a coolant hose blew off on the way home, dumping the coolant on the road, and while I wouldn't say for sure she overheated, she did go way over where I would normally be comfortable with. But by this time I was so frustrated with mechanic doing the work, I was just not going to take her back.

Shortly after the rebuild, she began burning oil, and continued to do so from cold, with things sealing up when up to temp.

This was the longest run I'd ever taken her on (around 150 miles total) since then, because it's only in the last few months I've begun to trust her (done runs up to 100-120miles, but never more).

 

[Fatjock]

On the good news front.....

The cam looks in excellent condition, and it looks like only a single valve damaged, so if I go rebuild, rather than replace, It will be a Piston, cylinder, and a valve (or two). Plus of course ,the obvious gaskets, fluids, etc.


On the bad news front......

With the piston disintegrating, I may have to pull the engine and split the cases to ensure all the debris is cleared. A long way round for a top-end rebuild.....

 

[Buffalo]

You may be in the situation I was in when my 650 broke a valve then broke another 3600 miles after a rebuild. The cause for the first holed piston may not have been found and corrected leading to the second one also failing. I think I identified what cause my problem before I did the second rebuild. I fixed that and I've got about 5,000 miles on it since then with no issues.

Good luck on getting yours up and running again.

 

[knucklehead]

If that were my motor I would take a long hard look at the fuel injection for possible lean conditions, and at engine ignition timing for possible problems. One time might be a fluke but twice with the same motor tells me something isn't right.

 

[Buffalo]

Another thing to check out is the nozzle that sprays oil on the underside of the piston. That oil cools the piston and if it is not aimed correctly or if it is clogged then the piston could be getting to hot.

 

[Scootereno]

Wow sorry to hear the sad/bad news.
I wish I was back down there to help you tear it apart.

 

[Fatjock]

Wow sorry to hear the sad/bad news.
I wish I was back down there to help you tear it apart.

I can't really say it was totally unexpected, Steve......and very glad it happened when I was riding and not someone else!


I'll get her fixed, even if it takes some time. I don't know If I'll work on 'er through the week,or just on weekends, but The engine will be out by Saturday evening, then to repair, or replace?
Both have merits, and potential pitfalls, but either way, it'll be fun. :thumbup:

You know when ever you're in the area you're always welcome to pick up a wrench and join in.

 

[TwoWheelers]

Jim,
Get the baby Burgman up and running.
The wifester has some rides planned for the four of us.

 

[Mel46]

I just hope that doesn't happen to my 2006 400! I have very little experience with tearing down a Burgman so it would probably end up in the shop. So far it is running fine, except recently, my last fuel up. It started chugging while sitting still and had very poor pickup. I went to the dealer and bought some stuff to clean the injectors and it seems to be back to normal now. If it is going to go bad I hope it gives me more notice than you got. Good luck with the rebuild. By the way, if I were you I would probably go with the rebuild vs putting in a new motor because you would definitely know what is in the engine if you rebuild it. You can't say the same for an engine that your hands never touched.

 

[TwoWheelTim]

Happy to hear you and your wife are safe after that miss-adventure. That looks worse than any of my numerous 2-cycle melt downs. Some engines are just plagued, I had one that I was happy to part company with. Hope you get back on the road riding soon.

 

[Fatjock]

I just hope that doesn't happen to my 2006 400! I have very little experience with tearing down a Burgman so it would probably end up in the shop. So far it is running fine, except recently, my last fuel up. It started chugging while sitting still and had very poor pickup. I went to the dealer and bought some stuff to clean the injectors and it seems to be back to normal now. If it is going to go bad I hope it gives me more notice than you got. Good luck with the rebuild. By the way, if I were you I would probably go with the rebuild vs putting in a new motor because you would definitely know what is in the engine if you rebuild it. You can't say the same for an engine that your hands never touched.

Yeah, I think I'm pretty much going the rebuild route. Should be a little cheaper, and I find I'm really enjoying the work so far.

I wouldn't be too worried about yours. I got a very good deal on mine, and I knew she'd been ridden hard and put away wet before I go her, then when things went south first time, I was never really happy with the work done. Again, I got what I paid for!

By the time I'm done, any mechanical issues should be taken care of, and I've grown very attached to her, so it's all good. (she's taught me a lot)

Have you tried doing the Idle adjust cleaning for your rough running? It's a simple job, and offers results. I'd recommend doing it every oil change, or so.

 

[v8eyedoc]

The photo of your piston (or what is left of it!) almost looks like your valve timing was off and one of the valves hit the top of the piston right at TOP DEAD CENTER........????? Whaddaya think........????

 

[Fatjock]

I can't be certain, but that could be secondary damage after the fact.

Only one valve appears damaged in any way, and when I pulled the vavle cover off, there was a piece of debris of significant sise at the bottom end of the head. Considering the valve in question is an exhaust valve, I think it may have been damaged as it tried to close, as this piece was "passing through".

So if the engine was still running with the valve bent and stuck, then it could have impacted to cause further damage. Difficult to say, but it all need to be replaced.

Below is a pic of the head as is. I intend to replace both the exhaust valves, and clean up the head and intake valves.

 

[Fatjock]

So I have the bike with the engine ready to come out. Since it's been in there for a few years now, the mounting bolts weren't too keen on coming out, so I figured I'd get some help to to it, rather than risk dropping it off the jack.

One thing I found annoying was that I had to strip down the front end, removing the front leg shield and front box, just to have access to disconnect the crank position sensor. That's a lot of work for one electrical connection, that could easily have been placed elsewhere. A poor design

Thanks to CliffyK I pulled the wire mesh oil filter, and found a lot of debris below it. So I'm more confident about the conditions I'll find when I split the cases so we'll see what happens.

On the bad news front, when I drained the oil, only 400ml came out, and that looked way older than the 1200 miles for which I know it had been in there for. It was very dark, and very thick. The oil burning issue must have been way worse than I had thought, since the oil level was checked and adjusted the day before the trip, and I'd probably only done around 90 miles since the check......so that represents a usage rate of 1.5l per 90miles!!!!!!
So I now believe the failure was for a lack of oil, but the lack of oil was caused by it being burned off at higher rates than a stroker.
I have some investigating to do, but I suspect that the piston was never really sealing since the last rebuild (this is the first time I'd actually checked the burn rate, but always knew it was happening), so it was only ever a question of when.
I should have replaced the cylinder that time.......but hindsight is always 20-20. Besides, I didn't have the budget available then, and I got a couple of years out of it.
Final drive oil (changed at same time as engine) looked like new, and 200ml came out. So all good there.

Anyway, below is a pic of how she is now with the tupperware off and ready for the engine out. I apologize for the quality, but it was a quick snap on a cellphone camera.