Cracked oil pan

What would be the cause of an oil pan on a 550 to crack? I went to dump a quart of oil in the bike, and of course, it all ran out. My first assumption was that it puked a rod cap or something similar, but I have not found any chunks after pulling it out from underneath the bike.

And unfortunately, this is how I bought the bike because the seller wanted to offload his problem child without at least stating that.

Any ideas? The pan is cracked almost the entire width, and pushed out like (again) something tried to force its way out.

 

Pics? I think the crank may be a little too far up and forward, you would see that bulge elsewhere.

 

Here it is. It goes almost all of the way around.

No internal or external scuffing to be found.

 

This might sound crazy but the PO could've tried to jack up the bike with a car jack???? Heard it crack then sold it... That's was my first thought.

Jim

 

I doubt that's the case, as there's no scratches whatsoever on the bottom of the pan itself (and the cracks are pushed down towards the ground). The collector has absolutely zero evidence of being jacked up against at any given point in time (the bottom has a little bit of surface rust, but that's about it).

 

Wow, that's a neat one for sure. Engine still in the frame? No scuffing or anything, like he somehow hit a curb and caused that? Any stress lines inside? Just trying to figure what could have started it, and if there's any internal damage. Have you taken the timing cover off and tried spinning the crank with an open 19mm wrench?

 

Engine turns over 100% A-OK. Starter works, and it's getting 130-ish PSI per cylinder.

I'm just glad I caught this before I dumped a ton of money into it & then tried to fire it up without oil. :?


I'd love to find a replacement pan, but if it's going to be cost prohibitive, I may part out the rest of the bike to people who could appreciate it more than I can.

 

I'm as confused about it as you are. I'm wondering if there was a catastrophic failure somewhere, or if it was the PO being a retard & doing something stupid.


Not a single friggin' scuff on the pan, inside or out.

 

That's what most PO's do. But for alternative theories, I'm trying to think of what's above that punctured part of the pan. Shift drum? Too far back. Have you taken off the clutch cover to see if you can find anything on that side?

 

Weird.
Ebay lists over 20 oil pans, all of them under $20. If that is cost prohibitive, you have chosen the wrong hobby.

 

Phew, $20 I can live with. I was expecting more like $100-$200 with my luck.

Took the clutch cover off, couldn't find a friggin' thing.





Either way, I'll be pulling the engine for an autopsy. I don't know if the PO spun her too fast or what, but this is confusing the shit out of me. :?

 

I'll sell you one for over $100.00!!!

Lol, just kidding .......... Oil pans are cheap.

Looks to me like it got water in it and it froze.

 

I think freezing is likely too. You might have picked up a good deal

 

Wait you shouldn't do that (I'm totally asking seriously ). I've jacked my 750 seca up many times from the flat spot under the oil pan, while the bike was on it's center stand, so I could slide a jack stand under the front frame cross member (to get both wheels off the ground). Of course it didn't stay on the jack for long, and I did use a hockey puck to distribute the load and reach the oil pan. Guess I've just been lucky?

I don't know about freeze damage, under no circumstances should the sump be that full of water and nothing else to lower it's freeze point.

 

wow, a problem that has nothing to do with adjusting valves or setting floats

 

I doubt it was a jack. The crack spears to have come from the inside, it's not pushed in from underneath, at least the way I am viewing it. It would take that much water to do that via freezing, either.

Dave

 

Mechanical stuff I'm 100% A-OK doing. It's just when I find this kind of stuff that I freak out & try to figure out how it happened.

I'll dig into the engine a little further today. Either way, it's coming out for an autopsy.

 

Lol Polock!

I agree that it could be lots of water in the oil that froze and cracked it.

 

What's the likelihood of a "flash" explosion of all the gases inside the crankcase when they hit the optimum 17:1 ratio ??
(think spud gun)

This would leave no evidence. (just sayin)

The *POP* and oil dumping out got the PO to stop and sell the bike.

 

Can you see any indication of the oil coming out hot? Not even sure how that would look different, but . . . Or getting blown rearward, indicating it happened at speed? Both questions are trying to disprove the freezing hypothesis.

How about some other loose bolt or broken off chain guide bit getting smashed into the pan by a con-rod clamp or lobe?

Does it look like the PO had already removed the pan? Or does it seem like you are the first since Yamaha put it on? If the former, the offending bolt or bit might have already been liberated. I know you said that the pan looked clean on the inside, but a bit of chain guide might not make a mark the way a bolt most likely would, and I think I've read here that there is some chain guide that tends to break up. Primary? Can't remember.

 

Adding oil to water affect the freezing point. A crankcase full of water would mean lots of other bad things in the engine. This isn't like a frame crack, where water can collect if drain holes aren't clear, water sitting in the engine is BAD.

And ice has to expand against something to crack it. Meaning that the engine would have to be full to the brim with water.

Could you hydrolock and engine and crack the oil pan (i.e. gas from leaky floats fills the crankcase)?

 

Ice can freeze, thaw, freeze and creater a later that doesn't give. I've seen enough frozen engines with cracked blocks because of that.

It could also be something as simple as:
A guy was working on the engine, took the pan off, later dropped it and said 'I'm in trouble, I don't know what I'm doing.....' and put it back on and put the bike up for sale.


How many of us have gotten bikes that way?!!!? Could very well be you got a good snag that way.......

I have one right now that I got because it has an oil leak'. Yeah, it leaks all over the place. Why? Because the oil sensor is missing........

Dave

 

Personally, seeing as there's no marks visible inside or out & you have good compression on all 4 pots I'd be very tempted to leave the engine in the bike for now at least.

I'd pull all the plugs out, then with it on the c/stand I'd select each gear & rotate the wheel to check the gearbox is in one piece (to create a crack like that the box would either not select or be missing a ratio or 3 IMHO).

Providing all the gears selected & it turned freely/smoothly in each gear, I'd put a sump (I'm English! lol) on it, add battery, oil & petrol (again, I'm English ) and see if/what she ran like before deciding to strip it...

 

I have to agree. I wouldn't tear the engine down too far since it seems OK at this point; you're getting nice compression numbers for a 550.

A bit of possibly trivial (but possibly not) info: the USA-market 550s all had natural-finish engines. (Bottom ends, anyway.) For the oil pan to be black, it had to have been painted black, probably by the same PO.

I'm thinking he might have dropped the motor (on the cracked side) when it was out of the frame.

 

I'm very confident the pan was never off of the bike. The screws were all super, super tight in there, and never appeared to have been touched afterwards. On top of that, the pan itself was a bear to pop off of the bottom of the block.

Otherwise, I figure 130psi with need of valve adjustment is probably pretty good (I need shims, and badly). That's with the cylinders dry.

 

OK here's a weird thought that just occurred to me (and I mean weird, but you never know with p/o's...)

What if it had been laid up for a long time & the p/o decided to check the engine out as you have done, and got himself a leakdown tester. Now consider the guy has the tester, compressor & maybe a lathe too, but NO clue what he's doing when it comes to bikes... Just maybe he somehow decided that the tester screws into the oil filler & so he inflated the motor until it popped?

Highly unlikely I'd think, but just throwing it out there since you never can tell what's gone before (I recall a previous member who drilled their crankshaft for lightness, so it's definitely possible...)

 

This made me laugh because I had just read that thread again earlier today for nothing more than pure amusement!

Here it is if anyone's interested!

 

i had this years ago (30) on a honda it turned out to be to much petrol (gas) in sump (oil pan) flash point much lower, due to a leaking float valve, at the time it was hard to find because float valve was only weeping over night not poring out.

just one to look for

 

Must have been quite an explosion, denbola.

 

it was a honda c90 was not a big bang just a chuff noise and white smoke from around caseing and a line of oil road, split centre caseing, second hand engine

 

I didn't suggest the pan was OFF before; I said it wasn't black to begin with which meant it was painted (along with, I assume, the rest of the motor.)

In order to paint the underside of the motor, it was probably out of the frame.

I'm thinking it got dropped on the cracked side, and inward pressure on the side of the pan caused it to pop like that.

 

Fitz, I'm going to take it that you're right (and I can see this happening). I can also see the ice issue as well, as the PO left the bike out over winter with the valve cover OFF (of which, I have verified that no other damage has occurred, thankfully).

A few beers later & with the use of a mirror, I have determined that there is zero damage to the rest of the engine. Other than a bit of carbon, there's no other damage.

XJ project will continue on. I really wanna get this thing running (having a feeling I'm going to need a new left-hand side coil, as it does not fire) so I can tackle the brakes, install a new front tire, chain, sprockets, & get going. :wink:

 

Ok, I take back what I said, if the valve cover was off, outside, then freeze damage is definitely likely.

I have no experience rebuilding engines, but are these things really salvageable when they've been filled with water? That doesn't oxidize steel components in the engine? Like bearings and races that will wear in a hurry once you put it into service?

 

Everything is still nice, slick, & shiny inside (as in, there's still a LOT of oil, and absolutely zero signs of corrosion). Cylinder walls are absolutely perfect.

 

OK - - Suzuki outboard, 115 HP, mid '90's

Something got loose and in the crankcase at WOT and knocked a clean, little hole in the "bottom" , which is forward.

Fixed with JB-Weld without any further work.

I'm having a hard time seeing a guy drop and crack a motor, then proceed to re-install everything.

Must've had an Electric Monk ! :wink:

 

Thanks for the link, couldn't find it earlier... Wonder if he's paid off the dyno damages yet?