Monday both my Pilot engines suffered bearing failures, on mine the rod
squeaked tight, after towing my Pilot back to the parking lot (thanks
Pilotman!!!) I got out my wifes Pilot only to have its clutch side
crank bearing lock up in about the same time (10-15 min) of ride time, but why?

In my life I have seen my fair share of failed parts I have seen countless ATV
engines apart, I have seen rods that were so worn that you can feel the gap
in the worn bearings, the rod made a metallic sound when you raised the rod
up and down, I have seen crank bearings so worn that you could move the
flywheel up and down and feel play, Odyssey engines so bad you could feel
bearing play by moving the clutch up and down by hand, they never turned blue
and locked up tight so it is safe to say that when they lock up tight and turn blue
it must be from a momentary lapse of lubrication? What would cause this brief
lapse of lubrication? I found a good, what I consider to be a normal amount of oil
inside my engines when I took them apart, quantity was present so I can ASSume
that quality was the problem? Both the crank bearings in the wifes Pilot and the
rod bearing in my Pilot were original bearings, they were not worn fact is when I
replaced my crank bearings the last time I had a bunch of guys inspect the rod, there
was no wear indicated by using all the normal methods of checking a rod, the crank
bearings had no play, the first time I tore down the wifes top end it was apparent that
the Engine had never been apart, the piston was on the stock bore and was not even
half worn out going by Hondas wear specs, the Engine was a very low hour Engine,
both engines top ends were ok, the pistons, rings, bearings didnt show any scuffing
and wear they had enough lube.

I guess my next step is to contact Amsoil then send the oil out to be tested to see
what is the deal?I have new unmixed oil, I have unmixed gas I used, I have the gas
that was mixed still left in the can I mixed them in, I still have the mixed gas/oil in
each Pilot gas tank.

Any ideas?

sled motor (( Internal Combustion Engine ? ))

Drag....times 2!

what kind of gas ? i'm just wondering if ethanol would affect the oil. sounds like a pretty big coincidence or the oil/fuel like you said .

Amoco 93 octane from same station I been buying from for past 8 years..

in my experience a lack of oil usually shows up in the top end quicker . a venting problem would be my next guess , either blown seal[s] or crank case vent but it's way to big of a coincidence for both machines. overheated ?

Top ends are like new and not damaged, it was not a air leak or over heating.

water in the gas ? what did they run like prior to kaboom ? any white smoke , stutter, coughing ect. ? i'm not sure but if an Engine is hot a little bit of water although not good for it will just vaporize and flush out the exhaust but if its cold any water can be devastating to an Engine.

No water, both ran perfect right up to the last second!

Some pictures http://pilotodyssey.com/coppermine/index.php?cat=7

You, sir, have your hands full! What are you going to do, fix one Engine, then drop a different powerplant in the other Pilot?

Yeah right now it looks like I am going to install one sled Engine into my Pilot then rebuild
wifes and put hers back into her Pilot, if mine works out then will keep an eye out for
another sled Engine for hers.. mine will be all bolted in so I cna simply unbolt and
go back to the Pilot Engine at any time if I wanted to.

No frame stretch? How tight is it? Custom expansion chamber? So you've given up on finding a proper 4 stroke that would fit? That's a lot of question marks, isnt it? Damn, another one! Finally!

Not going to stretch the frame I see no reason to, I havent found a 4 stroke sled Engine
yet I suppose in the years to come the supply will get better, I will use the 2 stroke until
I can find a complete wrecked 4 stroke sled then maybe buy one and make the swap,
pipe will be billy-bob custom pipe until I get the bugs all worked out then I will look into a
tuned pipe.

that's just bad luck you don't deserve
monkey wrench

Nobody does I would not wish that kinda luck on anybody...

UPDATE:

I know its been a while but I will update anyways, the Engine out of my Pilot has been setting on the bench since the POOFKABOOM, I had performed the 440 sled Engine swap so I just let it set and collect dust on the bench, the wifes Engine was rebuilt and reinstalled and is running today...

I split the cases, the rod bearing is bad, it did not go so bad it trenched the cases just enough to lock up.

For those of you keeping track of the Pilot crank bearing saga please note the crank bearings are LIKE NEW, no play, no ghosting on the balls or races, no discolorations heat trails etc. they will NOT be reused NEW bearings, seals, gaskets, crankshaft, piston, rings, wrist pin, wrist pin bearing, C clips are on order and will be here any day...

The crankshaft itself is in GREAT shape, NO grooves worn where the crank seal rides, NO HAMMER MARKS where it looks like it was BEAT TOGETHER, NO galling where the bearings were, no signs the inner race of the bearing has spun on the crankshaft.

Once I get the parts cleaned up I will take more detail pics and post.

If you look close you can see the cage that separates the bearings is worn flat, it is actually locked on, fused to the crank pin the rod just spins around the bearing.

Cases soaking as type this in mineral spirits to soften the gaskets for easy removal ...

Stay tuned I will have more as I rebuild this whole Engine...

Brings back horrible memories of last summer for me.

New parts

New rod assembly for the crank I just removed.

I fired up the grinder and made a mark on the pin and the crank so when I get it back I can match up the pin with the crank and look for wear patterns on the pin and rod, the H means its hoser's crank heh

New bearings installed in the cases.

Factory white paint mark indicating what crank pin it has their is also a "G" stamped into the crank lobe.