24 replies to this topic

[gsled04]

Ok, last ride of the season today for me. Now I have a project. I got about 5 miles away from the truck and suddenly the motor locks up. The sled is a 05 600 sdi gade with 2300 miles, after I stoped I started checking things out, I can rotate the crank 180 in each direction to a dead stop. No grinding, no funny noises, just dead stop. Plugs look good, I was only going about 40 when this happend.

So before I doo a leak down test and start tearing it down I thought it would be fun to let you guy's take your best guess as to what happend.

[aklawok]

sucked reed(FOD) or broken ring/melted piston
pull y-pipe and look.

[gsled04]

Dont want to pull the y-pipe before I doo a leak down test. I just want to see who has the best crystal ball.

[snolan]

Broken piston skirt.

[gsled04]

Say it aint so !

[snowfreak56]

Well now it sounds to me like there is something on top of the piston that is comeing up and hiting the head and stoping it from rotateing any farther,,but of course at this particular time my brain is only about half engaged.Good luck.

[gsled04]

Good idea, but I already probed the cylinder's and they are clear.

[TwoRevs]

If it rotates 180...pull the plugs and do a "thumb" compression test. It might tell you if or which cyl is bad.

[gsled04]

Never thought about doing that, great idea. I'll do that when I get off work, and let you know what I find.

[golfman]

With the plugs looking good I would say its a crank bearing.

[TwoRevs]

With the plugs looking good I would say its a crank bearing.

Too bad to need a short block with only 2300 miles

[x timewarfare x]

It very well could be a bad cylinder. But I have also had a few friends with a similar type of sled, thought they had something of this magnitude happen to them too. As their sleds came to a full stop. Luckly for them, it was only their brake disc. It showed and pointed all of the signs to their pistons/crank commonalities (sled stoppage, pull cord wouldn't budge), but again, was just the brake disc. So you might want to check that out as well.

[DOO_TINT]

1 of the lower rod bearings could be really badly worn/loose and the rod is contacting the case and preventing the crank from spinning all the way around is my guess or maybe main crank bearings or magneto/stator broke,,which any could stop the crank from turning and not show a bad plug from melted piston/cyl issues

i wouldnt worry about a pressure test till you put it back together,,take y-pipe off and the intakes/reedblocks for inspection/you will find metal chips if bearings are bad and be able to see the play from bad rod bearing when rotating crank with the primary

the disc brake is on the jackshaft and wont prevent the eng from turning/chaincase also

[gsled04]

If it rotates 180...pull the plugs and do a "thumb" compression test. It might tell you if or which cyl is bad.

OK, no compression in mag side cylinder.

[TwoRevs]

OK, no compression in mag side cylinder.

Now I would do the leaktest before taking it apart. Then you will know if the seals on the crank are good before doing a top end.
my .02