Lost Compression

vanbry · Post by **vanbry** » Fri May 30, 2008 8:05 am

Morning All,
I got my kids '86 spree running pretty good over the past two weeks, with the help of this forum.
Last night he went out for a ride, and it quit on him. When he got home with it and told me that it had quit, I went out an looked at it, and without an official compression test, I can tell that it has little to no compression by kicking it over. I pulled the plug, and it's a nice chocolate brown, but my guess is that the rings are melted to the piston, as I read about in another post.

I'm gonna pull the top end apart tonight when I get home from work, but what I'm wondering is, if it wasn't running too lean, why would it get hot enough to lose compression and quit running?

I'm in Comstock Park, MI. Do you western MI guys go to a local dealer to get your parts, or do you order online?

Thanx,

Keith

Dac · Post by **Dac** » Fri May 30, 2008 8:28 am

what could of happen was the clip came out of the side of the piston.
Its kinda rare to happen, but when it does it trashes the cylinder /piston /rings almost instanlly.
You will go from great compression to next to nothing in seconds. Happened on my 92 elite.
Or, another thing that could of happen is if a ring breaks, the spot were it broke will rub on the cylinder, killing compression real fast.

I hate to even say this, but more the likely, you are going to need a hole new top end.

vanbry · Post by **vanbry** » Fri May 30, 2008 12:39 pm

Dac wrote: I hate to even say this, but more the likely, you are going to need a hole new top end.

Gee, aren't you a bundle of sunshine

Thanx for the info Dac. I'll know a lot more this evening, when I tear into it.

Dac · Post by **Dac** » Fri May 30, 2008 2:14 pm

i hate posting stuff like that. I know how depressing it is when you think your bike has a small problem just to read something like that.

vanbry · Post by **vanbry** » Fri May 30, 2008 3:54 pm

Okay, well I got it apart; here's the piston...

Dac · Post by **Dac** » Fri May 30, 2008 4:07 pm

is that even possible?!?!?!?!?
for a second i was thinking it was just heat seized, but dude, thats crazy!

Lets jump into fixing it, Was the clip still there? Do you have any idea what was in the cylinder that might have done that?
Does your bike have an air filter on it? It almost looks like allot of dirt got in there.

dukemartini · Post by **dukemartini** » Fri May 30, 2008 4:23 pm

CharlotteSpreeRider · Post by **CharlotteSpreeRider** » Fri May 30, 2008 4:25 pm

To me, it looks as if your piston has a slight problem. There are a few scratches in there. I bet the cylinder doesn't look too much better, either. Looks like the clip came out and got torn to bits against the cylinder wall. That's gonna be a fun repair. Make sure you get all the bits out of the bottom end, otherwise you're gonna need a bottom end rebuild with new bearings.

Sorry man, that sucks *.

-aseigler

vanbry · Post by **vanbry** » Fri May 30, 2008 4:36 pm

Yup, it's pretty messed up. I don't have a clue what may have happened. The ped sat for perhaps 15 years before I got it. It has an air cleaner with the foam element, and I cleaned and reoiled it. It's entirely possible that crud was somewhere, but I cleaned everything up pretty good before running it.
The clip was still in place. The galling was the exhaust side of the piston fwiw. I just went out and looked, and there are no extra holes in the airbox either. I'm open to any ideas on what may have caused this.

Any Honda shops in the GR area stock pistons and rings?

CharlotteSpreeRider · Post by **CharlotteSpreeRider** » Fri May 30, 2008 4:42 pm

You're gonna need a cylinder too, more than likely. If it was on the exhaust side, some carbon build up probably broke loose and the piston ground it into bits. Take a look at the inside of the cylinder at the exhaust port. The hole is supposed to be about the size of a quarter but a wider. Carbon tends to build up in there and seal off the exhaust port, becoming part of the cylinder wall. But if it sits for a long time, and the temperature fluctuates suddenly, the new "wall" of carbon can become brittle and break loose inward towards the piston, creating the mess that you have there.

-aseigler

stangman · Post by **stangman** » Fri May 30, 2008 4:47 pm

It is heat seized rebuild motor. Check the cooling fan shroud and cylinder plastic cover for any damaged or missing parts. It also could have happened from a no oil / bad oil pump clogged filter or hoses. Kinda unlikely from the look of the piston but should be checked. Check your muffler if it is clogged it will overheat the motor with the same results. If the cylinder head is on wrong it will overheat. The spree cylinder head will go on two ways the right way and the wrong way. Make sure the angle on the head goes to the front twards exaust and to the right side of the motor by the cooling fan. good luck on the rebuild

Dac · Post by **Dac** » Fri May 30, 2008 4:52 pm

stangman wrote:It is heat seized rebuild motor. Check the cooling fan shroud and cylinder plastic cover for any damaged or missing parts. It also could have happened from a no oil / bad oil pump clogged filter or hoses. Kinda unlikely from the look of the piston but should be checked. Check your muffler if it is clogged it will overheat the motor with the same results.

thats what i was thinking at first, but its allot more then that. Seizes just have minor stuff. that really is shoot. There was something in between the cylinder and piston. It was just just a seize.

vanbry · Post by **vanbry** » Fri May 30, 2008 5:00 pm

Kinda hard to tell in pics, but I think that the cylinder will be okay. I obiously will have to hone it up good. This thing may have been on the verge of going before I got it. We've only had it running since Monday. I'll check the exhaust. All of the plastic around the cylinder was intact(if that's what the cooling shroud is). I haven't checked the oil pump either. Now would be the time to drain and start from scratch, since I don't have a clue what oil is in it, or how long it's been in there.

stangman · Post by **stangman** » Fri May 30, 2008 5:01 pm

The piston looks so bad because it started melting and little pices of the piston fell and ate it all up

Kenny_McCormic · Post by **Kenny_McCormic** » Fri May 30, 2008 5:14 pm

Leaky exhaust sucks air in port and messes it up??? Seems unlikely in my mind because my dad has a chainsaw thats been running without a muffler for years and shows no extra wear( VERY fun to watch everything going on through the port), but people have told me it can happen.