Just picked up a '86 Spree....barn find

dgsoles · Post by **dgsoles** » Tue Oct 07, 2008 12:30 pm

Hi everyone, I'm new here, and I thought that I'd tell you about the Spree I just picked up. It's an '86, in really good shape (almost no rust on it!). The only things that it is missing is the petcock plastic cover and the rear luggage rack (and rear turn signals). Oh, and it doesn't run. I cleaned the carbs good, air-cleaner is very nice (and oiled, but not too much), petcock is new (it's the vacuum type), reed valve is in good shape, muffler has flow. Pretty much everything on it is immaculate. Oh, but it is very dusty. Anyway, I traced the problem to low compression. I first used the "thumb in the spark plug hole" method, and, after reading what you guys had posted here, I thought that it would blow my thumb right out of there. Nope. Pushed and sucked it, but didn't come close to blowing it out. I tested it, and it is only pushing 45 psi. Here is where I would like some suggestions/help: I took the head off, and the gasket seems to look ok (I'm going to get a new one, anyway, it's 3 bucks and the local bike shop has virtually every engine part for an '86 Spree in stock, on their shelves), so, I'm going to pull the cylinder off next and check the piston rings.

So, how do I tell if the rings are worn? It'll be obvious if they're cracked, and any scores in the cylinder will be obvious, I'm sure, but I've never actually inspected piston rings before. Also, how will I be able to tell if the cylinder has "glassed" over? Does it actually look like glass? Ok, that's about it, sorry for the long post.

Post by **noiseguy** » Tue Oct 07, 2008 12:40 pm

When you're running the compression test, is the electrical starter turning quickly enough to start, and are you holding the throttle open?

Before you pull the jug, reinstall the head and run the test after adding some oil (tablespoon) into the spark plug hole. If compression bumps up the rings are worn.

Scratching on the cylinder walls will show you wear; if the walls are badly scratched you'll need to rebore and get the next larger piston. You can do this now that the head is off.

dgsoles · Post by **dgsoles** » Tue Oct 07, 2008 1:27 pm

The starter seems to be turning fine (I haven't measured it, but it sounds normal).
As for the compression test, I actually did it with the carb off the intake....I imagine this would emulate WOT?

Now, I did an idiot mistake and already "broke" the jug loose from the crankcase....I'm guessing I need a new gasket before I put it back on to check the compression again?

Bear45-70 · Post by **Bear45-70** » Tue Oct 07, 2008 1:33 pm

Without an actually compression gauge, you have no idea what the actual numbers are. The oil thing is something any experienced mechanic knows and it works. Slow starter speed and a no Wide Open Throttle can kill compression numbers.

dgsoles · Post by **dgsoles** » Tue Oct 07, 2008 1:36 pm

I was using a comp gauge, it showed 45 psi (I did this without the carb installed, so I'm guessing it's accurate). Also, the starter sounds quite nice, not sluggish or anything.

Bear45-70 · Post by **Bear45-70** » Tue Oct 07, 2008 1:39 pm

dgsoles wrote:I was using a comp gauge, it showed 45 psi (I did this without the carb installed, so I'm guessing it's accurate). Also, the starter sounds quite nice, not sluggish or anything.

Oil it.

dgsoles · Post by **dgsoles** » Tue Oct 07, 2008 7:41 pm

Ok, just came home and tried the oil test. Compression shot up to 75 psi (from 45). I even hooked the plug back up, and she fired right up.

Of course, it didn't last. So, I have bad rings....I took the cylinder off, and now I have another problem. I broke one of the clips holding the piston on, so I can't slide that little tube out....is there a technique for taking these clips out? I'll try to take the one on the other side out as soon as I'm confident about it. Until then, I'll just clean the cylinder, exhaust port, and head. Can't hurt.

Post by **noiseguy** » Tue Oct 07, 2008 8:59 pm

Hmm. You didn't need to remove the piston unless you re-bored the cylinder. Now you'll need to remove the piston to get the other clip out. Make sure to use new circlips for this.

dgsoles · Post by **dgsoles** » Tue Oct 07, 2008 9:09 pm

Yeah, sorry, the piston has a huge amount of carbon build-up on it, and I wanted to take it out to clean it. So, is there a technique for taking the clips out? Do I spin them out? I've never done this part before. Thanks

Kenny_McCormic · Post by **Kenny_McCormic** » Tue Oct 07, 2008 9:17 pm

The easiest way to clean the piston starts with a running assembled motor.

dgsoles · Post by **dgsoles** » Tue Oct 07, 2008 10:10 pm

Ok. Since I already broke one of the piston pin clips trying to take it out (which I realize was stupid now), I need to be able to take the one on the other side out so I can remove the remnants of the broken one. So, how does one remove the piston pin clips? I'll get new ones at my honda dealership (here is Lansing, I have one 3 miles from where I work....they have almost every engine part in stock! I don't even have to wait for shipping.).

Post by **noiseguy** » Wed Oct 08, 2008 9:27 am

Read the service manual in tech docs for the procedure. You should be able to remove the remaining clip and pull the pin. Watch the pin bearings on the top end of the rod so they don't fall into the engine; put a rag into the case so nothing can fall in.