Still can't get my new 1986 Spree running

[vintagegarage]

I've been working on my new 1986 Spree for about a week now and am getting pretty frustrated. I've checked all of the easy things, and now the tests are getting more and more destructive as I get deeper and deeper into the engine. The previous owner of it had also given up on it. He says it was running fine and just stopped while he was riding down the highway and he had to walk it home. Not sure that is true, but I don't have any reason to doubt it. It looks to me that most of his debugging was related to the carburetor, but I am not sure.

The compression seems pretty good.. about 118 PSI cold. I have swapped the coil and CDI unit with two other known working ones. Same for the carburetor.. have tried three. The spark looks hot and normal to me when I watch the spark plug tip. When I first got my Gyro and Aero 50, they didn't run either, and if I put a few drops of gasoline in the spark plug hole, put the plug in, and hit the starter, they both would run for a second or two before running out of gasoline. When I do that on the new Spree, I get a few pops, and some of the pops are slight backfires through the carb. All of the external electrical tests look normal. I removed the intake pipe, and the reeds look perfect. It is clear to me that I was the first to remove the intake pipe. When I spin the engine on the starter with the sparkplug out, the engine turns fast enough to make the headlight glow a bit. I took off the muffler to see if it is plugged, and it is not.. air flows freely through it. The Spree has less than 1,000 miles showing on the odometer, and I think it is correct, based on how much of the engine had never been apart. When the muffler was off, I looked through the exhaust port with a mirror, and thought that perhaps the bottom piston ring was broken. So I took off the head and cylinder, and found that they had never been off the engine before. Much to my disappointment, I found that the piston rings and piston were in nearly perfect shape, and looked like a less than 1,000 mile engine. All I accomplished by inspecting the piston was to destroy the perfect factory seal between the head and cylinder, and between the cylinder and the case. I cleaned the surfaces as best as I could and installed a new head and cylinder gasket. Compression before and after the piston inspection was still at about 118. PSI cold. The pulse generator has the correct resistance, and like I said earlier, the spark at the plug is strong and regular.

Now I am back to thinking that either something is wrong with the reeds, or else something is wrong with the ignition timing. So here are my questions for the forum:

Reeds:
1. With the intake pipe off, I watch the reeds while spinning the engine on the starter, and they barely open. Is this normal?
2. The service manual indicate that low compression might be caused by bad reeds. However, if I gently hold a reed open with a small wooden dowel, I still have pretty good compression, and don't see much of a difference. Is this normal?

Timing:
3. Has anyone done a static timing test on a Spree? I can see the raised flat bar on the opposite side of the flywheel from the "F" mark on the flywheel. I assume this bar triggers the pulse generator when it passes across the pulse generator. Has anyone compared top dead center of the piston to the location of the "F" on the flywheel? If so, where is the "F" when the piston is at top dead center? I have a flywheel puller coming in tomorrow, and even though it seems impossible to me that the flywheel has turned on the crankshaft causing the timing to be off, I plan to pull the flywheel tomorrow to see if the crankshaft key is still in it. It is clear to me that the flywheel has never been off of the engine, and is still as installed by the factory, so I don't expect to find anything wrong.
4. Has anyone found a pulse generator that was bad enough to make for incorrect timing, but good enough to make a hot spark?

I'm pretty discouraged too.. not ready to take the Spree to the dumpster and to get another one, but close to it.. any help or other ideas would be appreciated.

[Wheelman-111]

Greetings:

I once installed the magnet flywheel incorrectly and the Aero gradually began running poorer and poorer until one day it wouldn't fire at all. You'd think ham-fisted reassembly would be the ONLY way for this to happen, but I guess it's possible Factory Guy Izumi stayed out too late drinking Sake the day yours was bolted on...

Did you change the spark plug, just on principle?

Cylinder and head sealing have to be Perfect. Reed block too. On a Spree, the entire intake tract including the air box and filter must be tight or it'll be hard to fire. Old seals at both crank ends could have gone brittle and leaked. Flywheel pull will tell. Reeds only open under negative pressure a hair. As long as they admit a puff of fuel, it should sputter at least. Did the crankcase smell of gasoline? A leaky, non-closing reed should affect compression at least a few points. Look for other places (seals?) where compression is being lost.

It's just gotta be something. You'll find it.

[vintagegarage]

Thanks wheelman... not sure I will work on it again until Wednesday.. then I'll probably spend all day on it. I have been changing sparkplugs and putting a brand new one on at the start of each debugging day.

I really expect that the flywheel has not turned on the crankshaft. Even if the factory worker put the flywheel on without the key, if the nut was torqued to spec, I would think the shaft taper would be enough to keep the flywheel in place. As I understand it, the engine ran perfectly for the first 800 miles or so.

I didn't include the possibility in my thinking that the crank seals were bad, but now that you mention it, that is a good reason to take the flywheel off anyway, so I will do that. There is a slight breeze coming out of the left side cover breather, so I guess there must be some slight leakage on that side.

Also, I haven't tested it with the complete air tract in place except for the first day I worked on it. I will put the airbox, filter, and elbow back in place. I had it off because it was easy to squirt gasoline into the carb venture, but it isn't that hard to just put a few drops of gasoline into the spark plug hole. I supposed that eventually, I will strip the sparkplug threads in the head taking the plug out and in so often. The more I work on the Spree, the more damage I am doing to it.

It does sound like my reeds are working as they should.. they look perfect, and as I said, I was the first person outside of the factory to look at them.. the seal between the reeds and the block is still factory and tight. The seal between the reeds and the intake pipe is as good as I can make it and I don't think there is a leak there.

Also, the more I think about it, the pop I hear might not be blowback through the carb. It might be blowback into one of the side cases. I will study that some more too.

[patthesoundguy]

Wheelman is right about trying a new plug. Ive had a couple NGK's fire outside the motor but not once re installed. Had me cursing for hours! I have also had the battery low enough that it would crank fine or what seemed to be fine but would not start. charged the battery or jumped it and it fired up the first push of the button. I have also had both of those problems happen at the same time
I have also had my spree start and run with half a reed petal missing. as long ast the reeds close and are not too chewed up you should be fine.

[vintagegarage]

Patthesoundguy.. I hear you. Your info about the reeds is much appreciated. I am pretty sure based on your info and more testing that my reeds aren't the problem. I am pretty sure I have a hot battery, and also I get the same pop back through the carb when I use the kick starter. I've been through about 6 new NGK plugs.. one a day for about a week, with no success. I still think the ignition timing is off somehow, but I'll know more when I take the flywheel off later this afternoon or tomorrow and do some more testing. I'm also looking to buy a parts spree or a running one so I can do some comparison testing.

[vintagegarage]

The flywheel puller came in today and just as you would expect, there is nothing wrong with the flywheel key and the crank seal looks fine, so I am about at the end of my rope. I've pretty much replaced or tested everything on the Spree, and it all checks out fine, yet it still sounds like the timing is off. About all I can get is a pop through the carb about every two or three revolutions and that is only when I preload the cylinder with a tiny bit of gasoline. On the gyro and Aero 50, if I put the same tiny bit of gasoline in the cylinder, the engine will run for a second, even when there is no gasoline in the carburetor. I haven't swapped out the pulse generator, as I don't have a spare. The pulse generator tests ok at 122 ohms and works well enough to tell the CDI box to fire once per revolution of the flywheel.

By the way, I assume that the section on page 14-10 of the Spree workshop manual has an error and a couple of extraneous boxes. Under the heading Pulse Generator Inspection, there is this note: It not necessary to remove the stator to make this test. While that is true, that comment is repeated in the next section and it belongs there. The next line says to disconnect the stator coupler, and I assume it should say to disconnect the pulse generator blue/yellow wire connector. The pulse generator connector is located near the stator connector. Lastly, the caution to replace the Stator and Flywheel as a set doesn't belong in this section and is repeated below, where it is meant to be. It looks like the author of the manual used copy and paste carelessly and didn't proof read the section. Let me know if I am wrong.

I am stumped now, and pretty much have to give up and buy a second Spree so I can put them side by side and make comparisons of everything. Time for a nap..

[motormike]

I am lurking in this thread.
I have had a similar affair with a Spree recently.>> viewtopic.php?f=3&t=31281&hilit=flow+Spree+petcock
Never did get it sorted.
Wishing you some luck and success soon...

[vintagegarage]

Motormike,
re: fuel valve.. My thinking is that if you suck on the Spree petcock hose and get the carb bowl full of fuel, the engine should run for about half a city block on just the fuel in the bowl, even with a stuck petcock.. my gyro does when I forget to turn on the fuel petcock. I am going to build a rubber ring to reduce the venturi size on my uni-syn that I use to measure air flow in automotive carbs, so that i can compare air flow on the starter for the aero 50 vs. the Spree. Maybe even though I have very good compression measured at the spark plug hole, maybe something is causing lack of air flow through the carb. I still think though that with no fuel in the carb, the engine should run for one second on just a teaspoon of gas put in the sparkplug hole.

I keep going back to what the prevous owner said.. the engine just stopped while he was riding it, and it ran great right up the second it quit, and he was several miles from home. I still think something broke.. I just can't figure out what, but I don't think it is related to the carb or fuel system.

I am going to buy another Spree so I can do some parallel testing... at this point, I think that is my only hope. I wonder how the Golden Gyro is making out.. we might all be similar..

[motormike]

I keep going back to what the previous owner said.. the engine just stopped while he was riding it, and it ran great right up the second it quit,...I still think something broke.. I just can't figure out what, but I don't think it is related to the carb or fuel system.

The above statement jogged my memory back to the day that my '85 Aero 50 did exactly the same thing.
Wouldn't hit a lick...No amount of carburetor work had any affect.
I resolved to pull the cylinder (without checking compression) and found the piston ring to be...
... broken....1 break...2 pieces, still resting in the groove. no damage to wall or piston.
The only thing I did was put on a new ring. I think I spent $8.
The bike has been good for several years now.

[vintagegarage]

I decided to work on the Spree again today. I got to thinking about it, and since I already had taken the cylinder off last week to inspect the rings and messed up the factory gaskets in the process, I decided I might as well take it apart and put in new rings... it will never be easier than it would be today, as all of the shrouding was off, and the scooter is still on the stand. I actually broke the lower ring trying to remove it from the piston.. it was stuck on one side. I cleaned the groves and put in new rings and a new base gasket and a new headgasket. Compresson after the ring job was still about the same as before.. about 115 PSI... The engine still wouldn't fire except for the occasional pop back through the carb just like before although I may have heard it fire twice in two revolutions through the muffler, not sure about that.

The next suggestion in the workshop manual is to check the crankcase for leaks, so I started looking for possible places where there could be a leak. It occurred to me that maybe the hose from the intake pipe to the fuel valve might be leaking, or the fuel valve might have an air leak. While testing the fuel valve, I found that the engine doesn't create enough vacuum when turning over on the starter motor to open the fuel valve. So I put a vacuum gauge on the intake pipe and the engine doesn't create enough vacuum to even move the gauge off it's stop. When I suck on the vacuum line to the fuel valve, it doesn't take much vacuum to get a full fuel flow... so now I think I must have a bad leak somewhere in the lower end of the engine. Are the crank seals just simple oil seals as they appear, or something more robust?

I am sure there is no leak at the input pipe gasket, nor at the gasket between the reeds and the block. I don't think there is a leak where the oil pump passes through the block, but I am not sure. Has anyone seen an oil pump o-ring go bad? Anyone have any ideas? How much vacuum pressure is normal when measured at the fitting on the intake pipe and the motor is turning over on the starter with the spark plug installed?

[MrJumps]

this may sound totally dumb but my spree is wired by someone who likes to make everything hard in life and they rewired my kill switch to where if its off its on, and my blinkers too. Just a thought check wires and fuse.

[vintagegarage]

Another day with pitiful results. I did mount new tires on my newly painted wheels to give me some positive results. One thing nice about mounting spree tires is that you can do it easily with no tools and just hand pressure if you get the rims and tire edges nice and soapy. If you have to use a screwdriver or tire iron to mount or dismount Spree tires you are doing it wrong. Honda still sells made in Japan tires for the Spree.. 42711-GK8-673 and they should cost you about $12 each from your Honda Powersports dealer. I think I will buy a few more sets this week, before they run out of them.

As far as getting the Spree engine running, I spent a couple of hours this morning, with no success. I got tired of constantly recharging the battery in the Spree, so now I am jumpering the Spree battery from the battery of a car that is in the shop. Next thing to happen, I suppose, is that I will burn out the perfectly good Spree starter motor.

Everything is tight and factory new from air filter to the input side of the reed valve. I also put on a new exhaust pipe gasket. The vacuum draw at the fuel valve line fitting at the input pipe is pitiful. If I suck lightly on the vacuum line to the fuel valve, I get a very robust flow of fuel out of the valve. If I hook the fuel valve line to the intake pipe, and spin the motor fast on the starter, I can get a few drops to come out of the fuel line from the valve. The vacuum pressure at the valve line is immeasurable with my gauge.. pressure is so low, it doesn't even bounce the needle. My spirits are low now as every time I dig deeper, everything checks out. With everything tight, I am not getting a pop back through the carb, rather I am getting what sounds like normal firing sound about once every other revolution of the motor.. and that is until it runs out of the gasoline I put down the spark plug hole. I start every test by sucking on the fuel valve line, and I am sure the carb bowl is full and at the right level.

I am about ready to split the case to have a look inside the engine. I can't believe vacuum pressure in the bottom end should be so low while turning the engine over on the starter. Before I do that though, I need to get a running Spree so I can do some comparison testing. Hope to buy one this coming week.

[Johnniespeed]

While I have not actually done it, there is a way to pressurized the engine to check for leaks, the dirt bike guys do this. They bolt a plate with gasket where the carb goes, they bolt a plate with gasket where the pipe goes, then they pressurize the crankcase and watch the pressure gauge for loss. Apparently then you can spray soapy water over the engine and find case leaks, porous castings, leaky crank seals, etc.


I have revived more than a dozen Spree barn finds/ basket cases and everyone started except ONE , I had that engine on a stand, spent probably five or six hours in the course of two weeks, finally gave up, grabbed a different engine and finished that scooter project (sold it too) , never did figure it out, it had compression, spark, fuel. Out of frustration tried known good pulser trigger coils, flywheels, CDIs, Stators, Carbs, piston/cylinders, both side crank seals, case half gasket, the stupid thing just wanted to mess with me.

It should have run, I gave that engine away for free.

No regrets, I know where to get more Spree engines, for as little as a good used engine costs, I couldn't justify spending anymore time on it, at some point you just have to find a faster solution to get the job done.

Yeah it did hurt my pride to admit I failed at getting it running, but the goal was to sell the scooter for a quick buck, not to show off my abilities.

[vintagegarage]

Johnniespeed..
I hear you, and you may have just saved me the work of changing out the crankshaft seals.. In my case, scooters are a new hobby and I'm not trying to make money at it. I'm old and retired, and my time is worth less than it used to be. For me, working on scooters is better than working crossword puzzles. I'd just as soon try to solve the puzzle. But you are also right. It is time to find another engine. Once I do, maybe I can figure out what is wrong with this one.

I do wish that one of the guys on this list who talk about their super builds would take the time to measure what the intake vacuum is when measured at the tube coming out of the intake pipe on a stock Spree turning over on the starter. That would be most helpful to me. I'll know the answer as soon as I buy another Spree next week or so.

[Johnniespeed]

There are four guys in a large town near me who part out Spree's, so there is an abundance of Spree parts locally, also quite a few show up on Craigslist, but ever since that show "Pickers" and " Storage wars", everyone now thinks their junk is gold.
I think you should be able to find another Spree or just an engine quite easy, if you live near a larger town.