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Rebuilding Red Rover, 1977 P200
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How does the stock fuel tap go back together? When the old European lever handle is straight up do the three holes on the lever line up[with the three holes on the fuel tap, or are they reversed. I have tested both ways and I can't get the fuel to stop flowing.

Of course, the tap may be defective and need to be replaced.
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How old are the seals in there at the moment? In my experience, most air leaks are easy to get to. So usually, carb box base not sealed or tightened up enough, carb is warped, cylinder head uneven/ not torqued or flywheel side rubber seal is toast. I think for every 4 easy ones i've had, theres been one difficult one so the odds are definitely in your favor!

Just think of it as youre going through your scooter with a fine tooth comb so that it will give you many years of happy service! Not just this things a pain and isnt going to be reliable!
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Don't panic. Usually it's pretty easy to set the idle with an air leak, so you might not notice it then. It's when the idle doesn't come back down from high rpm's that it's noticeable.

Revving its nuts off at start up sounds more like the throttle cable or the slide hanging up or adjusted too tight. The whole arrangement is kind of chintzy and it doesn't take much to throw it off. It usually doesn't take much to fix it either if that's the problem.

Once you get a tester together and working it's not so bad. Usually the soapy water trick nails it and it's usually not the clutch side seal. It's kind of a boring job that I'd much rather skip, but it makes it easier in the long run. Jetting is time consuming enough but it's endless if you are fighting an air leak.
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Fatbear5 wrote:
How does the stock fuel tap go back together? When the old European lever handle is straight up do the three holes on the lever line up[with the three holes on the fuel tap, or are they reversed. I have tested both ways and I can't get the fuel to stop flowing.

Of course, the tap may be defective and need to be replaced.
Bail out on that tap.
I've got a new Piaggio I can send you for $0. DM me your address.
I can get it out 2-day by Tuesday.
Flow
Flow
Selector.
Selector.
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Thank you Ray... that would be great. I just sent you a PM
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Fatbear5 wrote:
Aw Crap!

An air leak was the last thing I wanted to deal with. I've read enough on the Forum to know that an air leak is a real pain in the ass and I don't need that right now. If it's leaking on the clutch side or the fly side I know I can fix it by replacing the seals and since I thought I might rebuild the engine anyway, replacing the bearings and the seals will fix the problem. That was going to be a future project though... now something for right now.

On the other hand, it it's leaking someplace else I want to fix it now and deal with the bearings/seals later on. I've seen enough videos to know that pressure testing is an involved process even if you already have a pressure tester, which I don't, so I don't want to go that route. I'm wondering where other likely leaks might be and if there is some other way to find them.

By the way, I've rebuild the carb and the throttle cable is set properly so it is probably the dreaded Air Leak... damn!
Pressure testing is not that involved, honestly. I just went through it on my 59 Allstate and found the leak in an unlikely spot. Only took about 10 mins to find. Building your own pressure tester is pretty easy. I'll post a pic of mine in a little bit. Only thing you may need to order is a low pressure gauge. I got mine off Amazon.
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Fatbear5 wrote:
No, it was just a piece of tape with nothing on it. I have the customary ID plate with the serial number on the steering column. As a side note, the serial number is 789 making it one of the first P200s ever built. That means that it is either a classic highly-collectable unit or a piece of shit unit that was still going through the experimental stage.

Time will tell
This mine. A 1977 P200e
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orwell84 wrote:
This mine. A 1977 P200e
Wow, another Oldie. I wonder how many 1977s are still on the road
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Fatbear5 wrote:
Wow, another Oldie. I wonder how many 1977s are still on the road
1977 is a good vintage for many things. I turned 8 years old in December, 1977.
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Hah! I turned 33 in 1977 so I can't really relate
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I turned into a human in 1977. ''Twas a good year imo
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Here's my pressure testing set up:

Blood pressure cuff hose cut in half.
14mm spark plug hole compression tester fitting.
3 hose barb.
Low pressure gauge from a blood pressure cuff.
Brass junction fitting.
1.25" expansion plug for the exhaust hole.

We're making carb box plates to block off that hole too over in my thread "Anyone have any interest in making…"
I used an old carb with a piece of adhesive backed rubber gasket. It held the air fine but it tore around the screws already after one use so I think the plate is a better idea.

Pump it up to about 6psi, if it holds air right then, come back in 30mins and check if the needle has moved. If not you're golden. If it has bust out the soapy spray bottle and go hunting! Shouldn't take long to find the leak once you know you have one.
Cheap and useful.
Cheap and useful.
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I borrowed a leak down tester from S. January but still haven't found the leak. The flyside seal is holding and I'm not seeing any bubbles around the base of the cylinder so I'll check the clutch side next.

I'm guessing that there needs to be NO leakage in the system. I started at 5 pounds pressure and 7 minutes later I was at 4 pounds. I was down to 2 pounds after 20 minutes so it looks like I have to keep looking.

I tried posting a video of the flyside seal but it doesn't seem to be working.
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That all looks good. Have you checked any of the other common spots? Warped carb? Loose carb box? Stuck throttle cable?
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Yes MJ, I've checked those and they look good. I understand that I should also remove the clutch and check under there but I'm not exactly sure where to look. I'm thinking that as long as I've gone to the trouble of removing the clutch I might as well remove the engine and do an entire rebuild. That way I can replace all the bearings and seals and have done with it.

On the other hand If the air leak is kinda slow (like mine) and the throttle and slide are functioning properly, if there is something else that causes my engine to race. It's perplexing.
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if the clutch and cover are on you can still check for air past the clutch side seal by spraying soapy water on the vent at the top of the cover.
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I couldn't get my carb box to hold pressure for much longer than you. My pressure test without it was good.

It's as good as I can get it and I don't think it will make any difference. You might want to do your check without the box.
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I never did find any air leaks so I'm just going to go ahead and replace all the seals. I was going to tear down the engine anyway so it's not that big a deal except that I wanted to do it later.

I've removed the clutch and the hub wheel and it all looks pretty good in there so far. I'll split the case next and then see what else needs to be done (replacing the shifting cross is a given).

Sorry abut the "Lambretta" the engine stand came that way.
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When bolting together the two halves of a split rim do you include a flat washer or just a lock washer and nut.?
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Fatbear5 wrote:
When bolting together the two halves of a split rim do you include a flat washer or just a lock washer and nut.?
There isn't room for both washers so you just use a lock washer. 2nd option is to use a flat washer and a nylock nut.
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Thanks Whodatschrome. That DOES make it easier
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Fatbear5 wrote:
When bolting together the two halves of a split rim do you include a flat washer or just a lock washer and nut.?
I use a flanged nylock nut.
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Replacing the seals on #568 (formerly "Red Rover") is part of the 4th engine rebuild I've done so I wasn't expecting any surprises. I should have known better.

Everything was going fine until I got to the part where all the instructions and the videos say "gently tap out the crankshaft." Bullshit! I had to beat hell out of the shaft to get it out. I used an old clutch nut of course but also had to use wedges and a deep socket to finally get it out. I destroyed the clutch nut and did some damage to the crankshaft threads so now I'm concerned that I might have bunged up the main bearing or even the crankshaft. Hot Rod Al is going to take a look at them and give me his recommendations.

If I have to replace the crankshaft, I'm wondering if I should upgrade to something but I don't know to what. Any thoughts? If I do, would I also need a new cylinder, head and piston?
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If you really whacked the crank getting it out, it may be out of alignment and may just need a slight adjustment to get it back to true. The threads are usually pretty hearty and may just need freshening up with a file.

If the crank is toast, don't bother upgrading to anything. Just got a stock replacement, a new clutchside seal, new piston circlips and wrist pin. Crank should come with the little end bearing.

Youre not a racer so there's no need to upgrade the cylinder. Use the old and save a few bucks where you can.
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Fatbear5 wrote:
Replacing the seals on #568 (formerly "Red Rover") is part of the 4th engine rebuild I've done so I wasn't expecting any surprises. I should have known better.

Everything was going fine until I got to the part where all the instructions and the videos say "gently tap out the crankshaft." Bullshit! I had to beat hell out of the shaft to get it out. I used an old clutch nut of course but also had to use wedges and a deep socket to finally get it out. I destroyed the clutch nut and did some damage to the crankshaft threads so now I'm concerned that I might have bunged up the main bearing or even the crankshaft. Hot Rod Al is going to take a look at them and give me his recommendations.

If I have to replace the crankshaft, I'm wondering if I should upgrade to something but I don't know to what. Any thoughts? If I do, would I also need a new cylinder, head and piston?
I did the same thing with a VBC drive shaft running the impact wrench the wrong way. Really buggered the threads. Local machinist saved it for about $20. I don't have thread files or dies that size.
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MJRally wrote:
Youre not a racer so there's no need to upgrade the cylinder. Use the old and save a few bucks where you can.
Yeah, I'm not a racer… definitely! In fact, my riding style has been described as "Old Man Wimpy" so I'll stick with the stock crank.

Hot Rod Al checked the crank to make sure I hadn't bunged it up pounding it out and after a little tweaking it is now True... and it's also installed in the case. He checked out everything else and didn't find any problems except that the main seal had just been installed backwards but some idio… oh, wait a minute, that was me. Anyway, he fixed that too so now that I've got a new cruciform and a few other things, I'll start putting the engine back together. Hopefully, the new seals have eliminated the phantom air leak.
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Is this right? I don't remember exactly the sequence of spacers for the layshaft. I think that this is the right orientation but I want to be sure before I bend down the appropriate securing tab and I can't find any diagrams. Help please.
Spacer with tabs
Spacer with tabs
Second spacer
Second spacer
Tab will be bent over nut
Tab will be bent over nut
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Turn both 180...
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The fold over washer is good, the spacer- flip over so the soft edge is towards the crank, then nut. Play with the rotation so that it doesn't interfere with the clutch cover.
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Fatbear5 wrote:
Is this right? I don't remember exactly the sequence of spacers for the layshaft. I think that this is the right orientation but I want to be sure before I bend down the appropriate securing tab and I can't find any diagrams. Help please.
And don't forget - first tighten the clutch cover and then layshaft nut.
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Thanks MJ... that works better
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roland87 wrote:
And don't forget - first tighten the clutch cover and then layshaft nut.
Why is that Roland... to make sure that the cover clears the spacer?
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Fatbear5 wrote:
Why is that Roland... to make sure that the cover clears the spacer?
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Thanks Roland... I had no idea. Good stuff!
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Fatbear5 wrote:
Wow, another Oldie. I wonder how many 1977s are still on the road
I have #963. Also registered as a 1977. Sold originally in San Diego. I still have the license plate frame
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Iamthegump wrote:
I have #963. Also registered as a 1977. Sold originally in San Diego. I still have the license plate frame
That's cool. I wish I knew the history of my '77
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Damn, I replaced the three seals and reassembled the engine and I STILL have an air leak somewhere... and I can't find it. No bubbles anywhere.

Anyone have any thoughts?
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Did you test your air leak tester for leaks? Or under the plug maybe? I've forgotten to check under the plug before and had a leak I couldn't find. It was the plug.
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Yes, as far as I can tell, there are no leaks around the leak tester… Either at the carburetor, and or at the exhaust port. It's hard to see in the base of the spark plug, but I am not finding any bubbles there either.

I am really at a loss as to what to do next.. Especially since the leak appears to be a significant one. It loses pressure fairly quickly.… Even more quickly than when I replace the seals. I am really stuck!
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I had this issue -- rebuilt the engine and still had an air leak. I went over again and again with the soapy water and tightened everything up again, including the cylinder, and it improved but I still couldn't get a perfect test. Ultimately it was the tightener on the rubber plug I used on the intake pipe. I swapped this out and found I had it air tight after all.

Barring that, did you put the clutch cover or stator back on? You can at least verify that you aren't leaking at the seals. Soapy water on the flywheel side seal and motor oil over the clutch side seal (without the drive gear on, so you can see the bearings).

I had to walk away from it 10 times and come back later after I cleared my head. Unless something is catastrophically wrong inside (which you would have seen? -- don't let me put conspiracies in your head) it's leaking from some place you missed.
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