Modern Vespa

New to scooters so please could really do with some help and advice on my p200e. I've stripped the engine and replaced all bearings and seals. I got to pulling the crank into the clutch side bearing and when I thought the crank was home it stiffened right up and didn't turn freely as I was expecting it to. I've read this could be because of the new bearings and seals and should loosen up when ran in. I then put the casings together and put the clutch on. It now feels stiffer to turn !!!. Please could someone help and give me some advice. Thank you.

Don't ask me how I know but this is what happens when you put the clutch side seal in backwards.

Kowalski
I'm sure I put the seal in the correct way.
The picture was the side facing the clutch.

That is the correct orientation. No idea what else it could be.

Kowalski thanks anyway 🙂

I think the problem is the oil seal rubbing. You should definitely not start an engine that is hard to turn over.

Take a look at this:
If your oil seal is the right type and properly installed, check that your crank is true. If your crank is twisted bad enough, it might rub on the rotary sealing pad.

FINYoshi makes sense. Gonna have to split the casing then again aren't i .
Suppose a new gasket is better than the damage potentially caused if I started it.
How do I check if my crank is twisted?

This happened to me when I had my SS180 engine built. It was very stiff to turn when I got it back from the mechanic. He said it would wear in fine. I did not take his word for it, took it home, and took it apart. I discovered that the crank was not true. I ended up assembling the engine myself with a new crank. After that, is turned nice and smooth, and the bike has run great since then.

The whole experience was inconvenient, but I learned how to build an engine, so it was a great learning experience after all.

Can the crank be pulled through too much?

Just opened it back up. I think maybe the webbing of the crank is binding?

Goodness. Well, mystery solved.

I couldn't hear anything grinding though. Could the crank have not been aligned correctly or do I need a new one?

Wasn't expecting that. Big end pin looks like it's moved. Check the bearing is ok and is retained correctly outboard.

Good eye, Jet-eye.

Is that blueing from heat I see around the crank pin?

I find that it's harder to tell if the clutch side bearing is properly seated on the older p cases. Later cases have a more substantial shoulder for the bearing to seat in. I think it aligns it better.

I suspect you have a crank that is out of true. You can measure it with v-blocks and a cheap dial indicator, take it to a machinist to measure, or set it up on something to eyeball it while you turn it over. If it's really out, you should be able to see it.

I like to bolt the case halves together with the 4 center bolts, wrench tight after installing the crank and seal. Just to give it a twirl before continuing with the build.

What is the condition of your rotary pad?