Modern Vespa

I removed the engine from my 2006 LX 150 to work on as a winter project. It's running pretty well, but I thought it was time to give it a deep inspection, cleanup, and replacement of any worn parts.

I was thinking to split the cases just to have a look at bearings etc. There's a seal plate that requires an expensive special tool to install. If I split the cases, is it required that I replace this seal? This seal is not leaking currently, so I don't want to create a problem I don't have.

short answer, yes.

long answer, [click here for subscription with special one time deal]

why do you want to inspect your bearings? it's not like you can replace them.

I mean, you can it's just a tremendous amount of work and money.

how many miles are on the motor? why do you feel like the bottom end need attention?

Thanks, greasy.

The engine has about 13,500 miles on it. I don't think the bottom end needs attention. I just figured that while the engine's out and in my warm basement, it would be interesting and worthwhile to open it up. It's a long winter in Toronto!

But it sounds like you've just talked me out of it!

I thought if the seal was in good shape, there might be no problem pulling the crankshaft through and then gently just putting it back later. But I guess that's not the case

sounds like you need a vintage bike

that side of the case houses the timing chain and oil pump, which drive sprockets ride on the crank, so to assemble that you need to have the seal off for access. I *guess* you could maybe do it if you were super patient and meticulous, but man that would be some serious ship in a bottle work. and if you mess up, the possible damage would out weigh and savings.

the older style seals were "serviceable" in that you could remove and replace them and there were o-rings and lipped oil seals available. but then new style with the vulcanized seal is a one shot deal-- mainly because you can't remove them without totally ruining it.

at 13.5K I wouldn't bother with opening it up unless it needed major surgery. the seals and gaskets alone are around 100 bux and then you've got oil and a filter on top of that. no thanks!

I would be taking greasys advice seriously, don't go there, just make sure its serviced on schedule using the correct lubricants. That's just creating a lot of work for little or no gain.

Lol, agreed. I'm impressed with your adventurous nature...though winter in the north will do that to a guy.

I guess everyone's got different tolerances for a challenge. I've been to places in my scooter I never imagined going, but there was a problem and a goal. It wasn't exactly fun, but rewarding....first finding out I can manage not to do overwhelmingly stupid things (I need confirmation of that occasionally ) but most importantly solving a problem.

Diving into an apparently good engine is an interesting exercise, but the question is what are you going to do when you get there? Are you ready to replace parts that show a bit of wear? That can be a bit of a rabbit hole, and expensive.

But hey, there are worse ways to spend a winter. I'm off to annoy myself with jigsaw puzzles for a bit...

If it ain't broke fix it 'til it is.

To be fair, I went down this road because I think the engine does need some attention - just not in the bottom end. I've noticed some oil in the airbox and somewhat harder starts. And when I got the plastic shroud off the cylinder, thick caked on oil (is that what a leaky head gasket looks like on an air cooled bike?). So some inspection of the top end is warranted.

I thought I'd peek at the bottom end too if it was just a matter of a gasket or two. But $300 of one time tools and special seals is probably a bridge too far under the circumstances.

^^^^^^tool's don't count$$$^^^^^

You buy that special tool because you need it for you tool box, work shop or what have you. It's important and necessary!!!

Then 20-25 years later you come across it and barely have a clue what it's for. This is especially true if you are not "brand loyal".

DAMHIK.

When I needed to replace the right half of the crankcase on my GT 200, I was able to do it without pulling out the crank. I replaced it with the Right side case off an ET4. So you can R&R the right side without removing the crank or compromising the giant seal, but if you take the crank out of the seal, go with what Greasy said.

How common a repair is replacing a seal?

Most likely just the rocker cover.

not very common at all.

oil in the airbox is fairly typical. cleaning it out and ensuring that the breather is clear and hose is undamaged should be part of routine maintenance.

these motors can push a little bit of oil, so that's not something I'd be terribly concerned about. usually it looks like the head gasket but it's actually the valve cover gasket, but either way cleaning all that up and refreshing isn't the craziest job. at the very least you have it cleaned up and you can ascertain where it is leaking from and make a plan of attack.

but if you're gonna pull the head, why not go whole hog and snap on a 190 while it's all apart?

I've done a few RH cases. if you leave all the transmission together and you're careful it can be done. but man, is that an undertaking!

anyway, the key is the timing components. once you've removed the crank it's damn near impossible to get all that back together with the seal in place. I'm not saying it can't be done, but I'm not going to try it.

Photo attached. How does it look, gents? Yes, may do

that's likely schmoo from oil changes residual or some such from other leaky bits. give a poke around and see if you can find a source at the head itself. there should be a witness line...

Thank you.

Thanks, again. I couldn't find an obvious source. You're probably right on it just being years of schmoo, but there was quite a bit there. I opened it up anyways to be sure.

I did find a loose stud and a gouged cylinder mating surface, so maybe?

I thought it would be cleaner to make a new thread, so I posted photos there: LX150 engine apart - anything to worry about? (Post 2657718)