G9 Engine rebuild

[HHP123]

Hi folks. I am a long time lurker and new poster on the forum.

My 1993 G9AJ is burning a lot of oil, 1/2 quart in four to five hours. Also, I believe my clutch, (primary sheave?), is going bad in that it makes a metalic screeching sound starting out, seems to be slipping, and the acceleration became very poor.

Certainly, I will appreciate any advice regarding this endeavor. I plan to by the engine rebuild kit from Buggies Unlimited, will I need additional items?

It looks like I will need to purchase the clutch puller tool, too. It looks like a long bolt that was turned down on a lathe and costs $43.00. My manual has a sketch of a tool that looks a lot different. Suggestions or options here?

The new piston and rings are noted as being 0.50 mm over size. My guess is that normal wear and honing will take care of this.

With regards to the clutch, I notice on the BU web site they have some replacement parts for the clutch as well as the entire assembly. I think once I get it off and inspect the internals I may be able to address the noise and slipping problem. If anyone can offer advice or experiences about this I would be grateful.

Thanks Guys

[Mike Mac]

You need to call one of BGW sponsors about all of these concerns. Think you will be happy you did!

[TROUBADOUR]

What Mike is trying to say, in a very diplomatic way, is that BU is NOT a sponsor of this forum while there are quite a few sponsors who not only offer the same parts, but also contribute to this forum in many ways.
I have bought some things from BU, and I admire their catalogs, but ... make your own decision...

[Mike Mac]

You may have maint. related issues, that not necessarily require a rebuild. Read this whole yamaha site, and do a through maintenance program on your car before you spend big money. In a very few instances, bu has been not the best place to get quality parts.

Unless its smoking badly, you need to find out where the oil is going. A 50 over ring, goes on a 50 over piston. Which requires a bore job. Which it may need, but maybe not. Same with clutch, read this site.

Good luck!

[HHP123]

Thank you for the quick replies. Not the most encouraging news, but necessary no doubt. I will certainly patronize and support sponsors of this site in that it has a lot of great information and I enjoy reading it.

I am pretty sure of the oil burning because of the consumption primarily with the absence of visible leakage and compression runs around 100 psi or less when hot. I think that leaves rings and/or valve guides being worn. The clutch, well .... That is new territory for me.

My mechanical experience is derived from my hot rod days in the late 60's. To that end, I recognize a knowledge gap to say nothing of the memory being cloudy. Thanks for the input guys.

[jakecove1]

Mine is having same problem, when i tore it down ,it had no cylinder wear(no ridge) I ordered standard piston and rings, my piston had pretty bad scoring, and the regards to puller, i took bolt out, and clutch slid right off, might tear down first to see what you need.

[Mike Mac]

HHP, 60's hotrodder,... you'll be ok!!

Jake, need to see if cylinder is round and not excessive taper. Then hone cylinder.

[jakecove1]

I did plan on honing cylinder walls, I need to get tool to measure bore yet, Thanks for the help. I will check that

[jakecove1]

Can anyone, tell me the way to measure cylinder, i went to all car places and they had no tools to do it, i thought you guys might have an easier way.

[Mike Mac]

Jake, I would take it to a lawn mower shop or motorcycle shop or golf cart shop. Need somebody that knows what their looking at. You will spend money, and could quite possibly end up with the same situation you have now or worse. You want to just do it right the first time.