Engine Doesn't Match Frame Tag

[Chucker]

OK....

Took out the engine from a friends Yamaha as it was smoking bad.

The Tag says JN3-201102

The engine has JN5 stamped on it.

I want to make sure I order the right parts, I am assuming that they might have put a different engine in it.

Thanks in advance....Chucker

[Tonka329]

What is the cart model number?

[smallblock450sl]

Originally Posted by Chucker

OK....

Took out the engine from a friends Yamaha as it was smoking bad.

The Tag says JN3-201102

The engine has JN5 stamped on it.

I want to make sure I order the right parts, I am assuming that they might have put a different engine in it.

Thanks in advance....Chucker

That is the correct engine for your G14 (jn3) and was produced in 1995. The piston and rings and head gasket must be JN5's. It's a larger bore then the J38's that were used from 1985 to 1994.

[Chucker]

Thanks guys....

With this being a volunteer project...and don't want to spend $40 on a tool to use just once.

I have to pull the Clutch off of it. Stamped J3800 S . . 1

Does anyone know the thread pattern for the clutch.
Not the internal threading on the crankshaft, but the threading on the very outside of the clutch that the removal tool threads into.

I am thinking it is M14-1.5 Can someone confirm before I order a bolt to make my own tool. None of the auto stores around here have anything larger than 12mm.

Again...thank you in advance...

[Chucker]

OK...i found out where someone used a sparkplug to make a tool.

Will check it out and post results here.

[Chucker]

Tried the spark plug trick....no good, while it is the same size 14mm, the thread pattern is off. Everything that I can find says Spark Plugs that are 14mm have a 1.25 pitch.

While the spark plug will thread into the Clutch, it only goes in a few turns. So I guess the Clutch is a 14mm 1.50....we will see when the bolt comes in.

[Chucker]

OK....just ordered one from E-bay.....once I am done, it will be available to be loaned out so someone doesn't need to buy one.

[sho305]

That is the G2/9 style clutch. IIRC it is a 14mmx1 thread. I had a machinist make one for me its easy to make threads on a lathe any size you want. If you get a bolt you can also try filling the inside with grease, then put the bolt in. The grease can pressure it off when you tighten it up via hydraulic pressure. I have the print to make the puller someplace, the size it needs to be.

[Chucker]

Clutch tool came in today.
When I spin the Crankshaft, I can hear air leaking past the piston rings into the crankcase. Shall I assume that the rings need replacing ? (barely moved the compression test gauge needle).

Removed the piston and the rings. There are no markings on any kind on the rings.
How do I know what size to order ? There are 3 different sizes, standard, .25 and .50.

The cylinder wall is smooth with no gouges. Does it need to be honed ?

This is a first for me, but being a volunteer project, so I don't want to screw it up....but what are friends for.....

If anyone needs the Clutch tool....let me know....

And as always....thanks in advance for any insight and direction.

[sho305]

They always leak by hand, but if you turn the compression stroke it should resist and take a bit to leak down so its easy to turn by hand (continuing to turn the same direction through the compression stroke).

You always have to hone for new rings to seat them in. You need to measure the piston and cylinder to see where you are at far as size and wear, with a mic. (precision) Some pistons are marked oversize and some not.