2006 Yamaha G23a Low Compression? Need Rings?

[trialsguy]

Hello, new to forum, I just picked up a 2006 Yamaha g23a golf cart with low compression and may need rings. I am trying to figure out a few issues, one is the key ignition and the lights. The previous owner said he had to make a key for it and it turns hard to the on position but I cant feel a second notch or location for the lights to come on so I am wondering if the key is not working properly allowing the ignition to turn farther to turn on the lights.

It smokes pretty bad and the PO said that the carburetor use to flood and he thinks the gas got in the oil. he said he replaced the rings but he thinks a valve stem seal if they have them might be leaking.

I had a quick look at it but soon realized I needed to take off the front body piece to get to the ignition switch but before I went through the trouble of all that I figured I would do a internet search to get some info and that's when I ran across this forum so here I am with hat in had asking for your knowledge and guidance.

Thanks
Bob

 

[trialsguy]

update:

The ignition switch is messed up and I can use a flat bladed screwdriver to turn the key on and also the lights, with the key in it it is so flimsy that I cant get it to turn over to the lights. It is messed up I know but I think for now I am going to make a flat key for it that will operate better then the make shift key that is in it now.

How hard are these engines to re ring and go through?

I have rebuilt older style 2 strokes and 4 strokes and this engine doesn't look too bad as well but in case I thought I would ask in case there was a couple of gotchas that I needed to look out for.

The clutch pr something makes a pretty loud knocking sound that sounds really similar to a rod knocking but I don't think it is. Do the clutch assemblies ever make noise?

Thanks
Bob

 

[trialsguy]

Sorry I keep piling up questions but I had a little time tonight to mess with the cart. The clutch assembly has a grease sert so I hit it with the grease gun. It looked dry to me, I was hoping that it might take care of all the racket or knocking that takes place when you hit the gas pedal.
The knock speeds up as the RPM increases but it also goes away once you get close to top mph speed.

Doesn't seem like the clutch pack maybe it is a rod knocking or maybe the rear transmission I don't know but I thought I would put it out there in-case someone has run across this before

Thanks

 

[dirtysouth]

Welcome to the forum Bob.
The engine has valve seals, but I doubt they are the cause of any serious smoking.
It sounds like this U-Max has been worked pretty hard. The Yamaha G23 shares the same base suspension as the G16,19. The engine and drive components should be the same as the G22 (G-Max).
The forums a bit slow with the holidays. Some of the Yamaha guys will show up soon.

 

[trialsguy]

Cart was running crappy so I pulled the carb to give it a cleaning. Before i cleaned it up it was hard to start and didn't run smooth and had to choke it almost every time I started it.

Now it runs really nice as long as you ease into the gas pedal but if you floor it it falls on its face and catches up when you let up on the gas pedal. Runs nice but does have the hesitation. not too terrible actually but thought I would throw it out there.

There is a screw on the carb that I didn't pull out as it has a guard on it that prevents it from turning one way or another and I didn't want to break it so I left it in, it will only turn about a 1/4 turn so I am wondering if this will eliminate the hesitation if I turn it a bit



Smokes like a mosquito fogger which might be handy around the farm. No oil in the air cleaner so I guess that's fine but thinking about pulling the head and changing out the rings and at least having a look at the inside of this thing.

Rear axle grease is gray indicating oil in the lube so I need to drain it. My question on this issue is how do you drain the rear axle grease I didn't see a drain plug at a quick glance.

I know lots of questions, I am attempting to use the search function but I am not getting any good hits, probably not using it correctly though.

Thanks

 

[dirtysouth]

Nubs?

 

[Nubs]

Hey Bob

It sounds like the knock is a bad rod and the smoke/hesitation is from wore rings, low compression will also add to the hard starting. not many of those engines come though here but the ones that do all have bad rods. once the gas thins out the oil the journal surface of the rod gets scuffed and will wear fast, i would check the compression but i think a rebuild is in your future. the rivets that hold the cam gear on are also known to work loose, may want to check that if ya crack into it

 

[trialsguy]

I will check the compression tonight when I get home, I had to borrow back my compression checker from a buddy Where should the compression be somewhere over 150 psi I would think?

Any free online resources for a manual that anyone may know of so that I can look at the engine before I tear into it.

Starts right up now and smooth running other then the hesitation that occurs when I mash the pedal down it will catch up once I ease up.

I look at this engine compartment and wonder what other engines would bolt in without too much hesitation. Bums me a bit as I had a 18hp kohler then ended up trading it for some car parts

Thanks

 

[trialsguy]

Was able to check compression at lunch and it ran right at 100psi then I squirted oil in the cylinder which raised the compression to 130 which seems a little low still but it does tell me that I am losing compression through the rings.

 

[Nubs]

I think you have your answer anything under 140 dry is gettin' pretty weak, a re-ring and new rod and she'll be gold

 

[Nubs]

I'd spend the extra money and bore it if you plan on keeping it awhile

 

[trialsguy]

I got a buddy that runs a small engine shop here in the kc area maybe he can hook me up with the boring and parts, if not where is the online go to for parts around here? I will have a look at it soon but dang it is so handy around here right now getting firewood and stuff, even the kids are eager to go down to the wood stack if they can take the cart. I hate to take it out of commission so soon after getting it

 

[trialsguy]

I have found standard size piston, rings and rod but what if I need a different size I havent found a place that shows them online anyway.

 

[Nubs]

I think the g22 is the same but you should check to make sure. I found 0.20 over also somewhere not to long ago but i think they were around 140.00

 

[trialsguy]

Ok I am starting to get the feel for this vehicle and how everything operates. I love it and I have a couple different means of transportation around the farm and even with it being super smoky I will head out with it, of I have questions though

1) are the rods sized or can I get oversized rod bearings I havent found a good resourse for this info just yet.



2) I am not 100% sure the knock is a rod but more then likely it is but I notice under load say mid to full throttle up a slight incline it will go away but as soon as I let off or just putt around very loud knock sounds and it increases and decreases with the engine rpm.

What I need to do I suppose is get the bed tilted up and in neutral and try and run the throttle while leaning over the engine to determine where the knock is located, the PO thought it was a clutch but I am pretty sure its not the front clutch.

 

[trialsguy]

For the knock determination I am going to pull off the front clutch and belt and if it still knocks, presto! I have determined that it is indeed a rod knocking

 

[Nubs]

No over sized rod or bearing shells, there cast throw away parts. most times the crank can be cleaned up and a new rod can be installed.

 

[trialsguy]

alrighty, Still wonder though if I have to turn the crank or clean it up will I be able to find a 20 over rod, I haven't found one available yet but honestly I haven't called around only looked around on the net.