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Discussion Starter #1
Hello all,

I am getting ready to attempt the dreaded plastic cam replacement in my "new to me" JD 345. It currently has around 860hrs and runs like new. I want to replace the plastic cam BEFORE it gives up. I purchased all the needed parts today and was just wanting to get any tips or ideas from anyone who has done the job before.

My tech manual is already on order and should be here in a few days.

Thanks for any help !
 

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Lee,

While we all know of the "dreaded" cam replacement, I'm not sure how many of us have intimately been involved with a replacement. Please take some pics through the process and then post them for other members.
 

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My Kubota's got the same engine with about 350hrs. No problems yet (fingers crossed). I recall seeing a pretty good thread on this over at Weekendfreedommachines.com. Seems to me that the biggest headache is going to be removing all the extraneous junk such as coolant, hoses, radiator, wires, etc, etc. If you've got any small engine experience, I'm sure you'll be fine. Good luck. Take pictures.
 

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Lee, I think that you are pretty brave, perhaps more so than wise. I understand that these cams routinely last 1,100 to 1,500 hours. I am more of the position not to fix something when it is not broken. Even more so when it would break without breaking a slew of other parts. Are you afraid the repair would be more complicated when you wait for something to go wrong? Or is it just that you have the time now and don't like surprise breakdowns? Or do you have symptoms that make you fear that failure of the cam is imminent?
 

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Discussion Starter #5
The reason is simple, prevention of a potential catastrophic engine failure and more difficult repair.

From what I have been advised my some other owners and techs, when this cam gear decides to go (not if), it could take out all the other "plastic gears" in its way. In addition, the possibility of bent valves and not to mention the mess it makes inside the crankcase with all the little pieces.

I plan on keeping this machine for a long time and after seeing other machines (junk in my opinion) out there in my price range, it only makes sense to go ahead take care of the problem now. Peace of mind if nothing else, plus it gives me a chance to learn something.

From what I have been told this engine has around a 2000+hr lifespan, hopefully I can get close to that with the new cam and all the little incidentals that I will replace while in there.

I have the engine out and on the bench now. Just waiting on the tech manual before opening it up.
 

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I applaud your enthusiasm and replacing the cam will give you piece of mind. It's called risk reduction... Also you get a chance to "become one" with the unit.

-gh
 

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Not sure what year they changed it, but all the GX345's have the updated cam. Maybe when they bumped it to 20hp??

-gh
 

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Lee, I do agree with the satisfaction of doing a job right and the bonding that you will have with this machine, if you make it your own with a substantial operation like this.

You will definetely have a bigger smile on your face when this engine purrrs like before. It is a great engine. I had the same in my old 320... Only heard the mower deck, the engine was so quiet.
 

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I applaud your enthusiasm and replacing the cam will give you piece of mind. It's called risk reduction... Also you get a chance to "become one" with the unit.

-gh
I think its definitely cheap insurance. Just be sure to take a lot of pictures set the digital camera to macro and get the closeups to help you get it back together if need be. You can do it.
 

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Discussion Starter #11
Thanks guys for the replys. As I posted earlier, the engine is out and on the bench. Yesterday and today was spent cleaning the engine and frame. While cleaning the frame, I thought why not just take a few more parts off and prepare the front part of the frame for fresh paint while the engine is out? Well, I did just that. I spent most of the day yesterday removing parts, sanding and taping up what I didn't want green.

I ended up removing the entire steering and dash assembly (sounds and looks alot harder than it actually is) in order to paint the battery tray properly and make painting the front frame easier.

Today I applied the fresh paint and was pleasantly surprised at how well the JD brand "rattle" can of AG Green did. It looks very nice.

The engine is just sitting there until the shop manual and "inch pounds" torque wrench arrives.

Here are a few pics.
 

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Lee,

What an interesting post. Please keep the pics coming in!
 

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Lee, thanks for the great pictures. I want to apologize for having any doubt about this job. You clearly are qualified to do this and will definitely feel better when the motor runs again. Very neat job!
Keep the pictures coming. This is going to a very interesting story for all of us.
 

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Lee, I hate to say it, but that engine pic is almost pornographic! More, more!!! :biglaugh:

:bannana: :bannana: :bannana:
 

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I believe in 1996, Kawasaki switched away from the plastic gear.
 

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Any Kawasaki 18hp liquid cooled engine (FD590V) manufactured before 01/98 has the plastic gear. My Kubota TG1860G was manufactured in (can you guess) 01/98. So it appears that I'm on the so-called cusp. I've done some research on the engine serial number and it appears that I may have the plastic gear, but there's only two ways I think I'm gonna confirm that. Either catastrophic failure of the gear, or cracking the crankcase open myself. Since I'm only at 350hrs, I think I'll just wait it out.
 

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Discussion Starter #18
Update: Didn't get to do alot this weekend. I did change out the camshaft, inspect some things and clean inside the crank case some.

That Mobil 1 syn is the cats meow. Take a look at inside the case. Yes, I did clean it, but basically wiped it out. No cleaning agent or solvent was used. For having 860hrs, I am very pleased.

I have decided to replace the governor arm and seal while it is relatively easy to get to. The governor arm has a small indentation where the governor pushes down on it when operating. This may or may need replacing, but it is very inexpensive and it is being replaced.

I am just taking my time because I really don't need to use the machine right now.

Hopefully I can get the parts this week and finish the engine this upcoming weekend. Stay tuned.
 

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Is this an "interference" engine? Meaning that should the valves stop at full lift, and the piston comes up, it will make contact.
 
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