Broken camshaft gear on a Confidant EZT750

[GearHead36]

These are air cooled mostly with some oil cooling. We all must keep the cooling fins clean and clear like a new engine block. If not look for engine damage like this.

Cooling fin cleaning is in EVERY engine manual out there minus the water cooled ones. A yearly must do or more often. Download your engine manual and read it.

I'm aware of the need to keep cooling fins clean. This mower is a great machine for mowing. It's a terrible machine for servicing. It's a pain to get to the cooling fins, which is probably why they were so clogged. The previous owner probably never cleaned them. Since it's such a pain to get to the fins, I decided that I'd wait, and do that during the off-season service. It had 358 hrs on it. Another 20-25 couldn't hurt it, right? I put 27 hrs on it that first season. I think that there's a good chance that when I bought it, the damage had already been done. I'm sure that extra 27 hrs didn't help things, but I doubt that is what killed the cam gear.

 

[slomo]

Since it's such a pain to get to the fins, I decided that I'd wait, and do that during the off-season service. It had 358 hrs on it. Another 20-25 couldn't hurt it, right?

Your engine, do as you wish. I would say wrong.

It's a pain to get to the cooling fins, which is probably why they were so clogged.

Yeah, not buying it. One person could have that entire engine off the mower in under an hour with common hand tools. What 4 bolts, couple belts maybe one or two harnesses and a choke/throttle cable? What did I miss?

 

[GearHead36]

Your engine, do as you wish. I would say wrong.

In hindsight, yeah, I was wrong. I should have cleaned the fins during the initial repairs.

Yeah, not buying it. One person could have that entire engine off the mower in under an hour with common hand tools. What 4 bolts, couple belts maybe one or two harnesses and a choke/throttle cable? What did I miss?

Roll bar. Bumper. PTO clutch. Fuel line. Starter cables. Muffler shield. Weight of the engine. It's a 750cc V-twin with EFI. It's NOT light. I can lift the engine straight up off a dolly, but if it's in the engine bay, I'd have to lean over it to lift it. My back won't let me do that, so I have to rig up a lift or hoist of some type.

Reinstalling the engine... there is an "Engine Shield Plate", that sits under the engine and on top of the engine mount plate. It has to be lined up to get the engine mount bolts through. Every time you slide the engine to line up a mount hole, this shield plate moves too. I discovered this time that it's supposed to have a couple of plastic push pins to keep it in position, and they were missing. I found a couple, and installed them, so now when I slide the engine around, the shield plate doesn't move. Getting the engine lined up, and mounted was MUCH easier this time.

I'm a gearhead, and I know my way around wrenches, but I admit, I'm no small engine expert. I'm sure many others here could do the job in an hour, but I don't think your average shadetree mechanic could do it that fast. I have another ZTR with a single cyl engine, no roll bar, and no bumper. I could likely get that engine out in an hour.

The roll bar and bumper are nice features to have, but they interfere with many things. In putting the engine back together, I messed up the RTV on one valve cover, and it was leaking oil. The roll bar had to come off to get the valve cover off.

Really, you shouldn't have to remove the engine to clean the fins. Since I had to take out the engine again this year, I had no problem accessing the fins. I pressure washed the whole engine. Next off season, I'm going to try something else. I'm going to remove the main shroud (the one on the top of the engine), and see if that will let me get to the fins with a pressure washer.

 

[slomo]

So you admit it was a 5 minute job LOL. Joking of course.

I bet you spent more time, fussing with that cured RTV, cleaning parts and mess, than would of taken to pull the engine. Just saying there are better sealants that don't cure hard like RTV one could use.

I don't have a mower like yours. Have no clue what it would take to clean the fins. Always 5 ways to skin a watermelon. Has to be a more efficient way to do it?? Leaf blower after every mow is a good start.

 

[slomo]

In hindsight, yeah, I was wrong. I should have cleaned the fins during the initial repairs.

There is it..... My man....... Good on you to fess up on it. I like you even MORE now. Enjoy the day.

 

[GearHead36]

I don't have a mower like yours. Have no clue what it would take to clean the fins. Always 5 ways to skin a watermelon. Has to be a more efficient way to do it?? Leaf blower after every mow is a good start.

I already use a leaf blower after every mow. That doesn't help. I can't get to the cooling fins without removing stuff.

I think the whole cooling fin clogging problem has been due to oil leaks. I've been on a mission to eliminate all oil leaks. So far, the oil leaks have been winning. The last mow gave me some hope, though. The oil level didn't drop even a tiny bit, which hasn't happened before.