Dave's 1650 Project

[Matt G.]

You can get that fender pretty close with a large crescent wrench, a BFH, and an anvil (or large wood block, piece of railroad rail, etc) and no heat. I have never used any heat when straightening a piece of thin sheetmetal, as it's too easy to melt or otherwise distort it when hot.

[ACecil]

That was a great idea, Dave!

[CC1650Dave]

It's been a few weeks since I've done any updates on the K341 reassembly. I've accomplished a few things lately, but progress has been hampered by waiting for parts and such.

So we're at Step 3: Install Tappets & Camshaft

I had marked my tappets for exhaust and intake, but it turns out that they're the same in the K341 anyway. <Edit 10/25/11> You'll note that in the following posts, it is recommended that you keep these where they came from. In fact, one member says it messed up his engine to have them swapped. So mark your tappets when you remove them on engine breakdown, and put them back where they came from.</edit>




Tappets in place:




The camshaft goes into place, and the shimming washers are placed between the camshaft and the bearing plate side of the engine.





Insert the camshaft pin from the bearing plate side to the PTO side and check your camshaft play with a feeler gauge. Add or remove shims to get it in spec. In my case, I had to order an .010 shim and wait a few days because I had too much play.





Then I drove the pin to the spec for the K341, which was .300 deep (pretty much so it's flush on the PTO side.)








Easy stuff so far...

[CC1650Dave]

Step 4: Install Balance Gears

In case you haven't heard it here yet, or anywhere else...

Save yourself some trouble, and pitch your balance gears in the trash can. In my case, there were no balance gears in my K341. I'm not sure if they had been removed, or if they were simply not there from the factory.

You'll note that there are 6-7 whole pages in the service manual dedicated to installing these gears. It's easily the most complex procedure in the reassembly. All kinds of timing issues, etc. And they're not needed - in fact, they're often called "grenade gears" because if you don't take them out, they may find their way out (the side of your block) sometime in the future.

[Methos]

Awesome job Dave! Sweet pics as well!

[CC1650Dave]

Step 5: Install Crankshaft

I had some difficulty understanding / finding the alignment marks to mate the crankshaft and camshaft correctly. In hindsight, it was pretty obvious, but the images in the service manual were horrible.

Here is the mark on my crankshaft circled in red:




And the mark on the camshaft has yellow paint on it (it's a little round divot)




I've asked several times if this or that was any indication that a PO has been inside this motor, and every time it's a "not necessarily" - but what about that yellow paint on the camshaft?

It should be noted here that there was a two-piece camshaft pictured in the service manual, and it requires some matching of timing marks, but mine did not. It was a one-piece unit:



Anyway, here they are mated up. I had to gently bump it into place using a rubber mallet, because the shaft goes into the bearing snugly. You can't really see the crankshaft mark now, but trust me...they're in time.




This was a good time for me to get out all of the hardware that I bagged during engine breakdown. I cleaned them all in mineral spirits earlier. Now I grouped and matched them up on a nice clean piece of plastic. It'll make the reassembly go much smoother:

[Methos]

Awesome! I've really been enjoying this thread!

[CC1650Dave]

Step 6: Install Front Bearing

I never took the front bearing out of the bearing plate. I would have, had I a proper tool to get it out. It turns out, you're likely going to reuse the main bearings anyway, so unless it's bad, no reason to remove it.

Step 7: Install Fuel Line and Wiring Harness

I dunno what variation of a Kohler engine would have a fuel line step here, but it doesn't apply to the K341. And as far as the wiring harness goes, you only really need to run your points-to-coil wire along behind the bearing plate. And I recommend that you thread it through after installing the bearing plate.

I tried putting it in place first, and it worked well the first time. But I had to remove the bearing plate a few more times to get it shimmed correctly, and one of those tries yielded a crushed points wire, as it found its way down between the bearing plate and the block. Also destroyed: One bearing plate gasket. Another five day delay, another seven bucks...



Step 8: Install Bearing Plate

If your stator is still installed (there isn't a reason to remove it on breakdown, unless it needs replacing) you'll want to unscrew it so it hangs free and allows access to the bearing plate bolts.

The manual recommends cutting the heads off two bolts and slotting them to make this step easier. I happened to have two 3" lengths of 3/8" threaded rod sitting in my box that I had used when I removed my flywheel. They did make it easier, and they didn't need screwdriver slots. You can simply grab them and turn them in / out with your fingers:



I didn't get any pics of this, but then put your gasket on the bolts, followed by the paper spacers that will determine your crankshaft end play (by moving the bearing plate farther from the block, increasing play.) I didn't make note of how many were in there on disassembly, so I had to go with trial and error to get the crankshaft play correct. It's a pain because you have to tap the bearing plate back off the crankshaft, which usually draws your crankshaft back out of the motor, and out of its timing marks with the camshaft. Try to remember to make note of how many spacers were there on takedown, if you can. It'll save you time.

I then used two 3/8-16 bolts that were 1.5" long to draw the bearing plate up to the block. The ones that actually bolt it to the block are too short to reach the threads, so this is a nice way to draw it closer without having to beat on it. Just alternate between the two bolts, tightening gradually - one, then the other, and again, until the bearing plate is drawn closer.

The bearing plate is then torqued to the block.

[CC1650Dave]

Step 9: Install Oil Seals

Now it's time to put the main seals on the crankshaft. The service manual calls for a special tool here that I did not have.

The bearing plate side seal measures 2" diameter, while the PTO side is larger. I don't remember the exact number but it was a little less than 2.5". So I needed something that was just a shade under 2", and another piece around 2.25" diameter. I took my calipers to the store with me.

In the plumbing aisle, I found some fittings for 1-1/4" PVC. The OD on the female part was a perfect 1.980" diameter. I purchased the male part so I could thread it in and have enough length to extend over the shaft, and for about $1.50, I had a perfect seal installation tool.





The seal on the PTO side is much wider, easier to find something to match up with. I picked up another piece from the PVC fittings that measured about 2.25" OD. Didn't get pics of that one, but here's the seal getting ready to install.



Total cost of all seal installation tools was about $2.25.

Driving these seals in to their specified depth is a bit hairy - Both are in a tad farther than spec because I had to tap them multiple times in an effort to get them square in the hole.

[CC1650Dave]

Step 10: Install Piston Rings

I actually figured this out weeks ago, when I first received the rebuild kit in the mail - because I was kind of freaked out about it. Here's the instructions that came with the piston and rings. I was... let's just say...nonplussed.



Then I started studying the ends of the rings. You have to be sure to study them from the same angle as the image - that is to say, holding the ring in the proper orientation and looking at the proper end. I took pictures of them to study against the image.

So here we see a ring with a 90 degree square notch in it, but it doesn't match up. That's because I was holding it wrong:



Flipped it over, and now it looks like this:



It's a match for the middle (oil scraper) ring - the last one in the row on the "instruction" sheet.

Here's the other one, a match for the top (compression) ring (2nd image top row)



And the bottom (oil lubricating) rings are obvious, the expander and the two thin rings (I only have the expander pictured here)



There is quite a bit of stuff on installing rings halfway down this page, most of it very helpful, some of it a bit confusing.

I purchased this ring expanding tool

and ring compression tool

from Harbor Freight for $8 each. I actually only used the expander partially, and found it easier to start one end of the ring and "roll" (for lack of a better word) it into place by going around the piston and bringing it down.

The bottom set goes on first. And of that set, the expander goes in first. It has a "seat" on the backside of it that the two smaller rings rest on, so it must go in first. Don't overlap the expander upon itself, it's ends must butt up. Overlapping would make it fail.




And here's the middle ring installed.




I didn't get any pics of the top ring installed, but you get the idea. I staggered all four of the rings at 90 degree intervals.