1650 Resurrection

[Greg Riutzel]

This will be a continuation of work on a K341/1650 tractor I posted about in the thread "Kohler K series shortblocks". So installation into the tractor is now finally arrived. I ran into a small hitch when I was attaching the engine to the engine mounting rails. I noticed that the rails did not want to lay flat or bolt up flat to the oil pan. The rail edges were interfering into the radius of the oil sump on the oil pan. I switched from an aluminum pan to a cast iron one. This was because the mounting holes were stripped and wallored out in the aluminum; i.e. no chance of saving it, just not enough meat left for threads of any kind. The old aluminum one had some deep chafing along the sump from the rails and I believe must of been a problem from day one. Unknown to the PO, they worked loose and hammered out. What I did was trim and bevel the edges for a nice flat fit. The bolts went in easy peasy after that.

 

[kmcconaughey]

Nice progress.

 

[Greg Riutzel]

Success! She fired off with a 1/2 second spin of the starter. It certainly seems a whole lot quieter than what I remember. I let it run about 30 minutes varying the throttle keeping around 1,500- 2,000 Rpm. Then I'll let it cool for re-torqueing the head bolts.

 

[dschwandt]

Did you do the cradle brace mod while you were at it??

 

[Greg Riutzel]

No I didn't. It's been years and this has been in the "back 40" far too long. I was thinking of the brace, but so many other things needed tended to just to get her in stock working trim. Does it make a large or noticeable difference?

 

[dschwandt]

Just helps keep things in line and tight.

 

[glippert]

The big difference is prevention of the kind of damage you found on your old, aluminum oil pan as the rubber isolation mounts wear out.

 

[Greg Riutzel]

That's the forensic thinking going through my mind. My question is I don't think they were square from day one considering the bind on the sump radius kept them from laying flat and true. Even with torqued down bolts, they would've still been in a bind and not totally flat. As the aluminum wore, the tension relaxed enough to cause movement and hole damage. I can now guarantee they are flat and in full contact and I stretched those bolts for all they're worth i.e. the torque for the grade and size. I'll definitely check them at oil changes. If it becomes a need the brace will happen.

 

[kmcconaughey]

Here's a link to the CubFAQ that has the info on the crossbar mod for the engine cradle:

CubFAQ - engine cradle brace mod

 

[Greg Riutzel]

Thanks for the link! I have two comments. 1) in the pictures I noticed in both photos of the oil pan mock-up there was some clearance for the oil sump. I didn't have any when I went to bolt my rails on. 2) The author suggests swapping top rubbers to the bottom to save costs on new ISO kits. The new ones I got from Cub Cadet won't do that. The bottom rubber is conical and goes part way into a recess in the top one. By the old ones I took off and the Service Manual picture, it seems they have changed.

 

[kmcconaughey]

Greg, yes the rubber pieces have changed a few times over the years. The main take away from that FAQ is the crossbar brace between the engine cradle rails.

 

[Greg Riutzel]

Good to know. Just how much does a K341 rattle these machines? I left out the balance gears and put on Kirk's crankshaft balance plate kit, plus the cast iron oil pan and new mounts. Overall it seems way better than what I remember. It idles much quieter but around 1,800- 2K it'll rattle the sheet metal and near full throttle for mowing I can feel it through the seat cushion. I've set the governor at 3,100 max throttle but I don't see a need to go that high. At 5 hours run time I changed the oil and so far it's all good. I'm logging hours on the few sunny days we're getting here.

 

[mgonitzke]

The engine mounts are designed to properly absorb the engine vibrations at 3600 RPM. You need to set the max RPM to that for proper cooling and so the engine mounts work properly.

 

[Paul Young]

Thanks Kraig for cradle brace info. Will be working on my 1650 in the future , installing a k 341. Thanks to others with parts and other info. I didn't mark wiring from stator for plug to regulator, figured out both wires +, magnets, crank and block ground or - . Looked at the pictures you posted. Pictures worth a thousand words and a lot of ridicules questions and typing.

 

[Greg Riutzel]

Okay, got top RPM set at 3,600. Amazing how it smooths out. Overall this is the best since I've owned it.

 

[dschwandt]

I re-built my 341 a year ago and set it at 3600 right off the bat and it is a smooth runner as well also.
I had to replace the crankshaft and sourced one w/Dave K's balance plate already installed.

Glad you are happy with it!

 

[Greg Riutzel]

Here the graduation pic. It's all together. I had the mower on the other day for a try out, and it's reasonably quieter than today's models and cuts a nice swath. I think it's the air noise I hear mostly in modern machines. It helped that I went through the mower deck some years back with spindles, bearings, blades and new belts. I probably don't need Micky Mouse ears now, but protection will keep what's left. I'm still not quite used to a 16 Hp coming through the seat and dash which is partly what started the overhaul, but it is better. I have to give a shout out to this board, Kirk
Engines, CC Specialties, Jack's Small Engine, A-1 Miller, and a host of others for parts and advice.

 

[lsheard]

Here the graduation pic. It's all together. I had the mower on the other day for a try out, and it's reasonably quieter than today's models and cuts a nice swath. I think it's the air noise I hear mostly in modern machines. It helped that I went through the mower deck some years back with spindles, bearings, blades and new belts. I probably don't need Micky Mouse ears now, but protection will keep what's left. I'm still not quite used to a 16 Hp coming through the seat and dash which is partly what started the overhaul, but it is better. I have to give a shout out to this board, Kirk
Engines, CC Specialties, Jack's Small Engine, A-1 Miller, and a host of others for parts and advice.
View attachment 141357

Looks great, I have a 1650 with a 3 point lift but the hydrologic valves in the rear end, one has the end broke off and the tractor dont drive. Thinking there might b more problems. Could use some advice. Thanks in advance.

 

[Greg Riutzel]

The best I can offer is for you to get a Service Manual, check the FAQs on this board, and post some clear fuzzy free pictures in your own thread. That way you will be well armed and the group can focus on your problem solving.