Putting the K241 back together - Page 3

rsshallop · #21 07-28-2019, 05:42 PM

Ok, now I'm having a bit of a problem with torquing down the bearing plate bolts. I have been torquing the bolts in stages, first 120 inch pounds, then 240 inch pounds, then 360 inch pounds. To that point all is good, but when I do the final torque to 420 inch pounds the torque wrench only click stops at 420 on three of the bolts. The final bolt seems to not want to torque to that tightness in with the same amount of rotation of the wrench. I don't want to force it forward on the thread as the bolt still seems to have bite and I don't want to strip it. Any thoughts? I have double checked the forth bolt and right now it is torqued at 360 inch pounds. I am contemplating leaving it at that.

rsshallop · #22 07-28-2019, 10:26 PM

Ok, I have removed all the bolts and checked the female threads in the holes with my tap. All the holes seem fine, the tap did not remove any metal and only a tiny amount of debris. I'm thinking they are good. After comparing the bolts to what is on ebay for this part (bearing plate), they they look to be the correct ones. What I don't understand is how these bolts, which appear to be grade 2 and should only be torqued to 260 inch pounds according to the manual I have for this engine then be recommended to be torqued to 35 foot pounds to fasten the bearing plate in that same manual? Regardless, I'm just going to go out and buy new bolts (probably grade 5) and try again.

rsshallop · #23 08-01-2019, 12:58 AM

OK, I bought new grade 8 bolts for the bearing plate and torquing it down to specs is no longer an issue. I've had the bearing plate off and on a few times now to make sure the end play on between the crankshaft and bearing was within specifications. right now I'm using one spacer gasket with the regular gasket and it come in at .008. (previously with one spacer gasket it came in at .016. No idea how I managed that???). Regardless, I'm leaving where it stands. Also, during all of this run around I noticed that I hadn't driven the pin for the camshaft flush on the PTO side. That has now been corrected. Next stop, get the seals on and then onto the piston and rings.

rsshallop · #24 08-03-2019, 09:43 PM

First off, I would like to correct a flagrant error in the title of my posting. What I am attempting to do here is put together a Kohler K241A, not a K241. Not sure what the difference is, but obviously there is a difference. OK, just finished installing the oil seals into the bearing plate and block. determined what the depth should be as indicated on page 12.10 of the Kohler single cylinder engine service manual K91 thru K341. Then using lots of lubrication, I very carefully tapped the seal on the bearing plate into place to a depth of .12 inches. I first used my piece of steel to tap it flush to the plate, then I used a punch to tap to the .12 depth.

rsshallop · #25 08-03-2019, 09:46 PM

Next, using the same method I installed the rear oil seal to a depth of 1/8 of an inch. Rechecked Crankshaft end play. Now standing at .007

rsshallop · #26 08-12-2019, 11:16 PM

We have had company lately, so there has been little opportunity to work on the engine until now. Checked the gap on both the compression and scrapper rings and they came in at .013. Since they were in specs, I didn't want to file the gap any larger. With lots of lubrication, attached the piston to the connecting rod, then put the rings on in order and staggered them. The piston ring combination is an A type. Next, I used the ring compressor (again, lots of lubrication) to slip the piston into the cylinder bore. I was very careful about this and the piston slipped in smoothly and without doing any damage. The marking on the connecting rod will accommodate the oil hole on the connecting rod cap to be on the camshaft side of the engine. However, the oil dipper on the new connecting rod cap is longer than what came out of the engine. I'm pretty sure this larger oil dipper will still work with what I have (K241A) and at this point I don't want to take the piston and connecting rod out, so I am thinking of getting and continuing on with a deep slump oil pan. Anyway, I am going to go ahead and connect the connecting rod to the crankshaft to see how the piston moves up and down in the cylinder. I hope there are no other surprises.

rsshallop · #27 08-13-2019, 05:26 AM

Something was bothering me about a difference I read about between the K241 and K301 crankshafts. After checking the specifications for bore and stroke between these engines, I think the connecting rod is going to have to be replaced.

rsshallop · #28 08-13-2019, 09:33 AM

OK, I have temporally connected the connecting rod to the crankshaft and cycled the piston up and down the cylinder. I don't see any problems with the stroke, so I am now back to thinking this connecting rod will work with a deep slump oil pan. I already need another oil pan anyway because the one that came off the engine was damaged.

rsshallop · #29 08-27-2019, 08:46 PM

OK, I was able to get my hands on a deep slump oil pan and have continued on where I left off. Have lightly lubricated the threads on the connecting rod and secured the connecting rod cap to the connecting rod. Lubricated the crank pin and connecting rod beforehand. Torqued the cap screws twice, first time to 342 inch pounds, backed off the screws and then the second time to 285 inch pounds. The cap screws didn't come with lock washers, so I have opted to use Blue Loctite 243 on the threads. Honestly, I don't feel real comfortable with this part of the rebuild. But, it's the best I can do, so I'm going with it. I did buy a new torque wrench for the occasion. Next, got the valves reinstalled. Made sure the springs were pointed in the right direction (tighter coils towards the top) and the keepers were rightly positioned on the notch at the ends of the valve stems. Next, I'll make sure the cylinder head is flat, get new head bolts and carry on.

rsshallop · #30 11-29-2019, 10:49 PM

hi, it's been a while since have made any progress on my Cub. Lots of other stuff keeps coming up including a lot of supporting my wife's efforts. Anyway, I'm going to try and pick up where I left off and continue to rebuild the engine (Hopefully have it ready for the spring). Tonight I worked on the flywheel drive cup, which I damaged when I removed it from the crank shaft end back in February. I used a low temp aluminum brazing rod and my propane torch to try my hand at the fix. I think it turned out OK, had to really heat the cup up a lot before the rod would melt in and bond.