What happened to my K341-AQS?

[dvogtvpe]

if you want to get the aluminum off get some muriatic acid and soak the crank journal in it. it'll eat it off . the acid is only like $10 or $15. use in a well ventilated area and keep a bucket of water near to neutralize it in case of a spill. We use that method allot to get aluminum off of the bore's with the pulling engines We build.
We've been putting an insert in kohler rods for close to 30 years. while you can use the 16 rod for this I have seen them fail. like I said earlier the rod is a weak link, if you get the Alcoa rod out of the K361 and insert that. that makes a real nice setup. doing either does affect engine balance and you should probably it balanced for long term reliability.

[machinehead323]

well i have torn it apart more. going real smooth. got the PTO and the Flywheel off with no problems. i tapped the threads and used a steering wheel puller and a ford wrench and it popped right off. i called the local small engine place and they gave me the info for teh machine shop that they send all there work off too. i called them and he seemed knowable of the kinda work i needed done. im hopping i just need a .010 under rod. i have seen people bore out the rod and put in steel bearings. it seems to me like that would be better than having aluminum on a steel crank. what is the consensus of the heard. i dont want to have to rebuild this thing again. the hour meter said 480 but seldom works, so im sure it has more than that. i will probably put in one of the analog meters like the old odometers, not stock but works and looks old. im not sure about the valves and such. i put them at TDC on compression and put WD40 around them and they bubble real bad with compressed air blown into the ports. i havent taken anything out yet to check real good. it may be just some crud that got down on the seat. once everything is torn down it will all get mic'd. looks like someone has been in here before. the screw or bolt that holds the stator wire is mia. i also have some oil seeping out of both the front and rear seals. the piston from what i could measure was .003 under service spec. the cheap harbor freight engine stand is a godsend. i could not imagine doing it without it. it was $59 on sale and she gave me a $25% off coupon. it looks just like the $90 ones from the auto stores. im sure there all rebranded.

[machinehead323]

Originally Posted by dvogtvpe

if you want to get the aluminum off get some muriatic acid and soak the crank journal in it. it'll eat it off . the acid is only like $10 or $15. use in a well ventilated area and keep a bucket of water near to neutralize it in case of a spill. We use that method allot to get aluminum off of the bore's with the pulling engines We build.
We've been putting an insert in kohler rods for close to 30 years. while you can use the 16 rod for this I have seen them fail. like I said earlier the rod is a weak link, if you get the Alcoa rod out of the K361 and insert that. that makes a real nice setup. doing either does affect engine balance and you should probably it balanced for long term reliability.

ive used muratic acid on my pool plaster to eat it off. do you run it straight or cut it with water? is the alcoa 361 rod a direct replacement for the 341 rod? what all changes are necessary to do to use it? im all about reliability. i have never balanced any engines before. most of what i have red has been brian millers website. i can research until days end but then i dont get anything done. i just need to get a reliable tractor back. i am taking a brake from push mowing right nw.

[dvogtvpe]

use it straight up. water neutralizes it. the Alcoa rod was used in a Kohler K361 . same bore and stroke as the 16 only its a overhead valve engine. the std rods are NLA. I just order the .010 under. they only made that engine for a short time.

[Maxwelhse]

Originally Posted by dvogtvpe

use it straight up. water neutralizes it. the Alcoa rod was used in a Kohler K361 . same bore and stroke as the 16 only its a overhead valve engine. the std rods are NLA. I just order the .010 under. they only made that engine for a short time.

Water does NOT neutralize acids, bases do... Like Baking Soda. Baking Soda + Water = neutralized acid.

Water just dilutes acids.

[dvogtvpe]

that's all I ever used, but I guess the correct way would be to add baking soda or a twist of lime

[machinehead323]

so i got it all apart except for the pto side crankshaft bearing. i want to take it out so i can clean teh block up real well and clean that bearing up good. i had alot of crudd floating around in teh block. the bearing seems to rotate fine and then kinda hangs up a little. like there may be something in the way. i want to clean it up good re-oil and check it out. how do these things come out. i dont see a way to get anything in on the side of the race like pushing out a regular bearing. it looks like i have to actually push on the center part on the bearing putting force on the balls. is this acceptable. it looks like that is how the factory tool does it from the kohler manual, from what i can tell. if that is how it has to be done i guess i will turn down some aluminum to fit bearing so i have somthing good to push against. i havent got the aluminum off the crank yet. i tried some easy off cleaner, but that didnt look like it did much. i have some draino gell too that i see people use. i dont have any muratic acid right now so im going with what i have and what others have said works well for them. ive had alot of stuff rust in the vicinity of the acid too. while i am rebuilding this think i think i will do a little tweeking, if it wont affect reliability. nothing major. smooth out the intake and exhaust ports. might mill the deck down to give a higher compression. just some stuff that kirt had on his website. i dont want to go crazy since this is my main mower. would doing anything like above hamper the reliability of the motor. the only real main thing would be shaving down the head.

[J-Mech]

If your going to have the crankshaft ground, and your going to have to. It's really a waste of time to worry about cleaning it up. The grinder will do that when he grinds the crank. As far as the cylinder is concerned, the nicks at the bottom have to be at least cleaned up. Boring it is your choice. If it was me, knowing how long these motors last I would do it all right and never do it again. You keep mentioning "steel" bearings. Actually, engine bearings are babbit coated brass. Some are babbit coated steel. The engine was designed to run the aluminum rod to the steel crank and it lasted 40 years or so. What I'm trying to say is, leave well enough alone. Don't change it. Go back original. If done correctly, it will run another 40 yrs. Just my 2 cents.

[machinehead323]

im always trying to make it a little better than before. sometimes it just good already. so when i was tearing it apart i sprayed wd-40 over the valves at TDC on compression and blew air in the ports. i had alot of bubbling around them i take it as it leaking. i think i will clean it all up and put them back in to check that there wasnt some carbon in the way. the valves look pretty good to me. i will post some close ups of them later before cleaning. i see stellite and regular valves. so how do i tell if they are stellite or not. the only time i have heard of stellite was in machinegun barrels. i see some writeups talk about just relapping them and some say that is quick ie not right way to do it. i dont plan on ever rebuilding this engine again so i want to do it right.

ETA: since im in here im cleaning all of the exerior parts up too. what is a good paint that can hold up to temps. ive never mixed up hardeners and pigments. i have sprayed on some gun refinishim paints that have to be baked on like duracoat and norells moly resin. im doing teh block, tins, everything

[Maxwelhse]

Originally Posted by dvogtvpe

that's all I ever used, but I guess the correct way would be to add baking soda or a twist of lime

Sorry, but I can't resist... Citrus fruits are acidic...

I'm not trying to rub your fur wrong, I just want to put as much accurate information out there as possible for others. I'm not above correction either.

Anyways... The acid trick sounds useful and I may give it a shot the next time I have something of this nature.

Back on topic.. I agree with J-Mech... The machine shop is going to "clean" it, and charge you for it, no matter how clean it really is. That said, the stuff I've gotten back from machine shops in the past has been worth what they charged me.

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Has anyone ever tried just lapping uncut valves back into the old seats? I wonder what that might gain?