K301S broke a rod today, novice needs help!

[E12Horse 2]

I have kept an Electro 12 running for the last 18 years or so and today it broke a rod. This was on a replacement engine that I have had for about 16 years. I have used the tractor for lawn cutting and winter plowing through out that time so it has been a faithful horse!

My question is where do I find parts for the repair and is it something that someone with good mechanical skills and a manual should attempt?

I already tore it apart so I can turn a wrench!

How far do I go in the replacement of parts? Up to today the engine ran strong, there is aluminium on the cam shaft, I am wondering if it can be machined and reused? The rod is shattered at the bottom but the piston and rings look reasonably good so does the cylinder wall.

Do I just replace the rod, machine the cam, replace seals and reassemble?

Any advice that can be offered I will gladly accept!

[gregg'shorses 77]

A K series service manual can be down loaded @ www.kohlerengines.com, and a OEM connection rod can be purchased at a kohler Dealer or Napa auto parts, Do you mean the aluminum is on the crankshaft? Google small engines how to remove aluminum off crankshaft, muriatic acid is needed. Part # should be 47-067-09-S standard size 47-067-10-S , But take to model, serial and spec #s with you to double check.

[SousaKerry 503]

Make sure to measure the crank journal before you order the rod. If it is egg shaped at all it will need to be turned at a machine shop. Standard rods are only available for. 010" under however there are a few aftermarket places that offer smaller rods.

Google Brian Miller his website is great for this stuff

http://gardentractorpullingtips.com/engine.htm

[E12Horse 2]

Thank you both for the suggestions. Yes I did mean aluminium on the crankshaft. I will try muriatic acid, and see how it looks, my gut tells me it will need to be machined.

I do already have a manual so I am good there.

The link to Brian Miller was great, thank you again! I will check some local shops tomorrow and see if I can line up a local resource for machining.

Should I be concerned about re-boring or just replace the rings?

[can whlvr 994]

it all depends on what you want,do want to go all the way and spend the cash(which is what i recommend)after that many years of use she will show some wear,up where o live a rebuild will cost anywhere from 350-550,doing it your self other than the machine shop costs,to bore,turn crank if needed,polish journals,grind vales if needed,if it were me i would take it tooo the shop to be measured and go from there

[MarkPalmer 81]

Any work you feel comfortable doing yourself will save you tons of money. You will need to measure the crankpin for out of roundness, as there is a reason the rod journal seized to it and the rod snapped. You can buy telescoping gauges and micrometers (that are fairly decent) cheap at Harbor Freight to measure your bore diameter, the crankpin, and most of the other parts. The cost of these measuring tools will be less than one hour of typical machine shop labor. If the piston looks good and the bore measures in spec, you can just deglaze the cylinder and install new rings- use Kohler rings with the three piece oil ring, I learned from others about them on this forum and found that they work really good on used bores to control oil consumption. If the crankpin is out of round, (most likely) you'll need to get a .010 under rod, but be sure to bring the new rod to the machine shop to they can fit it properly to the crankpin. I would remove and check the valves too. The seats and faces can look good with them installed, but you can't really see them unless you take them out. The seats rarely wear, and its easy for a machine shop to re-grind the valve faces, then you just lap them in to the seats. Salvage your original engine parts as much as possible- I have found the aftermarket parts and even some new parts from Kohler just end up being a pandora's box for more un-necessary measurement and machining. The work isn't really hard, but it can be time consuming.

-Mark-

[E12Horse 2]

Mark, thank you for the advice. I just talked to a local machine shop and he can do all this for me for around $350. He will start by cleaning up the crank journal and seeing how it looks. Then turn it to .010 under if needed. He will hone and re-bore as needed and regrind the valves as well.

It may be less if things go well but I am not counting on it. A local parts place said they can get all the parts needed but had trouble matching spec numbers. He is researching it some more.

My original was 47147C the new sticker that came with the rebuilt engine in 1996 was 7752233.

Can anyone explain the different specs and guide me toward the correct replacement parts?

I found a gasket kit for a K301 on ebay for $35 will I be taking a risk on fit by ordering it like that?

[MarkPalmer 81]

The gasket kit should be fine as they often include all the gaskets and seals used by the various spec numbers for a given engine model, and the major gaskets are all the same between spec numbers anyways. For the piston/rings and rod you'll need to wait until the machine shop measures everything to see if the engine needs to be bored oversize and if the crank needs to be ground in order to know what size piston/rings and rod to get- the new parts will need to go to the machine shop before any actual machining work is done. The old valves should be able to be re-ground.

-Mark-

[E12Horse 2]

Ok, the parts are at the machine shop. He can save the crankshaft by grinding down .010. He will re-bore by.020.

The valves can be ground and re-seated. All for $315

Now I need parts. A local Napa store can do Piston, Rings, Connecting Rod and Seals for $178.

I found Petessmall engines online with Stens aftermarket parts for $102

Any advice on saving money with an online purchase versus considerably more for Napa parts?

[tunahead72 2,551]

My local NAPA dealer sells both genuine Kohler and aftermarket parts, which are you getting for $178?

Do you have a local Toro dealer, or probably more likely, a Kohler dealer? They might be more competitive than you would think.

Likewise, there's lots of online suppliers, some of which carry both Kohler and aftermarket parts -- have you seen the list here on RedSquare?

I'm not really qualified to give you advice on Kohler vs. aftermarket. I tend to prefer Kohler when I buy, but others here use aftermarket parts with very good results. I'm really just trying to advise you to shop around, and know what you're getting.

Good luck!

[MarkPalmer 81]

Always check E-Bay. There are a lot of people there who sell new-old-stock Kohler parts at substantial discounts. Also look on Brian Miller's site (gardentractorpullingtips) as he sells new and reconditioned parts at good prices too. There are several parts dealers on this site too. I would at the very least get a genuine Kohler piston and rod. The machine work price sounds reasonable for what is being done.

-Mark-