Con rod wear pattern ok?

[953 nut 51,675]

17 hours ago, squonk said:

Get some green plastigage and check it. Cheap insurance.

I agree with others on the suggestion to use plastigage to check clearance (.001 to .002) of the rod to crank. As for the dark areas of the rod not contacting the crank I suspect that has been that way for the entire life of the engine. I see no way that unusual wear could occur leaving that type of signature. The majority of the rod is making contact and those dark areas are near the edge probably allowing more oil to splash into the clearance between the rod and crank. The rod and crank look smooth and have no evidence of uncharacteristic wear pattern so they should be fine.

[squonk 38,920]

So If you weren't planning on changing the rings and honing it, Why did you even take it apart? 

[ebinmaine 63,130]

5 minutes ago, squonk said:

So If you weren't planning on changing the rings and honing it, Why did you even take it apart? 

Originally to check the balance gears which were loose so I'm REALLY glad I took them out.

 

While I was in there I figured I would pop the rod cap off just to see how the inside of that looked.

 

 

[squonk 38,920]

If the gears were loose the engine is loose too. I had small amount of wobble in my K341 gears and when it was torn down the crank and bore were out of round, piston skirt was broken and the guides were shot. You engine may run forever, but don't be surprised if it doesn't. Hate to see another 16 get ruined.

[WHX?? 46,770]

Great Dan ... now if I could just count my toes and get the same number twice. 

[WHX?? 46,770]

26 minutes ago, squonk said:

crank and bore were out of round, piston skirt was broken and the guides were shot. You engine may run forever, but don't be surprised if it doesn't. Hate to see another 16 get ruined.

Yah but EB plans to run OIL in his...

[SylvanLakeWH 24,130]

1 minute ago, WHX?? said:

Great Dan ... now if I could just count my toes and get the same number twice. 

I do that before and after every mow... so far so good... 

[ebinmaine 63,130]

13 minutes ago, squonk said:

If the gears were loose the engine is loose too. 

 

. Hate to see another 16 get ruined.

 

No worries Mike.

 

 

Somebody's standard bore rebuilt this one in the past. 

It has a newer piston, rings, rod, and the cross hatch is still very evident in a lot of the cylinder bore.

 

My experience shows most people don't touch the balance gears.

 

I checked with the two local small engine repair shops I would normally deal with and neither one of them has ever changed the balance gear set.

That's not a huge surprise for one of the places because the guy is only about 30 or 35 years old... but the other place has been in business 30 or 40 years. One of the technicians used to work at a Toro dealer and both of the guys there used to handle these Kohler singles on a very regular basis. I was quite surprised when they told me they hadn't handled them but I guess when you think about it they're 30 years old at the newest now so they're sort of off the radar screen as usable machines to most folks.

 

 

Believe me when I tell you I feel the same as most of the folks on this site about keeping this old iron alive. If I wasn't reasonably confident that this engine was going to last a few more years I wouldn't put it together as a runner.

I have two other Kohler 16 HP  engines that I know are loose and I also know they run. 

 

I won't use either one of them until they're bored over and rebuilt with new parts. 

.

[John2189 406]

14 minutes ago, SylvanLakeWH said:

I do that before and after every mow... so far so good... 

every time I use my table or radial arm saw, I always look at my hands to make sure I didn’t cut a finger off. 🙂

[squonk 38,920]

28 minutes ago, WHX?? said:

Yah but EB plans to run OIL in his...

Funny. Considering my engine was still running in this condition on Rotella 30W

 

 

 

[ebinmaine 63,130]

10 hours ago, Achto said:

 

Some thing to add to your arsenal one day. Maybe not the best quality sets if you are a machinist, but they will be good enough to let you know what's going on & what you need for parts.

 

https://www.harborfreight.com/search?q=telescoping bore gauge

 

https://www.vevor.com/outside-micrometers-c_10820/vevor-outside-micrometer-premium-precision-carbide-tips-machinist-tool-0-4--p_010689764898?utm_source=google&utm_campaign=18457895227&utm_term=&gclid=EAIaIQobChMI1OuP8bG6_AIVhxfUAR0I8gmzEAQYBSABEgLkV_D_BwE&v_tag=7ec532d0-9011-11ed-ac31-9daacb9ce42b.1

Thanks for the links. 

 

I have a set of mics. Might have to get a set of bore gauges.... 

[WHX?? 46,770]

I got a set in the jungle for the about the same price and right to my door. Good enough for the hobbyist... Now just to figure out how to use them!

[pacer 3,159]

44 minutes ago, WHX?? said:

how to use them!

 

Pretty simple, select the proper size ( (the 'E' will cover most of out stuff) slip it into the cyl at a slight angle and gently move it til its straight across and gently tighten it, pull it out with it locked in that setting and use the mic to measure that. I generally do 4-5 readings in different areas of the bore.

 

The reading in the pic was in a K241, notice the reading is at dead straight across at 3.25 which is factory bore and the other is the crank measuring at 1.49 wear (std is 1.50) -- That was a remarkable little engine for that little wear!

 

 

Edited January 9, 2023 by pacer

[SylvanLakeWH 24,130]

Well... I know they spell like your typical Cheese head so... 

 

 

 

 

[ebinmaine 63,130]

13 minutes ago, pacer said:

generally do 4-5 readings in different areas of the bore.

Fella I knew many moons ago used to do 6 measurements.  

1. Top.   Just below the ring ridge (if there was one). 

2. Middle of the ring set travel.  

3. Just above the bottom of the bore.  

 

All those were with, and 90⁰ from, crank travel direction.  

 

 

[pacer 3,159]

Eric, guys, I forgot to mention the cranks odd markings (what I initially started the post for) I scratched my head quite a bit on that and could never really get an answer. When I first opened it up, I thought the crank was bad, but I measured and ckd everything I could think of with no real answer, so, with those readings I put it back together with a new set of rings/gaskets. 

[953 nut 51,675]

9 hours ago, ebinmaine said:

 

I checked with the two local small engine repair shops I would normally deal with and neither one of them has ever changed the balance gear set

They just waited until the grenade gears popped a hole in the block and then sold the unsuspecting customer a long-block replacement engine.

[ebinmaine 63,130]

6 minutes ago, 953 nut said:

They just waited until the grenade gears popped a hole in the block and then sold the unsuspecting customer a long-block replacement engine.

 

The newer guy might...

 

The older shop I mentioned would NOT do that.  

They're one of the few remaining  REPAIR SHOPS  In the area.  

 

[WHX?? 46,770]

1 hour ago, pacer said:

and use the mic to measure that.

Thanks Pacer... I was using calipers not a mic ... it that my down fall? 

I tried measuring some Onan bores like this and wrote down all the numbers. Gave the block to @Achto and he measured it ovaled which i did not see. I trust Dan more than my toes so the block went on the shelf. 

I was ok at algebra but 1+1 aways = 3...

Edited January 10, 2023 by WHX??

[lynnmor 6,777]

1 hour ago, WHX?? said:

I got a set in the jungle for the about the same price and right to my door. Good enough for the hobbyist... Now just to figure out how to use them!

The way I was taught to use them 59 years ago is as follows:

Choose the appropriate size.

Put a drop of oil on each contact area.

Insert the gage in the bore and have it at a slight angle.

Slightly tighten the clamping screw., it too should have a drop of oil on the inside end.

Rock the gage over center one time so that it compresses to bore size.

Continued rocking can only collapse it too far.

Mike the gage to find the highest reading, being mindful of the not so tight screw.

Lather, Rinse, Repeat till you get consistent readings.

 

Trying to find the exact perpendicular contact points by eye ain’t gonna happen.

Always store the gages at their largest position so the spring isn’t collapsed.

 

This just in, calipers have no place in engine work.

Edited January 10, 2023 by lynnmor

[WHX?? 46,770]

7 minutes ago, lynnmor said:

This just in, calipers have no place in engine work.

Whats the theory behind this?   Guess I'll be following Dan's link.. 

Like @953 nut always says let the shop tell you but always nice to know what yer up against.  

[lynnmor 6,777]

You cannot get accurate measurements with calipers.  Many will tell you otherwise, and I have worked with those and seen their work.  When measuring a bore, there is no way to get a reading down in where it matters.  The contact points of a caliper are flat, how would you measure with flat surfaces contacting round surfaces?  To me, a caliper is a quick check device to get a rough measurement.

[ebinmaine 63,130]

13 minutes ago, lynnmor said:

To me, a caliper is a quick check device to get a rough measurement.

Pretty much what I was always told.   

[WHX?? 46,770]

20 minutes ago, lynnmor said:

a caliper is a quick check device to get a rough measurement.

Exactly what I would/was aiming for ... let the machine shop figure out the details. 

[lynnmor 6,777]

32 minutes ago, WHX?? said:

Exactly what I would/was aiming for ... let the machine shop figure out the details. 

Now what are you going to do when the machine shop whips out his cheap calipers?  I made my living in machining and have seen a considerable number of folks that aren’t qualified.