Major overhaul of K301

[lynnmor 6,796]

3 hours ago, tom2p said:

back in the day - we used STP as a pre-lube ... on rod and crank bearings ... cam and lifters 

 

not sure if it was the best thing to use - but that's all we knew at the time 

some used a light film of oil on the cylinder bores - others preferred dry (?)

 

the other thing I recall :  after cylinder was bored and / or honed - we washed in hot water with dishwashing detergent (Dawn ?)

 

 

I did the same, except the STP was mixed with motor oil 50-50.  At least we didn't start them up dry and wait for the oil to circulate.  The cylinder walls can hold swarf from boring and honing, so a good wash down is in order, I use the hot water dish soap on small engines, on a large engine I used a solvent.

[Greentored 3,201]

Anxiously awaiting your block to come back and see this going together!

 

Heres a couple tricks for you guys:  50/50 ATF/WD40 on the cylinder walls for assembly. Wipe the cylinder down good with this and a rag, you'll be amazed at how much 'trash' you'll have on your rag. Do this til its clean, then slather it on the cylinder and stab the piston home. Theres just enough lube to prevent a dry start, but not enough for the rings to 'ride' on top of. You'll have near instant ring seating....well....on anything but those chrome rings. Those are gonna take awhile ha......

Another trick for rings- they can be confusing. Oil rings can go either direction. Top rings often can as well- if theres no dot and no visible taper on the inside edge, you're usually safe to install either way.  The second ring is a scraper- to be 100% sure every time when in doubt- install it on the piston, install the piston upside down with rod attached, run it up and down the bore a dozen times and remove. You'll see a very thin, shiny line on the ring- that line goes down. Of all the rings, this is the one you don't want to screw up, or you'll have a mean oil burner!

As for staggering the rings- make sure your 3 piece oil ring gaps are all staggered, and make sure your top two are as well and send it home. Stagger between oil rings and top two dont matter.

[Mickwhitt 4,155]

Engine back home from the machine shop.

[tunahead72 2,343]

Oh, that's pretty! 

 

[Tuneup 1,416]

When you said 'bore', you meant it. I would have put a bit of steel wool buffing on the deck to make it shiny for you!

[Mickwhitt 4,155]

Washed out the bore with soap and water, dried and oiled it as per your instructions. 

Lapped in the valves and cleaned the grinding paste off scrupulously. 

Fitted the cam shaft, checking end float. Knocked in an expansion plug which was missing when I stripped the engine but should be there to seal the camshaft pin.

 

 

 

[WHX?? 46,809]

Don't forget the cam shim Mick & don't ask me how I know! 

Edited February 17, 2021 by WHX24

[Mickwhitt 4,155]

2 shims in mine and end float within limits. 

Crankshaft fitted, timed up with the cam shaft.

Bearing plate fitted and end float of the crankshaft checked and within limits. 

I made a pair of lining up pins to hold the gaskets and shims in place while I knocked the bearing plate on.

 

 

[Bill D 1,602]

Have you considered having the crankshaft balanced before final assembly?  David Kirk sells a balance plate that you can install yourself if needed.  Any thought @Greentored?  Bill

[Mickwhitt 4,155]

The crank was reground so I'm hoping it will be in balance still.

Not much I can do about it now lol.

Bottom end is all back together and done.

 

Valves ready to be fitted in the morning and I will see where that gets me in relation to finishing off the rebuild.

Mick 

 

[Greentored 3,201]

13 hours ago, Bill D said:

Have you considered having the crankshaft balanced before final assembly?  David Kirk sells a balance plate that you can install yourself if needed.  Any thought @Greentored?  Bill

It definitely helps, but not completely necessary unless you made major changes to the weight of internal parts. Regrinding the crank wont change anything enough to worry about.

On a good note- these things want more counterweight, and less piston/rod weight is the same thing- that means if regrinding the crank DID make a difference, you're going in the right direction. Also- have seen some aftermarket pistons with a thin wall wrist pin versus the heavy beast OEM one. Again, going in the right direction- less weight there equals more on the counterweight

[Greentored 3,201]

Looks great, but you forgot a couple steps! 

[Mickwhitt 4,155]

Lol, im hoping im not missing any steps out!

I put the engine back in the frame today so I can lose the lift table and there was less weight to hump about getting it sat on the shaker plate.

Valves are in and gapped, breather assembly refitted, fuel pump and cam gear cover on.

Now the steady rebuilding into the frame and harness. 

All is looking good. But didn't they say that on apollo 13 lol.

Mick 

 

 

[Mickwhitt 4,155]

Engine just about rebuilt, only the carb to fit and she is ready to start up tomorrow.  

Did the static timing but the generic points are pretty poor and needed some modifications to get them to gap at 30 thou. Hopefully they will be OK but if not I will clean up the Kohler ones.

Mick 

[ebinmaine 63,203]

23 minutes ago, Mickwhitt said:

30 thou

That the right spec?

 

20?

 

[richmondred01 2,208]

Yep .020 to start with.

I’m not sure what points you have but I don’t recommend generic ones. Get the Kohler, Steins or Napa brand. 
I’ve seen the generic one melt and/or short on several occasions. 
 

Edited February 20, 2021 by richmondred01

[Gregor 4,838]

As someone who has been there. You DON"T want to fight a bad set of points right off the git go !

[Mickwhitt 4,155]

Don't know why I typed 30 thou, fingers like cows teats lol.

 

Finished off the carb and other bits this morning and it was time for the moment of truth.

 

Got everything set and double checked....

Looks like I'm not as stupid as my wife thinks I am lol.

 

Mick 

[richmondred01 2,208]

Sounds and looks great.

Congratulations.

job well done. 

[Mickwhitt 4,155]

Thank you.  I would never and I mean NEVER  have attempted this without the support of the fine fellows on Red Square. 

Every step of the way was paved with the advice of experienced and skilled people good enough to lend their time to some ne'er do well in England.

You gave me the confidence to take on what is quite a major project for a back street mechanic like me.

My grandfather taught me the basics of engine repair when I was perhaps five or six years old.

My hands would fit where his huge paws would not so I became his apprentice.

I hope he is looking down on me and thinking he didn't do too bad a job after all. 

Mick 

[ebinmaine 63,203]

Fine work sir. 

Absolutely. 

[Slightly Discombobulated 6]

Sounds great and looks great Mick! Looks like it's ready for 40 more years. 

[Greentored 3,201]

Awesome job bud!!!

[Gregor 4,838]

@MickwhittIf possible, I would like to see some pics of your governor and throttle connection on your K161. I believe mine is missing some bits, and I would like to know just how it is suppose to be hooked up.  Thanks  Greg

[Mickwhitt 4,155]

Hi Greg.  No problem.  I have photos and will upload  few asap to show the governor and throttle linkage.

Mick