CHECK VALVE-TO-TAPPET CLEARANCE

[Retired Wrencher 5,656]

Looking  for the gap Tappet clearance. on K181. Thanks in advance.

[pfrederi 18,366]

3 minutes ago, Retierd Wrencher said:

Looking  for the gap Tappet clearance. on K181. Thanks in advance.

.006/.008    .017/.019

 

from the manual

 

[Maxwell-8 4,366]

Somthing I never real have understand is how do you adjust that clearance.

If you have to little, you grind a bit off, but what if you have to much clearance?

 

[Gregor 4,847]

18 minutes ago, Maxwell-8 said:

but what if you have to much clearance?

You buy a new valve.

[Gregor 4,847]

Depending on how much you need, you can also grind the valve seat, and/or valve face.

[moe1965 752]

If you grind your own stem go easy and use a fine wheel. It easy to take to much  at one time check clearance often 

[Retired Wrencher 5,656]

2 hours ago, moe1965 said:

If you grind your own stem go easy and use a fine wheel. It easy to take to much  at one time check clearance often 

That is my concern. I will have to see what I have for wheels.  .006/.008    .017/.019 is an easy to go over. Just wish these had a just nut. A lot easier.

[Jeff-C175 7,203]

11 hours ago, Maxwell-8 said:

what if you have to much clearance?

 

Which I don't think is that often seen, and is probably most likely the result of an over-agressive grinding of the stem.

 

If you consider the way a valve wears, typically the seat and valve face will wear faster than the stem / tappet / camshaft lobe , and this would cause the clearance to get tighter.

[RED-Z06 2,481]

If you have too much clearance you have to cut the seat, you use a fixture that is inserted into the valve guide and a cutting head is lowered down and manually rotated to make a cut...you make a few turns then recheck lash, face the valve and lap it in...this is a pain in the rear ans time consuming 

[rjg854 11,915]

When @squonk and I was rebuilding an eight horse for me, we got new valves and one of the valves was too short to begin with. Had to grind some of the face of the valve off in order to get the right gap.

[pfrederi 18,366]

5 hours ago, moe1965 said:

If you grind your own stem go easy and use a fine wheel. It easy to take to much  at one time check clearance often 

 

I have a KT 17 with a nice tick got a bit carried away with the grinder...

[lynnmor 7,595]

A surface grinder is the proper tool to grind the valve stem ends.  Trying to do them by hand is only guessing and the end will not be square to the stem.  There are specialized grinders for the purpose.  Any good engine shop or machine shop can grind the exact amount in minutes.

[Wheelhorse#1 1,767]

1 hour ago, rjg854 said:

When @squonk and I was rebuilding an eight horse for me, we got new valves and one of the valves was too short to begin with. Had to grind some of the face of the valve off in order to get the right gap.

Was wondering.Did you go with China after market valves?Seems odd not being in spec out of the box.

[Gregor 4,847]

15 minutes ago, lynnmor said:

Trying to do them by hand is only guessing and the end will not be square to the stem.  There are specialized grinders for the purpose.

Grinding valve stems is a slow tedious job. Not one of my favorites, when rebuilding an engine, I always worried about having the end of the stem square to the valve. While this set up I'm sure is not 100% accurate, it has to be better than holding your valve stem to the side of your bench grinder, and hoping for the best. Once I am in spec, I change out the grinding wheel for a sanding disc, to polish the end a bit more.There is a small brass plug between the valve stem and the thumb screw. Prevents damage to the stem.

I can set my dial indicator up to see just how much I have taken off.

It isn't a job you want to do twice. Besides, who has an extra valve laying around?  Oh yeah, I do.

[rjg854 11,915]

45 minutes ago, Wheelhorse#1 said:

Was wondering.Did you go with China after market valves?Seems odd not being in spec out of the box.

I think Mike said he got them from I save tractors

[Wheelhorse#1 1,767]

39 minutes ago, rjg854 said:

I think Mike said he got them from I save tractors

 I believe they sell 🇨🇳 aftermarket parts.I’m not saying it’s a bad company or anything,it happens I’m sure.

Edited January 5, 2022 by Wheelhorse#1

[Gregor 4,847]

1 hour ago, Wheelhorse#1 said:

Was wondering.Did you go with China after market valves?Seems odd not being in spec out of the box.

A manufacturer cannot produce a valve in spec for your motor. All motors have worn differently. Tappets, rocker arms, valve seats, cams, and whatever. My

[squonk 42,718]

I use a Horror Fright belt sander with #400 & 600 paper. I made a wooden jig the stem fits into to keep it square.

 

Edited January 5, 2022 by squonk

[Handy Don 13,375]

3 hours ago, Gregor said:

While this set up I'm sure is not 100% accurate

I really like the setup, but am especially intrigued by the vise. Very handy to have the angle setting option. 

[Jeff-C175 7,203]

2 hours ago, squonk said:

a wooden jig

 

Think I would use a V block for that myself.

 

[Retired Wrencher 5,656]

I guess when I get it a part, I can shoot a video of what the clearance is. Just doing research now.

[Retired Wrencher 5,656]

10 hours ago, squonk said:

I use a Horror Fright belt sander with #400 & 600 paper. I made a wooden jig the stem fits into to keep it square.

 

Mike can you put a picture up of the jig? Just waying my options now. And what did that cost?

[Retired Wrencher 5,656]

Thanks for all the info. Just looking at my options for later in the year on this. Still working on the commando.

[squonk 42,718]

8 hours ago, Jeff-C175 said:

 

Think I would use a V block for that myself.

 

I use the belt. V block wouldn't work.

[squonk 42,718]

34 minutes ago, Retierd Wrencher said:

Mike can you put a picture up of the jig? Just waying my options now. And what did that cost?

It's just a square block. I squared up the fence on the sander. Squared 3/8" hole in the block. Valve is inserted in to the block and block rests against against the fence. I use light pressure and twirl the valve head. Then check it with a metal square. Sander is currently 90 bucks.