Valve Guide Clearance & Replacement Tools ?

[oliver2-44 8,836]

I have a couple of engines I need to overhaul and I'm interested in how others check the valve guide clearance.  In my limited experience it a shame to do an Overhaul and still have an engine smoke due to the guides being worn.

Does anyone use a set of Ball Gauges like these?   These cost a whole lot less than the name brand ones, but seem they would do the job, or is there a better way. https://www.ezbore.net/Ball-Gauge-Set-p/nog2601.htm

 

Also what do you use to pull old guides and install new ones.  The Kohler overhaul book show a partial picture  of a valve guide puller being used, that is a special Kohler tool.  I'd be interested in any pictures of what you use.  I can see how some all thread and a "special piece" just less than the OD of the guide could be rigged up as a pulled. But then how do you install the new ones?  

[classiccat 548]

I've never done a Kohler but have done an old Briggs last summer using this kit (5/16" valve stems).   Maybe a similar kit exists for Kohler? 

 

 

 

 

[new2horses 287]

JIm,

 Years ago when I was doing several of the K series engines each year, the owner of my local Kohler engine shop, told me that he had never found it necessary to replace the valve guides on an engine. I followed his advice and have never changed the valve guides on one of the K series engines. Not having changed the valve guides has never caused any issues. I have however on numerous occasions the valves.

That said if you are still determined to change them then drill and tap the guide and using a suitable spacer pull them out.

Let the discussion begin.

David

[953 nut 51,527]

Here is information from Brian Miller's site.

Questions:

1 - I've seen there's a special tool for removing the valve guides. Do I need it or is there a DIY trick?

2 - What's the best way to clean what I believe is the valve seats - where the valves sit in the block? In the attached photos you can see my exhaust valve seat(?) isn't too bad, but the intake one is a bit more crusty.

3 - Would I be going too far overboard by getting all new valve components?

Here is a good read for you.

http://gardentractorpullingtips.com/valvecam.htm

There are two ways to measure the amount of wear in valve guides. One way is with a dial indicator. The other way is with an "go/no go gauge" and a micrometer. It's best to have a local machine shop do the measuring because they have the right tools and they're experienced with such things.

How to Remove and Install Pressed-In Cast Iron Valve Guides in a Cast Iron Block Kohler Engine:

1. Acquire a 1/2" diameter x 5" long grade 8 bolt. Machine the threads down to .300" so it will become a pilot to fit inside the valve guide. This will be the driver tool.
2. Remove the valves, springs and retainers. Measure old guides to ensure if they are actually worn or within specs.
3. To remove worn valve guides:
   • On the Kohler engine models K141, K160/K161 and K181/M8 and all flathead twin cylinder Kohler engines, if the lifters (and camshaft) are installed, break off half of the guide inside the valve spring compartment with a cold chisel and medium size hammer, then use the machined bolt as mentioned above È and a big hammer to drive the remaining guide out and into the valve spring compartment. If the lifters and cam isn't installed, just drive the entire guide out into the valve spring compartment without breaking it off.
   • On the Kohler engine models K241-K341, if the lifters (and camshaft) are not installed, drive the entire guide out into the valve spring compartment with the machined bolt and a big hammer. But if the lifters (and camshaft) are installed, and if there's not enough space to remove the entire old guide, then half of the guide will need to be broke off with a cold chisel and hammer, then the rest of the guide can be removed.
4. Install the new guide with the machined bolt with a flat washer under the pilot so the guide will be flush inside the intake and exhaust pockets.
5. The new guides may need to be reamed out with a 5/16" reamer so the valve stems will have correct clearance.

FYI - In most cases, worn valve guides don't necessarily need to be replaced. They can be repaired with a thin-wall bronze sleeve/liner, like the ones installed in automotive cylinder heads. Also, a bronze liner will last longer than a cast iron guide because bronze retains more oil for better lubrication for the valve stem.