Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

  • Announcements

    • Kent

      Sign In or Password Problems?   10/09/2016

      If you can't Sign In, you need to reset your password.  Use the Forgot Your Password link at the bottom of the Sign In screen, and the site will send you an email to reset it. If you have an AOL email account, use the Contact Us link at the bottom of the screen -- AOL is intermittently blocking email from the site.
    • Kent

      Feedback Please!   10/28/2017

      See News and Announcements forum.
Sign in to follow this  
alec

lapping and grinding valves

Recommended Posts

Kenh

Somebody makes a suction cup valve twirler. Here is one. I think a couple different sizes are available. http://www.tooltopia.com/lisle-21100.aspx?utm_source=google&utm_medium=cpc&utm_campaign=paid_search_google_pla&scid=scplp6819518&gclid=CLT2jfCh6MUCFQqGaQodFIcAAQ

Here is a video of a guy using a drill. This is what I do as it is much quicker.

You'll need some lapping compound.

http://www.autozone.com/miscellaneous-cleaners-and-degreasers/valve-grinding-compound

CLEAN, CLEAN, CLEAN after using the compound so as not to introduce any into the engine after the rebuild. Don't ask how I know!:I:D That was my first job and the last one that had an "issue".

Ken

Share this post


Link to post
Share on other sites
BLT

I get the valves done and then lap them and if the valve seat and valve have a pencil width mark or so with the mark on the valve less then half way out, don't mess with it. You'll get a couple thousandths less stem gap but has never given me a problem.

Share this post


Link to post
Share on other sites
alec
quote:Originally posted by Kenh

Somebody makes a suction cup valve twirler. Here is one. I think a couple different sizes are available. http://www.tooltopia.com/lisle-21100.aspx?utm_source=google&utm_medium=cpc&utm_campaign=paid_search_google_pla&scid=scplp6819518&gclid=CLT2jfCh6MUCFQqGaQodFIcAAQHere is a video of a guy using a drill. This is what I do as it is much quicker.https://www.youtube.com/watch?v=TrKINFBsQD8You'll need some lapping compound. http://www.autozone.com/miscellaneous-cleaners-and-degreasers/valve-grinding-compoundCLEAN, CLEAN, CLEAN after using the compound so as not to introduce any into the engine after the rebuild. Don't ask how I know!:I:D That was my first job and the last one that had an "issue".Ken


id="quote">
id="quote">how would I use the drill on the briggs ? seems like the angle would be an issue . could a guy modify the hand held one and put it in a drill ?

Share this post


Link to post
Share on other sites
alec
quote:Originally posted by oldsarge

wahplease don't just lap the valves.Cut or grind the valves and seats first.Just a couple of twirls with the cup and you'll have a REAL valve job!


id="quote">
id="quote">could you tell me more about this cup ? I am all ears ... and brave ... and willing to learn . I am really enjoying this hobbie and its mostly because of you guys here ( and gttalk )

Share this post


Link to post
Share on other sites
TimJr

One of the lessons I was taught about valves is this. If the valve and seat are new or have been machined with a stone grinder, then lapping is only done to "finish it off". Use the lightest grit, and only do a couple of light spins between the valve and the seat to show the contact between the two, but not to actually "grind" into or remove material.

If the valve and seat are used, and are not going to be actually machined, lapping in can improve a worn or pitted valve. Not the best way to go about it, but can get you by. The wider the contact between the valve and the seat, the more likely it is for carbon to build up there and cause a leaky valve. There are specific measurements for this in an engine manual.

If the valve or seat are being "cut" - as in using a Neway carbide cutter set, then lapping is necessary as far as I am concerned. The carbide cutters are great, but can "chatter" and leave a bumpy or uneven surface compared to valve ground with a stone. The lapping will help to wear down the bumps and leave a smooth sealing surface.

I have done both - ground with a stone, and used a Neway cutter. The stone leaves a much nicer finish. The Neway is fairly quick and easier to set up. Nothing like a good 3 angle valve job on a Briggs!

If you are new to this, and have access to the tools, see if you can find a junk engine or automotive cylinder head to use as practice. If you wreck a seat on the engine you are trying to save, it could really cost you depending on what it is. Have fun learning, Tim

Share this post


Link to post
Share on other sites
alec
quote:Originally posted by TimJr

Nothing like a good 3 angle valve job on a Briggs!

If you are new to this, and have access to the tools, see if you can find a junk engine or automotive cylinder head to use as practice. If you wreck a seat on the engine you are trying to save, it could really cost you depending on what it is. Have fun learning, Tim


id="quote">
id="quote">

what do you think about this grinder ?

http://www.jackssmallengines.com/Products/Universal/Small-Engine-Tools/Valve-Grinder/750208/57791/s

Share this post


Link to post
Share on other sites
TimJr

Looks like a carbide cutter? I have not used one like that. It definitely is the cheapest cutter I have ever seen.

Having valves and seats ground by a shop are usually pretty cheap - especially compared to buying good tools to do it yourself. If you only are doing one or two engines every now and then, a Neway kit or stone grinder kit just can't be justified unless you have money to burn and just want them. Tim

Share this post


Link to post
Share on other sites
briggsetc

That is the old school reciprocating tool with suction cups. They have been making those tools since the at least the 1920s. I have a couple I bought at auctions but never had them work good and always went back to the tried and true wood stick with suction cups. Napa shows 2 versions of the wood cup tool for under 5.00 each. Part no SER 501 and SER 505.

Gary

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this  

×