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Valve lapping tool

Discussion in 'Tool Corner' started by Willy Eckerslyke, Apr 16, 2018.

  1. Willy Eckerslyke

    Willy Eckerslyke Well-Known Member

    'Morning all,
    Just wondered if anyone can recommend a valve lapping tool? I need to grind in the valves of a P4 6 cylinder engine that needs a decoke and a couple of exhaust valves replacing. The thought of doing them all with the usual stick & suckers doesn't appeal much.
    Is the Gunson Eezilap any good or do you have a better suggestion?
    Gunson G4095 Eezi-lap Valve Lapper - Machine Mart - Machine Mart

    As this is an inlet over exhaust engine, the exhaust valves are in the block so taking them to a machine shop isn't an option (without taking the engine out). And there isn't access for a trick like connecting a drill to the valve stem with a rubber hose.
    Any recommendations appreciated.

    (And if anyone has a spare exhaust valve for a 1954 2103cc engine, I could use another. Also a few head bolts...)
     
  2. cobraboy

    cobraboy Well-Known Member

    Sucker stick in a cordless drill does it for me.
     
  3. Willy Eckerslyke

    Willy Eckerslyke Well-Known Member

    That does sound like a cheap and simple solution. Is there any risk with running it for too long in one direction?
     
  4. cobraboy

    cobraboy Well-Known Member

    Not if you take your finger off the trigger :)

    Seriously - if they are bad start off with coarse paste, then move to fine. If you put a little paste on the face then use the drill to turn the stick it will sound gratey at first, then will smooth out. Lift the valve off the seat and tap it down again a couple of times, it will grate again as the new paste gets to work.
    When you have a nice even grey ring all the way round switch to fine to finish.
    Take great care not to get paste on the valve stem, which should be lubed with clean oil.
    You don't need to reverse direction, you are only cutting an even seat, it does not matter which way it runs.
    Make sure that no paste is left on the seat or valve when you finish.

    Retire to the pub for beer and medals.
     
    Willy Eckerslyke and So Cal V8 like this.
  5. cobraboy

    cobraboy Well-Known Member

    Of course if you have access there is no reason why you cannot put the valve in the head and then put the collet end in the drill chuck and dispense with sucker stick altogether.
    Australians probably do it this way, I always use the stick.
     
  6. Willy Eckerslyke

    Willy Eckerslyke Well-Known Member

    Thanks, I'll be able to attack it with confidence now. My biggest worry is keeping grinding paste from dripping into the guides due to the orientation but I'm hoping I can slip on a rubber tap washer or something to help prevent that.
    Also, I'm dreading replacing the collets "up hill" rather than just dropping them in as normal. No doubt there's a trick to it that I'll figure out on the last set.

    No access to the the collet end on the exhaust valves as they're not in the head, but it would work on the inlet valves.
     
  7. colnerov

    colnerov Well-Known Member

    Hi, It's been a while since I've worked on the IoE engines and I had the same concerns, the grinding paste tends to get moved outwards so away from the guide. To avoid losing the collets I stuffed the gallery with paper or cloth wipes to stop anything falling further into the engine and use a dab of grease so the collets stayed where they were put. When the grinding is finished you can wash the port out with petrol and a brush and if any petrol goes down the guide the cloth or paper will soak it up.

    Colin
     
  8. Willy Eckerslyke

    Willy Eckerslyke Well-Known Member

    Thanks Colin, using grease to hold the collets in sounds a great tip. As does washing the port with petrol (though I prefer the smell of white spirit).
    I did stuff the gallery with cloth when removing them so will make sure to do the same when replacing the collets.
     
  9. ButterFingers

    ButterFingers Active Member

    hi there, you would be surprised what Australians do on there heads............look at the world upside down...surf with sharks...do a bush bash in a rover 90 , no back up and still finish the course...but as
    for valves and collets, we throw away the rule book....go for gold..
    Peter the impossible
     
  10. Dave3066

    Dave3066 Active Member

    I have one of those lapping doodahs Willy and they're fine for a short period of time. Too much usage and they destroy themselves. It's all plastic inside and the build up of heat from what I would regard as normal usage causes the internals to distort to the point where it becomes scrap. Stick with the stick :) or go for the Oz method as described above.

    Dave
     
    Willy Eckerslyke likes this.
  11. Willy Eckerslyke

    Willy Eckerslyke Well-Known Member

    Thanks Dave, thirty quid saved!
     
  12. cobraboy

    cobraboy Well-Known Member

    Uh huh

    Trouble is bush bashing means a whole different thing over 'ere ;)
     
  13. unstable load

    unstable load Well-Known Member

    What he says!!
    Specifically the last sentence..:D
     
  14. ButterFingers

    ButterFingers Active Member

    so what does "bush bashing" mean in your neck of the woods? :rolleyes:
    Peter
     
  15. cobraboy

    cobraboy Well-Known Member

    Peter
    If I have to explain it I will be barred, black balled or have some other nasty penalty, use your imagination...........................


    .............Hey, its what you outbackers do when you hit town after 6 months on a sheep station :cool:
     
  16. ButterFingers

    ButterFingers Active Member

    Over here it is usually a charity sponsored drive to raise money, all types of vehicles are used, mostly old ones, with garish paint jobs and various attachments to draw attention .
    Starting in Sydney,NSW, and ending in say Cairns in the north of Australia.
    A friend of mine did a "bush-bash" about 25 years ago in a Rover 90, They just bought the car for about $100, fitted knobbly tyres , because many of the miles would be on dirt, and off they set.
    other contestants had works prepared cars, many thousands spent, a full backup crew and car and many did not even finish.
    Says something for the reliability of a Rover of the day.............

    I get the Gist of your "bush-bash" by the way....tut tut:p
    Peter
     
    Last edited: Apr 21, 2018 at 1:33 AM
  17. classicalgreen

    classicalgreen Active Member

    not sure I read that correctly but seem to get impression folk are just using a drill to spin valves. the lapping in with paste!
    correct way ( according to my training at a major motor company laboratory ) is to apply small amount of coarse paste . using stick with rubber on valve press gently down and rotate back and forth a few times .like a Boy Scout using a stick to start afire! then lift stick every 3-4 twists and rotate 120-180 degrees and. do same. after every grind session before dropping down for next lapping ...smear paste again with finger ( not add more) .
    when grey area. is seen to be approaching a reasonable width and All around circle of vale seat. removes clean and then use medium paste. repeat . then again last time with fine paste .
    we ought to end up with a nice clean grey contact area .bear in mind. its best. not to exceed widths recommended for the valves. inlet and exhaust will have a different width of contact ( grey area) .
    important to clean off all paste.
     
  18. ButterFingers

    ButterFingers Active Member

    That is the way that I learnt to do it, many years ago, the correct way incidentally as tought in the local techs over here.
    using a drill and applying pressure is a sure fire way the grind off too much all in a few seconds, what comes off cannot be put back, a bit like cutting a piece of timber too short at one end ! :rolleyes:
    Peter
     
  19. ButterFingers

    ButterFingers Active Member

  20. classicalgreen

    classicalgreen Active Member

    should have added reason for regularly re-smearing paste is to prevent tram lining . thats where grit in rotating action binds and creates grooves . not good! you want smooth contact areas with no tramlines. inlets need wider 'grey area' than exhausts and its not advised to over grind and have grey contact areas go from full width of valve. contact face edges. small area no contact is best on each side of our grey lapped section.. not many aware that valves when working do actually rotate in cylinder head and also the poppet ( valve end ) section also deforms and bends with heat and pressure . this is a normal function and the special steels and manufacturing process take all that into consideration. one can also check valve sealing with fluid checks ( both closed) by filling with fluid and leaving for an hour .no fluid ought to seep past our now perfectly sealed valve seats. engineering works use pressure testing a star quicker.
     

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