valve grinding 4 engines

                                              THINGS TO CONSIDER FIRST        DO YOU KNOW WHERE ALL THE TIMING MARKS ARE
       DOES YOUR MOTOR HAVE A GAS TYPE CHAIN /BELT TENSIONER?
       Does your head have adjustable valves  
       Does your head or motor have hydrolic tappets"?
       Can you afford a Head Gasket set if so how much can you spend ?
       Are you using a used replacement head is it rusty ?
       Have you ever worked on cars motors or lawnmowers ?(expireance)
       How complex is your engine is it a simple old chevy or ford or : is it a newer OHC with variable
        timing  ( these can be tricky)?
        Do you have enough Tools to remove the head sometimes special sockets for torx type bolts

Step 1 Get ready to grind heads HAH!

                                       CONSIDER  DO  YOU NEED TO GRIND VALVES ?
A . to begin with do a compression check and note what cylinders are low 20 or 30 %,(example some are 85 and some are 120 lbs.)  AND THEN
B .examine the movement of the valve lift before deciding to remove head see? if valve motion is moving like the higher reading cylinders valves,? movement look good" is the cam worn off?  if so fix cam first
Is or has the valve clearance become too tight (by adjustment or wear?)if so "adjust if possible first ....see notation #2B down page below  (then recheck compression)

                                     IF AND WHEN YOU DECIDE TO GRIND VALVES
ON OVERHEAD CAM MOTORS YOU PROBABLY WILL NEED TO TAKE THE CAM /S OUT 1ST

    engines with pushrod motors (not overhead cam) i recommend caution if loosening any rockers are removed  as some motors like chevy v-8s and inline 6 motors have a certain way to set them               ARE ROCKER ARMS IN THE WAY OF HEAD BOLTS?
   when you remove any rocker arms pick one and determine(count as you loosen) how many turns the nut takes to be loose enough to  get the socket squeezed into the head bolt then use this figure to turn any outher rockers(when loosening).    I usually only take as many rockers loose as i have to and then tighten them to the exact same amount of turns as you used to loosen the rocker arms (better a fraction loose then over tight)

1.To begin remove the head then clean it good
2. remove the valves springs ( use tool or make one)
3.place valve springs in box in a line maybe number the springs
leave the valves in the head in the same holes ( do not mix them up)
after this see if you can wiggle the end of the stem where it sticks through( valve guide) the head sideways if 1or two are really loose like .020 thousands beware you may to need have a guide installed at a machine shop for like 10 dollars o.k.?
4. place head on bench or piece of wood have a few small piece's of say 2x4x10" wood handy
5.hook up hand drill 1/4" or 3//8" best, too a suitable plug in a drill that can? run slower than 800 rpm is better i recommend 300 rpm is best
6. determine the size of the valve stem 1/4" or 5/16" 0r 9 MM. go to auto store buy the size of neoprin gas line that will squeeze onto the valve stem diameter tight or snug no more then 4 to 6 inches needed for several grinding job o.k.? cost around 1 dollar
7. get a small wood dowel or saw the end off a soft bolt 5/16" to say 3/8" it should be 3" long or 4" long ( nearly always)
8. take time to clean the valves one at a time if they have carbon caked onto them like wise remove any gunk carbon or rust from around the immediate area of the seat,it helps a lot when grinding
9. don't clean bent valves take them to auto store buy new ones for about 8 dollars each
10. if the car / truck ran good( 4 cylinders) and didn't backfire the intake valves may not need grinding, if v-8 engine they probably do so look at the faces and stems if there bright and show no signs of pitting maybe just grind the exhaust valves o.k.? used intake valves make better millage than freshly grinded ones do
11. if the exhaust valves are burned bad they may need to be faced/ if there usable at all and to help with keeping efficiant grinding time.
12 . i do not reccomend buying all new valves as the installed height sometimes need to be set (so use original valves if u can)
and it is nessessary to have the new valves Stems grinded to be the same length as the old ones
so using the old valves might be better unless you know what your doing o.k.?

notation #1Exhaust Valves

 BE IT Known !!! that exhaust valves get hotter :..and will wear ,or burn faster than intake valves: and therfore.. are to be expected" to be more likely to leak (power loss) and also and or on occasion be be bent dew to timing jump" if your motor is an >interfeirance type motor< (ask auto zoin )
BUT if YOUR Valves are bent you will still be able to fix your car / engine:you just have to buy new valves, and follow these same methods after installing any new valve it will have/ need to be adjusted to the right length"... pay attention... to factory valve lash specs: if so.


***** notation # 2B Are Valves too tight  (learn how to set em)

what i am cautioning is to be aware > how tight a valve assembly is / or has' become: <
  This tightness or shall we say over tightness is something called >Lash"< or Stem end clearance.
                                *   CHECK VALVE LASH WITH EACH CAM LOBE ON ITS BASE CIRCLE*

 Checking this (lash) is sometimes simple" :on non hydrolic lifters or barrel tappets a quick check
i will mention is simple checking to see if a tiny space is measureable between the
tappet or in some cases cam follower /rocker arm all non hydrolics require a small space
in the line of lift force it is there to compensate for the expansion of hot valve
stem expansion " it (the space mentioned  valve lash") it can be .006"(six thousands)
an inch.or it can be .010"(ten thousands) or rarely more, 
      ok if the valve is over tight it will hold the valve open" and that will cause a low compression(psi)
too mention futher the effect
of said over tightened valve lash include 2 symptoms low/r compression and :
    if on the intake valve :  this causes backfireing into the carb or intake manifold (fi eng-plenum)
on the outher hand an overtightened exhaust valve will become overheated
and that is very bad as more damage will concur as result!
          knowing if a hydrolic lifter or hydrolic valve adjuster is too tight is a little more complex
let me say check any adjustment nuts if thar are any as these type of settings are often discribed as non adjustable that is not to say they cannot be adjusted or even rarelie become to tight occasionally ok..................to explain takes time
             just try to see if you can compare any differance to any of the normal compression cylinders... If your car isnt (didnt) miss or backfire and has hydrolic lifters or adjusters
then dont worry" assume ther set right ( this is 4 hydrolic lifted valves only)
 
                                                 THINGS TO CONSIDER FIRST

       DO YOU KNOW WHERE ALL THE TIMING MARKS ARE
       DOES YOUR MOTOR HAVE A GAS TYPE CHAIN /BELT TENSIONER?
       Does your head have adjustable valves  
       Does your head or motor have hydrolic tappets
       Can you afford a Head Gasket set if so how much can you spend ?
       Are you using a used replacement head is it rusty ?
       Have you ever worked on cars motors or lawnmowers ?(expeiriance)
       How complex is your engine is it a simple old chevy or ford or : is it a newer OHC with variable
        timing  ( these can be tricky)?
        Do you have enough Tools to remove the head sometimes special sockets or torx type bolts
           
                                                                      LETS SAY DiFFiCulT "

         Okay old cheverolets or  old ford v-8s that are push rod type engines are the simplest to
          to manage The next groupe would be the 4 cylinder imports that either have pushrod     
         engines or only 1 overhead Cam
           
          following these would be the belt type duel overhead cam with belt  type motor and with
             adjustable rockers 
            4 cylinder motors with chain cam drive and and 2 cams also with balancer
          After this it would be assumed that  motors with duel over head cams with barrel tappets
          Then possibly the worst might be the duel overhead cam  v-6 with a chain drive 
           Beware of variable timing cams they can slip as they have 2 gears on one sprocket
                                           above is  in referance to order of difficulty "
         
        
       
     

Comments

[buhdieboy]

I am going to mention the GM engine 2.4 liter as it is a very difficult engine to remove a head from .The tennessee built engine used in chevys and pontiacs can and does break valves compleatly off , that can cause dammage to the piston/ pistons and rings . If you have a 2.4 engine dont alow the timeing chain to become worn and slip or you may need to change the whole motor . Besides possibly ruining the pistons or block the head is bolted to the block and timing cover with so many hard to find bolts as to be extremely hard to
remove the head from the rest of the engine .so its a lot easier just to chainge the chain befor it slips as you will only need to remove the timeing chain cover
to chainge the stretched timeing chain...and align gear marks i think you use 2 drill bits or bolts to locate the gears as they have holes drilled to stick the bits into as this is the location method for the 2 top cam gears also paint marks can be used it
you are precise enough with the releation of the upper and lower gears

[Yerboogieman]

The thing is, my engine has almost NONE of these parts.

[buhdieboy]

yesterday i had to check a freinds truck out it had unuseuale symptoms as the motor seemed to have all the correct requirments to start . That is, it had compreesion ,spark ,and distribution of spark ,plus fuel in the correct  amounts....  that is what the symtoms were ! thare was unburned raw gas on the plugs... thar was spark present at the wires at each cylinder ( i checked) . thar was only 92 lbs compression ( ?) a little low but i dont know what it got befor it quit running. Well heres what i figger happend and why expeiriance tells me that a car with compresion useually 100 lbs and with enough spark presnt at 10 BTDC  ( befor top dead center) has to start uless its flooded or not getting gas . basically i took the time to do a simple test but need more testing AS WE DID NOT GET IT RUNNING ... BUT THINGS BEING THINGS I CAN SAY EVEN THOUGH THE  ignition spark is proubably hot enough :
  More than likely the timing chain has slipped a few degrees out of sync that would make it have fair compression but still be fireing out of time (maybe even fireing on exhaust stroke) because this is a mechanically distributed engine .
  so im going to have to check to see if  so were going to have to get a timeing  gear set and install The point here is the unburned gas wet plugs are  the clue to arise suspician mostly because the engine is fuel injected
   next week-end......                                                                   thanks
   It could have bent some valves". but sometimes it doesent (strange)

[buhdieboy]

if you use the drills to face the valves(for pitted burnt vaves) you will still have to lap grind them to the head seat ok understand? this is to help the vavle grinding easier ok see pics"!

[buhdieboy]

make no mistake: this is not a liturary school"  what i am teaching hear makes use of common sense expeiriance something not useually teachable but must be learned by doing it is ( mechanics  a cold hard and calculated expeiriance most of you will not find it pleasant but a few motivated individules may find there lives are now headed in this direction
  thanks for reading and please understand  that i hope you can acheive
   something better then i have in life"

[burpreynolds]

Look, man.  I really want to know what this instructable says.  Is there any possible way you could edit in some punctuation?  Maybe not ignore the spell check quite so much?  I strongly suspect that you are a genius with machines, and that I could learn one hell of a lot from you, but this article is unreadable. 

And please don't just assume I'm just an a-hole venting some anonymous angst.  I'm way too old for shenanigans like that.  I just want to become the kind of mechanic my antique V8 deserves.  

[ahanix1989]

Any chance you could rewrite this so I can understand it? Run a spellcheck or something, I don't want to risk messing up my heads because I simply can't follow your blocks of text.

[trask]

I would strongly recommend buying the service manual for your car before you undertake a project like this. It will save you time and money in the long run. This is a good basic guide but there are things that are specific to your car that you will need to know.

[buhdieboy]

dont drop the valve keepers on the ground if your outside please do this on a smooth surface if they fall in the dirt there gone you will likely have to get a replacement pair

[buhdieboy]

do not i repeat do not forget to tighten your cam bolt after you get the 2 or 3 marks right i have dune this twice and once i had to get anouther cam and gear plus 8 valves and a day and a halfs work needless to say i looked like stupid it wasnt my car

[buhdieboy]

when alighning timeing marks !long as the crank (only when first installing head) is like 25o from the top for#1 piston on any 4 (and most 6&8)cylinder most importantly no valves will hit regardless but do not move the to shafts very far to bring to respective timeing marks ?ok? in fact disconect the battery , move the cam / crank or no cams position by hand.. Heads where the cams(removeable caped cams) are removed from the head obviousely the cam caps should only be tighted in the correct position when lowering the tdc center on about any eng use the same distance of around 25o tdc #1 ..clockwise i always then(2) tightn the head then imediatly(3) poisition(have in place?) the cam gear! temporaryily! or without the belt .. the imeadiatly turn the crank the counterclockwise 25o(4) back to top thats the way i do it & a good habbit to form . leaving your battery cables loose can prevent accidental movement after this its nessesary to install any belt idlers soemtimes backplates ect (waterpumps?)then positioning the belt tensioners is sometimes automatically dun by looseing the tensioner outher wise a pry tool or wrench for some the tensioner is turned to rotate tighter or prised to a tighter position the best policy is do not have the belt bango string tight it will fail from this faster then being moderately tight ok if you push against the belt on say a point away from any gear or cog it should take about 10 lbs of thumb pressur to deflect it say 1/4 " -1/8 if with the 10lbs the belt deflect only 1/16" its too tight ok thats the best i can discribe how to check tightness some times the old belt can be reused its not recomended not so if its defective (broken) the older the belt set its tightness looser do not mistakenly tighten any wires or vacume hoses in between the head and eng use a small compact mirror to look and also for looking at the marks on cam gear hold the mirror 45o and about 3 inches in frnt of the marks if you cansee the marks with a mirror then just forget this hint after tightening the belt rotate the engine recheck the belt tension did it change? ok check the marks on head and on the crank cog has either sliped or in the wrong place if so re adjust either setting till thar right retest again listen !when moveing or tighening cam bolts clamp cam at spot away from lobes or journals use vise grips or pipe wrench beware small metal chips and dont rest wrenc aginst any valve ends period use air wrench if you can to remove sometimes bolts to tight

[depayton]

Will this work on alum heads?

[buhdieboy]

obviously yess as aluminum heads have steel seats i need to do a chapter on the specifics of aluminum head peculiaritys, if you had overheating problems you will most likely need to have head pressure checked at a machine shop and have it milled levil otherwise you may be waisting your time but if you have the time too gamble th 70- 80 dollars for pressure checks and milling then go for it i have several times its been a 60/40 win loose or temporary fix toss up, also what differeces are you looking at from normal pressure for the given engine if you say? you have dropped (lower) 40 lbs on certain cylinders but have normal compression reading on 2 or more cylinders this says something to the expeirianced mechanic it indicates a bent valve or badly burnt valve (rarely seat)or a crooked or dropped seat or a stuck (ie bent or rusted)valve agin\ain much of what you will expect to find depends on the outher valve components its not impossible for the valves to be to tight on the lash or set wrong these are things experiance and familiarity will teach most importently beware especially on certain v-6 engs if the manual say set the engine piston #1 to some position outher then TDC or you will bend a valve when you bolt a head down but many cars you will need too set your timing marks on the head to the pictured position in manual the set the crankshaft to the normal marked position (most engs TDC*)before tightening the head bolts

[depayton]

I had a broke timing belt on an interference engine. Only two pistons had compression (180lbs+). Took the heads off, 8 bent exhaust valves that I could identify. Thanks for the insight but I just broke down and took them to a machine shop for testing and a valve patch job. In order to install he heads on this application, it says to set the crank to tdc then turn the crank counter clock wise 3 notches to install without more valve damage. Then once everything is installed put the crank on its mark as well as the cams and put the timing belt on. Does this sound right to you? this is my first head job.

[buhdieboy]

180 lbs is funny to high for a reg street engine has something spliedinto those cylinders i would expect 85 to 130 140 outside depending on cc and year your gauge may be off it used to be if a car had 90 it wasnt likely to start without pulling , pushing it 30 mph but some nissans got low cranking comps like 70-80! i guess its a tricky area oin that model most engines where expecting upward of 95psi. and more in general @cranking speed one thing here is always disconect the coil plug or wires befor testing comp if youi dont it may dammage your guage folks

[buhdieboy]

testing the valves for proper seating is possible if you seats are so hard in aluminum heads if the are worn or warped in the head it will be difficult for a novice to manage but i have discribed a way to acheive a fix remember more then likely your proublem will be on(certain) the exhaust valve/s tharby reduceiing some of the concerns for the aluminum heads intake seats i said more than likely so..with cast seats remeber the intakes are way more vulnerable to pitting if the motor set or had high milliage... anyway!

[buhdieboy]

you could use diamond lapping film cut as discribed for the 3m product it would need to be 45 micron or 60 micron grade (only for proublem/crooked seats) and expensine 10.00 for 1 3x6" peice

[buhdieboy]

buddieboy says if you can also order diamond lapping film in 45 micron grade or maybe 60 micron then it would be expensive but no doubt would help with the defective hard v seats issues where applicable but not often nessesary (proublem seats only)

[buhdieboy]

Wet/Dry Sheets Silicon Carbide' paper backed sheets. is equal to the mentioned carborundom ok" buhdieboy

[rmdc1]

Looks great. But do you have to use only Carborundum paper? What about 3M. I cannot find this paper anywhere and everyone I talk to says its just a name brand that is hard to find.

[buhdieboy]

Wet/Dry Sheets Silicon Carbide paper backed sheets. at automotive store yes (use for discribed method of squaring) for harded seats only this step not for cast seats nessesarily also lawnmovers have harded seats too ok? valves still require valve lapping after this seat squaring idea"

[buhdieboy]

sombodys going to say " reciprocating but expeiriace tells thar wasnt noticable differance .And also on the final finish grind allow the v.compound to become more worn by not changing it and the cut will be smoothest

[buhdieboy]

thanks gorillazmiko at last 1 comment ive been waiting for not that anybody needs to go back to school but this was my first attempt at publishing ... and i must say exciteing ! I wont sing thou" lol

[GorillazMiko]

cool!