Seating valves

[wesdabeersat]

Hey guys, my valves have carked it on my 2f motor, and ive decided to take the job up myself of replacing them..
im mechanically minded and have done a few decent jobs on my cars before,,,
my only question is with seating the new valves!
is there anything i should do to them to create a good seal when there closed?
or is just a case of putting them in and they will fit snug? (pending my seats are clean and not distorted) i have everything else sussed out, just not sure about that bit
cheers

[toy yoda]

if the seats are in reasonable condition...( otherwise its of to get a grind)
then its simply head upside down, apply grinding paste, slide valve into seat and using a lapping tool ( stick with little suction cup) put the handle betwenn palms of both hands and slide hands to roll handle!!!

thats about it in a nut shell......You can use a cordless or air drill set slow but its easy to go a bit to far if not done it before!!!

Note though...have you removed head and looked at /removed valves.....if valves on a 2f are stufed then odds are that they have sunk into head and will need a grind..sorry!!

[D Hall]

Also you can use a bit of bearing blue(obtained from a industrial supplier ) to check the contact of the valve.Just lightly apply the bearing blue to either the valve seat or the valve with a small brush,don`t brush on,but dab it on with the end of the brush.Gently tap valve into seat.Then you will see how much sealing land you have and if the valve seats are round.You will also note how bearing blue is a prick that gets every were and is a bugger to get of.:D
Cheers D Hall

[coopers308]

Both good replies and i wish you luck and hope all goes to plan, But as an engine reconditioner i've seen many many of these heads and they can either have very good seats after many miles in which case all they will need is the new valves lapped in exactly how toy yoda said then once springs are back on poor in some petrol/degreaser/kero into ports and make sure you have done a good job and no liquid is pooring out! But i've seen lots where the seats are very wide (i would say 2mm or over) and receeding into head (especially if on gas) in which case it's off to one us for inserts and/or just a re-grind unfortunately. Hope this helps.

[coopers308]

Just to add - what D Hall said about bearing blue - spot on, it can tell you so much before you even start the job - coz if the seats are distorted it needs to be re-ground straight away not worth trying to lap it in. Also check the guide wear they almost always need k-liners fitted.

[toy yoda]

And as a mechanic im glad there are blokes like coopers308 about the joint......because honestly my rule was simple.......

If i remove a head i dont refit it till it goes to the reco shop.....wether its for a face, crack & pressure test or a full valve grind..........Im more than happy to refit a nice clean flat tested head....and the resurrance that its not going to come back with an irate customer cause the head had a hairline crack under the cam tunnel!!!

[coopers308]

It's nice to know there are mechanic's out there like toy yoda who know the benefit of this type of work being done - not all engine reconditioners are just out to screw you for all your money! It may seem hard to hand over that kind of money for a head that tested fine with everything (pressure testing, vac testing valves, hardness testing and thickness test) and just needed a light skim to true the face......but it's worth it!!

[toy yoda]

and when the vehicle come back with a related problem............guess whos problem it is;););)

at least that way you stand a better that average chance of keeping people happy....there has been many a job that looks fine too my eye...but theres been a crack that cant be picked...only turns to horror later!!

[wesdabeersat]

all good, the motors only done 80,000 ks so shes hardly run in haha
the valve in question had a trangle split taken out of it..
so all good, started her up sunday arvo n ran like a dream
cheers for the info guys

[worthy]

And as a mechanic im glad there are blokes like coopers308 about the joint......because honestly my rule was simple.......

If i remove a head i dont refit it till it goes to the reco shop.....wether its for a face, crack & pressure test or a full valve grind..........Im more than happy to refit a nice clean flat tested head....and the resurrance that its not going to come back with an irate customer cause the head had a hairline crack under the cam tunnel!!!
tats my thoughts as a mechanic, its a small price to pay for peace of mind