problems with valvetrain, do i have to pull the head?

[calpolymustang]

ive had a tick come from the engine for quite some time, i thought it was rocker arm adjustment (too much play), so i adjusted the valves, but couldnt rid the noise. then i tried replacing a push rod which looked bent. later, i noticed that one rocker arm was sliding around on the valve and rotating in the axis that the tightening nut turns.

it appears that the rocker arm is eating up the side of the pressed in stud. also, the valve stem tip has been tappered; the roker arm has been at a slight angle and has worn away at the corner of the valve stem tip.

its only $30 to have a shop remove the stud and replace it with a screw in, but i dont know what to do with the valve. if i leave it and only replace the stud, then the stem tip may wear more and might eventually allow the arm to hit the retainer and drop the valve. if i change the valve, i have to pull the head

ive looked into cast iron heads that have been ported and have 1.94 / 1.60 valves, but dont know if there is much benefit to this. i dont mind the extra weight of the iron. alum are too much $

lastly, i thought that there was a company in LA that sold ported iron heads with big valves. does this ring a bell for anyone?

 

[Track Rat]

I've always gone by a simple rule when it comes to motors. A little bit extra $$ now might save you $$$$$$$$$$$$ later. Even the thought of droping a valve scares me enough to have it fixed.

I always good at spending other peoples money

 

[D.Hearne]

That worn valve and all the rest of the valve train for that valve should be changed at a minimum. This includes the lifter. Probably wouldn't be a bad idea to pull the heads , have them reworked or( buy new ones). Also do a cam swap. If one lifter is bad, it's time to change the rest and the cam & timing set. Be a good time to inspect the bores for wear.

 

[calpolymustang]

here are some pictures of the valve stem

 

[D.Hearne]

Pictures? What pictures?

 

[WORTH]

sounds like either a soft part,(maybe the rocker), or lack of oil to that valve, the oil comes up the pushrod threw the lifter, make sure your getting oil there. If the top of the valve is not straight, replacing the rocker wont help your gonna have to replace the valve.

 

[TT670]

oh yea pull that head before you drop a valve a make a mess. Have a reputable automotive machine shop inspect and repair it. Id bet that since the valve stem and stud are worn that the valve guide is worn too. Do the job right and you'll get alot more miles of service, anything else is a bandaid and catastrophe waiting to happen.

 

[calpolymustang]

sorry, heres the link for the picture

http://community.webshots.com/photo/153392014/153392562izndQp

im leaning to pulling the heads and installing screw in studs. the heads have been heavily ported and it appears that my 2bbl .030 (9.3:1 estimated) pistons will not accept 1.90s or maybe not even the 1.84 valves without enlarging the reliefs

question: will there be much benefit to buying a set of freshly machined 67-68 heads with the large circle push-rod hole? id still have to port them

 

[D.Hearne]

Those later model heads will require screw in studs and guide plates unless you like running rail rockers. Your present rockers won't work without the guide plates. I don't see why your pistons won't work with such a small cam, even with larger than stock valves. Unless the cam timing is way off.