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Discussion Starter #1
I need to adjust the valves on my 67 mustang with a 289 its not a hi po 289 i have a haynes book and it says remove the spark plug bring #1 cylinder up to tdc then push the rocker arms down so the lifters collapse down i cant get the rocker arms to move at all to collapse the lifter,i tried to slide the feeler guage under the rocker arm and it wont go in it says the guage should be set at min 0.082,im confused or im doing something wrong.

all i wanna do is get rid of the rocker arm tap im getting can anyone help me?
 

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what i do is take the valve covers off when the motor is off,then etheir cut the top off of an old valve cover and bolt it on so you can get to the rockers or use a piece of card board and lay it across the bottom of the head so you don't loose much oil.start the car and let it idle,back off slowly the nut of the rocker untill you here it start to click/clatter then slowly tighten the nut back down it untill the tick gos away! then go 1/2 or 3/4 a turn tighter and stop.do this to each rocker and the ticking should go away or you might have a weak lifter or valve.i've done this for years and its works for me,hope this helps.....Jim
 

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If you have hydraulic lifters, then put the feeler gauge back in the toolbox. Also, adjusting them with the engine running makes a huge mess and sometimes a fire. Run your engine to pump up the lifters then shut it off. Take off the valve covers. Put a breaker bar on the crank bolt and rotate until the valve you are adjusting is completely closed. Once the rocker is touching the valve with no gap, snug down the nut 1/4 to 1/2 turn. Done. If you have roller rockers then you have to also tighten the inner set screw. All 16 should take you less than 20 minutes. Good luck and have fun!
 

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When the rocker in question is on the heel of the cam meaning the valve is 100% closed, loosen the rocker up. Then while turning the push rod between your fingers slowly tighten until you just can't rotate the rod. You are now at the starting point. Now turn the adjusting nut 1/2 to 3/4 turn and you have set the preload and it should be quiet at this adjustment.
I also like the open top valve cover and never had a problem but I guess fire is possible if you let it make a mess.
 

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Discussion Starter #5
I replaced the lifters so i know its not a bad lifter ill give a few of the ideas u guys suggested a try thanks

it can hurt the engine if ya get the valves to tight cant it?
 

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it can hurt the engine if ya get the valves to tight cant it?
It most certainly can. You can bend the pushrods and valve stems.

For non roller rockers, I use the old valve cover with a slot cut in the top and adjust them with the engine running ... loosen each rocker until it taps, tighten until the tap stops, then 1/2 turn past that.

Don't follow the instructions you see most of the time that says to tighten until resistance is felt when spinning the push rod. The resistance you will be feeling will be when the lifter bottoms out and you run a risk of bending push rods and damaging valves. Zero lash is when all the slack is taken up in the push rod (no more up and down movement). Tighten 1/4 - 3/4 turn past zero lash.
 

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Discussion Starter #8
I did the cut a hole in the valve cover deal and adjusted them untill the ticking was gone put the valve covers back on and by the time i had that done i restarted the car and it was smoking out the tailpipe and i could hear a click coming from the exhuast pipe.

i think i tightned um to much
 

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Does the engine have a miss? You only want to tighten the adjustment about 1/2 turn after you loosen it to the point it clacks. It should miss before you bang something up. And as you adjust them, go slow so the lifter can catch up. You could have upset a valve seal...might just want to drive it for a bit once the rockers are adjusted. Again, don't go much more that 1/2 turn from loose and you should be good unless your lifters need to be replaced. How many miles on this build?
 

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The Ford manual says "Loosen the rocker stud nut until there is end clearance in the push rod, then tighten the nut to just remove all the push rod to rocker arm clearance. This may be determined by rotating and/or moving the push rod with the fingers as the stud nut is tightened. Then tighten 3/4 turn to place the hydraulic lifter plunger in the desired operating range."

A lifter normally goes to its full extension if there is no pressure on it. There is an internal spring that extends it.

Of course, this adjustment procedure is done with the cylinder at TDC of the compression stroke. It takes two rotatations of the crank to complete the job. You move the crank just 90 degrees at a time. From #1 TDC, it goes #5, #4, #2, #6, #3, #7 and #8. I have always used this method with no problems. Uncle Henry said that is the way to do it.
 

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Discussion Starter #11
Ive run into some kinda problem i put the car back toghter and took it for a ride and it smokes like a train and when i give it gas the engine sounds terriable kinda like a clunking sound.

the lifters are new.

could i have tightened the rockers to much and bent a valve? why would the car be smoking now?
 

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This is simple old school

It most certainly can. You can bend the pushrods and valve stems.

For non roller rockers, I use the old valve cover with a slot cut in the top and adjust them with the engine running ... loosen each rocker until it taps, tighten until the tap stops, then 1/2 turn past that.

Don't follow the instructions you see most of the time that says to tighten until resistance is felt when spinning the push rod. The resistance you will be feeling will be when the lifter bottoms out and you run a risk of bending push rods and damaging valves. Zero lash is when all the slack is taken up in the push rod (no more up and down movement). Tighten 1/4 - 3/4 turn past zero lash.

Does anyone prime the rockers prior to install? Big difference for initial lash before first start up. Setting final lash is best done with engine running and hot. Unless of course your engine is totally blue printed. LOL Old school, maybe just to much work for some.
 

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Does anyone prime the rockers prior to install? Big difference for initial lash before first start up. Setting final lash is best done with engine running and hot. Unless of course your engine is totally blue printed. LOL Old school, maybe just to much work for some.
Hot and running with hydraulic lifters is a messy waste of time. IMHO.

Here's how I do them, it takes less than one hour. With the engine cold, remove the RH valve cover. Disconnect the distributor (we don't want the engine to start). Use your bump switch to spin the engine until the second valve on the #1 cylinder is fully opened. This assures the first valve will be on the base circle. Loosen the nut as required until the pushrod is loose. Gradually tighten the rocker nut, wiggling the pushrod up-and-down. Do NOT spin it. At the moment the rod cannot move (zero lash) note the position of the wrench, and tighten the nut 3/4 turn. Repeat this on the other valve on cylinder #1, and work your way, in pairs, toward the firewall. When cylinders 1-4 are done, install the valve cover and repeat the process for cylinders 5-8.

I do something similar with mechanical lifters, except the engine is hot, and I run it before doing each head. My solid lifters run so smooth some folks don't realize they are solids.
 

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I'll add this, if you're adjusting the valves on a stock engine and it is, otherwise" in good mechanical running condition, checking the idle engine vac will provide a clue as to the valve setting being too loose or tight. A lower than normal vac is indicative of the valves, over all, being too tight.
 

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Didn't see the question asked but, sometimes, over the years parts get swapped around. Do you heads have positive stop rocker studs or fully-threaded ones?

Next, don't assume that just because you changed lifters that the problem can't be a plugged oil feed hole in the lifter bore.

Also, don't assume that 40+ year old rocker nuts won't loosen or studs pull out.

The accepted procedure (note that I didn't say correct), but the one that has been practiced the most, by most experienced Ford mechanics, is to adjust the valve clearances COLD, with the engine OFF, to zero lash plus 3/4 turn (1/2 turn if you're flogging the snot out of it).

Setting valve last hot, with the engine running, will typically cover up another underlying problem that will end up biting you in the azz later on.
 
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