lifters valvetrain

[stevesLX]

O.K. guys I give up I am ready to sell this heap. I have been trying to get this valve train right for 3 weeks now every night and still no luck. I have stock non adjustable rockers pedastal mount. The heads are factory to the best of my knowledge. 303F cam. I had head and block milled down and a 3 angle valve job. Before I had the work done I had some ticing going on and now I still have noise. So I went with longer push rods and guess what. I still have noise. I checked the preload on a few of these and I have differn't preload on all of them on one I have .053 on another I have .061 and on another I have .091. Something else I have noticed is on some of these nomatter how long I wait after I loosen the rocker arm when I torque it back down the valve starts to open. You can actually see the spring start to compress down. And it doesn't matter if the car has sat for 2 day or for 1/2 hour. It's the same valves it seems like that keep wanting to open. I know I am on the base circle also. I have done everything Crane Cams and Comp Cams ghas told me to do. If your are idleing you really cant hear anything but as soon as you give it gas it starts ticking. You can hear it inside the car and out. I give up. Also dont know if its related to this problem or not but the car feels like it doesn't always want to hit on all 8 cyl its sluggish here and there.

 

[stevesLX]

I guess theres nodody out here tonight that has any expertise in valvetrain. I guess all I am really after is does it sound like bad lifters or something else?

 

[Aryan15]

The valves should not open when you torque the rocker down. Your pushrods are too long and you are bottoming out the lifters. Youll have to get the rockers adjusted right before you can start on anything else. They sell shims and adjustable pushrods to help with this. Im not sure, but I think you can also convert your factory style non-adjustable rockers to stud mounted adjustables. Good luck.

 

[stevesLX]

O.K. thats cool and all but unles the machine shop really chopped up the lenths on my valve stems and they are all differen't lengths why do I have differen't preloads on some of these and the rest are the same. I already have shims under them. Like I said most of them I am within .020-.060 but some of them I am much higher and these are on the lifters that when you torque the rocker down the valve starts to open. These few lifters seem like they never want to bleed down either. They are always hard however all the other ones get springy or soft once they bleed off.

 

[stevesLX]

so if my pushrods are to long how come on most of my lifters if I torque the rocker down( non adjustable just the push rod moves but on the other ones the valve wants to open. I have tried 3 differn't length push rods and shims and the valves on some of these still wants to open.

 

[TheBocSez]

I going to agree that your pushrods are too long.

You said you had both the heads and block milled, both of which sets the head lower or effectively making the pushrod longer.

Then on top of that, you went out and bought longer pushrods.

I would imagine its possible that running the engine with excessively long pushrods, that you could have collapsed a lifter or two.

Also, I don't know the procedure for adjusting the valves with pedestal rockers, but maybe your just using the wrong sequence. Its possible that the lifter is not resting completely on the cams base circle when making your adjustment which may account for why some open the valve while other don't.

I made this mistake when adjusting my stud mounts, fortunately I caught the error before I tried to drive it. On the studs, you use the exhaust opening / intake closing method. I did it in reverse, adjusting the the exhaust when the intake stated to open and the intake when the exhaust was almost closed and ended up with a similar problem with the valves opening.

Once you back off the rocker, you also need to give the lifter time to return to the neutral position before adjusting it again.

Finally, make sure your rotating your engine in the correct direction when your doing this. I know it sounds simple, but I remember another member having similar problems and that was all it turned out to be.

May not be any of these other than the push rods, I'm almost 100% on those being too long, Just some thoughts for ya.

 

[stevesLX]

O.k. I am not doubting any one but the original rods that were in there were 6.258 and they were noisy after I put it back together. So I went with 6.272 and same thing (noisy) and only showing .010 preload so I stepped up to 6.300 and used shims and for the most part I have between .045-.050 preload now but on the ones that the valves are opening I have like .090 preload and thats with shims just like the other ones. Any I am turning the motor clockwise. I am torqueing down the intake as soon as the exhuast starts to open and doing the exhaust as soon as the intake is about to close. I have given it 5 minutes 2 hours and even a whole day and all my lifters with the exception of a few of them (4-5of em) will bleed down. 4 or 5 of them wont no matter how long you wait. I know we are just talking about the spring comeing back up but the lifter bleed down I thought maybe use ful info also. Not sure how you can tell if you have a bad lifter. I am just to the point that I am ready to go out and drop 130.00 on new roller lifters and dont want to in not neccessary. The car had some ticking when I bought it along with blow by and everything else. The car has 80-90000 miles on it when I bought. I had the lower end rebuilt.

 

[superhuaman]

why are you rotating the engine clockwise? it runs counterclockwise

 

[stevesLX]

Yes indeed it does run counterclockwise but if you are hand rotating it from the outside you turn it clockwise. Sitting inside the car the motor is turning ctrclockwise which means if you are outside in front of the motor it is turning clockwise.

 

[Busted07]

why are you rotating the engine clockwise? it runs counterclockwise

are you talking about when youre sitting in the car, or facing the motor?

 

[5spd GT]

steveslx - Your right about the orientation of the engine rotation.

I have a few lifters that do that as well, 3 to be exact. They don't have a 'preload' to them. When you turn the rocker nut to tighten down, it will almost instantly lock up. I wonder if that is what yours does as well?

Do you have a quick pic of the rocker arm sitting on the valve stem to see how 'centered' it is?

Also, from what I noticed I just personally watched my lobes to see when they go to base circle. Just keep your finger on them to keep pressure and a point of contact between the lifter roller and cam base. Then when it goes down and doesn't move for a little bit, you know you are on the base circle. Sometimes looking at the intake or exhaust to see if the other lifter is going down can be a bit deceiving in my opinion.