Bent Pushrod

[stevesLX]

Well low and behold now not only do I still have valvetrain noise I have a bent pushrod. I am clueless as to what could possibly be giving me all these headaches. So after replacing lifters rockers and having a preload of .045 I get a bent pushrod. So last night I doubled up my gaskets on the valve covers and replaced my pushrods with some new ones and it is still noisy. So I pulled all my new roller rockers off and stuck the factory ones back on and its still noisy with those to. I dont know what else to do. My pocket book is broke now from chasing parts and I have adjusted this valvetrain every single way possible. I am starting to wonder if the machine shop didn't screw something up when they performed the work on my heads and block. My rockers are non adjustable pedastal. I have gone thru these the way Crane Cams says to do it, Comp Cams way, The haynes manual way, and I have gone to TDC compression and adjusted my preload on them that way and still nothing but headaches for 3 weeks now every single night after work and every weekened I have worked on this valve train crap. I really need some help.

 

[stevesLX]

I just talked to the machine shop and they say the chances that a valve slapped one of my pistons is slim to none but they said to check and find out real quick I should do a compression test. They told me to loosen up the rockers first. Does anyone know how much I should loosen the rockers up? They said by doing this I should be able to tell if any of my valves are bent.

 

[302RollinHard]

You loosen up the rockers until the valves seat. When you can giggle the rocker with your hand you are loose enough. They tell you to do this so that you can be sure the valves are in the closed position.
Did you ever measure for the correct pushrod length? Not having the pushrod completely in the center (not hard to mess up on a closed up top end) of the lifter cup can give you erroneous setting and when the engine fires up they can center themselves and give you some noise. It is somewhat difficult to get things set up while the lower intake is on and you can't see everything. I know this from very recent experience.
I would suggest taking it to a trusted shop, spending the cash and having a pro set it up. All this aggravation is worth money IMHO.
The bent pushrod is key here. You got some problems either with geometry or with how you are setting things up.
Also just remember in valvetrain geometry, a hundredth of an inch or few thousandths is like a mile.

 

[stevesLX]

Yes I had the lower manifold off when I set all this up for the 100th time the other night. That is when I replaced my lifters and rockers and I measured my pre load on some of them then also. I drove about 147 miles yestarday and it was still noisey all day yestar day and I had someone listen to it at a auto service shop and they said the rockers are hitting the valve covers. They said to double up the gaskets until you can buy taller covers. Well just to make sure this was indeed the problem I tore all my rockers back off and that is when I discovered the bent push rod. The rockers do show some evidence of hitting the valve cover here and there. After doubling up the gaskets last night its still noisey. So I tore it all back apart and put my factory rockers back on which are smaller than the roller rockers I have and its stll noisy.

 

[stevesLX]

O.K. I took the car by Ford today and a speed shop and they both said just by listening to it I definitely dont have pistons hitting valves but I definitely have valvetrain noise. So when I got home I tore it back down again and I took a black sharpie and colored the tops of all my valve stems and went back thru everything following the firing order and started it left it idle for a few and gave it a couple of low revs and then pulled my non adjustable roller rockers off and on 6 stems I had a wear mark right across the center and on 4 other stems I had a wear pattern that went across the center but it looked as if the valve stem actually turned about 1/8th. The marks were straight across center but a wider wear mark than the other 6 and after I pulled the rockers off of them the mark was like 1/8th of a turn like the stem moved around some. And I had 6 that valvestems that no longer had anything left on them. The tops of them were shiny again. So if anyone oput there can help I'd appreciate it.

 

[302RollinHard]

Steve,
Don't check rocker runout with a running engine. Mark the tops of the valves like you did and rotate it by hand a couple times. This will tell you all you need to know. A more narrow wear pattern is more important that an exactly centered pattern IMHO. I think you need to just take the time to measure your needed pushrod length with a solid lifter on every cylinder and go from there. Non-adjustable valvetrains can be a little tricky sometimes.

 

[gnx547]

stevesLX, any new info? Have you solved your valvetrain noise?