Guess I screwed up valve adjustment
 

Well, I went to fire up my "new" 455 and it won't start. I've got gas and spark but no compression. Thankfully I didn't turn her over very much to figure out that I had no compression. It didn't sound right as it spun over. No S$%^ - right!!!! Anyway, I figure I messed up adjusting the valves. I did em when the valley pan was still off so I just looked at the cam and adjusted them when on lowest spot. Took the slack out and went 1/2 turn. Then I would turn motor over by hand and do the next one, right down the line. I don't see how I could've messed that up, but I'm pretty sure I did. Oh well, next weekend maybe it'll run!!!! Glad I didn't seal those valve covers yet. Wanted to get it running and then seal em. I'll look on here for another method. This time with the valley pan on and looking at the rockers. Suggestions, or does it sound like I am on the right track? :old: :usa2:

Get it to TDC #! BOTH VALVES CLOSED, then turn it by hand til #1 exh rocker just moves , then adj Int on #1, then turn it over til #1 int valve opens and closes halfway, then adjust #1 exh, then do the next cylinder in firing order as u just did number 1 etc.

I spin the pushrod in my fingers while tightening, until I feel slight resistance. Then I go a half turn or so. You have to get a feel for the point where the plunger spring starts to compress

As a side note, are you certain that the timing gears are aligned right? I' ve been there before.

Sounds like you over adjusted your valves. Had the same thing happen. Had fuel and spark but was a no go. Kept rechecking timing, then I checked compression and had none. So I ened up setting 1 one to top dead center and filling cylinder with air. I could hear it leaking past in to intake and out exhaust .

You have an adjustable valvetrain...right?

Fastest, simplest way to adjust valves on a hydraulic-lifter engine THAT ACTUALLY HAS AN ADJUSTMENT AT THE ROCKER ARM:

1. Loosen all rockers so that the pushrods have up-and-down play.
2. Tighten all rockers so the pushrods have NO up-and-down play, but don't tighten beyond that point. (Tighten to "zero lash".) THIS IS CRUCIAL.
3. Turn crankshaft exactly one turn.
4. SOME rockers will be loose. Tighten ONLY the loose rockers until you have zero lash.
5. Tighten ALL rockers "your choice" of preload: Most folks go 1/2 turn, some like more, some like less. Be sure to verify what the lifter manufacturer/reseller specifies for your lifter part number.
6. Put the valve covers on, and have a beer. Say "thank you" to MotorDaddy, who taught me this procedure. You're done.

The way you did them 1st should have worked for you. With the valley pan off turn the crank over by hand until the 1st valve is on the bottom of the lobe, then turn the push rod with your fingers & tighten the rocker until you feel a very little drag on the push rod. You won't be able to move the push rod up & down at all. Tighten the rocker nut 1/2 turn & tighten the allen nut inside the poly-loc, & your done with that one. Go to the next rocker & do the same thing. Be sure to hold the rocker nut with the 5/8's wrench so the rocker nut doesn't turn when you tighten the allen nut in the center of the poly-loc rocker nut. You are using poly-locs to adjust the rocker arms aren't you????? After you have adjusted all the rocker nuts that way you are all done & the valve train is all adjusted & done & ready to start.

That's exactly the way I did it, so I don't know what went wrong. Looking directly at the cam and lifters with valley pan off seemed like the BEST visual. Guess not. Oh well. I'll do the "motordaddy" method next weekend. Seems like the easiest way. Thanks for all the help. Can't wait to hear this new motor run!!! And I will check for any troubles like a bent push rod!!! Yes, using poly-locks.

Doesn't make any sense. If you had the valley pan off and adjusted on the base of the cam you should have been ok..

I'm willing to bet you had all the rockers and polylocks on and while turning it over you may have forced the plunger down in the lifters, which when adjusting polylocks caused the valves to hang open.

What lifters are you using?

Charles

Are you using roller lifters? I found that some of mine would easily push down the plunger by hand. This caused problems for me even when I hand tightened down the nut, or when checking by rolling the pushrod to check for resistance.

How do you know that you have no compression? Did you do a compression test, or are you just going by what it sounds like when cranking?

Yes, that's what I'm talking about. You can end up tighten too much and hang the valve open.

Charles

Did you soak the lifters in oil before you put them in? Also are you sure the timing is correct by that I mean do you have the timing gears & chain on correct?? When you tightened the rockers down did you make sure the plunger in the lifter didn't go down into the lifter bore? If you tightened the rocker to much you can end up with the same thing to. If you tightened it even enough to go down into the bore a little bit will also cause that to. I'm only asking this but did you make sure you installed the dist. so it's wired so it goes counter clockwise. Pontiacs are not the same as a chevy. I'm asking only because I don't know how familiar you are with Pontiac .

Here is my chart. When the valve on the top line is full open, adjust the valve under it.

Full Open- 6E 4I 5E 3I 7E 6I 2E 5I 1E 7I 8E 2I 4E 1I 3E 8I
Adjust____1E 7I 8E 2I 4E 1I 3E 8I 6E 4I 5E 3I 7E 6I 2E 5I


This insures you are 100% on the base circle.

Flat tappet Lunati lifters. Roller rockers. No I didn't soak the lifters beforehand. (That was my first mistake). Yes, dizzy and timing marks are correct. I checked comp. with my finger over spark plug hole while wife cranked motor over with starter. I made sure not to crank very much. When she didn't fire right away, I started looking for the problem. How would you know about "When you tightened the rockers down did you make sure the plunger in the lifter didn't go down into the lifter bore ' ? You wouldn't be able to see that, would you? I'm going out now to take a look. I'll check push rods to make sure I didn't bend one and readjust after spinning oil pump again to help get oil into lifters.

No bent push rods. Lots of Oil seems to be getting to all push rods, rockers etc. Lifters "feel" correct as in plunger not collapsed into lifter bore. Should I continue or not bother and disassemble intake and valley pan to soak lifters? Or will they (seems like they already have) fill up by spinning oil pump? And then "down the road", how quickly should I change the break-in oil? I am getting conflicting answers to that with most saying right away.

Panhead you can see the plunger go down if you look at the top of the lifter. Remember that it only takes about 60th's to get the lifter to tight. When you first start the car the lifters will fill up in about 1-2 min's. or so. But just priming the engine will take it a lot longer ,, depending on how strong the drill your using. If it were me I would take the intake & valley back off & look to make sure you don't have them to tight. If you adjusted them when they were low , or not filled up when they do fill you may have them way to far adjusted up & now the valves are just all hanging open. Also you should leave the break-in oil in for no more then 500 miles. But you are proberly safe to about 1000 miles.You don't have to remove the lifter & soak them now because you have pumped some, most of the oil needed into the lifters now so just leave them in. But back off the rocker nuts & let them sit for about an hour before you go back to it to adjust them. That will give the lifters a little time to relax & let the plunger come up to it's normal position. I would though reprime the engine to make sure all the lifters are pumped up. I had 1 engine that took about 20 min's to completely pump up. But that was an odd ball & most will pump up in about 4-5 min's . But if you R&R the dizzy & reprime it you will know that theres oil up top & all the lifters are full. Depending on the gaskets you may be able to reuse them. The intake you should be able to Y the valley pan gasket if your real careful you might be able to if you use some silicone sealer along with the old gasket.