Tuffnut

Here’s the deal. I set my hydraulic flat tappets/ valves too tight. I thought I had done it right. Key word, thought, using eoic method. I know don’t beat me up. I have already beat myself up. I take full responsibility. My finger roll was too tight and then I went 3/4 turn to one full turn. I set them all that way. I cranked the engine over sounded good. Never started. Kill switch was on. The more I thought about it the more I realized they may be too tight. I redid them Using the same method but at the slightest bit of friction on the finger roll I tightened them 1/2 turn no more. I did a baseline compression test a month ago 188 - 195 Before adjusting the valves. Because I was afraid I may have done something wrong I decided to do another compression test tonight after the valve adjustment. All cylinders were 188-192 but #1 and #2 90 psi and 140 psi. So now I’m pissed, mad and disappointed. I backed all the valves off on those 2 cylinders with lots of lash. Did a leak down test and heard air coming out the exhaust on both cylinders. Sounds like damaged exhaust valves. Question would there be other other damage? Should I pull the heads with the engine in the car?

Rookie mistake, learning the hard way😭😂

joe_padavano

Are you saying that you had the valves too tight, but you never actually started the engine? If so, there's no way you hurt anything, unless the valves were waaaaay over adjusted and you kissed the pistons, but I really doubt that. I think the low cylinders just aren't adjusted correctly. If anything, back off the adjustment on all the valves and do a leakdown test. If it passes, you're good to go.

Tuffnut

Joe, I believe the valves were too tight. I cranked the car over with them too tight. Never run it though. I can see some carbon missing on the piston when looking through the spark plug hole. I loosened the rockers right off. Sloppy. Lots of lash. Did a leak down. Air out the exhaust. You would think it would bend the push rod, not damage the exhaust valve.

joe_padavano

Did you do the leakdown with the rockers all backed completely loose? If so, yeah, sounds like you might have bent a valve. Sorry.

Tuffnut

Yes that is correct. Leak down test performed with lots of lash tension backed right off. What damage could that cause other than bent valves? Fixable by removing the heads with the engine in the car?

joe_padavano

Unfortunately, the only fix is pulling the heads and replacing the damaged parts. What rockers are you running? Also check the pushrods, as you may also have bent something.

Tuffnut

Comp cams adjustable roller tip rockers.

joe_padavano

Got it. I used those on the last 455 I built for my 67 Delta.

Sugar Bear

If you didn't run it the pistons will be ok. As stated it may have bent a valve or two and a few pushrods. Don't kick yourself about it, that is how one learns.

Yes, it's fixable by removing the heads with the engine in the car.

Good luck!!!

Tuffnut

Thanks guys for the responses. By pulling the upper and bottom rad hoses off, will it drain the engine enough that no coolant will be present in the heads during removal. Don’t want to get coolant down into the pistons and crank. Never pulled heads on an engine in the car. Can I reuse the same arp head bolts? I know new gaskets are in order along with other damaged parts.

bccan

Just for clarity, did you back off ALL the rockers before testing? Just thinking about exhaust crossover if you were in the middle of the banks. It’s not all that easy to make contact in Olds engines but certainly not impossible. I’ve found on some brands of the lifters that 1/8, no more than 1/4 turn after contact is the safe place to be. I’m hoping things turn out easy for you but looks like you’ll find out soon.

just saw your last post. I like to remove the block drains down by the engine mounts to make sue coolant is clear of deck. I usually cup my hand or seal a rag in stat opening and use a blow gun tin hopes of blowing out some extra coolant before removing intake, same with rear heater hose fitting on intake. It can’t hurt and takes about 60 seconds.

Tuffnut

I didn’t back off all the rockers. Only the ones for cylinders 1 and 2 front 2 cylinders as that is where my compression test was low.

olds 307 and 403

Pull the intake. When my cam was failing I over adjusted the valves. I bent and actually broke a pushrod. You could have bent two pushrods holding those valves open. My heads seem to be fine, you will destroy little 5/16" pushrods before anything else. I personally will never set valves with the intake on again, too much guess work unless you really know what you are doing and doing it often.

Tuffnut

It’s possible the valves may be stuck. I hope but have my doubts. I have the rockers backed completely off. No tension. I can press the valve down. Just not sealing. Intake is coming off. See where we go from there.

Tuffnut

So I took the car to the shop that did my motor. They did the same tests I did. Both exhaust valves leaked. They pulled the heads for me. Found the the valves were not damaged. Were not completely sealing because of a carbon pc stuck on the seats. Happy there was no damage. A little frustrated with myself. Could have started it and run it and cleaned it out. Didn’t know. Didn’t want to matters worse. I thought I would error on the side of caution. I did a compression test 2 weeks before adjusting the valves. Everything perfect. 2 weeks later adjusted the valves twice. First adjustment possibly too much preload. Never started the car. Cranked over for another compression test and that is when I noticed the compression issue with 2 exhaust valves. Coincidence that during the compression tests or valve adjustments some carbon became logged on 2 exhaust seats. So I changing back to a 180 stat from a 160. Still going to run 2 heat ranges cooler with .040 plug gap. Run some combustion cleaner through yearly before oil change. Running Lucas hot rod oil with zinc.

Fun71

I say you did the right thing being cautious and verifying what the issue was before running the engine.