Broken Inner-Dampner Valve Springs...?
 

Hey guys, just thought I'd ask for some opinions from some of you guru's out there....lol...about a month ago i was on the freeway driving home from work and after exiting the freeway, i come up to the red light ahead and notice it sounded like it wasn't idling on all cylinders, like a fouled plug or something....so i babied it home and the next day i pulled the plugs out and removed the valve covers to find oil on number 8 cyl. spark plug, 5, 6, & 7 were oily too. looked around at every valve spring and took a small magnet to each spring. started to notice i could move the dampner springs on 5, 6, 7, & 8. but get this, only on the intake valve springs. upon further inspection and a brighter drop light, saw pieces of the #8 dampner spring in valley of head bolt space towards the back of passenger side cyl. head. not good. and also saw tiny blue chunks of valve stem seal everywhere oil would gather in head...

I guess i should tell ya specs on motor..
1977 Chevy 350 block bored .040 over, scat rods and crankshaft 3.48" stroke, flat top 2 valve relief pistons w/coated skirts. comp cams xtreme energy 268H camshaft pn#12-242-2 (.477"int, .480" exh.). Bought matching lifters for cam, and comp ultra gold 1.6 rocker arms. Bought Patriot Performance Freedom Series Aluminum heads (p/n 2169). 2.02/1.60 valves, 185cc intake runners, and springs are rated up to .575" lift int & exh. Now here's the kicker with the heads, a tech. card came with the heads in the box, said i will have to measure pushrod length. so i bought a pushrod length checker and found out i had to buy .020" longer pushrod (that set the roller tip of the rocker arm dead center on top of valves...) adjusted rocker arms properly in sequence from chilton manual. and wa-la, spent all that money on this motor and bam. broken springs. not how i wanted to see this motor end up with only about 2500 miles on it... if that. :(

I talked to Steven at Patriot Performance and said he has never heard of any problems out of those springs and still use the same springs as of today, since day 1 of production. he said i could order another springs from him, but the question still hangs around my head. will these springs break just like the first set did? if so, how long will it take to break???

I'm so friggin frustrated. just feel like buying a wrecked ss camaro for the drivetrain or an ls3 setup. :metal: ha!

Re: Broken Inner-Dampner Valve Springs...?
 

I went through this with AFR on my 468 several years back. They use what are thought of as high end springs from PAC. I broke 9 inner springs (not dampers but an actual inner spring). Worked fine on the dyno and about 2,000 street miles.

Ironically my engine still ran fine, I had pulled the covers for another reason and found that :lol:

The explanation I got from AFR (and I'm sure they were trying to cover their butts) was that there was a bad batch of springs floating around the market that others also had issues with, and it had since been addressed.

I've also heard of this happening in recent months with other springs. Seems every so often cylinder head manufactures want to blame a bad batch of springs hitting the market.

I don't know how much truth there is to that, but I feel your pain. There is that worry that some smaller pieces could have made it down the drain holes and into the oil system (unless you epoxy some screens at the drains, I do that on all the engines I build).

With that small cam you have, a single spring with damper is enough spring pressure. You'll have to check the valve guide bosses if it has chewed up your seals, it could beat the tops of the guides too (it did on mine).

Hopefully it's not too bad and a new set of springs and seals will get you back up and running.

Re: Broken Inner-Dampner Valve Springs...?
 

Oh wow. Damn, AFR's? wow. wouldn't expect that from them either. Yeah, keyword: "hopefully" (haha) just a bad batch of springs. i really do hope it was a bad batch. lol. when i tore down the right side and saw the condition of the valve seal, it had to have just happened for my seal on #5 int. to just start barely being pulled up out of the recessed area for the seal. It's kinda like the inner spring is twisting clockwise-downward angle. My father and I first thought the piston was hitting the valves, but its weird how its only the intake valves.... IDK! I give up for today! I'm giving myself a headache thinking about it....

Thanks for the information FirebirdJones! will definitely look at the guides when new springs come in and new seals. IF they are toast, my mind will be too! :lol:

Kris

Re: Broken Inner-Dampner Valve Springs...?
 

I'm willing to guess your guides are probably okay. Sounds like you caught the problem fairly quickly.

In my case, I didn't even know the inner springs were broken as it was running fine. Hard telling how long mine was running like that. Probably had alot more time to do some damage :lol:

Yeah I didn't expect it from AFR either, then found out they sent the heads with the wrong springs in the first place after they spec'd the custom camshaft through Comp, you'd think they would get the springs right....

They wanted to take no blame though...

You'll be up and running in short order as soon as those parts get there ;)