ooookay, for those of you who remember my first string...car stalled, took it to a shop, paid 'em a shitload (i decided to trust a pro) to change my timing set (and clean out little metal and plastic teeth out of my oilpan). should've seen this timing gear (camshaft gear)...it was definitely just waiting to go...teeth were SO thin...i thik about six ended up going at once.

eeeeiither way. she runs. but something's gone horribly wrong with the valves. he's guessing #3 from the sound of it...did a compression test and said it was still getting 150, though. makes a HELL of a racket...and the worst racket is if you do more than caress the gas pedal it backfires out the carb REAL loud (no flames, though).

on a whim i decided to just get'er home and drove her about 10 miles at 25 mph. of course it took about 100 yds. to GET to that speed at such low rpm's (4 speed). he had it idling at 500 just to keep it from backfiring at idle...so had to keep from killing her has well.

and go figure she finally dies and won't start again half way up my driveway! ridiculous. she started again 4 hours later (she was overheating earlier) and i brought her in the garage. haven't opened up the valve covers yet...more time in the next couple days...but thought i'd drop a line and ask what i should look for since i've never done it before. i imagine with that sound (definitely something hitting something it's not supposed to be hitting) it might be obvious, but just in case, i could use a few different perspectives. she's definitely not driveable (but saved another tow)

got chiltons, got tools, got motivation. just need some direction.

'78 Z, 600cfm edelbrock carb (manual choke), torkerII intake, NEW TIMING CHAIN!

mahalo,
jess

Your cams flat, and you probably bent a pushrod when the timing chain went. I had this exact thing thing happen to me years ago. Timing chain broke, when I replaced it it wouldnt rev above 3000 rpm. When I pulled the 350, it had 3 bent pushrods, and a couple cracked valves. I built a 406 and grinned from ear to ear for years afterwards! Time to ditch that 350, its just plain worn out.

I don't know about a flat cam but a bent pushrod/bent or burnt valve sounds likely to me.
The pushrods are a easy fix, if it's the valves, not quite so easy. On that high of a milage engine, you are better off rebuilding it or replacing it.

Pull the valve covers & take a look to see if anything is broken or bent. Did he do a compression test on all the cylinders or just #3?

valve covers are off...oooooh my.

first to answer your question, yes he only did #3...and when i took off the valve cover, the #3 exhaust rocker arm was flappin' all over the place, pulled the pushrod and yup, bent. pulled four more...bent (i pulled only the ones that were loose). opened the other valve cover (passenger) and #4 exhaust was flappin'. pulled the rod...but so far it almost cracked in two (barely holdin' on). i have no idea how she ran at all.

SO...i guess if i'm already replacing 6 pushrods i might as well do 'em all. or is there any advantage to keeping the straight ones?

new question...since i already know the pushrods are whacked, should i dig deeper (i.e. pull the heads) and check the valves? (and lifters? i don't know how to get to them yet...) or do you think it's a good idea to just get a new set of pushrods and try that first...again this is my first time even taking valve covers off.

and another random question...how come only the driver's side valve cover has a pcv valve but the passenger's side just has what looks like some kind of air filter? they're chrome valve covers the prev. owner put in. is there air exchanged between the two sides?

thanks for all your help,
jess

PCV only needs to be on one side and a breather on the other...hence the 'brething' part...so you're not putting the crankcase under pressure or vacuum constantly.

As far as the pushrods...get all new hardened ones. And I'm sure 90% of the gang here will tell you to pull both heads, and drop them off at a shop to check checked out (unless you wanna do it). Then see how bad the pistons got whacked, cuz we all KNOW they're gonna have some smilies in them. Just hope for no cracks http://www.nastyz28.com/ubb/smile.gif

how dangerous would it be to try a new set of pushrods first?

Clarification question--- did the original timing chain let go while the motor was running or did you replace it just before it failed?

I would definitely do all 16 sticks at this point. Others maybe be bent (sliightly) such that you wouldn't notice it with a quick glance (roll them across some plate grass if you want to know for sure). Summit sells some decent quality stock replacement sticks for about $25. They are hardened (in case you ever want to use them with guideplats on a future engine) and the quality is plenty good for your application.

You DEFINITELY want to readjust all 16 valves yourself at this point. If you're not sure how- ASK! You'll get a lot of help.

The ugly part about bent pushrods due to a busted chain set is that the VALVES may be bent too. The pushrods are USUALLY the first thing to bend in the valvetrain, but that's no guarantee that a valve stem or two isn't also slightly tweaked. You'll never know, however, until you replace the pushrods and adjust the valves correctly.

to answer your question, yes, the timing chain went while driving (coming off a stoplight...and no i didn't gun it for once in my life :)...but i DID proceed to crank it about a dozen times messing with the mixture and idle screws....that didn't help.

AND, to make you cringe even more...when the timing chain was finally changed i decided to drive it home...real slow...backfiring through the carb and making all kinds of racket. that was pure stubborness, i was warned about what i could damage but i just wanted to get it home (i wasn't comfortable doing the timing chain and cleaning out the oilpan myself). surprisingly she DID make it home...but stalled halfway up my driveway...ridiculous. started up again after cooling down and i got her up into the garage.

flames welcome, haha. i'm new at this, it was a dumb decision, i know

valve adjustments....i know what chiltons tells me. trustworthy?

okay, so it's safe enough to drop in the pushrods, readjust everything, and work from there is what i understand. as usual (i live in hawaii) it'll take like a week to get anything shipped here (unless someone happens to know a local supplier) through napa, checkers, OR any online website...i will be back (but more comments/suggestions/tips are more than welcome).

thank you so much

Your cheapest bet is replacing the pushrods and see how the compression is doing. If you have screwy numbers then I would look at pulling the heads. You won't cost yourself any extra money if you try the pushrods first because you can re-use the ones you buy. Like Wayne said it is possible that you contacted one or more pistons on the valves. If you did this, then it is possible that you cracked a piston and that is bad news.

Take a compression reading of each cylinder, with all the spark plugs removed, the ignition power disabled, and the carburetor blocked wide open. Write each one down and charge the battery between cylinders if necessary. If your numbers vary more than 10% across the board I would start looking at the heads and valves, etc. If you have cylinders that read extremely low then you have problems warranting further review.

After you get the replacement pushrods installed, you can check to see if your valves are sealing by taking off the spark plug and putting your finger over the hole while cranking the car. If any cylinder does not have pressure blowing out of the hole, your valves are no good. Let me know if you want to sell the car.

So what happened? did you try a new set of pushrods?

sooooo if any of you even remember this string...yeah...had to postpone fixing my girl 'cause i was sent to another island for work.

either way, finally got new pushrods and started putting them in and everything was going good until i put one pushrod in and...it goes way too deep in the hole. if i poke around with it (trying to seat it) it sometimes gets stuck in something...can't figure out what it is. pushrod sits so low the rocker arm doesn't reach it. never seen what a lifter looks like in place...but i was wondering if this means a cam lobe is worn to hell and dropped the lifter. entirely possible since i drove the car home with apparently a broken pushrod and about six bent ones....not certain but this might'a been the valve with the broken pushrod.

soooo....yeah. i'm gonna fish around s'more and try cranking the engine briefly to maybe turn the camshaft a bit. any other suggestions? i really don't wanna have to pull the heads...or replace the camshaft...but she's my baby http://www.nastyz28.com/ubb/smile.gif anything for her.

thanks,
jess

It might have just spit the lifter out of it's bore. You'll have to pull the intake to tell for sure.

[This message has been edited by gregh (edited February 22, 2005).]

ooookay...small addition. got all but the troublesome pushrod in (exhaust #4, passenger side, fourth from front) and relatively tightened by handcranking a few times....and got her started. runs disgustingly rough, but runs, with a skipping click i read about earlier which was attributed to valvetrain trouble.

without the pushrod even in, that sounds makes me think the lifter is bangin' against something...for example the lobe is retarded.

also, i'm only getting oil pouring on four rocker arms on the driver's side and NONE on the passenger's side. i can't rev the engine 'cause it backfires out the carb with even the tiniest bit of gas...but what would do keep the oil from pumping? and i thought an open INTAKE valve makes it backfire...is the exhaust gas hot enough to ignite fresh gas/air when the intake opens?

mmm...time to pull heads, no?

thanks for any help.

jess

Pull the intake off first, if one lifter is missing from it's hole, there is no way you will have a reliable upper oiling system.
It will follow the path of least resistance & an open lifter bore is pretty low on resistance.
Don't run the engine anymore until you pull the intake & check/replace that lifter.

SWEET. popped the intake and all my lifters were in their bores, but the lifter in question was in pieces. the c-clip holding the spring mechanism had popped out, and the clip, pushrod seat, and the thin metal disc were sitting neatly next to the bore (with the rest of the lifter insside). i opened a good lifter to see how it went together, reassembled both, dropped everything in and started 'er up. no more backfires http://www.nastyz28.com/ubb/smile.gif

readjusting the valves was...interesting to saythe least. i pretty much got oil all over my engine AND garage 'cause i had a few valves overtightened to begin with. fun with tin foil...yay. but it seems to be working fine save for a weak start...i think my coil might be mad at me for some reason? much easier to fix, though (replace). might just be sluggish 'cause it hasn't been started in two months.

but yeah, fix timing and renew insurance and i think i'll be good...but temporarily i think. my headers are deteriorating in the ports, and my valves (what i could see of them) look like hell...in time...just glad to get it running now.

THANKS!

Good to hear you got it fixed & a little extra boost to the ego in the fact you did it yourself.

Now for all my help, got a cheap place for me to stay when I want to escape the cold next winter? http://www.nastyz28.com/ubb/biggrin.gif