I hear piston slap.

 

I hate to say it, but typically Vortec heads need valve guide mods(machined shorter) for cams with over about .450 lift w/stock 1.5 ratio rockers, much less 1.6 ratio rockers as evident by the valve seal debris you found. The bottom of the spring retainers were probably crashing into the top of the valve guides pretty hard if not catastrophically.
You may have bent all of your pushrods and thats what you hear hitting in the slots in the head or trying to move the rockers sideways? Definitely possible if the previous owner didn't have the guides machined. I'd pull the pushrods and roll them on a glass tabletop to check if their straight. Someone else chime in on this please as I may be full of it!
Did you replace all of the valve stem seals? I'd have a good look at the retainers and locks while I was at it.
Do the heads have self guiding rockers or guide plates. Not both.
Hope he checked valve to piston clearance as well. I would think a compression check would tell if a valve was bent. I'm probably just too paranoid about stuff like that, but after seeing seal debris???
Good luck!
ssmonty
PS I never listened to the video.

 

I hate to say it, but typically Vortec heads need valve guide mods(machined shorter) for cams with over about .450 lift w/stock 1.5 ratio rockers, much less 1.6 ratio rockers as evident by the valve seal debris you found. The bottom of the spring retainers were probably crashing into the top of the valve guides pretty hard if not catastrophically.
You may have bent all of your pushrods and thats what you hear hitting in the slots in the head or trying to move the rockers sideways? Definitely possible if the previous owner didn't have the guides machined. I'd pull the pushrods and roll them on a glass tabletop to check if their straight. Someone else chime in on this please as I may be full of it!
Did you replace all of the valve stem seals? I'd have a good look at the retainers and locks while I was at it.
Do the heads have self guiding rockers or guide plates. Not both.
Hope he checked valve to piston clearance as well. I would think a compression check would tell if a valve was bent. I'm probably just too paranoid about stuff like that, but after seeing seal debris???
Good luck!
ssmonty
PS I never listened to the video.

When I put the lower lift cam in I checked for retainer to seal clearance - coil bind, bent push rods etc.. I also replaced all the valve seals. I just did not really know how to check lifters but they seemed fine?

As far as piston slap or a crank bearing it is possible I dont have any faith that the guy knew what he was doing.

I just pulled a plug wire one at a time with no change in the way this engine sounds. I read that it will determine if it is a rod knock or piston slap but This is my first rodeo.

 

I watched the video and could'nt help but notice the vacuum gauge fluctuating at idle or so I thought. I would have though with that small a cam it would have been more steady. Kinda looks like a valve sticking or out of adj. if I'm not mistaken. They make a noise kinda like that when they have too much slack in their adjustment. Did you use polylocks w/set screws? Sometimes(often) they come loose. You did say it seemed loudest at the stud.
I also thought I heard a growling noise kinda like a cam/distributor gear under load. Could the distributor be bottoming out in the oil pump? Do you have a melonized gear on the distributor? I don't know what other accessories you have on a boat that may make that kind of noise?
ssmonty

 

I watched the video and could'nt help but notice the vacuum gauge fluctuating at idle or so I thought. I would have though with that small a cam it would have been more steady. Kinda looks like a valve sticking or out of adj. if I'm not mistaken. They make a noise kinda like that when they have too much slack in their adjustment. Did you use polylocks w/set screws? Sometimes(often) they come loose. You did say it seemed loudest at the stud.
I also thought I heard a growling noise kinda like a cam/distributor gear under load. Could the distributor be bottoming out in the oil pump? Do you have a melonized gear on the distributor? I don't know what other accessories you have on a boat that may make that kind of noise?
ssmonty

I took off the belts so I know that it is not the water pump, alternator or power steering pump. I also pulled the drive.

And yes the vacuum gauge does fluctuate a little bit at Idle

I am not sure about the distributor gear it is a stock GM Steel gear and GM cam. The distributor did come off a 305 and is a thunderbolt 4 ignition if that tells you anything? I did check the coil primary resistance and got 1.9 ohms and suppost to be .6 - .8 but I am using a fluke digital so I am not sure if that is accurate.

When i put the new cam in I thought to my self there was allot of cam walk until I put the cam gear on and that took the slack up is this normal on a roller cam? there is no cam button just a plate that holds cam in

 

After installing the cam retaining plate and timing chain cam gear there should be almost no cam walk that you can feel.
Did you use a stock timing chain set? A double roller may be grinding the front of the block if not clearanced. You would see evidence when you change the oil, but it would be too late by then, at least for the chain. I should shut up now.
I wouldn't think you had piston slap on a new build if you have receipts for the machine work. Every time I've had a block bored, they ask for the pistons so they can bore them to fit.
I know its messy, cramped, and awkward, but you ought to try to adjust the valves with the engine running. Get an old valve cover from the salvage yard, cut the very top out of it with a cutoff wheel and be-burr the edge good. Install it in place of yours on one side after the engines been warmed up a bit(easier said than done I know). Start the engine and backoff the 1st rocker slowly (say #1 exhaust) until you hear it clacking, slowly tighten it until it quits clacking. Do it a couple of times until you know just where the sweet spot it quits clacking is. Then slowly give it 1/4-3/4 turn more CW.(I prefer 1/2). The lifter may not bleed down enough for 1/2 turn and hold the valve just off the seat and the engine will run rough, it may smooth out in a few moments time, if not, you may have to settle for 1/4 turn preload.
Then do the #1 intake and so on until you have the drivers side done. Obviously do the otherside. Shouldn't have to worry about adj. the valves again.
ssmonty

 

After installing the cam retaining plate and timing chain cam gear there should be almost no cam walk that you can feel.
Did you use a stock timing chain set? A double roller may be grinding the front of the block if not clearanced. You would see evidence when you change the oil, but it would be too late by then, at least for the chain. I should shut up now.
I wouldn't think you had piston slap on a new build if you have receipts for the machine work. Every time I've had a block bored, they ask for the pistons so they can bore them to fit.
I know its messy, cramped, and awkward, but you ought to try to adjust the valves with the engine running. Get an old valve cover from the salvage yard, cut the very top out of it with a cutoff wheel and be-burr the edge good. Install it in place of yours on one side after the engines been warmed up a bit(easier said than done I know). Start the engine and backoff the 1st rocker slowly (say #1 exhaust) until you hear it clacking, slowly tighten it until it quits clacking. Do it a couple of times until you know just where the sweet spot it quits clacking is. Then slowly give it 1/4-3/4 turn more CW.(I prefer 1/2). The lifter may not bleed down enough for 1/2 turn and hold the valve just off the seat and the engine will run rough, it may smooth out in a few moments time, if not, you may have to settle for 1/4 turn preload.
Then do the #1 intake and so on until you have the drivers side done. Obviously do the otherside. Shouldn't have to worry about adj. the valves again.
ssmonty

OK i will try it I have an extra set of valve covers, and also I did a compression check on each cylinder and basicly they are all between 130 - 150 pounds biggest gap was #1 was about 130 and #6 was about 150

I did research on piston slap and I guess alot of engines have it and it can just be one of those things?

I can get a mechanic that has a Custom engine shop to come out for 50 bux to diagnose the problem. He told me he is really good at it over the phone? Should i spend the 50 dollars?

Yes i did use a stock timing chain and after installing it I was curious if it had a little to much slack in it

 

valve cover

Hi,take that chevy valve cover,and make 1 long cut(lengthwise)then a shorter cut on both ends,then bend up the uncut part of the cover,and it will catch MOST of the oil when youre adjusting the valves.have fun.

 

I would adj. the valves 1st if you had already decided to do it, and see what your results are before calling the mechanic. IMO. You may get rid of your knock.
As far as the growling noise, did you notice if the distributor seemed to sit flush with the manifold before you tighten down the distributor hold-down clamp? It should have come with a gasket. A good check is to try to install it without the gasket 1st to see if it will set flush with the manifold. If it wasn't quite flush you need a/some spacers to lift it up a bit so that its not pushing down on the oil pump drive shaft/oil pump assy.
Was the 305 it came out of a roller cam engine? If it was it was probably the right type of gear, but I think you should always install a new gear with a new cam.IMO
By the way, I'm no pro mechanic. Just a shade tree.
FWIW
ssmonty

 

I would adj. the valves 1st if you had already decided to do it, and see what your results are before calling the mechanic. IMO. You may get rid of your knock.
As far as the growling noise, did you notice if the distributor seemed to sit flush with the manifold before you tighten down the distributor hold-down clamp? It should have come with a gasket. A good check is to try to install it without the gasket 1st to see if it will set flush with the manifold. If it wasn't quite flush you need a/some spacers to lift it up a bit so that its not pushing down on the oil pump drive shaft/oil pump assy.
Was the 305 it came out of a roller cam engine? If it was it was probably the right type of gear, but I think you should always install a new gear with a new cam.IMO
By the way, I'm no pro mechanic. Just a shade tree.
FWIW
ssmonty

Shoot I appreciate whatever you have to suggest Shade tree or ASE certified

The 305 had a flat tappet cam. I just pulled it and took the gasket off and it sits pretty flush with intake , I may put 2 gaskets next time to have some clearance.

Check out this Distributor gear it looks pretty bad and when I take the rotor and move it back and forth there is considerable clanking going on down there! I would say by guess it will move back and forth 3/16 or so.

I happen to have a brass distributor gear for this motor but I thought brass was for billet Cam?

here is a pic

 

Here is my take on the vortec, Vortec motors use a different timing chain then the older motors, so a standard double roller won't fit (http://www.fullsizechevy.com/forum/general-discussion/technical-maintenance/327568-correct-timing-chain-set-96-350-vortec.html} may rub on block or cover. Also are you running a roller cam? Vortec were all roller cam, so if you went flat tappet, did you change push rods or check length? If you didn't and just adjusted valves normally, the angle of push rods will rub the hole in the heads. First mod or vortecs is drill out to 3/8 push rod holes. Also check all the rocker studs, lay a straight edge across, check if any are starting to pull out.

As some noted about cam walk, did the cam and lifter bore get checked? a cam thats off, will limit oil to bearings. Also your compression, back off 1 turn on the rockers and retest, if they come up in number then your bottom end is probably good.

I built a 383 vortec, broke studs, the stock 3/8 studs are weak, ran into the timing chain issue. Also the dist gear was designed for the cam, roller cams are different. The vortec marine had a different distrubuter with gear, so you might have make changes. As long as the motor is not reverse rotation, get a good marine/rv cam, lifters and push rod checker. you will get it going.

 

If you got it to sit flush without a gasket, you should be fine using just one, and it will hold its adjustment better.
With 3/16" of play I would think your timing would be very erratic. Besides it is supposed to be a melonized(hardened) gear for a roller cam. The cam is steel vrs cast iron for flat tappet. Not necessarily billet. I wouldn't use the bronze gear unless it was a billet. They don't last and end up in the oil pan as shavings.
Pace Performance sells GM melonized gears PN 10456413 for old style HEI distributors with .491" shafts for $36.95. Its a slip fit after you remove the roll pin with a punch. If you order one from them you might also ask for a new roll pin to install it. While your at it check the end play(feeler gauge between the gear and the distributor body bushing.) I'm not sure on the spec. I want to say .015"-.020". Maybe someone else will chime in? Hopefully its not too late to put on a new gear to save the cam dizzy drive gear? Should be ok.
You didn't say if you were using polylocks on the rocker arm studs(allen set screws in the middle)? Probably are. I should have mentioned that when I adjust them, I will get the outer body almost where it needs to be, tighten the set screw, then turn both at the same time, just a little, to make it stay tight. I've had them loosen up by themselves too many times unless I do it like that.
FWIW
ssmonty

 

If you got it to sit flush without a gasket, you should be fine using just one, and it will hold its adjustment better.
With 3/16" of play I would think your timing would be very erratic. Besides it is supposed to be a melonized(hardened) gear for a roller cam. The cam is steel vrs cast iron for flat tappet. Not necessarily billet. I wouldn't use the bronze gear unless it was a billet. They don't last and end up in the oil pan as shavings.
Pace Performance sells GM melonized gears PN 10456413 for old style HEI distributors with .491" shafts for $36.95. Its a slip fit after you remove the roll pin with a punch. If you order one from them you might also ask for a new roll pin to install it. While your at it check the end play(feeler gauge between the gear and the distributor body bushing.) I'm not sure on the spec. I want to say .015"-.020". Maybe someone else will chime in? Hopefully its not too late to put on a new gear to save the cam dizzy drive gear? Should be ok.
You didn't say if you were using polylocks on the rocker arm studs(allen set screws in the middle)? Probably are. I should have mentioned that when I adjust them, I will get the outer body almost where it needs to be, tighten the set screw, then turn both at the same time, just a little, to make it stay tight. I've had them loosen up by themselves too many times unless I do it like that.
FWIW
ssmonty

The nuts to adjust rockers are standard lock nuts

I think i need to replace the timing set. after I changed the Dist. gear and started the motor I noticed the knock seemed better ( i made a video) but I also noticed the motor was more responsive. I checked timing with a light and it was advanced quite a bit when i set it at about 8 BTDC is was sluggish again
I am wondering if the timing chain stretched when the .550 lift cam was binding against the valve seals. and also making some noise

After changing dist gear

 

Very possible the Chain stretched. It's suprising that none of the Pushrods were bent.
The RamJet Cam is Billet Steel which is much softer than Cast Iron & uses the Melonized, Composite/Plastic or Brass distributor gear.
Melonizing is kind of like a soft Powder coating over a hardened steel gear.
Brass gear isn't good for a street engine, it wears too quickly and needs to be changed frequently.
Flat Tappet Cast Iron cams use a hardened steel gear which is equal in hardness to the Cam.

 

Very possible the Chain stretched. It's suprising that none of the Pushrods were bent.
The RamJet Cam is Billet Steel which is much softer than Cast Iron & uses the Melonized, Composite/Plastic or Brass distributor gear.
Melonizing is kind of like a soft Powder coating over a hardened steel gear.
Brass gear isn't good for a street engine, it wears too quickly and needs to be changed frequently.
Flat Tappet Cast Iron cams use a hardened steel gear which is equal in hardness to the Cam.

Thanks for the clarification!!

 

Small update - it seems to me the knock is kinda going away?? My gut feeling is a lifter?

But I did change the oil today and there was not any metal in the oil nor on the magnetic oil plug So I am thinking that is pretty good news.

For some reason my timing is retarded when I set it at 8 BTDC , It runs alot better and seems to knock less when I advance the timing way past what it should be So I am going to pull the cover and look at the chain and gears and then put a new timing set on it.

Just curious to remove crank gear Do I need a puller?

And 1 more I read about cutting the inside ledge off plastic timing cover so it is easier to put it back in between the oil pan gasket. Is this a good Idea?

Stephen

 

Sure sounds allot better than it did before!!!
I didn't hear the growling noise on the new vid.
Looks like the vacuum gauge was steady too, but that may have been because you had the idle up? Did you adjust the valves? Sounds good to me.
If you didn't, and just changing the gear made that much of a difference I apologize for leading you in the wrong direction. If you loosened a rocker I hope you could see(hear) why I suggested adjusting the valves.
Part of it could have been the cam slamming back and forth into the retainer plate when the cam and dizzy gear would dig into each other?
Does the new gear give you the same back and forth slop(3/16")? Does the dizzy shaft move up & down much? If the shaft doesn't move up&down the slop is either the play in the cam/dizzy gear or the chain or combination of the two if I'm not mistaken.
You might be able to put a wrench on the crank bolt and turn it back and forth a little while watching/holding the dizzy advance assy to help identify if its the chain or the gears are sloppy?
FWIW
ssmonty

 

I just saw your update and yes you will need a puller to get the gear off. It would be a good idea IMOto get an installer like a balancer installer and use some type of pipe extension(pvc) to put the new one on. I personally don't like hammering against a thrust bearing.
You might not need to if the chain is still good. You shouldn't be able to flex it the way a belt tensioner would. Maybe just barely. I mean barely. Check to see that the cam won't move forwards or back into the block with the gear on before you remove it. I wish I could tell you the spec for cam end play, but I don't know it. Anybody?
BTW whats way more advanced. 10-12 degrees should be ok for starters. 32-34 max total advance on vortec heads w/out vacuum advance. Then adjust your carb idle mixture screws for highest vacuum. Re-adjust idle speed screw. Good luck!
FWIW
ssmonty

 

Here is a really good video of the motor at very low rpm.

The knock is pretty clear lol

Low RPM knock

 

I just saw your update and yes you will need a puller to get the gear off. It would be a good idea IMOto get an installer like a balancer installer and use some type of pipe extension(pvc) to put the new one on. I personally don't like hammering against a thrust bearing.
You might not need to if the chain is still good. You shouldn't be able to flex it the way a belt tensioner would. Maybe just barely. I mean barely. Check to see that the cam won't move forwards or back into the block with the gear on before you remove it. I wish I could tell you the spec for cam end play, but I don't know it. Anybody?
BTW whats way more advanced. 10-12 degrees should be ok for starters. 32-34 max total advance on vortec heads w/out vacuum advance. Then adjust your carb idle mixture screws for highest vacuum. Re-adjust idle speed screw. Good luck!
FWIW
ssmonty

Thanks for all your time I guess I am going to pull the engine and tear it down ;(

 

I just got off work and saw your post about tearing it down. Bummer, but thats what I would do if it were mine. At least pull the pan and check the rods.
I heard the last video late last night, but didn't want to say what came to my mind as I'm no pro and I didn't want you to pull the pan for nothing in case I was wrong. I was hoping someone else would say something, and I figured you had enough sense not to get on it.
I was going to say something today if no one else did, but it looks like you beat me to it.
Good Luck!
ssmonty

 

Well I wanted to check my valve timing one more time before I pulled it and after doing some research I think I may have found a problem. I am pretty sure when I put the 2 dots together I was on TDC #1 compression stroke. I read that the 2 dots are lined up when on #1 Exhaust Stroke? and #6 is on intake stroke and ready to fire. Then for ignition turn the motor till #1 tdc compression stroke and stab the distributor pointing to number 1.

So now I have it right, just curious if I damaged engine?

made another video haha Engine seems alot better!!

Engine after camshaft rotated 180

 

I believe what your referring to is having the distributor installed 180* out. If it was, it wouldn't run at all. Maybe get some fire shoot out the carb, but you didn't hurt it by having it installed backwards so to speak.
I couldn't help but notice that the chain had allot of slop at about 1:24 in the video. Couldn't see much as it was too dark, but then you could really see it wrap up-behind the crank gear something awful!
I also couldn't help but hear that knocking sound. Try not to rev it up until you find out what it is and fix it!!!
Get it to idle up a little higher than what you have now, and pull a plug wire while its running, and listen for the sound to change for a sec or two before replacing it. Use some insulated pliers or thick rubber gloves and a set of pliers while leaving your other hand in your pocket.(just don't let any part of your body touch engine electrical ground) If no change in sound, go to the next plug and so on. It may be easier to pull them from the distributor cap than the plug itself. If you find one that makes a difference, you know where to start looking.
I'd definitely put a new timing chain set on it regardless.IMO
Forgive me if I sound like I'm talking to a child at times, but sometimes if you don't, and assume someone knows what your talking about, things can get really messed up. Good Luck!
FWIW
ssmonty

 

I believe what your referring to is having the distributor installed 180* out. If it was, it wouldn't run at all. Maybe get some fire shoot out the carb, but you didn't hurt it by having it installed backwards so to speak.
I couldn't help but notice that the chain had allot of slop at about 1:24 in the video. Couldn't see much as it was too dark, but then you could really see it wrap up-behind the crank gear something awful!
I also couldn't help but hear that knocking sound. Try not to rev it up until you find out what it is and fix it!!!
Get it to idle up a little higher than what you have now, and pull a plug wire while its running, and listen for the sound to change for a sec or two before replacing it. Use some insulated pliers or thick rubber gloves and a set of pliers while leaving your other hand in your pocket.(just don't let any part of your body touch engine electrical ground) If no change in sound, go to the next plug and so on. It may be easier to pull them from the distributor cap than the plug itself. If you find one that makes a difference, you know where to start looking.
I'd definitely put a new timing chain set on it regardless.IMO
Forgive me if I sound like I'm talking to a child at times, but sometimes if you don't, and assume someone knows what your talking about, things can get really messed up. Good Luck!
FWIW
ssmonty

I Found #1 Rod bearing shot. This Boat has been a nightmare.

 

I believe what your referring to is having the distributor installed 180* out. If it was, it wouldn't run at all. Maybe get some fire shoot out the carb, but you didn't hurt it by having it installed backwards so to speak.
I couldn't help but notice that the chain had allot of slop at about 1:24 in the video. Couldn't see much as it was too dark, but then you could really see it wrap up-behind the crank gear something awful!
I also couldn't help but hear that knocking sound. Try not to rev it up until you find out what it is and fix it!!!
Get it to idle up a little higher than what you have now, and pull a plug wire while its running, and listen for the sound to change for a sec or two before replacing it. Use some insulated pliers or thick rubber gloves and a set of pliers while leaving your other hand in your pocket.(just don't let any part of your body touch engine electrical ground) If no change in sound, go to the next plug and so on. It may be easier to pull them from the distributor cap than the plug itself. If you find one that makes a difference, you know where to start looking.
I'd definitely put a new timing chain set on it regardless.IMO
Forgive me if I sound like I'm talking to a child at times, but sometimes if you don't, and assume someone knows what your talking about, things can get really messed up. Good Luck!
FWIW
ssmonty

Appreciate the help and wanted to share a Video with the motor actually running like it should!

Ron Paul 2012

my 1st Hotrod