'69 427 Bent Push Rod
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
I post the rotator pics for info.
AFAIK ... OP is still trying to find what went wrong and has Not found root cause .... and AFAIK ... OP has not begun to "repair" anything yet. Hope Not as Unwise to start buying parts & pieces before you even know all that's truly wrong.
I have yet to see pics of valve train ASSEMBLED. Lotsa bits & pieces.
From beginning I've leaned toward coil bind or retainer crash as root cause ... but have yet to see complete coil bind evidence. Seems OP may go further into that today; Maybe we're close. But I'm not convinced ... yet.
AFAIK ... OP is still trying to find what went wrong and has Not found root cause .... and AFAIK ... OP has not begun to "repair" anything yet. Hope Not as Unwise to start buying parts & pieces before you even know all that's truly wrong.
I have yet to see pics of valve train ASSEMBLED. Lotsa bits & pieces.
From beginning I've leaned toward coil bind or retainer crash as root cause ... but have yet to see complete coil bind evidence. Seems OP may go further into that today; Maybe we're close. But I'm not convinced ... yet.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
I think he found it with the .020 number at full lift....I think he needs springs with a smaller coil....more room. If the retainer did crash it would destroy the valve seal so I am ruling that out an his numbers support that.
I am also ruling out piston to valve with a .500 lift cam.....but even as I am ruling this stuff out.....it still needs to be checked.
Jebby
I am also ruling out piston to valve with a .500 lift cam.....but even as I am ruling this stuff out.....it still needs to be checked.
Jebby
Thread Starter
Racer
Joined: Apr 2013
Posts: 302
Likes: 16
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Thread Starter
Racer
Joined: Apr 2013
Posts: 302
Likes: 16
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Yeah...the collision caused damage. Pull the heads......disassemble and purchase matched components. A call to Comp will help.....
Inspect the seats for damage.....you may get by putting new valves in if they lap out nicely....
Jebby
Inspect the seats for damage.....you may get by putting new valves in if they lap out nicely....
Jebby
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
I think he found it with the .020 number at full lift....I think he needs springs with a smaller coil....more room. If the retainer did crash it would destroy the valve seal so I am ruling that out an his numbers support that.
I am also ruling out piston to valve with a .500 lift cam.....but even as I am ruling this stuff out.....it still needs to be checked.
Jebby
I am also ruling out piston to valve with a .500 lift cam.....but even as I am ruling this stuff out.....it still needs to be checked.
Jebby
But I have yet to see what is root cause. Is that 0.020" sum total? If so; coil bind IS a cause but may not be only culprit. In the end, looking like there may be a banner day at XCH.
I'd like to know the origin of the bad tip on intake #1. And ...was it assembled (freshened) that way?
IIRC, comp can rebuild/replace their rocker tips. Suggest also inspect rocker *****-cups for damage, discolor, galling, spalling etc.
Thread Starter
Racer
Joined: Apr 2013
Posts: 302
Likes: 16
I do Not disagree.
But I have yet to see what is root cause. Is that 0.020" sum total? If so; coil bind IS a cause but may not be only culprit. In the end, looking like there may be a banner day at XCH.
I'd like to know the origin of the bad tip on intake #1. And ...was it assembled (freshened) that way?
IIRC, comp can rebuild/replace their rocker tips. Suggest also inspect rocker *****-cups for damage, discolor, galling, spalling etc.
But I have yet to see what is root cause. Is that 0.020" sum total? If so; coil bind IS a cause but may not be only culprit. In the end, looking like there may be a banner day at XCH.
I'd like to know the origin of the bad tip on intake #1. And ...was it assembled (freshened) that way?
IIRC, comp can rebuild/replace their rocker tips. Suggest also inspect rocker *****-cups for damage, discolor, galling, spalling etc.
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Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Virtually every bbc head has umbrellas on it these days, including OE crate 502 461 hp engines. That is a crap load of bullets and very few engine builders left. Personally I leave exhaust seals out. OP has a bit over .6 clearance with seal, shims and all. Valve guides. Yes they are pressed in. But they are pressed in blank and machined after install. So the valve is not in the canter of the guide. You fix that guide correctly with an insert like any other iron head.
Thread Starter
Racer
Joined: Apr 2013
Posts: 302
Likes: 16
Pull the heads??
I still don't know if the lifters are solid or hydraulic.
I'm pissed off!
This is getting deeper and deeper!
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
hydraulic lifter you can push the center of it down. I worked on heads in a machine shop early 70s as my main job and assembled engines. Do yourself a favor pull the heads off let a good machine shop look them over. I assume when you pulled the lifters you know which one goes with with each lobe and your cam lobes look good to you. On another point im 66 built engines age 16 before that motorcycles. I live less then 35 miles north of arlington texas and reher and morison. Im going diwn there ask them about putting umbrealla valve seals on my heads. After they stop rolling around on the floor laughing maybe if lucky they cant throw my 250 lb *** out the door.
Last edited by Little Mouse; Mar 14, 2019 at 08:05 PM.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
The lifters are hydraulic. You're no deeper than you were Going anyway. You need to to get down to where you were removing the valve Springs. https://www.jegs.com/i/COMP-Cams/249/911-16/10002/-1. These will work well with existing retainers and keepers. https://www.ebay.com/p/Engine-Valve-...90400bfff1f81b. These are everywhere. Make sure you get 3/8 stem and watch seal O/D to spring I/D. Oh yeah; pushrods. Geometry is good get the same length.
Burning Brakes
Joined: Jul 2016
Posts: 767
Likes: 74
From: Blaine MN
Do the Jebby, me and others suggestion and fully degree the cam, yes it'll be a pain in the back but then you know where you are at, you need new PR's anyway (yes you could straighten them first and drive again, but being bent in the first place points to other issues), if you go through the degree process you'll verify correct pushrod length and a warm fuzzy about the cam timing being correct.
The other choice is jump in and pull the Heads, then you'll have a chance to make sure it's all good.
I'd push towards the first option, you'll need the tools anyway if the problem remains after pushrods are fixed/replced.
Last edited by suprspooky; Mar 14, 2019 at 08:21 PM.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Pull the heads off let the machine shop dissasemble them, check them for cracks betwen the valves, they will put a machinist strait edge across them. Look at your seats and valves and check your guides out. Small valve heads both sbc and bbc were pretty good about not cracking between the seats the big valve heads were. A little money spent up front is a lot better then doing the job over. Then you will be really pissed
Last edited by Little Mouse; Mar 14, 2019 at 08:38 PM.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Factory bbc used a 1.8 install spring height compared to 1.7 sbc. If you have only .505 total lift and you know that for sure. You have zero problem with retainer to guide, zero problem with spring coil bind, zero problem with valve to piston clearence. Something else caused your problem. Pull the friggen heads off.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
1972 my farther bought a new 429 ford grand marqee. At 90 thousand miles i helped him pull the pan off it. Pan was full of rubber pieces including in the pickup screen. Every valve guide all 16 of the rubber umbrella valve seals had desintegraded from the engine oil heat over time. Not one of them was still intact. Zero as in nada.
Last edited by Little Mouse; Mar 14, 2019 at 09:01 PM.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
1972 my farther bought a new 429 ford grand marque. At 90 thousand miles i helped him pull the pan off it. Pan was full of rubber pieces including in the pickup screen. Every valve guide all 16 of the rubber umbrella valve seals had desintegraded from the engine oil heat over time. Not one of them was still intact.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
if mine i would pull the heads. but i have a seat machine and a stack of head gaskets. have you done compression or leak down test yet? take heads to the shop and it is seats and guides and might as well put in 16 valves. that'll be 800 buck please. mebbe 1200. 1400 if they machine the guides for positive seals. are you trying to get into the 11's or are you driving around on nice weekend days? you can do leakdown without rockers and pushrods. you gonna spend 1400 on heads, might as well spend 2k on new aluminum heads. hell, 496 rotating assy. you need the pushrods-100 bucks, springs-100, rotator eliminators-30, seals-10 to 40 and a rocker or 2-20 to 50 whether you pull the heads or not. put it together. run it.
Last edited by derekderek; Mar 14, 2019 at 09:10 PM.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Lol. I know he has asked around for a non crooked machine shop has recomendations for one.need to find out what caused it or assume previous owner idiot driver. Already know he was an idiot had unbrella valve seals. Lol. Again there is zero as in nada with .505 lift cam in bbc of ratainer to guide, coil bind or valve ro piston. But then something bent the pushrods.
Last edited by Little Mouse; Mar 14, 2019 at 09:26 PM.