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Bent / broken push rods #1175147 02/09/12 01:49 AM 02/09/12 01:49 AM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	I'm working on a new 440 that bent the intake push rods just after break in and I'm trying to figure out why. I made a push rod length checker and these are the numbers I came up with : Stock push rod = 9.292 Rod checker results from lifter cup to rocker cup : intake = 9.203 exhaust = 9.210 Is this enough to cause all of my intake push rods to bend / break? were should I look now ? I checked the pistons with a bore scope through the spark plug hole and I don't have any damage on my pistons at all so the valves never touched them.

Re: Bent / broken push rods [Re: 73rrak] #1175148 02/09/12 05:04 AM 02/09/12 05:04 AM
Joined: Aug 2003 Posts: 12,291 Kent, Wa 340SHORTY Truck Nut
340SHORTY Truck Nut Joined: Aug 2003 Posts: 12,291 Kent, Wa	if thats the case,,, how/what bent them??? Wht did you use/get unequal lenght PRs? HEMIs are the only Mopar engine that I know of that has unequal length PRs.. I am truckless..

Re: Bent / broken push rods [Re: 340SHORTY] #1175149 02/09/12 08:50 AM 02/09/12 08:50 AM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	I re used the push rods that were in the motor. The motor was out of a 77 motor home with 48,000 miles on it and from the looks of it it had never been opened before I opened it. Although I never heard the motor run before I took it apart it was super clean inside and in completely stock form. I don't know if the push rods were all the same size and now it will be impossible to tell being that all of the intake rods are bent. I didn't mark them or separate them when I took them of the motor so the chances of getting all long ones on the intake only are pretty slim. There has got to be something else wrong in this motor.

Re: Bent / broken push rods [Re: 73rrak] #1175150 02/09/12 10:42 AM 02/09/12 10:42 AM
Joined: Aug 2010 Posts: 343 S.E.Mich D drew72 enthusiast
drew72 enthusiast D Joined: Aug 2010 Posts: 343 S.E.Mich	Coil Bind

Re: Bent / broken push rods [Re: drew72] #1175151 02/09/12 01:57 PM 02/09/12 01:57 PM
Joined: Jan 2003 Posts: 16,376 D dogdays I Live Here
dogdays I Live Here D Joined: Jan 2003 Posts: 16,376	MODS!!!!! This guy has two open threads on this same topic in this forum and one in the race forum. I'm getting tired of opening a thread and reading the same old whining and guesswork answers. To the OP: Take the doggone heads off, but before you do, check valve to piston clearance using a light spring and degree wheel. Get V/P measurement at every 5 degrees from 20 degrees BTDC to 20 ATDC. While you've got the spring off measure its compressed height. Also check the valve stem seal to retainer clearance. Measure the actual pushrod diameter between an end and the bend. If they all check out it's valve guides. Between now and the time you get that done don't start another thread about the same thing. R.

Re: Bent / broken push rods [Re: dogdays] #1175152 02/09/12 02:57 PM 02/09/12 02:57 PM
Joined: Aug 2003 Posts: 8,716 Baltimore/Denver 64Post master
64Post master Joined: Aug 2003 Posts: 8,716 Baltimore/Denver	Quote: MODS!!!!! This guy has two open threads on this same topic in this forum and one in the race forum. I'm getting tired of opening a thread and reading the same old whining and guesswork answers. To the OP: Take the doggone heads off, but before you do, check valve to piston clearance using a light spring and degree wheel. Get V/P measurement at every 5 degrees from 20 degrees BTDC to 20 ATDC. While you've got the spring off measure its compressed height. Also check the valve stem seal to retainer clearance. Measure the actual pushrod diameter between an end and the bend. If they all check out it's valve guides. Between now and the time you get that done don't start another thread about the same thing. R. Never mind... Last edited by 64Post; 02/09/12 03:00 PM.

Re: Bent / broken push rods [Re: dogdays] #1175153 02/09/12 03:39 PM 02/09/12 03:39 PM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	Dogdays.... I don't have a post in the race section I've never even been to the race section. I don't have 3 threads going on this same subject. One is for a carb issue that thread lead into the all of my intake push rods are bent one. The 3rd one I have going is me trying to find out what the stock rocker ratio is so I can eliminate that as a possible cause of the problem. I didn't mean to upset anybody I was just trying to solve a problem and have people read 2 pages of posts to get to a question on another part of the problem although it was in the same category. Drew. and whoever else guessed coil bind I think you might have it. I have a spring off and the valve seal looks fine but I can see area where the spring hammered into the spring perch. I'm working with the machine shop that did the head work I will let you know how that goes.

Re: Bent / broken push rods [Re: 73rrak] #1175154 02/09/12 04:36 PM 02/09/12 04:36 PM
Joined: Jan 2003 Posts: 4,722 Moved to N.E. Tennessee GomangoCuda master
GomangoCuda master Joined: Jan 2003 Posts: 4,722 Moved to N.E. Tennessee	If it is coil bind and the shop knew the cam specs then let them fix it(if they know how) and never go back. NEVER. In theory, there is no difference between theory and practice. In practice, there is.

Re: Bent / broken push rods [Re: 73rrak] #1175155 02/09/12 04:39 PM 02/09/12 04:39 PM
Joined: Mar 2003 Posts: 4,848 Memphis HemiRick master
HemiRick master Joined: Mar 2003 Posts: 4,848 Memphis	Was the gas it ran on new? Old gas will leave tar in the intake tract and when the engine cools it cements the intake valves in place. When you crank the engine again the pushrods bend. Take care, Rick 68 Coronet R/T 440 & 68 Charger 528 Hemi,and 5 Challengers! 6 cyl, 318, 360, 383, 451

Re: Bent / broken push rods [Re: GomangoCuda] #1175156 02/09/12 05:08 PM 02/09/12 05:08 PM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	It looks like it was coil bind I only have .375 travel on the valve. I found an extra spring that was installed that the machine shop says is not supposed to be there. I have the outside spring the damper and a spring inside the damper. I'm taking the extra spring out and checking it again. I will let you guys know what I find.

Re: Bent / broken push rods [Re: 73rrak] #1175157 02/09/12 05:14 PM 02/09/12 05:14 PM
Joined: Jan 2003 Posts: 75,015 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 75,015 U.S.S.A.	Quote: It looks like it was coil bind I only have .375 travel on the valve. I found an extra spring that was installed that the machine shop says is not supposed to be there. I have the outside spring the damper and a spring inside the damper. I'm taking the extra spring out and checking it again. I will let you guys know what I find. How do they know it's not supposed to be there , the Hughes spring may be a double spring and if it is the spring seat on a factory head is not cut to accept that type of spring arrangement .... Are the heads off yet ?

Re: Bent / broken push rods [Re: JohnRR] #1175158 02/09/12 05:40 PM 02/09/12 05:40 PM
Joined: Jan 2003 Posts: 32,931 Grand Prairie,Texas stumpy I Win
stumpy I Win Joined: Jan 2003 Posts: 32,931 Grand Prairie,Texas	Pull the heads and check things correctly. Even in the driveway with hand tools it's only a two hour job.

Re: Bent / broken push rods [Re: JohnRR] #1175159 02/09/12 05:41 PM 02/09/12 05:41 PM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	No the heads are still on and they are staying on. The extra spring was the problem for some reason Hughes shipped them with the extra spring and Hughes says it's not supposed to be there. The machine shop just installed them the way they received them. Yes they should have checked them but right now I'm just happy to have the problem solved without having to take this thing back apart. Now I just need to get the camera out of the cylinder and maybe I can drive this piece of crap.

Re: Bent / broken push rods [Re: 73rrak] #1175160 02/09/12 05:44 PM 02/09/12 05:44 PM
Joined: Jan 2003 Posts: 75,015 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 75,015 U.S.S.A.	Quote: No the heads are still on and they are staying on. The extra spring was the problem for some reason Hughes shipped them with the extra spring and Hughes says it's not supposed to be there. The machine shop just installed them the way they received them. Yes they should have checked them but right now I'm just happy to have the problem solved without having to take this thing back apart. Now I just need to get the camera out of the cylinder and maybe I can drive this piece of crap. now that you have said that you will be pulling that head to get the camera out ... good luck ...

Re: Bent / broken push rods [Re: JohnRR] #1175161 02/09/12 06:01 PM 02/09/12 06:01 PM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	I gave up worrying about saying bad things about this car months ago. It can't get back at me any more than it already has...... hhahahahha Thank you everybody for all of the help

Re: Bent / broken push rods [Re: JohnRR] #1175162 02/09/12 06:10 PM 02/09/12 06:10 PM
Joined: Aug 2003 Posts: 8,716 Baltimore/Denver 64Post master
64Post master Joined: Aug 2003 Posts: 8,716 Baltimore/Denver	Quote: Quote: No the heads are still on and they are staying on. The extra spring was the problem for some reason Hughes shipped them with the extra spring and Hughes says it's not supposed to be there. The machine shop just installed them the way they received them. Yes they should have checked them but right now I'm just happy to have the problem solved without having to take this thing back apart. Now I just need to get the camera out of the cylinder and maybe I can drive this piece of crap. now that you have said that you will be pulling that head to get the camera out ... good luck ... If it went in through the plug hole why wouldn't it come out the same way?

Re: Bent / broken push rods [Re: 64Post] #1175163 02/09/12 07:14 PM 02/09/12 07:14 PM
Joined: Jan 2003 Posts: 75,015 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 75,015 U.S.S.A.	Quote: Quote: Quote: No the heads are still on and they are staying on. The extra spring was the problem for some reason Hughes shipped them with the extra spring and Hughes says it's not supposed to be there. The machine shop just installed them the way they received them. Yes they should have checked them but right now I'm just happy to have the problem solved without having to take this thing back apart. Now I just need to get the camera out of the cylinder and maybe I can drive this piece of crap. now that you have said that you will be pulling that head to get the camera out ... good luck ... If it went in through the plug hole why wouldn't it come out the same way? The issue will be grabbing it to get it out thru the plug hole, I'm guessing it wasn't much smaller than the plug hole. If it were me I'd almost be tempted to pull off the intake , pull the intkae valve spring , make sure the exhaust is closed , put the plug back in , lower the piston some and open the intake valve to the point that the retainer with locks is sitting on top of the guide and use a shop vac to try to suck it out the intake port ...

Re: Bent / broken push rods [Re: JohnRR] #1175164 02/09/12 07:36 PM 02/09/12 07:36 PM
Joined: May 2003 Posts: 6,562 Downtown Roebuck Ont Twostick Still wishing...
Twostick Still wishing... Joined: May 2003 Posts: 6,562 Downtown Roebuck Ont	Kevin

Re: Bent / broken push rods [Re: Twostick] #1175165 02/09/12 08:48 PM 02/09/12 08:48 PM
Joined: Apr 2007 Posts: 905 SD Z zrxkawboy super stock
zrxkawboy super stock Z Joined: Apr 2007 Posts: 905 SD	So what did all of this do to the new cam? It's Swifty! Swifty, you toad sucker!

Re: Bent / broken push rods [Re: zrxkawboy] #1175166 02/09/12 09:23 PM 02/09/12 09:23 PM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	Dude that motor needs to be torn down, sorry. The heads have to come off, the cam needs to come out and the pan needs to be dropped. No getting around it. You could have bent the valves, wiped the cam and damaged the pistons. You can't see much w/ those little "scope" cameras. It would stink to heck to put it all togther and have the same thing happen at fire up or to find out the cam was wiped. I've been where you are I had 200 miles on a brand new engine when it dropped a valve(I/we think the cam walked) At least you can fix yours. I ruined 2 cylinders, 2 pistons, filled the crank case w/ water and toasted 2 valve seats on a super nice set of iron heads. Grab a 12 pack and get rolling. [IMG]http://i66.tinypic.com/pui5j.jpg[/IMG] Coming soon!!!!

Re: Bent / broken push rods [Re: 64Post] #1175167 02/09/12 09:37 PM 02/09/12 09:37 PM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	The angle of the piston keeps the camera on the cylinder wall just below the plug hole but perpendicular to the hole. The camera is 9 MM X about 1" to maybe 1-1/2 so the only way to grab it is by the ends to take it out but I can't grab the ends because it keeps rolling to the bottom of the plug hole. I tried jacking on side of the car up to relieve some of the angle of the piston it helped but not enough. I'll get it out and it should be easier now that the valve train problem is out of my head.

Re: Bent / broken push rods [Re: JohnRR] #1175168 02/09/12 09:41 PM 02/09/12 09:41 PM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	Quote: Quote: Quote: Quote: No the heads are still on and they are staying on. The extra spring was the problem for some reason Hughes shipped them with the extra spring and Hughes says it's not supposed to be there. The machine shop just installed them the way they received them. Yes they should have checked them but right now I'm just happy to have the problem solved without having to take this thing back apart. Now I just need to get the camera out of the cylinder and maybe I can drive this piece of crap. now that you have said that you will be pulling that head to get the camera out ... good luck ... If it went in through the plug hole why wouldn't it come out the same way? The issue will be grabbing it to get it make out thru the plug hole, I'm guessing it wasn't much smaller than the plug hole. If it were me I'd almost be tempted to pull off the intake , pull the intkae valve spring , make sure the exhaust is closed , put the plug back in , lower the piston some and open the intake valve to the point that the retainer with locks is sitting on top of the guide and use a shop vac to try to suck it out the intake port ... I like this idea I'm gonna try it ....... Thanks

Re: Bent / broken push rods [Re: 73rrak] #1175169 02/09/12 10:03 PM 02/09/12 10:03 PM
Joined: Jan 2003 Posts: 75,015 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 75,015 U.S.S.A.	Quote: Quote: Quote: Quote: Quote: No the heads are still on and they are staying on. The extra spring was the problem for some reason Hughes shipped them with the extra spring and Hughes says it's not supposed to be there. The machine shop just installed them the way they received them. Yes they should have checked them but right now I'm just happy to have the problem solved without having to take this thing back apart. Now I just need to get the camera out of the cylinder and maybe I can drive this piece of crap. now that you have said that you will be pulling that head to get the camera out ... good luck ... If it went in through the plug hole why wouldn't it come out the same way? The issue will be grabbing it to get it make out thru the plug hole, I'm guessing it wasn't much smaller than the plug hole. If it were me I'd almost be tempted to pull off the intake , pull the intkae valve spring , make sure the exhaust is closed , put the plug back in , lower the piston some and open the intake valve to the point that the retainer with locks is sitting on top of the guide and use a shop vac to try to suck it out the intake port ... I like this idea I'm gonna try it ....... Thanks Actually after reading your other post it sounds like it's on the plug hole ... I assumed it fell completely into the cylinder ... put the vacuum on the plug hole first , release the valve train so the valves are closed. When you get it back together , with the valve train off do a leak down test on all the cylinders , this will tell you if you have bent valves .

Re: Bent / broken push rods [Re: JohnRR] #1175170 02/09/12 10:26 PM 02/09/12 10:26 PM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	I'll be able to tell tonight if it has leaking valves. I'm using air to hold the valves up while I take the extra spring out. So far I can hear air going past the rings but none from the valves. I have 6 more to go so the car still has six more chances to show it's evil side .... Hhahahhaha The camera is "in" the cylinder but with the piston up all the way it sits just below the spark plug hole against the cylinder wall. I wish it was just in the spark plug hole it would be out by now.

Re: Bent / broken push rods [Re: 73rrak] #1175171 02/09/12 10:28 PM 02/09/12 10:28 PM
Joined: Jan 2008 Posts: 3,886 Lost and Spaced B bboogieart master
bboogieart master B Joined: Jan 2008 Posts: 3,886 Lost and Spaced	I don't mean to be a jack a$$ but I think I would have had that head off by now. I have mechanical Aptitude. I can screw up anything.

Re: Bent / broken push rods [Re: bboogieart] #1175172 02/09/12 10:34 PM 02/09/12 10:34 PM
Joined: May 2011 Posts: 340 Alaska 7 73rrak OP enthusiast
73rrak OP enthusiast 7 Joined: May 2011 Posts: 340 Alaska	I hope it doesn't come to that but if it does I'll take the heads off. I have a new camera coming it should be here tomorrow this one has a hook attachment with it that goes in front of the lens I hope that will work better.

Re: Bent / broken push rods [Re: bboogieart] #1175173 02/10/12 12:19 AM 02/10/12 12:19 AM
Joined: Jan 2003 Posts: 3,719 Space Station #5 471Magnum master
471Magnum master Joined: Jan 2003 Posts: 3,719 Space Station #5	Quote: I don't mean to be a jack a$$ but I think I would have had that head off by now. No kidding. Only takes a couple hours to pull a head. -Jim I can fix it... my old man is a television repairman. He's got the ultimate set of tools... I can fix it. Currently Mopar-less

Re: Bent / broken push rods [Re: 471Magnum] #1175174 02/10/12 11:55 AM 02/10/12 11:55 AM
Joined: Jul 2008 Posts: 394 md W wicked enthusiast
wicked enthusiast W Joined: Jul 2008 Posts: 394 md	Any time I have seen coil bind like that , it has done some very ugly things to the bottoms of the lifters. I'd want to pull the lifters and look at them and the lobes very carefully. Pushrod measurements should be the same unless you have a lobe wiping out. Last edited by wicked; 02/10/12 11:59 AM.

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