Bent PUSHRODS!! NEED HELP ASAP!!!! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

69GMC910 · 07-01-2002, 01:03 PM

I am adjusting the valves right at the moment, and to my suprise, I have two noticeably bent pushrods, being that it is a holiday in Canada I cannot get new pushrods today. I also have to drive 250 miles today in the old truck. Do I dare put the bent pushrods back in the truck!!!!!

Thanks!!

*Randy70C-10* · 07-01-2002, 01:07 PM

I wouldn't run them for too long. Do you have any junk ones laying around? I keep a box full of them just in case.

69GMC910 · 07-01-2002, 01:12 PM

What can happen if I run them, will i destroy the rockers or the lifters??

I unfortunatly do not have any pushrods handy.

Thanks for the tips

*Randy70C-10* · 07-01-2002, 01:14 PM

If it gets wedged in the guide, it can take a lobe off the cam.

69GMC910 · 07-01-2002, 01:18 PM

That's exactly where it is bent is in the guide. Are you allowed to flip a pushrod over?

This way the bend would not be in the guide.

Just a desperate thought!

Thanks

ebfabman · 07-01-2002, 01:19 PM

If you loose a push rod, the cam will kick the lifter out of its bore and there goes your oil pressure.

Don't use the motor if you have a bent push rod.......just MO

69GMC910 · 07-01-2002, 01:22 PM

Even if it is not bent really bad???????

69GMC910 · 07-01-2002, 01:24 PM

oh yeah, my highway RPM is 3200. This probably isn't a bonus either.

This really sucks, I gotta get home.

ebfabman · 07-01-2002, 01:25 PM

ask your self this, what made it bend in the first place?

No matter which way you install it, it won't get any straighter, only benter and probably breaker.

69GMC910 · 07-01-2002, 02:16 PM

So what you're saying is I better buy a greyhound ticket pronto?!?

This sucks.

mikep · 07-01-2002, 02:23 PM

Is NOTHING open? Even on major holidays in the US theres usually a parts store or two open that has a few pushrods laying around.

Check the slot where the pushrod comes through the head carefully. I had a head that bent pushrods on a regular basis because the hole the pushrod comes through was elongated and the pushrod was always slopping around too much causing it to bent at inopportune moments. I ended up stuck in the middle of New Mexico once for a day until I robbed one off a junk car. Its the reason I always use guideplates now that I am older and richer.

69GMC910 · 07-01-2002, 02:40 PM

ABSOLUTELY NOTHING IS OPEN!!!!!!!!!!

I didn't check the guides on the heads, I was swapping the 305 heads out for rebuilt 350 heads and just in the process of putting it all together when I realized these pushrods had turned the rocker on the valve spring so it wasn't sitting square. Thats when I came on here!

Two questions: How do pushrods bend? Why do hydraulic lifters tick?

Thanks guy's

P.S. I called greyhound and my ticket hopes aren't looking to good either

THIS IS ALREADY SUCKING ENOUGH!!

mikep · 07-01-2002, 04:20 PM

I read the other post where you asked about torqueing the rocker nuts down and it occured to me that you probably dont have a real clear grasp of how to adjust rocker arms. Thats why you have some bent ones and some ticking "lifters". Some of the rockers are too loose and some are too tight. Don't worry . Everyone has to learn to do this their own way. Some are shown how, others figure it out through books, some figure it out on their own. Some get stuck in Canada and figure it out with help on the net. Why dont you tell us the procedure you went through to adjust the rocker arms.

matt67350 · 07-01-2002, 05:03 PM

Just a thought?,but will the 350 heads fit the 305?
I thought the combustion chamber is bigger on the 350 heads?
Matthew

bigvinnie · 07-01-2002, 05:30 PM

I hope you're looking at the link I gave on your other post for adjusting the rockers.....

http://67-72chevytrucks.com/vboard/s...threadid=17082

but in the mean time I would not drive with bent rods.... your'e asking for more trouble and you'll be miles ahead (literally) by doing it right the first time...reasons for bending are a thrown/broken timing chain or having the rockers adjusted too tight...

You should really step back, read the instructions on the link I sent, get some new rods and adjust the rockers correctly. Rush jobs produce bad results.... ask more questions if you need to, but be sure of what you're doing before you do it... good luck.

dwaite72lnghrn · 07-01-2002, 07:48 PM

I am with Matt are you sure the valves clear the pistons and bore. Did you adjust them before you started the engine or were they bent from the old engine. If they took a hard jam most likely the ends of the push rods are shot and I would not drive with them. Slight bend no damage to the ends I would try to get to home. Ticking is no oil or adjusted to far and you now have solid lifters.

highwaydevil · 07-01-2002, 08:33 PM

I know this is wrong, but would it work to straigten the bent ones in a vice, and limp it home? Call before you leave and tell wheover that if you're not there but xx time, that they need to come with a tow strap... I also wouldn't drive it at 3200 rpm's. I'd go much slower, is a rental car a possibility, or are they closed too?

mikep · 07-01-2002, 08:43 PM

I'm going more with the ticking being extremely loose rockers. I'd bet that 1/2 of them are too tight and the other half are too loose. The tight ones are smacking the piston and the loose ones are having WAY too much clearance so they are ticking like all hell. My guess is that the valves were static adjusted with the cam in the wrong position ie 180 degrees out and possibly even the act of turning over the engine by hand bent the pushrods. My first guess was that you actually had a 305 and you were putting the wrong heads on it and had some interference problems but in reading your last post I see you are using 345NP pistons which are sealed power 350 units.

69GMC910 · 07-06-2002, 02:38 AM

Back for another weekend of adjusting the valves. There have been several posts on here that seem to sugest I am a complete IDIOT!

Well sorry I'm not!

Everybody knows 350 heads aren't gonna work on a 305 worth a sh!t. Vica Versa as well. This is why I am changing the heads. The pistons in the 73 350 Z-28 block bored .030 are a 10:1 piston, or so I've been told by the guy who rebuilt the thing, and everything else he has told me so far seems to check out so I believe him.

The 305 heads were excellent for compression with the 58cc chambers, unfortunately detonation is a problem as is getting high rpms with 1.74 (i am pretty sure about that) and 1.5 valves.

The 350 heads were freshly rebuilt with 1.94 and 1.5 valves and the 76 cc chamber. BIG compression drop but I am hoping for a smoother cheaper and more powerful ride. I am sick of buying octane boost and premium gasoline.

By the way, bigvinnie I did print out the information you hyperlinked in your message and it will be really helpful tommorow as I begin adjusting valves.

Thank you all for your help and I will get back to you all tomorrow if I should run into any trouble!

I gotta get to bed now, I just drove 800 kilometers today and I'm kinda tired! Oh, for all you guy's who are still stuck with that old Imperial system, thats 480 miles! I think theres only a couple countries out of like 240 or something that are not on the metric system. Wonder why.............

:

Longhorn Man · 07-06-2002, 07:23 AM

If god intended for a metric system...there woulda only been 10 apostles.

mikep · 07-06-2002, 10:55 AM

The big problem with the metric system ( besides being designed by the FRENCH and we all know what engineering geniuses they are ) is that major errors can be made in calculations simply by having a decimal point in the wrong spot at any point in the calculation. It doesnt really offer any advantage over the English Standard measurement system other than perhaps its easier to learn . We learned in the United States a long time ago that the rest of the world can go and do whatever it wants and then we'll go bail it out when it does something stupid. The English standard system works just fine for us thank you.

Longhorn Man · 07-06-2002, 06:23 PM

Even the bean counters at Dorf...oops, i ment Ford...made a mistake and looked like idiots.
When the 4.6 was installed in the Rustang..'96 or '97, they advertised it as being a 289 in there brouchers, and in adds. When in fact it is more like a 286-ish if memory serves.
I will go on record as to saying that it does make more sence...and we are just stubborn. I already hace standars tools, and I don't feel I should have to buy more. But oh well.
I just wish they would make up there minds on which will be used.
My old '81 Citation (stop giggiling you A holes!!) it was standard on the outside of the engine, yet had metric inside of it. I figured it was a chaingeover period...however, just today, i was under a newer ford at work, and I found the same frikken thing. Had to get up, and walk to my box, get my standard tools.

**68 Stepside** · 07-06-2002, 08:19 PM

281 Andy...and it's a POS, just like all f*rd products are expected to be. I own one.

TJ

Longhorn Man · 07-06-2002, 08:27 PM

How is the mangled thnunder chicken anyways?

07-01-2002, 01:03 PM	#1
69GMC910 MOTORHEAD! Join Date: May 2000 Location: Devon AB, Canada Posts: 849	Bent PUSHRODS!! NEED HELP ASAP!!!! I am adjusting the valves right at the moment, and to my suprise, I have two noticeably bent pushrods, being that it is a holiday in Canada I cannot get new pushrods today. I also have to drive 250 miles today in the old truck. Do I dare put the bent pushrods back in the truck!!!!! Thanks!! __________________ 82 GMC High Sierra VortecPro 496 12 Bolt, 3.42's AFR 265 Holley 850 Performer RPM Air Gap Hooker 2455's TCI Turbo 400 Super Street Fighter TRRC 12 Bolt Eaton Posi Mark Williams Axles Cal-Tracs Hoosier 30x10.5 Radial Slick Full weight long box pickup Current best- 11.33@117mph

07-01-2002, 01:12 PM	#3
69GMC910 MOTORHEAD! Join Date: May 2000 Location: Devon AB, Canada Posts: 849	What can happen if I run them, will i destroy the rockers or the lifters?? I unfortunatly do not have any pushrods handy. Thanks for the tips __________________ 82 GMC High Sierra VortecPro 496 12 Bolt, 3.42's AFR 265 Holley 850 Performer RPM Air Gap Hooker 2455's TCI Turbo 400 Super Street Fighter TRRC 12 Bolt Eaton Posi Mark Williams Axles Cal-Tracs Hoosier 30x10.5 Radial Slick Full weight long box pickup Current best- 11.33@117mph

07-01-2002, 01:18 PM	#5
69GMC910 MOTORHEAD! Join Date: May 2000 Location: Devon AB, Canada Posts: 849	That's exactly where it is bent is in the guide. Are you allowed to flip a pushrod over? This way the bend would not be in the guide. Just a desperate thought! Thanks __________________ 82 GMC High Sierra VortecPro 496 12 Bolt, 3.42's AFR 265 Holley 850 Performer RPM Air Gap Hooker 2455's TCI Turbo 400 Super Street Fighter TRRC 12 Bolt Eaton Posi Mark Williams Axles Cal-Tracs Hoosier 30x10.5 Radial Slick Full weight long box pickup Current best- 11.33@117mph

07-01-2002, 01:22 PM	#7
69GMC910 MOTORHEAD! Join Date: May 2000 Location: Devon AB, Canada Posts: 849	Even if it is not bent really bad??????? __________________ 82 GMC High Sierra VortecPro 496 12 Bolt, 3.42's AFR 265 Holley 850 Performer RPM Air Gap Hooker 2455's TCI Turbo 400 Super Street Fighter TRRC 12 Bolt Eaton Posi Mark Williams Axles Cal-Tracs Hoosier 30x10.5 Radial Slick Full weight long box pickup Current best- 11.33@117mph

07-01-2002, 01:24 PM	#8
69GMC910 MOTORHEAD! Join Date: May 2000 Location: Devon AB, Canada Posts: 849	oh yeah, my highway RPM is 3200. This probably isn't a bonus either. This really sucks, I gotta get home. __________________ 82 GMC High Sierra VortecPro 496 12 Bolt, 3.42's AFR 265 Holley 850 Performer RPM Air Gap Hooker 2455's TCI Turbo 400 Super Street Fighter TRRC 12 Bolt Eaton Posi Mark Williams Axles Cal-Tracs Hoosier 30x10.5 Radial Slick Full weight long box pickup Current best- 11.33@117mph

07-01-2002, 01:07 PM	#2
Randy70C-10 Account Suspended Join Date: Mar 2001 Location: Virginia Beach, Va. U.S.A. Posts: 15,320	I wouldn't run them for too long. Do you have any junk ones laying around? I keep a box full of them just in case.

07-01-2002, 01:14 PM	#4
Randy70C-10 Account Suspended Join Date: Mar 2001 Location: Virginia Beach, Va. U.S.A. Posts: 15,320	If it gets wedged in the guide, it can take a lobe off the cam.

07-01-2002, 01:19 PM	#6
ebfabman Registered User Join Date: Nov 2001 Location: Concord, NC Posts: 2,488	If you loose a push rod, the cam will kick the lifter out of its bore and there goes your oil pressure. Don't use the motor if you have a bent push rod.......just MO

07-01-2002, 01:25 PM	#9
ebfabman Registered User Join Date: Nov 2001 Location: Concord, NC Posts: 2,488	ask your self this, what made it bend in the first place? No matter which way you install it, it won't get any straighter, only benter and probably breaker.

07-01-2002, 02:16 PM	#10
69GMC910 MOTORHEAD! Join Date: May 2000 Location: Devon AB, Canada Posts: 849	So what you're saying is I better buy a greyhound ticket pronto?!? This sucks. __________________ 82 GMC High Sierra VortecPro 496 12 Bolt, 3.42's AFR 265 Holley 850 Performer RPM Air Gap Hooker 2455's TCI Turbo 400 Super Street Fighter TRRC 12 Bolt Eaton Posi Mark Williams Axles Cal-Tracs Hoosier 30x10.5 Radial Slick Full weight long box pickup Current best- 11.33@117mph

07-01-2002, 02:23 PM	#11
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	Is NOTHING open? Even on major holidays in the US theres usually a parts store or two open that has a few pushrods laying around. Check the slot where the pushrod comes through the head carefully. I had a head that bent pushrods on a regular basis because the hole the pushrod comes through was elongated and the pushrod was always slopping around too much causing it to bent at inopportune moments. I ended up stuck in the middle of New Mexico once for a day until I robbed one off a junk car. Its the reason I always use guideplates now that I am older and richer. __________________ No truck :-(

07-01-2002, 02:40 PM	#12
69GMC910 MOTORHEAD! Join Date: May 2000 Location: Devon AB, Canada Posts: 849	ABSOLUTELY NOTHING IS OPEN!!!!!!!!!! I didn't check the guides on the heads, I was swapping the 305 heads out for rebuilt 350 heads and just in the process of putting it all together when I realized these pushrods had turned the rocker on the valve spring so it wasn't sitting square. Thats when I came on here! Two questions: How do pushrods bend? Why do hydraulic lifters tick? Thanks guy's P.S. I called greyhound and my ticket hopes aren't looking to good either THIS IS ALREADY SUCKING ENOUGH!! __________________ 82 GMC High Sierra VortecPro 496 12 Bolt, 3.42's AFR 265 Holley 850 Performer RPM Air Gap Hooker 2455's TCI Turbo 400 Super Street Fighter TRRC 12 Bolt Eaton Posi Mark Williams Axles Cal-Tracs Hoosier 30x10.5 Radial Slick Full weight long box pickup Current best- 11.33@117mph

07-01-2002, 04:20 PM	#13
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	I read the other post where you asked about torqueing the rocker nuts down and it occured to me that you probably dont have a real clear grasp of how to adjust rocker arms. Thats why you have some bent ones and some ticking "lifters". Some of the rockers are too loose and some are too tight. Don't worry . Everyone has to learn to do this their own way. Some are shown how, others figure it out through books, some figure it out on their own. Some get stuck in Canada and figure it out with help on the net. Why dont you tell us the procedure you went through to adjust the rocker arms. __________________ No truck :-(

07-01-2002, 05:03 PM	#14
matt67350 Registered User Join Date: May 2001 Location: Benbrook, TX Posts: 1,060	305\350 heads Just a thought?,but will the 350 heads fit the 305? I thought the combustion chamber is bigger on the 350 heads? Matthew __________________ 69 swb stepside, rebuild and upgrade in progress

07-01-2002, 05:30 PM	#15
bigvinnie Registered User Join Date: Aug 2001 Location: escondido, ca 92026 Posts: 1,222	I hope you're looking at the link I gave on your other post for adjusting the rockers..... http://67-72chevytrucks.com/vboard/s...threadid=17082 but in the mean time I would not drive with bent rods.... your'e asking for more trouble and you'll be miles ahead (literally) by doing it right the first time...reasons for bending are a thrown/broken timing chain or having the rockers adjusted too tight... You should really step back, read the instructions on the link I sent, get some new rods and adjust the rockers correctly. Rush jobs produce bad results.... ask more questions if you need to, but be sure of what you're doing before you do it... good luck. __________________ '72 short step, 350, 700R4, tilt, ps, pdb, a/c, lowered coils, etc., other work in progress... San Diego, CA 72 Stepside Project



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07-01-2002, 07:48 PM	#16
dwaite72lnghrn Registered User Join Date: Jun 2002 Location: central pa Posts: 1,525	I am with Matt are you sure the valves clear the pistons and bore. Did you adjust them before you started the engine or were they bent from the old engine. If they took a hard jam most likely the ends of the push rods are shot and I would not drive with them. Slight bend no damage to the ends I would try to get to home. Ticking is no oil or adjusted to far and you now have solid lifters. __________________ 72 longhorn c30 502BB/th400/fact air/4.11rear/ custom camper 72 bug(the better half's) under reconstruction 2009 HHR aqua blue 71 GMC k20 350/sm465 2009 Chevy hd3500 6.6 Victory Red crew cab dually Dave & Jeanne

07-01-2002, 08:33 PM	#17
highwaydevil Registered User Join Date: Feb 2000 Location: Platteville, Colorado Posts: 1,067	I know this is wrong, but would it work to straigten the bent ones in a vice, and limp it home? Call before you leave and tell wheover that if you're not there but xx time, that they need to come with a tow strap... I also wouldn't drive it at 3200 rpm's. I'd go much slower, is a rental car a possibility, or are they closed too?

07-01-2002, 08:43 PM	#18
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	I'm going more with the ticking being extremely loose rockers. I'd bet that 1/2 of them are too tight and the other half are too loose. The tight ones are smacking the piston and the loose ones are having WAY too much clearance so they are ticking like all hell. My guess is that the valves were static adjusted with the cam in the wrong position ie 180 degrees out and possibly even the act of turning over the engine by hand bent the pushrods. My first guess was that you actually had a 305 and you were putting the wrong heads on it and had some interference problems but in reading your last post I see you are using 345NP pistons which are sealed power 350 units. __________________ No truck :-(

07-06-2002, 02:38 AM	#19
69GMC910 MOTORHEAD! Join Date: May 2000 Location: Devon AB, Canada Posts: 849	Back for another weekend of adjusting the valves. There have been several posts on here that seem to sugest I am a complete IDIOT! Well sorry I'm not! Everybody knows 350 heads aren't gonna work on a 305 worth a sh!t. Vica Versa as well. This is why I am changing the heads. The pistons in the 73 350 Z-28 block bored .030 are a 10:1 piston, or so I've been told by the guy who rebuilt the thing, and everything else he has told me so far seems to check out so I believe him. The 305 heads were excellent for compression with the 58cc chambers, unfortunately detonation is a problem as is getting high rpms with 1.74 (i am pretty sure about that) and 1.5 valves. The 350 heads were freshly rebuilt with 1.94 and 1.5 valves and the 76 cc chamber. BIG compression drop but I am hoping for a smoother cheaper and more powerful ride. I am sick of buying octane boost and premium gasoline. By the way, bigvinnie I did print out the information you hyperlinked in your message and it will be really helpful tommorow as I begin adjusting valves. Thank you all for your help and I will get back to you all tomorrow if I should run into any trouble! I gotta get to bed now, I just drove 800 kilometers today and I'm kinda tired! Oh, for all you guy's who are still stuck with that old Imperial system, thats 480 miles! I think theres only a couple countries out of like 240 or something that are not on the metric system. Wonder why............. : : __________________ 82 GMC High Sierra VortecPro 496 12 Bolt, 3.42's AFR 265 Holley 850 Performer RPM Air Gap Hooker 2455's TCI Turbo 400 Super Street Fighter TRRC 12 Bolt Eaton Posi Mark Williams Axles Cal-Tracs Hoosier 30x10.5 Radial Slick Full weight long box pickup Current best- 11.33@117mph

07-06-2002, 07:23 AM	#20
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	If god intended for a metric system...there woulda only been 10 apostles.

07-06-2002, 10:55 AM	#21
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	The big problem with the metric system ( besides being designed by the FRENCH and we all know what engineering geniuses they are ) is that major errors can be made in calculations simply by having a decimal point in the wrong spot at any point in the calculation. It doesnt really offer any advantage over the English Standard measurement system other than perhaps its easier to learn . We learned in the United States a long time ago that the rest of the world can go and do whatever it wants and then we'll go bail it out when it does something stupid. The English standard system works just fine for us thank you. __________________ No truck :-(

07-06-2002, 06:23 PM	#22
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	Even the bean counters at Dorf...oops, i ment Ford...made a mistake and looked like idiots. When the 4.6 was installed in the Rustang..'96 or '97, they advertised it as being a 289 in there brouchers, and in adds. When in fact it is more like a 286-ish if memory serves. I will go on record as to saying that it does make more sence...and we are just stubborn. I already hace standars tools, and I don't feel I should have to buy more. But oh well. I just wish they would make up there minds on which will be used. My old '81 Citation (stop giggiling you A holes!!) it was standard on the outside of the engine, yet had metric inside of it. I figured it was a chaingeover period...however, just today, i was under a newer ford at work, and I found the same frikken thing. Had to get up, and walk to my box, get my standard tools.

07-06-2002, 08:19 PM	#23
68 Stepside huh? Join Date: May 2000 Location: Washington, Illinois Posts: 5,690	281 Andy...and it's a POS, just like all frd products are expected to be. I own one. TJ __________________ Someday when I'm lonely, Wishing you weren't so far away, Then I will remember Things we said today. RIP El Jay*

07-06-2002, 08:27 PM	#24
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	How is the mangled thnunder chicken anyways?

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