pushrod not moving - The 1947 - Present Chevrolet & GMC Truck Message Board Network

tk1251k · 11-01-2007, 01:33 PM

Lifter loud at start up quiets after warmup.Passenger side rear plug fouls out constantly.Removed pass. valve cover pushrod in back cylinder barely moving. My question is how to tell if I need a cam or could lifter be stuck or what. terry

70rs/ss · 11-01-2007, 02:02 PM

Back the rocker arm nu until it clatters, then run it down till quiet and the 1/2 turn further. If it is still barely moving, then the cam is probably flat. Does it backfire through the carb? The fouled plug could be rings of valve stem seals. Do a compression test as well and make sure all cylinders are very close in pumping pressure.

grayw0lf · 11-01-2007, 02:09 PM

What engine? If its a 305, enjoy picking your new cam.

If you do find it to be a cam, you should definatley replace your (non-roller) lifters too.

68gmsee · 11-01-2007, 02:36 PM

How many miles on the engine? Older engines had a lot of problems with cam wear.

Do the easiest first... As mentioned, do the lifter adjustment and check the movement. Even if the rod bottoms out on the lifter, you should still get enough lift to open the valves unless your cam is flat.

**SactoJim** · 11-01-2007, 03:23 PM

If the cam lobe is flat, this could have something to do with the lack of zinc in motor oil these days.

What oil have you been using?

tk1251k · 11-01-2007, 03:38 PM

Truck runs fine its 1972 gmc 350 engine.I had head job about 60,000 miles ago. It runs pretty good with a small miss from plug fouling out.

tk1251k · 11-01-2007, 03:50 PM

I'll pull valve cover tomorrow and check for lift last check hardly any.

**SactoJim** · 11-01-2007, 04:05 PM

Quote:

Originally Posted by tk1251k

Truck runs fine its 1972 gmc 350 engine.I had head job about 60,000 miles ago. It runs pretty good with a small miss from plug fouling out.

I HATE to wait that long for a "head job".

68gmsee · 11-01-2007, 04:16 PM

Re: head redone at 60,000. If you have that many miles on the head, you probably have at least a bunch more on the engine. In the old days you could count on some sort of engine work at 60k to 100K.

I had a friend mechanic tell me that he always counted on replacing the cams on older model engines with over 60,000 miles on them. I believe the alloys used were not as good as in today's engines.

tk1251k · 11-01-2007, 04:27 PM

I have owned truck since 1980 from original. It had 71,000 when I bought it. It now has 372,000 miles original engine. Pan never been off no oil leaks. Changed oil ever 2500 or so. Uses about a quart every oil change. I expect alot of miles from my vehicles I am very good to them.

70rs/ss · 11-01-2007, 04:38 PM

Put a cam in it, did you honestly say 300,XXX miles?! Wow, cooler yourself lucky and spend the $150 on a cam and lifters!!

tk1251k · 11-01-2007, 04:40 PM

It has 372,OOO miles driven daily. Original paint. I thought about cam and lifters do you think that would do it?

70rs/ss · 11-01-2007, 04:48 PM

Yep, I'd do a timing chain while you are there. It is bone stock, right, just call up summit for one of there stock in house grinds and the single roller timing set, You will be able to do it for about $100-125. That is all I could see being the casue of the barely moving pushrod. The fouled plug, i am sure is a valve stem seal, or a ring. Try some of the RESTORE stuff from your local auto parts place, they swear it'll do wonders? I too would switch to the high mile type oil, they have additives in there to help with leaky seals etc.

68gmsee · 11-01-2007, 05:16 PM

Quote:

Originally Posted by tk1251k

I have owned truck since 1980 from original. It had 71,000 when I bought it. It now has 372,000 miles original engine. Pan never been off no oil leaks. Changed oil ever 2500 or so. Uses about a quart every oil change. I expect alot of miles from my vehicles I am very good to them.

Yeeeoooow! Unblievable! Must be mostly highway. But even so, you definitely take good care of the engine. I'd also do a compression check to make sure that it's still holding up there... Good luck..

cdowns · 11-01-2007, 05:50 PM

first thing i'd check before buying anyparts is to see if the rod is actually seated in the lifter

PanelDeland · 11-01-2007, 06:15 PM

And start saving your pennies.If you have 300,000 miles you will need one soon.I knew a guy who had 300,000 on a 305 and he kept everything done,oil,tune-ups and regular service.I doubt you will get more than another 50,000-100,000 miles from it.
Just an opinion but that's a lot of miles for a smallblock.

tk1251k · 11-01-2007, 07:32 PM

I think I'll go for 500,000. This has been a remarkable truck. I have driven in my business around town since I bought it. It has original a/c and nothing changed and a/c works great. Transmission automatic oaverhauled about 275,000.

Scott68-93-97 · 11-01-2007, 08:03 PM

My buddy just turned the clock on his 82 chevy with a tick over 400 a month or so ago, his grandpa owned the truck and took good care of it, and I was talking crap saying he'd never touch 400 after he got a truck that already had 320 something when he got it, I'll say go for a cam lifters and timing set and see what happens you really have nothing to loose after getting that many miles out of it to began with

tk1251k · 11-01-2007, 08:23 PM

I still remember rolling over 100 thou 200 thou never expected 300thou now looking at 400 thou.Truck goes on and on and on. Keep that oil changed. The 350 four bolt main has to be best ever made. Hate to tear into it now but I guess may have to It might not want to be disturbed.

11-01-2007, 01:33 PM	#1
tk1251k Registered User Join Date: Nov 2005 Location: Newton Posts: 174	pushrod not moving Lifter loud at start up quiets after warmup.Passenger side rear plug fouls out constantly.Removed pass. valve cover pushrod in back cylinder barely moving. My question is how to tell if I need a cam or could lifter be stuck or what. terry

11-01-2007, 02:02 PM	#2
70rs/ss Registered User Join Date: Dec 2004 Location: Northern AZ Posts: 7,271	Re: pushrod not moving Back the rocker arm nu until it clatters, then run it down till quiet and the 1/2 turn further. If it is still barely moving, then the cam is probably flat. Does it backfire through the carb? The fouled plug could be rings of valve stem seals. Do a compression test as well and make sure all cylinders are very close in pumping pressure.

11-01-2007, 02:09 PM	#3
grayw0lf Registered User Join Date: Apr 2004 Location: Clanton, AL Posts: 1,253	Re: pushrod not moving What engine? If its a 305, enjoy picking your new cam. If you do find it to be a cam, you should definatley replace your (non-roller) lifters too. __________________ 85' CUCV M1009!!! The newest addition! 6.2diesel, Th400, NP208, & only 36k miles! 70' C-10 LWB Fleetside - Looking good these days! 05' Dodge Neon 88' Winner Escape Sport 1750 - 4.3v6 94' Seadoo SP 84' Honda TRX200, bare nekkid. Just a frame & tires. Always looking for another project or any good deal!

11-01-2007, 02:36 PM	#4
68gmsee Active Member Join Date: Jul 2007 Location: Centrally located between Houston, Austin and Waco. BCS area. Posts: 7,947	Re: pushrod not moving How many miles on the engine? Older engines had a lot of problems with cam wear. Do the easiest first... As mentioned, do the lifter adjustment and check the movement. Even if the rod bottoms out on the lifter, you should still get enough lift to open the valves unless your cam is flat.

11-01-2007, 03:23 PM	#5
SactoJim Registered User Join Date: Oct 2005 Location: Sacramento, CA Posts: 1,970	Re: pushrod not moving If the cam lobe is flat, this could have something to do with the lack of zinc in motor oil these days. What oil have you been using? __________________ 72 Cheyenne SWB Fleet Nut & bolt frame off in progress...99.9999% - supercharged 383 - 4 wheel discs - relocated fuel tank - My Build Thread

11-01-2007, 03:38 PM	#6
tk1251k Registered User Join Date: Nov 2005 Location: Newton Posts: 174	Re: pushrod not moving Truck runs fine its 1972 gmc 350 engine.I had head job about 60,000 miles ago. It runs pretty good with a small miss from plug fouling out.

11-01-2007, 03:50 PM	#7
tk1251k Registered User Join Date: Nov 2005 Location: Newton Posts: 174	Re: pushrod not moving I'll pull valve cover tomorrow and check for lift last check hardly any.

11-01-2007, 04:16 PM	#9
68gmsee Active Member Join Date: Jul 2007 Location: Centrally located between Houston, Austin and Waco. BCS area. Posts: 7,947	Re: pushrod not moving Re: head redone at 60,000. If you have that many miles on the head, you probably have at least a bunch more on the engine. In the old days you could count on some sort of engine work at 60k to 100K. I had a friend mechanic tell me that he always counted on replacing the cams on older model engines with over 60,000 miles on them. I believe the alloys used were not as good as in today's engines.

11-01-2007, 04:27 PM	#10
tk1251k Registered User Join Date: Nov 2005 Location: Newton Posts: 174	Re: pushrod not moving I have owned truck since 1980 from original. It had 71,000 when I bought it. It now has 372,000 miles original engine. Pan never been off no oil leaks. Changed oil ever 2500 or so. Uses about a quart every oil change. I expect alot of miles from my vehicles I am very good to them.

11-01-2007, 04:38 PM	#11
70rs/ss Registered User Join Date: Dec 2004 Location: Northern AZ Posts: 7,271	Re: pushrod not moving Put a cam in it, did you honestly say 300,XXX miles?! Wow, cooler yourself lucky and spend the $150 on a cam and lifters!!

11-01-2007, 04:40 PM	#12
tk1251k Registered User Join Date: Nov 2005 Location: Newton Posts: 174	Re: pushrod not moving It has 372,OOO miles driven daily. Original paint. I thought about cam and lifters do you think that would do it? Last edited by tk1251k; 11-01-2007 at 04:43 PM. Reason: spelling

11-01-2007, 04:48 PM	#13
70rs/ss Registered User Join Date: Dec 2004 Location: Northern AZ Posts: 7,271	Re: pushrod not moving Yep, I'd do a timing chain while you are there. It is bone stock, right, just call up summit for one of there stock in house grinds and the single roller timing set, You will be able to do it for about $100-125. That is all I could see being the casue of the barely moving pushrod. The fouled plug, i am sure is a valve stem seal, or a ring. Try some of the RESTORE stuff from your local auto parts place, they swear it'll do wonders? I too would switch to the high mile type oil, they have additives in there to help with leaky seals etc. Last edited by 70rs/ss; 11-01-2007 at 04:49 PM.

11-01-2007, 05:50 PM	#15
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	Re: pushrod not moving first thing i'd check before buying anyparts is to see if the rod is actually seated in the lifter __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

11-01-2007, 06:15 PM	#16
PanelDeland I am a Referee of life. Join Date: Jun 2000 Location: Greensboro N.C. Posts: 13,993	Re: pushrod not moving And start saving your pennies.If you have 300,000 miles you will need one soon.I knew a guy who had 300,000 on a 305 and he kept everything done,oil,tune-ups and regular service.I doubt you will get more than another 50,000-100,000 miles from it. Just an opinion but that's a lot of miles for a smallblock. __________________ The 47-present Chevrolet and GMC Truck Message Board Network,it's owners,moderators,members,and associates of any type should not be held responsible for my opinion. You can't fix stupid,not even with duct tape. "My appearance is due to the fact that "GOD" does punish you for having too much fun!" Barrett-Jackson has perfected alchemy,they make rust into gold! "You can lead a horse to water but you can't saddle a duck" "Cleverly disguised as a 'Responsible Adult' "Sometimes your Knight in shining armor is just a retard in tinfoil"

11-01-2007, 07:32 PM	#17
tk1251k Registered User Join Date: Nov 2005 Location: Newton Posts: 174	Re: pushrod not moving I think I'll go for 500,000. This has been a remarkable truck. I have driven in my business around town since I bought it. It has original a/c and nothing changed and a/c works great. Transmission automatic oaverhauled about 275,000.



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11-01-2007, 08:03 PM	#18
Scott68-93-97 Registered User Join Date: Jul 2006 Location: Fair Oaks, CA Posts: 475	Re: pushrod not moving My buddy just turned the clock on his 82 chevy with a tick over 400 a month or so ago, his grandpa owned the truck and took good care of it, and I was talking crap saying he'd never touch 400 after he got a truck that already had 320 something when he got it, I'll say go for a cam lifters and timing set and see what happens you really have nothing to loose after getting that many miles out of it to began with __________________ 1968 Short Fleet 350/700r4 http://67-72chevytrucks.com/vboard/s...d.php?t=249435 1997 Bagged XtdCab Vortec350/4L60e http://67-72chevytrucks.com/vboard/s...44#post2286144 1993 XtdCab Longbed 4x4 6.5Turbo/NV4500 "Daily Driver" 1985 Toyota XtdCab 4x4 22re/W-56/Dual T-cases, Doug Thorley Header, Homebrew front and rear spring packs, Tons of Mods to suspension and drivetrain, 35" boggers, coming soon ARB's and 5.29's, Possible 4.3/700r4 swap

11-01-2007, 08:23 PM	#19
tk1251k Registered User Join Date: Nov 2005 Location: Newton Posts: 174	Re: pushrod not moving I still remember rolling over 100 thou 200 thou never expected 300thou now looking at 400 thou.Truck goes on and on and on. Keep that oil changed. The 350 four bolt main has to be best ever made. Hate to tear into it now but I guess may have to It might not want to be disturbed.

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