1999 Tahoe bending pushrods? - Great Lakes 4x4. The largest offroad forum in the Midwest

Go Back   Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech
GL4x4 Live! GL4x4 Casino

greatlakes4x4.com is the premier Great Lakes 4x4 Forum on the internet. Registered Users do not see the above ads.
Search
Reply
 
Thread Tools Search this Thread
Old September 23rd, 2009, 04:17 PM   #1
Yetti
Buy a Fiat! Save the UAW!
 
Yetti's Avatar
 
Join Date: 11-05-05
Location: 20 minutes south of Hell...
Posts: 14,384
iTrader: (10)
Mentioned: 2 Post(s)
Default 1999 Tahoe bending pushrods?

my buddy at work has an odd problem with a 5.7 vortec in a taho turd. it has 150,000 miles and is just now in the habit of bending pushrods? anyone seen this lately?
__________________
Yetti
Yetti is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old September 23rd, 2009, 05:08 PM   #2
jbsjunk
Meow
 
jbsjunk's Avatar
 
Join Date: 03-01-08
Location: Almost Allendale Mi
Posts: 14,705
iTrader: (36)
Mentioned: 15 Post(s)
Default

Same spot every time, or different locations? If it was in the same cyl, I would think something's keeping the valve from opening all the way. Does it run alright?

I've never run into this, kinda odd.
jbsjunk is offline   Reply With Quote
Old September 23rd, 2009, 06:10 PM   #3
Yetti
Buy a Fiat! Save the UAW!
 
Yetti's Avatar
 
Join Date: 11-05-05
Location: 20 minutes south of Hell...
Posts: 14,384
iTrader: (10)
Mentioned: 2 Post(s)
Default

I was thinking something along the lines of a bent valve jammed shut. it would almost have to be. nothing generates that kind of presure to bend stuff like that? it bent one pushrod while cranking??? I think the head needs to come off.
__________________
Yetti
Yetti is offline   Reply With Quote
Old September 23rd, 2009, 06:19 PM   #4
jbsjunk
Meow
 
jbsjunk's Avatar
 
Join Date: 03-01-08
Location: Almost Allendale Mi
Posts: 14,705
iTrader: (36)
Mentioned: 15 Post(s)
Default

I was thinking the same thing. Only one pushrod is bending? Would kind of rule out something in the cyl. Unless for some reason one of the keepers came out and jammed between the head and the retainer. Long shot for sure.
jbsjunk is offline   Reply With Quote
Old September 24th, 2009, 07:45 AM   #5
95geo
newbie
 
95geo's Avatar
 
Join Date: 11-05-05
Location: dryden
Posts: 5,775
iTrader: (6)
Mentioned: 0 Post(s)
Default

carbon buildup on the stem causing it to hang up? if it did it at idle speeds then that kind of rules out the weak valve spring idea and tagging a piston at WOT and causing the stem to bend... it could already be bent... who knows... at 150k it could be anything.

Time for a rebuild!
95geo is offline   Reply With Quote
Old September 24th, 2009, 08:17 AM   #6
spr_chicken
Senior Member
 
spr_chicken's Avatar
 
Join Date: 05-12-08
Location: Grand Haven / Michigan
Posts: 1,114
iTrader: (9)
Mentioned: 0 Post(s)
Send a message via MSN to spr_chicken Send a message via Yahoo to spr_chicken
Thumbs down

if its bending the push rod its going to take out the cam also
spr_chicken is offline   Reply With Quote
Old September 24th, 2009, 08:39 AM   #7
litfoot
Member
 
litfoot's Avatar
 
Join Date: 04-20-09
Location: hubbard lake, MI
Posts: 51
iTrader: (1)
Mentioned: 0 Post(s)
Default

timming chain shot and vavles hitting piston!!
litfoot is offline   Reply With Quote
Old September 28th, 2009, 07:54 PM   #8
mseguin1984
member
 
mseguin1984's Avatar
 
Join Date: 04-20-09
Location: rapid city, MI
Posts: 93
iTrader: (0)
Mentioned: 0 Post(s)
Default

over revving ? does he know the procedure for properly adjusting valves? you adjust the intake when the exhaust closes and exhaust when the intake opens. take to zero lash and go another half turn. Hope i helped
mseguin1984 is offline   Reply With Quote
Old October 17th, 2009, 05:43 AM   #9
Yetti
Buy a Fiat! Save the UAW!
 
Yetti's Avatar
 
Join Date: 11-05-05
Location: 20 minutes south of Hell...
Posts: 14,384
iTrader: (10)
Mentioned: 2 Post(s)
Default

I forgot to update this thread. it was a bent valve jammed shut! it has a bur built up on the stem and apparently slowed it down enough on the return to let the piston catch it once or twice.
__________________
Yetti
Yetti is offline   Reply With Quote
Reply
Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 11:29 PM.


Powered by: vBulletin, Copyright 2000 - 2012, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
Page generated in 0.13830 seconds with 47 queries