Need an opinion a good one on Bent valves
02-28-2009, 03:15 PM
#1
On The Tree
Thread Starter
iTrader: (2)
Join Date: Sep 2008
Location: deptford /new jersey
Posts: 100
Likes: 0
Received 0 Likes
on
0 Posts
Need an opinion a good one on Bent valves I have 100psi on num 2 4 an 6 clyinder could i ever possibly bend that many valves at once or is that a sign of a blown head gasket i have a **** load of misfires
02-28-2009, 04:39 PM
#3
FormerVendor
iTrader: (2)
Join Date: Dec 2001
Location: Baton Rouge, LA, USA
Posts: 1,954
Likes: 0
Received 3 Likes
on
3 Posts
Easy problem to diagnose if you have access to compressed air. You can remove the schrader valve from your compression tester and connect it to the cylinder(s) in question.
If you have air leaking into the intake, its a bent intake valve.
Exhaust header, its exhaust.
Excessive air into the crankcase, most likely a piston or ring issue, possibly head gasket.
If you pressurize the cooling system, cracked head or blown head gasket.
Shane
If you have air leaking into the intake, its a bent intake valve.
Exhaust header, its exhaust.
Excessive air into the crankcase, most likely a piston or ring issue, possibly head gasket.
If you pressurize the cooling system, cracked head or blown head gasket.
Shane
02-28-2009, 09:42 PM
#5
TECH Fanatic
iTrader: (9)
Join Date: Feb 2002
Location: Morton IL
Posts: 1,126
Likes: 0
Received 0 Likes
on
0 Posts
Easy problem to diagnose if you have access to compressed air. You can remove the schrader valve from your compression tester and connect it to the cylinder(s) in question.
If you have air leaking into the intake, its a bent intake valve.
Exhaust header, its exhaust.
Excessive air into the crankcase, most likely a piston or ring issue, possibly head gasket.
If you pressurize the cooling system, cracked head or blown head gasket.
Shane
If you have air leaking into the intake, its a bent intake valve.
Exhaust header, its exhaust.
Excessive air into the crankcase, most likely a piston or ring issue, possibly head gasket.
If you pressurize the cooling system, cracked head or blown head gasket.
Shane
03-01-2009, 09:22 AM
#6
12 Second Club
Join Date: Jul 2008
Location: amarillo, tx
Posts: 106
Likes: 0
Received 0 Likes
on
0 Posts
Yes, you can bend that many valves at once...or more. Especially if the valves floated at high rpm. But if you have 100psi with your compression checker I doubt you would have that much with bent valves, usually it won't hardly hold any pressure.
Do what Shane's telling you, that's a 'poor mans' [no offense Shane] leak down tester. You won't get a leak down percent to know how bad they are but you will hear where it's coming from.
Are you 100% sure the piston is at TDC and doesn't move when you hit it with the air? Sometimes the motor can roll over a bit when you hit it with air and open a valve just enough to cause a 'leak'.
Do what Shane's telling you, that's a 'poor mans' [no offense Shane] leak down tester. You won't get a leak down percent to know how bad they are but you will hear where it's coming from.
Are you 100% sure the piston is at TDC and doesn't move when you hit it with the air? Sometimes the motor can roll over a bit when you hit it with air and open a valve just enough to cause a 'leak'.
Trending Topics
03-01-2009, 10:52 AM
#8
FormerVendor
iTrader: (2)
Join Date: Dec 2001
Location: Baton Rouge, LA, USA
Posts: 1,954
Likes: 0
Received 3 Likes
on
3 Posts
Remove the rockers from the cylinder you are testing to prevent the cam from opening the valves during the test...
Shane
