Oil pressure
Posted: Sun May 07, 2000 1:07 am
Twas about two weeks ago that I had the misfortune of having one of the
external oil lines break create a loss of oil pressure resulting in a
knock on my TC. My rescuer as able to bring my TC back to me on Thursday
and I proceded to determine what kind of damage I had. Taking a
compression test resulted showed 140/135/140/140 which looked good and
then tore down the bottom half of the engine to inspect. The number 4 rod
journal showed some scoring but all the other journals were quite fine.
Mains indicated .001 under standard (right where it was 15 years ago) and
three of the rod journals measured out at .011 under (again right where it
was 15 years ago). Took the crank in to have it manufluxed and if OK,
build up the #4 journal so as to have the rod journals ground to .020
under. Am having the Chevy rear seal conversion done also. Rest of the
engine looks fine visually.
Over the last 10 years I have been running about 40 pounds of oil pressure
when cruising and about 15 pounds at idle. Running at these pressures
resulted in no wear on the journals over the years. My theory is that
this seeming low pressure (everyone else I talk to reports 60 or more
pounds at cruising) was either acceptable or is a result of an
inaccurate gauge. I have been told that the insides of the guage can
become clogged and cause the gauge to read low and I should take a known
accurate gauge to test the working system. This is kind of hard to do
with the engine appart now.
My questions to everyone are:
How can I check the oil pump to see if it is pumping properly now?
What should I look for to determine if my pump is worn?
Should I just put the engine back together and then test and if necessary
then pull the pump off and repair?
What kind of oil pressure is adequate vs desirable?
Dave Edgar, TC 5108
external oil lines break create a loss of oil pressure resulting in a
knock on my TC. My rescuer as able to bring my TC back to me on Thursday
and I proceded to determine what kind of damage I had. Taking a
compression test resulted showed 140/135/140/140 which looked good and
then tore down the bottom half of the engine to inspect. The number 4 rod
journal showed some scoring but all the other journals were quite fine.
Mains indicated .001 under standard (right where it was 15 years ago) and
three of the rod journals measured out at .011 under (again right where it
was 15 years ago). Took the crank in to have it manufluxed and if OK,
build up the #4 journal so as to have the rod journals ground to .020
under. Am having the Chevy rear seal conversion done also. Rest of the
engine looks fine visually.
Over the last 10 years I have been running about 40 pounds of oil pressure
when cruising and about 15 pounds at idle. Running at these pressures
resulted in no wear on the journals over the years. My theory is that
this seeming low pressure (everyone else I talk to reports 60 or more
pounds at cruising) was either acceptable or is a result of an
inaccurate gauge. I have been told that the insides of the guage can
become clogged and cause the gauge to read low and I should take a known
accurate gauge to test the working system. This is kind of hard to do
with the engine appart now.
My questions to everyone are:
How can I check the oil pump to see if it is pumping properly now?
What should I look for to determine if my pump is worn?
Should I just put the engine back together and then test and if necessary
then pull the pump off and repair?
What kind of oil pressure is adequate vs desirable?
Dave Edgar, TC 5108