knock on startup, oil pressure 0psi to 15psi
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From: jackson, new jerzy
Car: 87 iroc-z
Engine: LB9 305 tpi
Transmission: t5
Axle/Gears: 9bolt BW 3.45 (G92)
knock on startup, oil pressure 0psi to 15psi
Salute fellow 3rd gen'ers. 87 IROC-z 5speed with oil cooler, she has 160k miles has been daily driver for 6 years. The oil gauge has always been near 60lbs of oil regardless of accuracy it had oil pressure. My problem now is poor oil pressure. Im stuck at clearance problems for the oil pan removal. I hope this information is enough to get a good reply/and or help future readers. Im all ears to possible solutions for poor oil pressure.
The car is set to 1250-1500rpms on cold start and 500 idle. Now when the car does a cold start I have a slight knock; I even pre lubed the engine by bumping the starter. When its a warm start, it doesnt knock noticeably. Sometimes while taking off from a stop, if I baby it, she knocks a little not extremely loud but somewhat noticeable.
Whats weird is the oil pressure on cold start is normal, but on warm/hot start the oil pressure is the same as if Im driving. I get 15-20lbs of oil while driving, at stop lights 0lbs of oil according to the gauge, and 15lbs of oil if I slightly increase the rpms at stop lights.
I drove out of state and when I went to leave the first of 2 stores in a small mini mall, definitely on first hot startup it had a valve tap for 1-2 seconds. Havent heard it since. I believe because the engine is not sufficiently being supplied with oil, the oil pickup line/screen could be clogged? Im trying to get the pan off, the back of the oil pan just barely cleared the bell housing of transmission to pull out but is being hung on what my dad says the front main bearing cap, but I believe I seen its being held on the crank.
Im not a certified mechanic, but have always worked on my own %&^$, including my old 86 lg4 sport coupe. My father is well knowledged with cars. I have been reading many posts about removing oil the pan/knocking problems and Im currently stuck trying to get the little extra clearance to pull the oil pan. The motor is jacked little over 3 inches (eye to eye) in-between motor mount brackets
I just rebuilt the top end last winter; the intake gasket was letting anti freeze in the oil. So Im pretty dang sure the top end/valves are not the problem. Had a valve job done with new guides, new seals, and new seats. Also put new rocker arms and nuts. When the motor was apart there was glycol (mayonnaise substance) all under and in valves; which was cleaned out, except the oil pan. It never struck my mind. After the rebuild we did put 4 quarts of oil and 1 transmission fluid to ensure the system was clean. Changed oil after test drive.
I dont have an engine hoist so I compromised and made a makeshift lift. I have the chain hook on the lower front side alternator bracket and for balance also bolted on to the a/c bracket on top. Chain then lifted by a come-along attached to a long 4x4 piece of wood hung in loops of 2 straps. The other end of straps tied to a 2x4 piece of wood across 3 beams of the garage's roof (if you have use a 4x4 too, for extra beam support), which works well.
I loosened motor mounts, removed oil filter, starter, distributor cap and rotor, dust cover for flywheel, y pipe too since it was loose at cat anyway, the transmission mount nut is loose, put motor at Top Dead Center and spun the motor 1 revolution on timing putting me at 180 degrees (or 6 o'clock), and tried jacking the transmission a little, AFTER I maxed out my *** along lift AND bottle jack started raising the car. My engine has a factory oil cooler so I loosened it looking for clearance/wiggle room to of no help.
I jacked all I could its now lifting car so transmission is probably maxed not motor. Here I am for advice hoping someone can fill in the missing link I need for clearance.
Any help or shared knowledge is appreciated. Ill be checking back to keep up with replies.
p.s. worst case scenario ill loosen transmission bolts so motor can be pulled to front of car for my clearance, but Ive read you dont have to.
The car is set to 1250-1500rpms on cold start and 500 idle. Now when the car does a cold start I have a slight knock; I even pre lubed the engine by bumping the starter. When its a warm start, it doesnt knock noticeably. Sometimes while taking off from a stop, if I baby it, she knocks a little not extremely loud but somewhat noticeable.
Whats weird is the oil pressure on cold start is normal, but on warm/hot start the oil pressure is the same as if Im driving. I get 15-20lbs of oil while driving, at stop lights 0lbs of oil according to the gauge, and 15lbs of oil if I slightly increase the rpms at stop lights.
I drove out of state and when I went to leave the first of 2 stores in a small mini mall, definitely on first hot startup it had a valve tap for 1-2 seconds. Havent heard it since. I believe because the engine is not sufficiently being supplied with oil, the oil pickup line/screen could be clogged? Im trying to get the pan off, the back of the oil pan just barely cleared the bell housing of transmission to pull out but is being hung on what my dad says the front main bearing cap, but I believe I seen its being held on the crank.
Im not a certified mechanic, but have always worked on my own %&^$, including my old 86 lg4 sport coupe. My father is well knowledged with cars. I have been reading many posts about removing oil the pan/knocking problems and Im currently stuck trying to get the little extra clearance to pull the oil pan. The motor is jacked little over 3 inches (eye to eye) in-between motor mount brackets
I just rebuilt the top end last winter; the intake gasket was letting anti freeze in the oil. So Im pretty dang sure the top end/valves are not the problem. Had a valve job done with new guides, new seals, and new seats. Also put new rocker arms and nuts. When the motor was apart there was glycol (mayonnaise substance) all under and in valves; which was cleaned out, except the oil pan. It never struck my mind. After the rebuild we did put 4 quarts of oil and 1 transmission fluid to ensure the system was clean. Changed oil after test drive.
I dont have an engine hoist so I compromised and made a makeshift lift. I have the chain hook on the lower front side alternator bracket and for balance also bolted on to the a/c bracket on top. Chain then lifted by a come-along attached to a long 4x4 piece of wood hung in loops of 2 straps. The other end of straps tied to a 2x4 piece of wood across 3 beams of the garage's roof (if you have use a 4x4 too, for extra beam support), which works well.
I loosened motor mounts, removed oil filter, starter, distributor cap and rotor, dust cover for flywheel, y pipe too since it was loose at cat anyway, the transmission mount nut is loose, put motor at Top Dead Center and spun the motor 1 revolution on timing putting me at 180 degrees (or 6 o'clock), and tried jacking the transmission a little, AFTER I maxed out my *** along lift AND bottle jack started raising the car. My engine has a factory oil cooler so I loosened it looking for clearance/wiggle room to of no help.
I jacked all I could its now lifting car so transmission is probably maxed not motor. Here I am for advice hoping someone can fill in the missing link I need for clearance.
Any help or shared knowledge is appreciated. Ill be checking back to keep up with replies.
p.s. worst case scenario ill loosen transmission bolts so motor can be pulled to front of car for my clearance, but Ive read you dont have to.
Last edited by me420; Feb 25, 2012 at 06:49 PM.
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