305 motor knocking
#1
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Car: 1988 Pontiac Firebird Formula
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 3:23
305 motor knocking
my motor is knocking and im not sure if its a spun bearing or a stuck valve. help please?
#2
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Car: 1988 Pontiac Firebird Formula
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 3:23
Re: 305 motor knocking
i also noticed that my oil pan is dented from the bottom. previous owner must have jacked the car up by it....could that cause any problems??
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Car: 1985 & 1988 trans am
Engine: 350 tpi ; 355
Transmission: 700r4 auto; converting to 6 speed
Axle/Gears: 9 bolt 3:27 posi; 2.73 open
Re: 305 motor knocking
could have cracked the crank if it hit it but it prolly is spun bearing how is the oil pressure but the po would have to be pretty dumb to jack by the oil pan
#4
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Car: 1988 Pontiac Firebird Formula
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 3:23
Re: 305 motor knocking
well it still starts up and runs just knocks, would a cracked crank still even hold up enough to run? and idk i havent checked the oil pressure yet, the cars been sittin in my garage since it started knocking. and yeah, the po wasnt too bright about cars ha
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Car: 86 IROC-Z28
Engine: LB9
Transmission: 700r4
Axle/Gears: 3.27
Re: 305 motor knocking
I have the same thing going on. My motor runs great, and starts on the first rotation and has good oil pressure. After reading a lot of boards I think I am going to check my timing chain first to see if it is hitting the cover. If that's not it then I am sure it is internal.
#7
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Car: 1988 Pontiac Firebird Formula
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 3:23
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#8
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Car: 1988 Pontiac Firebird Formula
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 3:23
Re: 305 motor knocking
I have the same thing going on. My motor runs great, and starts on the first rotation and has good oil pressure. After reading a lot of boards I think I am going to check my timing chain first to see if it is hitting the cover. If that's not it then I am sure it is internal.
you got a nice maro though
#9
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Car: 1988 Pontiac Firebird Formula
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 3:23
Re: 305 motor knocking
found out what it was. Shot wrist pin. should be fun to fix....
#10
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Re: 305 motor knocking
found out what it was. Shot wrist pin.
If it's already torn down and it REALLY has that extremely rare and unusual problem you are saying it does, throw that thing in the trash and move on.
Money spent on a 305 short block is money wasted.
Heads, cam, exhaust, tune-up, etc., sure, as long as it's not 305-specific (like heads sometimes are); routine maintenance, of course; short block, never.
Sounds like it's time to install a "bore kit".
#11
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Car: 1988 Pontiac Firebird Formula
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 3:23
Re: 305 motor knocking
And you "found this out"... how? Only way to tell something like that is to tear it down.
If it's already torn down and it REALLY has that extremely rare and unusual problem you are saying it does, throw that thing in the trash and move on.
Money spent on a 305 short block is money wasted.
Heads, cam, exhaust, tune-up, etc., sure, as long as it's not 305-specific (like heads sometimes are); routine maintenance, of course; short block, never.
Sounds like it's time to install a "bore kit".
If it's already torn down and it REALLY has that extremely rare and unusual problem you are saying it does, throw that thing in the trash and move on.
Money spent on a 305 short block is money wasted.
Heads, cam, exhaust, tune-up, etc., sure, as long as it's not 305-specific (like heads sometimes are); routine maintenance, of course; short block, never.
Sounds like it's time to install a "bore kit".
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