piston cylinder wall scuff wear pattern
#1
Thread Starter
Supreme Member
Joined: Mar 2002
Posts: 4,812
Likes: 0
From: 62656
Car: 1991 S10 pickup 2700lbs
Engine: 4.3L Z TBI
Transmission: 700R4
Axle/Gears: 3.08 7.625"
piston cylinder wall scuff wear pattern
disassembled the 85 LG4 engine today down to a bare block, it has 196k miles on it
some of the cylinders have a pretty wide piston scuff wear pattern across the inside and outside of the bores(across-ways)
some of the piston pins are tight and some are not
worn pins would cause accelerated wall wear like this correct ?
just wondering
this engine is funny cuz damn it still has the factory steel shim head gaskets although pretty rotted,
and it has the original GM nylon teeth cam timing gear
and GM oil pump
and all the bearings are still silver but are GM stamped and some are really badly scratched/gouged)
surprised the hell out of me
i call that pretty damn good for an old tired LG4
it still ran but smoked a good amount of blue smoke
its all going to the machine shop tomorrow probably
one hell of a dirty tired carboned up engine
ive seen worse(mostly due to bearings still being silver) but not alot worse lol
thanks
some of the cylinders have a pretty wide piston scuff wear pattern across the inside and outside of the bores(across-ways)
some of the piston pins are tight and some are not
worn pins would cause accelerated wall wear like this correct ?
just wondering
this engine is funny cuz damn it still has the factory steel shim head gaskets although pretty rotted,
and it has the original GM nylon teeth cam timing gear
and GM oil pump
and all the bearings are still silver but are GM stamped and some are really badly scratched/gouged)
surprised the hell out of me
i call that pretty damn good for an old tired LG4
it still ran but smoked a good amount of blue smoke
its all going to the machine shop tomorrow probably
one hell of a dirty tired carboned up engine
ive seen worse(mostly due to bearings still being silver) but not alot worse lol
thanks
#2
Supreme Member
iTrader: (1)
Joined: Jul 2004
Posts: 10,763
Likes: 4
From: Calgary, AB, Canada
Car: 1982 Trans-Am
Engine: 355 w/ ported 416s
Transmission: T10, hurst shifter
Axle/Gears: 10 bolt, true-trac, 3.73
Re: piston cylinder wall scuff wear pattern
I imagine the loose pins are somewhat related to the bore pattern, i'm having a tough time visualizing how, but if they match up in your engine (ie bore with most wear has loosest pin) then...
Doesn't really matter now though eh?
I can't pass shame onto you about rebuilding a 305 (haha ) at least tell me you're not going to rebuild it with all stock type parts right?
Doesn't really matter now though eh?
I can't pass shame onto you about rebuilding a 305 (haha ) at least tell me you're not going to rebuild it with all stock type parts right?
#3
Joined: Sep 2005
Posts: 26,602
Likes: 1,904
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: piston cylinder wall scuff wear pattern
I wouldn't worry about it... it's all going in the trash anyway. Pistons & block especially. Since no one in his right mind would spend $2000 rebuilding a 305 when $50 more would get a 350, and NO DOUBT you're in you're right mind, none of the parts in question will ever see the light of day again; and so that 305's death mode at 200k miles hardly matters any more.
Thread
Thread Starter
Forum
Replies
Last Post
dimented24x7
Transmissions and Drivetrain
7
09-17-2015 07:58 AM