305 knockin

Feb 17, 2004 52 Replies

I have a 82 Chev Scottsdale with a mid to late 80's 305 in it and a



4speed top loader tranny, after it gets up to running temp it starts knockin, sounds like a bearing thats gone, and then goes away after another
15 -20 minutes of running. Any suggestion?

Confused


is the oil pressure holding good? if so it probably ain't a bearing. my guess is either an exhaust gasket leak (they sound like a rod until the engine warms up and the manifolds swell from the heat) or probably a bad trowout bearing. (after their worn they rattle alot until they heat up a little). some sound just like a rod. try holding he clutch in a little and listen closely. does the knock go away? if so i wouldn't worry to much about it until it gets to where it annoys you.... ee-ee

"Trowout bearing"? At least he didn't call it the "Throwup bearing!"

Doc

"Eee Eee" wrote

Good advice...so far you don't annoy me, so I won't worry too much about your posting.

Ian

"Eee Eee" wrote in

Who are you responding to?

Ian

. .

305 knockin Group: alt.trucks.chevy Date: Tue, Feb 17, 2004, 1:15pm (CST+1) From: snipped-for-privacy@sympatico.ca (Jamie) =A0=A0=A0=A0=A0=A0 I have a 82 Chev Scottsdale with a mid to late 80's 305 in it and a 4speed top loader tranny, after it gets up to running temp it starts knockin, sounds like a bearing thats gone, and then goes away after another 15 -20 minutes of running.

Any suggestion?

Confused =3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D

Jamie, how's that section 8 thing going?

as to yer knock'n noise.... go on outside.....carry a steak knife with you.

Now.....go over to that garden hose you've been meaning to fix the end on..........

Now .....cut about 4 feet off the bad end. (you'll never miss it....remember...you've been meaning to fix it anyway)

Now....get that motor to knocking..... shove one end of the garden hose in yer......

ear......and use the other end to probe around, and try to narrow that knock down to a specific area.

Post yer results, and you'll get some better guess's.

oh yeah.......and fix yer garden hose!

Marshall M. Onster ~wonders if yer engine has a heat riser on the exhaust~ =3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D

. . In todays episode of the hit sitcom series... alt.truck.chevy......we here snipped-for-privacy@webtv.net squeel like a pig and go..... (Eee=A0Eee), realizing he jest yanked the zipper up before he yanked his yanker in.... he hit's himself side the head and writes this.....

Duh! U dimbo

=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D

Hey, PingPOng paddle pet......... yer fly's down.

Yer momma know you play with that thing??

You gonna go blind, if'n you don't stop.

marsh ~takes a sip of the shroom juice....and waits~ =3D=3D=3D =3D=3D=3D

Hey Marsh, good to see ya back. Maybe you should splain to Eee Eee how copy/paste works so people know what he is talking about and to whom? I'm not too familiar with the web boxes. JR

If memory serves the WebTV did provide the original post when you hit "reply". It's up to you what you want to do with it after that.

William

+++++++++++++++++= *Knocking* release bearing? That's a new one to me.... Could you discribe it as a ticking sound? If so, I'll guess loose exhaust manifold bolt- Like Marsh said, use a hose to your ear and you could find an exhaust leak easily. They usually happen on the rear cylinders....

a garden hose! r u that stupid? hahahhahahahhaaaa!!! anything u hear is gona sound like its com'n from the top because the crank and bearings are always submerged in oil. sheesh, what a DUMB answer. sounds like another doc-dorkieo remedy to me. doesn't he use those listening devices alot:) u 3 should listen to each others brain if ya's have 1. probably find some loose marbles.

garden hose huh... LoL

Crankshafts are never submerged in oil. It seems the more you insult, the dumber you get. b

A hose or a broom stick will work well as a make shift stethoscope. Basic ingenuity isn't one of your strong points is it?

What an amazingly ignorant comment.

You'd be the expert.

I'm guessing that your only familiarity with a garden hose probably involved a Gerbil...

This sets up an interesting contest, whether the "u 3" find their marbles faster than you can find the shift key on your keyboard.

"LoL" would be an understatement.

A hose is THE perfect way to find an exhaust leak, if you think it isnt (for the exhaust leak) ,your the stupid one. I would agree it isnt so great for a knocking brearing or the like. A long screwdriver works alot better for that.

oil pressure is at about half on the factory gauge at start up and drops to about a quarter at running temp. the motor(used, unknown milage) was just put in at the beginning of jan. so a exhaust leak is possible too, i had someone else put it in because it too damn cold here in the winter to work in the driveway. the knockin doesn't change when the clutch is pushed in. will try the garden hose stethoscope on the weekend and see if i can narrow it down. would improper timing cause something like this? still confused

yes...improper timing could very easily cause a (ping) knock, however if you retard the timing you may very easily take the knock away. this will cause some loss of power and performance but may take the worry out of what you hear. apparently you have a worn out engine there. i would try to keep it full of oil at all times and not to exceed speeds of over 55 mph. you should get lots of use from it yet.

good luck... ee ee:

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required