strange noise and setting the valves? - Team Camaro Tech
Engine General Engine Discussion.

 
LinkBack Thread Tools Display Modes
post #1 of 7 (permalink) Old Apr 15th, 04, 12:38 AM Thread Starter
Senior Tech
Marc
 
Join Date: Jul 2001
Location: Belgium
Posts: 546
Post

Hi,

I have hydraulic lifter that shoudnt need any tunes, but i never checked the valves load since i got the car 2 years ago.

Cruising around 2900 RPM without any load, the engine makes a small vibration noise, which desapear at other engine rotations and other loads. It comes clearly when decelarating slowly under light load from 3100 RPM to 2600 RPM.
I have no idea what this might be.
It doesn't seem to make any noise at still stand at the same 2900 RPM, but i will check that again to be sure, with a body's ears in the engine bay.

Now anyway i think about checking the load on the valves, i know how to do it theorically on the V8 and understood the working of it.

The thing is i did it once on a 4 cylinder 1.5 l engine, whose crankshaft could simply be rotated by hand. Now a V8 is something else and i wonder HOW damn i will rotate the crankshaft accuratly?
I don't like the idea of the starter without ignition because i feel like it won't be accurate.

Thank for your inputs.

Camaro 1968, propane 327ci, Big Brake, Hotchkis, T56
Marc is offline  
Sponsored Links
Advertisement
 
post #2 of 7 (permalink) Old Apr 15th, 04, 09:19 PM
Senior Tech
 
Join Date: Jun 2003
Location: columbus oh.
Posts: 891
Post

is this a standard or automatic transmission?could be an out of balance clutch or driveshaft,wheel bearings?
anyway the tried and true way of adjusting lifter preload on a chevy v8 here in the usa is to warm the engine to running temprature,remove a valve cover and,one at a time back the adjustingnut out until you hear the rocker arm clatter then turn it back in until the clatter just stops,then slowly add 1/4 to 1/2 turn more(make sure they are all the same)to preload the lifter.repeat for the other 15 and you're done!
a few tips if you do it this way...try to find some oil deflectors that clip on the rockers to keep oil from shooting all over your engine bay,keep idle as low as possible,have an extra quart of oil on hand.also clean the rocker cover rails and gasket surfaces of the valve covers thoroughly and apply a thin film of silicone sealer to the valve cover and cover side of the gasket only.on the head side use a thin layer of heavy(clean)grease like wheel bearing grease. this will allow you to remove the valve cover and gasket(carefully)as a unit next time and save you $ on gaskets.also the "spreaders"that fit between the valve cover hold down bolts and the covers are a good idea to help prevent leaks.
they help to evenly distribute the bolt's load.
good luck!
Eric

86 camaro,383,topline vortecs,scat crank,wiseco forged 9.5:1,6"scat rods,comp xs282s,performer rpm,750 proform vac sec,msd in cap, hooker coated 1 5/8"headers,3"flowmaster,700r4,2800 stall,3.42 10 bolt posi,hotchkiss lca's,aje tube k member & a-arms
SLEEPER 86 is offline  
post #3 of 7 (permalink) Old Apr 15th, 04, 09:24 PM
Senior Tech
 
Join Date: Jun 2003
Location: columbus oh.
Posts: 891
Post

just remembered...a worn pilot bushing can cause what you describe as well.

86 camaro,383,topline vortecs,scat crank,wiseco forged 9.5:1,6"scat rods,comp xs282s,performer rpm,750 proform vac sec,msd in cap, hooker coated 1 5/8"headers,3"flowmaster,700r4,2800 stall,3.42 10 bolt posi,hotchkiss lca's,aje tube k member & a-arms
SLEEPER 86 is offline  
 
post #4 of 7 (permalink) Old Apr 20th, 04, 01:13 AM Thread Starter
Senior Tech
Marc
 
Join Date: Jul 2001
Location: Belgium
Posts: 546
Post

hey, thank you !
This isn't the way i would have think to set valves ! I would have done it 'theorically' with searching the balance point of valves, etc ...

I'll set the valves the way you told me then. But i wonder how i will avoid to splash oil every where..

For the noise : I listened at still and it seems it doesn't come from the engine. It seems my exhaust vibrate at that RPM's . Strange hum? but i sratched the headers to exhaust attach point on a bump, maybe therefore...

Marc

Camaro 1968, propane 327ci, Big Brake, Hotchkis, T56
Marc is offline  
post #5 of 7 (permalink) Old Apr 20th, 04, 01:19 AM Thread Starter
Senior Tech
Marc
 
Join Date: Jul 2001
Location: Belgium
Posts: 546
Post

oh, i forgot to tell you about the transimssion i have a restored (by myself) muncie 21.

Camaro 1968, propane 327ci, Big Brake, Hotchkis, T56
Marc is offline  
post #6 of 7 (permalink) Old Apr 20th, 04, 04:13 PM
Senior Tech
 
Join Date: Jun 2003
Location: columbus oh.
Posts: 891
Post

yeah marc,exhaust leaks can sound a lot like lifter noise.as for the oil splash most automotive stores will sell little clips that fit over your rocker arms to deflect oil.get the all metal ones,the teflon and spring wire types don't work well.also keep the idle as low as possible.
Eric

86 camaro,383,topline vortecs,scat crank,wiseco forged 9.5:1,6"scat rods,comp xs282s,performer rpm,750 proform vac sec,msd in cap, hooker coated 1 5/8"headers,3"flowmaster,700r4,2800 stall,3.42 10 bolt posi,hotchkiss lca's,aje tube k member & a-arms
SLEEPER 86 is offline  
post #7 of 7 (permalink) Old Apr 21st, 04, 03:41 AM
Senior Tech
 
Join Date: Apr 2001
Location: Newark, Ohio
Posts: 706
Post

What about adjusting the valves with Harland Sharp roller rockers? Dont you have to use a feeler guage on these rockers? This is a stupid question but: My new car runs vacuum advance and my old car didn't when it says to set the timing, disconnect the vacuum advance and plug it. Which end are you plugging the port from the carb or vacuum canister?

Later, Erik

67 Camaro Pro Street, 540 Bill Mitchell Merlin big block, Merlin Aluminum heads, Holley 870, hydraulic camshaft, 2" Hooker Super Comp headers, Mallory and Crane ignition system, TH400, 2600 stahl, Ford 9" w/ 4:10 gears and posi.
Erik Beckett is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.



Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome