Today's Posts Mark Forums Read Calendar
Go Back   NJFBOA - Home of New Jersey's Camaros and Firebirds > Tech Forums > Engine / Power / Tuning

Notices


Reply
 
Thread Tools
Old 03-24-2008, 11:51 AM   #1
Untamed
 
Untamed's Avatar
 
Join Date: Aug 2004
Location: Hillsborough, NJ
Posts: 3,200
iTrader: (1)
Piston Slap?

I've got an '88 Trans Am, 305 TBI. The heads belong to the engine and there have been no mods to the block, cam, crank, or heads.

At idle my car has a fast, rythmic clicking sound on the passenger side head. The click continues, though faster, as the engine revs. Could this be valve / piston slap? It only happens on the passenger side head, and it is NOT an exhaust leak (as I checked for this as the car ran). I'm going to get video / audio tomorrow after work.

If it is piston slap, how do you fix it? What causes it? It's definately a clicking sound, which made me think of the valve train instead of the pistons themselves.

Thanks!
__________________
I USED TO HAVE an 85 Camaro 305 4bbl, 90 Firebird V6, 97 Firebird V6 (10 speakers!). Despite the two family vehicles, 3 kids, wife and mortgage, I can finally realize the dream - 88 TA almost all stock... for now.

http://www.cardomain.com/id/untameddave

Wanted this - , but ended up with this - for free. Can't argue with free.
Untamed is offline   Reply With Quote
Old 03-24-2008, 12:55 PM   #2
WildBillyT
Ayatollah of Rock N Rolla / Admin
 
WildBillyT's Avatar
 
Join Date: Mar 2006
Location: Parts Unknown
Posts: 12,573
iTrader: (10)
I have never heard piston slap sound like a "tick", only like a diesel "chug". It sounds like you may have a bad lifter or something like that.
WildBillyT is offline   Reply With Quote
Old 03-24-2008, 05:39 PM   #3
GP99GT
Mr Fantastic
 
GP99GT's Avatar
 
Join Date: Aug 2004
Location: West Milford NJ
Posts: 7,917
iTrader: (2)
could be a bad lifter, worn rocker, bent pushrod, or light piston slap...ive heard LS1 piston slap sound slightly like a click, though usually it doesnt sound that way

edit: pull off the valve cover on that side and start wiggling things, turn it over by hand as you do so....see if anything is loose
__________________
Matt

B18B1 FTW

Last edited by GP99GT; 03-24-2008 at 05:39 PM.
GP99GT is offline   Reply With Quote
Old 03-24-2008, 07:40 PM   #4
Tru2Chevy
Co-Founder / Site Admin
 
Tru2Chevy's Avatar
 
Join Date: Jul 2004
Location: Ewing, NJ
Posts: 22,476
iTrader: (8)
Social Networks:

Yea, could be a loose rocker as well. My guess would definitely be something in the valvetrain before piston slap though.

- Justin
__________________
1999 Camry - Beigemobile DD
2002 Suburban - Wife's DD
2004 Grand Cherokee - Not running / Project / Selling?

Tru2Chevy is offline   Reply With Quote
Old 03-24-2008, 07:51 PM   #5
JL8Jeff
Hippy Mod, Bergermeister Meisterberger, Moderator
 
JL8Jeff's Avatar
 
Join Date: Aug 2004
Location: Ewing
Posts: 6,216
iTrader: (3)
Piston slap will go away as it warms up. My 93 LT1 had a little bit and my 00 SS has it when first started up in the cold. It's annoying, but goes away within a minute or 2. If you still hear that ticking noise, it could be ignition(spark jumping) or valvetrain related. Hopefully it's not a bearing.
__________________
69 Z28 JL8 4 wheel disc brakes - being restored
09 Silverado Z71
JL8Jeff is offline   Reply With Quote
Old 03-24-2008, 10:06 PM   #6
Untamed
 
Untamed's Avatar
 
Join Date: Aug 2004
Location: Hillsborough, NJ
Posts: 3,200
iTrader: (1)
After doing some reading online it sounds more like a lifter problem. What would visually indicate that? A loose rocker? This is a flat tappet, not a roller. I also read up on "lashing" but haven't a clue how to set it. Would this cause something to be loose enough that it would cause a continuous clicking sound?

After re-reading this, it may be time to call someone in to look at it. Starting to get in over my head here. :P
__________________
I USED TO HAVE an 85 Camaro 305 4bbl, 90 Firebird V6, 97 Firebird V6 (10 speakers!). Despite the two family vehicles, 3 kids, wife and mortgage, I can finally realize the dream - 88 TA almost all stock... for now.

http://www.cardomain.com/id/untameddave

Wanted this - , but ended up with this - for free. Can't argue with free.
Untamed is offline   Reply With Quote
Old 03-25-2008, 08:04 AM   #7
WildBillyT
Ayatollah of Rock N Rolla / Admin
 
WildBillyT's Avatar
 
Join Date: Mar 2006
Location: Parts Unknown
Posts: 12,573
iTrader: (10)
Quote:
Originally Posted by Untamed View Post
After doing some reading online it sounds more like a lifter problem. What would visually indicate that? A loose rocker? This is a flat tappet, not a roller. I also read up on "lashing" but haven't a clue how to set it. Would this cause something to be loose enough that it would cause a continuous clicking sound?

After re-reading this, it may be time to call someone in to look at it. Starting to get in over my head here. :P
Dave:

Have a look.

http://www.cranecams.com/?show=techarticle&id=2
WildBillyT is offline   Reply With Quote
Old 03-25-2008, 08:43 PM   #8
Untamed
 
Untamed's Avatar
 
Join Date: Aug 2004
Location: Hillsborough, NJ
Posts: 3,200
iTrader: (1)
Thanks Bill! I think I followed most of it, however it reinforces my thoughts about getting help.
__________________
I USED TO HAVE an 85 Camaro 305 4bbl, 90 Firebird V6, 97 Firebird V6 (10 speakers!). Despite the two family vehicles, 3 kids, wife and mortgage, I can finally realize the dream - 88 TA almost all stock... for now.

http://www.cardomain.com/id/untameddave

Wanted this - , but ended up with this - for free. Can't argue with free.
Untamed is offline   Reply With Quote
Old 03-25-2008, 08:52 PM   #9
johnjzjz
.
 
johnjzjz's Avatar
 
Join Date: Feb 2006
Posts: 1,385
iTrader: (0)
Chevy cams have a rep to be on the soft side , you might have a cam lobe that has worn off and because of that will sound like a loose tappet , normally they stay quiet with out something going on , if you can take the valve cover off and run the motor the bad lobe, on its rocker arm will not move up and down as much as the others ((( caution ))) oil will spray all over doing this so be advised , you can try to adjust it but the noise wont go away --- if its just loose it will go away but thats almost never -- just what i have seen doing this -- jz
johnjzjz is offline   Reply With Quote
Reply

  NJFBOA - Home of New Jersey's Camaros and Firebirds > Tech Forums > Engine / Power / Tuning


Posting Rules
You may not post new threads
You may not 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

Forum Jump

» Sponsor List














All times are GMT -5. The time now is 05:04 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.