|
04-02-2003, 01:15 PM | #1 |
Spank 'em if you got 'em!
Join Date: Nov 2002
Location: Kansas City
Posts: 628
|
Help: Clatter box
Need some advice.
Whenever I get on the gas I hear this persistant clatter. I checked the exhaust and everything is tight. I had my valve covers off a few days ago and checked the rods. They were good except for one thing, they had some play from side to side. Is that normal? I started the engine and the valve clatter didn't seem bad at all. But, I get the covers back on and head out the following morning and there it is again. I have good oil pressure. Adjusted the timing couple days ago. Any ideas or suggestions? Thanks everyone! Ro
__________________
Long Knight '71 C-20, 350ci, TH350, Edl. 1406 Carb w/elec.choke, Ignitor ignition, Viper Tires, Orange Dipstick |
04-02-2003, 01:20 PM | #2 |
Senior Member
Join Date: Nov 2001
Location: Pasadena, Texas, USA
Posts: 1,005
|
Is it the valve train clattering or is it detonation from the pistons?
Sam
__________________
72 LWB chevy truck. Pasadena, Texas |
04-02-2003, 01:31 PM | #3 |
Spank 'em if you got 'em!
Join Date: Nov 2002
Location: Kansas City
Posts: 628
|
That's what I can't narrow down. I just put headers on not too long ago and maybe they just give off a hollow clatter vibration. Mostly what I need to figure out is if it is something bad that I need to fix or if it is something that doesn't really matter, because my truck is a daily driver that goes over 50 mile/day.
It only does it when I really get on it.
__________________
Long Knight '71 C-20, 350ci, TH350, Edl. 1406 Carb w/elec.choke, Ignitor ignition, Viper Tires, Orange Dipstick |
04-02-2003, 01:31 PM | #4 |
Registered User
Join Date: Oct 2002
Location: Parksville, B.C. Canada
Posts: 637
|
If your timing is not too far advanced it shouldn't be detonating, I was thinking maybe you had a lifter not pumping up; but if it's only clattering when you get on the gas, that probably would not be a lifter. I think you need to give us more details about this particular sound you're hearing. Also, does it idle well? And do you have a vacum gauge to check the engine with?. They will tell you a lot about whats going on inside the engine.
__________________
1969 G.M.C 3/4 Ton 920 (Canadian Version) 307 3 speed, currently apart 1998 Chevy 1/2 ton ex cab V-6 5 speed 1967 Chevy SWB - project truck; not started just yet |
04-02-2003, 01:35 PM | #5 |
Spank 'em if you got 'em!
Join Date: Nov 2002
Location: Kansas City
Posts: 628
|
No vac guage, engine runs slightly rough at idle. Can't seem to even out the idle. Could a bad vac. advance cause the clatter?
__________________
Long Knight '71 C-20, 350ci, TH350, Edl. 1406 Carb w/elec.choke, Ignitor ignition, Viper Tires, Orange Dipstick |
04-02-2003, 01:41 PM | #6 |
Senior Member
Join Date: Nov 2001
Location: Pasadena, Texas, USA
Posts: 1,005
|
I would take it easy till you get the problem pinned down. What octane gas are you useing in it and tell me about your engine, ( size, high performance, stock etc)
Sam
__________________
72 LWB chevy truck. Pasadena, Texas |
04-02-2003, 02:14 PM | #7 | |
CCRider
Join Date: Feb 2000
Location: Olive Branch,MS,USA
Posts: 2,232
|
Quote:
__________________
72 GMC Sierra SWB almost finished---- 84 Softail Olive Branch MS |
|
04-02-2003, 04:21 PM | #8 |
Spank 'em if you got 'em!
Join Date: Nov 2002
Location: Kansas City
Posts: 628
|
Engine was rebuilt 7k miles ago. Only upgrade was an RV cam and a Edl 1406. All new pumps. Heads were re-built along w/ engine. Put headers on recently, can't find any leaks.
What would happen if you plugged the end of the tail pipe and shot compressed air up the pipe from an air compressor? That wouldn't mess anything up would it? I figure that would be a sure way to check for leaks, right?
__________________
Long Knight '71 C-20, 350ci, TH350, Edl. 1406 Carb w/elec.choke, Ignitor ignition, Viper Tires, Orange Dipstick |
04-02-2003, 04:32 PM | #9 |
Senior Member
Join Date: Nov 2001
Location: Pasadena, Texas, USA
Posts: 1,005
|
No that would not work like that, when the engine is sitting there off, some of your intake and axhaust valves are open, and you would just blow air out the carb. If it is detonation, try going with a higher octane of gas, or back your timeing down a little. If it is in the valve train, go back and readjust the valve, see if that helps. When you rebuilt the engine, how was the clearence in the bore/ piston? The pistons could have too much clearance and cause the rattleing, but go after the easy things first. It could just be you need to go with a higher octane. That would be a quick fix, I have a completly stock 305 in my truck ( 86' ) and it does not like any thing but 92 93 octane, if I try to go with 89, it clatters bad, if I back my timeing down any at all, I loose a lot of power and the truck is hard to get rolling. LOL! So I keep my timing a little on the advanced side. It is hard for us to say what it is with out hearing this.
Sam
__________________
72 LWB chevy truck. Pasadena, Texas |
04-03-2003, 12:47 AM | #10 |
its all about the +6 inches
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
|
Quick way to see if it is detonation, fill up with 92/93 octain, or what ever is high test at your fillin station. If it stops doing it, you found the problem.
and at 50 miles a day, you should be able to fill up in a couple days. |
04-03-2003, 12:57 AM | #11 |
Registered User
Join Date: Sep 2001
Location: Hacienda Heights, California USA
Posts: 474
|
When you mentioned clatter and that it gets louder when you get on it, I thought for a minute that you ended up with my ex-girlfriend, but then she clattered before she even got in the truck.
On your problem, check the timing, but it may be too much piston clearance. Sounds like my tired Z28. Damn thing almost sounds like a diesel when the timing is too advanced.
__________________
'72 GMC custom camper 350/350 |
04-03-2003, 01:58 AM | #12 |
Recovering Truck Driver
Join Date: Mar 2002
Location: Orleans, NE USA
Posts: 1,883
|
Check your torque converter bolts, if they work loose, it will give a good clatter......sounds about like a rod bearing spun.
__________________
67 K-20 350, SM465, Eaton rear, 4.56 no spin option 00 Dodge 2500 4x4, 24V cummins, 5 speed Chad South Central Nebraska |
04-03-2003, 09:58 AM | #13 |
Spank 'em if you got 'em!
Join Date: Nov 2002
Location: Kansas City
Posts: 628
|
I'll check this stuff out this weekend. Thanks for the input everyone! It's always good to have an idea of what to look for instead of going in blind. This is such a great site for information! Thanks again.
__________________
Long Knight '71 C-20, 350ci, TH350, Edl. 1406 Carb w/elec.choke, Ignitor ignition, Viper Tires, Orange Dipstick |
Bookmarks |
|
|