View Full Version : valves rattling
lookingaround
10-04-2008, 04:15 PM
what would cause my valves to rattle? its a 406 dome motor with brodix track1's 645 solid roller cam that was degreed in. 1.5 harland sharp roller rockers msd distributor msd 6al box msd coil 750 aed double pumper. no matter where i move the distributor the valves rattle. will cheap gas cause this? i havent set the timming with a light yet just by ear to get it going. any help would be appreciated. thanks Avery
Tod74
10-04-2008, 04:25 PM
Mild DETONATION MAKES A RATTLE SOUND...spark knock whatever you want to call it.
lookingaround
10-04-2008, 04:36 PM
what causes that? how do i fix it? lol
hammertime
10-04-2008, 04:56 PM
what causes that? how do i fix it? lol
Lack of octane, I get it once in awhile with 87 octane on the primer plus :lol:
lookingaround
10-04-2008, 04:57 PM
thanks David
hammertime
10-04-2008, 04:58 PM
what fuel you running ?
lookingaround
10-04-2008, 05:07 PM
right now its just 87 octane. i just got it going and that all they had around here. everybody was running out of gas.
hammertime
10-04-2008, 06:08 PM
Id just it up next time should fix it.
zipper06
10-04-2008, 07:27 PM
right now its just 87 octane. i just got it going and that all they had around here. everybody was running out of gas.
Add a couple bottles of Heet it will raise the octane by 2 to 4 points since it's almost pure alcohol. That will tell you if you have an octane problem.
JMO
Zip.
lookingaround
10-04-2008, 07:59 PM
where can you get it at zipper?
zipper06
10-04-2008, 09:19 PM
Autozone on the shelf. we used it last week in the 3700 lb Biscuyne that ran 6.87, street legal.
Zip
lookingaround
10-05-2008, 02:02 PM
here it is with the exhaust on it now.
http://i83.photobucket.com/albums/j289/ProBlaze/th_exhaust.jpg (http://s83.photobucket.com/albums/j289/ProBlaze/?action=view¤t=exhaust.flv)
bjuice
10-05-2008, 02:31 PM
Autozone on the shelf. we used it last week in the 3700 lb Biscuyne that ran 6.87, street legal.
Zip
Zip i also used this stuff to rid some water out of the tank of my wifes 2005 Dodge Hemi....cleared the bad gas right up along with some injector cleaner..
Good stuff !
kbartley
10-05-2008, 06:46 PM
Be careful, a domed 400 does not like pump gas at all. I know I learned the hard way. I just love to bulid the 400 block's. About 12 yrs. ago I had one detonate sooooo bad that I could take a pencil & lay it between the bore's. Remember, the wall's are thin to start with. Especially today's pump gas, it's awful. If the picture you have w/ you're post is what you are running I would reccomend you to get a drum of 110 purple gas. It will be cheaper then replacing part's. At least try a few gallon's anyway. Kris
dparker
10-05-2008, 07:42 PM
Not that Id fully recommend it, but some of the roundy pounders in the area mix av gas(airplane) fuel 1/2 and 1/2 with unleaded and it seems to work for them. It runs about 4.50 a gallon here. That predetonation will hurt parts if not fixed though.
lookingaround
10-06-2008, 06:09 PM
well got some racing fuel in it set the timing at 36 and she is all better. thanks guys.
desoto30
10-07-2008, 12:47 PM
I don't know what the laws are where you are,or if the avgas is the same but last I checked,avgas has TEL (Tetra ethyl lead)why its safe for aircraft but too dangerous for cars who would know?I suspect that it would probably be illegal for use in cars,but just to test,well,You'd have to be really unlucky to get busted.As far as safety is concerned I wouldnt worry at all!It'd be no worse than pump gas.