PDA

View Full Version : twin 302s fuel smell



nova1
04-26-2008, 03:41 AM
anyone have an idea. I have twin 302's 30 over 30hrs on each motor or so
put new edl alum heads with roller rockers on last year, hyd lifters cam is about 500 lift if you factor the ratio of the rockers. Performer alu. intake and speed demon 650's, MSD dist. and Msd ign boxes.
when I run the motors. My hose coming from the valve cover to the breather, when I'm adjusting my carbs I noticed a strong fuel smell vapor coming from this hose. Both motors do this.
Is this ok, am I running to rich or or are my rings not seating yet,,?

RICHARD TILL
04-27-2008, 03:47 PM
could it just be blowby or does it have a raw fuel smell.

nova1
04-27-2008, 04:11 PM
Smells a little rich of fuel with a litle postive preasure coming out.. However I checked the dip stick and oil looks good.
I guess it could be some blow by and the rings never seated but both motors are doing it and both have very low hours and are about 6 moths apart on the rebuilds.. When I really starting noticing it was when I changed the cams and put a new set of timing gears and double roller chain on. Old gears were set to retartd a couple of degrees. I set these straight up.
With the new cam the firing order is now different used to be the 351 timing order, now 302. I run about 16 deg. initial (per speed demon carb spec.), with a max of 36-38 deg. The motor run very, very strong. This shit just drives me nuts. Hence posting at 3:30am...

RICHARD TILL
04-28-2008, 08:45 PM
have you looked at the spark plugs? reading them will answer lots of questions. thats how you tell if its running rich or lean and the right heat range.

nova1
04-29-2008, 04:04 PM
I'll pull one. I think they should be light tan. How or who would know what is the correct heat range?

centerhill condor
04-29-2008, 06:17 PM
run it...and gun it!
CC

Oldmop
05-05-2008, 11:07 AM
Not sure where to tell you to start but high fuel smell in the oil is not good, one motor you may have an idea of where to look but both it has to be something common to both. If it were just one I would be looking at a fuel pump issue if stock block mounted, a weeping diaphragm can do what you are speaking of.
Phil

Oldmop
05-05-2008, 11:08 AM
I'll pull one. I think they should be light tan. How or who would know what is the correct heat range?
Look for a darker color but not black, tan is fine in a car but lean in a boat.
Phil

nova1
05-10-2008, 03:03 AM
never thought about the fuel pumps. Both are at least 12 years old. Good possibility. Was thinking of changing someday anyhow and adding a fuel preassure gage so I know whats going to the Demon carbs.
I pulled a plug on both motors and they look good, light black not wet, I see no hot marks or oil build up either.