Gas in the oil -- Initial start-up

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clifftt

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Well, finally after weeks of fussing with the ignition and pre-lubing the motor, I finally got this 273 to start up. It sounded good! A couple of days before the epic moment, I pulled the valve covers and could smell gas in the oil.

When the engine finally started, I ran it only for five seconds because I knew the oil was gas-contaminated. I've since drained it but not attempted to start it. (When I drained it, you could see a little gasoline emptying into the drain bucket.) I will later today get my priming tool and electric drill to try to totally purge the oil galleys of the bad oil. So here's my question to the forum before I break-in my new engine:

Newly machined and built 273, has a new mild Summit hydraulic cam (262/ 272, Lift .420/ .442), with stock valve train/springs/etc. Should I pop off the intake manifold and relube the cam and lifters? I was planning the break-in with Rotella 10w-40 and [FONT=&quot]"Red Line’s new Engine Oil Break-In Additive." [/FONT]
 
Question is, how did the gas get there? Was it from cranking the car for a long time trying to start it, or is there a possible carb/fuel pump problem?

Once you find out and correct the fuel problem, I would simply add new HIGH ZINC diesel oil and a new filter, and then start the cam break-in procedure as normal; 2500RPM for 20 minutes.
Good Luck!

George
 
George R: You're one of my FABO heros! I studied your long 340 Problem thread from Sept and it really helped my sort out my ignition problems. How's the car running these days? Did you ever upgrade the ignition??

Back to my problem: There were no fuel leaks, just the constant cranking of the engine, gas-down-the-carburetor.
 
Is the fuel pump new? Sounds like the diaphram in the fuel pump could be cracked,broke, split..whatever and letting fuel into the oil through the timing chain cover. I wouldn't think that much got in the oil by leaking past the rings while you were trying to start it.
 
It is a new fuel pump, Mr. Bill. And I've been trying to start this car for weeks, not every day, but some evenings and on weekends. I've pulled the plugs many times in that period, they were almost always gas-fouled.
 
Hi Cliff.
Hero, huh? LOL I don't think so!
Yes, I got the car running perfectly (with help from FABO) just in time to put it away! LOL Turned out to be a bad rebuilt points style distributor. I swapped in a MP electronic conversion kit that Bill with the 67 Cuda sold me, and it runs like a champ now.

Anyway, I too ruined the oil in my engine by cranking it for about a month (along with the starter!), so you are probably correct in saying that is what caused it. Like I said, I would just change it and go. Thats what I did anyway. Been fine ever since.
Good Luck dude!

George
 
ok, I see your dilemma. We have to then assume (uh oh) that the fuel did flood the cylinders enough to build up in the fuel...Your concerned the oil has been washed off the cam and lifters due to the length of time for the No Start fuel issue. I don't think that 5 seconds of running would have had any effect on this area inside the engine.
I think I would do what George said....and change the oil after break in time
checking for any more fuel contamination.
 
i'm with mrbill,and george r. you can smell a small amount of gasoline even in a large amount of oil. i'd just let it drain for a little longer, then fire it up on fresh oil. you are probably going to change it again real soon anyway.right?as long as you are sure that the carb and pump are not leaking, let er eat(so to speak).
 
Gentlemen, thanks for your replies. Yes, a68, I plan to replace the oil and filter (again!) after break-in.
 
Agreed with MrBill,

yet, if the fuel isn't leaking through the fuel pump which seemed to be a fairly good assumption that thats what was going on, could your carb be bad? or maybe the ignition isnt igniting the fuel in the cylinders at all.

I always run SAE-30 to break in my cams along with lubing all the parts with either lucas assembly lube or STP oil treatment durring engine assembly. After I break in the cam I then change it out with a fresh filter and fresh 30 for the next 500 miles then step to castrol 10W-30.

I have always broke in my cams at 2000 RPM for 20 minutes should I have done different on my 318??

Shawn.
 
Check the floats in the carb before doing anything more. If the floats are perforated they will sink and cause flooding to happen and will leak gas into the motor, either that or the float levels are set too high - readjust and try it. Quick way to check brass floats is to remove them and shake them next to your ear, if you hear sloshing then the float(s) are bad.
 
i heard that the new rotella has a lower zinc content than the older stuff, i used brad penn break in oil
 
66darttgt and Dart Shawn, you two were the closest figuring it out. In the past year and a half the carb has been sitting in a box, getting moved around, right side up, then upside down, then moved around,.... Pulled the top off off the carb (two barrel Carter) last Thursday night, found one of the two needles which drop thru the main jets had dislocated, so a full flow of fuel must have been coming thru that one jet while I was trying to start it. I reset the needle into the jet, verified the floats were correctly set (they were, 1/4" from the top), buttoned it up, threw it on the car, and the 273 ran beautifully for five minutes, the first time since the rebuild ........ until the oil filter adapter gasket blew! So, I'm starting a new thread. But I'm encouraged. This Barracuda has been a cold fish up to this point, and I'm glad she finally ran today.
 
good job!!! think of this in 20 years...and the fun you had....
 
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