The Stovebolt Site Forums The Shop Area Engine Shop won't start

Well the Christmas day plans to start my newly rebuilt 235 went bust. Got real close to having it catch at first but now the more I crank the worse it seems to get, just a lot of popping back thru the carbs. Thought I was 180o out of time but that wasn't it.I'm getting fuel,compression, and spark,although I don't know if the spark I'm getting is sufficient. New coil with Pertronix modified dizzy. Any suggestions guys on where to start looking?

Hy neswes, Merry Christmas, Could it be flooded? You said carbs, so you have more than one? Is fuel dripping from the carb nozzles while you are trying to start it? Double check your timing, and if that's okay, try starting it as though it's flooded, [throttle wide open to give it as much air as possible], good luck

I would double check the fuel issue that 3B mentioned as well as verify the timing.

I'm noticing that one of the carbs does not seem to be sucking vacuum now. They both were when I first tried starting it. Maybe with the backfiring thru the carbs One is messed up. Both Rochesters are squirting fuel on Offy manifold. I think tomorrow I will try an old point type dizzy I can clean up. I'm suspecting something with the spark or timing because I'm getting fuel and compression and valves are all opening and closing as I crank

As long as you installed your Pertronix correctly I would say it isn't the problem. Are your plugs gaped properly? Check the timing like previously mentioned and give it a go! Good luck and Merry Christmas!

plug gap is a loose .035 as recommended by others.I didn't install the Pertronix but it was working in the motor I took it out of.I will go over the timing again, I'm not real happy where the rotor points on the cap when I'm at TDC it seems to be between two terminals on the cap when I'm on the ball of the flywheel.

Hy neswes, All the backfiring could have forced one of your throttle plates closed, make sure that both your throttle plates are easily moved before you try starting it again. The rotor should point directly at the terminal when you timing is correct, good luck.

If its popping thru the carb My quess it would be timming , Make sure the rotor is pointed at the # 1 plug also I had the same problem years ago My Brother in law and I built a SB motor for drag racing and it got real late by the time We tried to start it ,so We had the timming off enough that it popped thru the carb being that We had been up for 24 hours We keep trying to start it and it keep popping ,We finaly got some sleep and went back to the motor later in the day it turned out when it popped thru the carb it took out the intake gaskit and had a vac. leak so You might want to check that out to after We fixed that it started and ran fine .

Pete

Try swapping the Pertronix for a known good point type distributor. It's much simpler to get the timing exactly where it needs to be while watching a set of points break than it is to guess exactly where an electronic trigger is positioned. With the flywheel ball aligned with the pointer, and both #1 cylinder valves closed, turn the distributor housing clockwise until the points close, then turn it back to the left until they just barely open. The rotor should be pointed exactly to the #1 plug wire terminal at that time.
Jerry

Thanks hotrod,and others.I will try working on the timing issue and check for vacuum leaks next time I get to work on it probably sunday.I hate to do all this cranking slow stuff on a fresh motor.It needs to fire quick and get up to break in speed.Meantime I'll clean up the old spare dizzy with the points as a backup.

See what the spark is like at the plug while cranking. If it is blue then likely the timing is off. An easy way to check the rotor position for #1 is to remove the #1 spark plug, put your thumb over the hole and have some one crank over the engine. Watch the rotor and when you feel the pressure blow your thumb off the hole make note wheere the rotor is at. Should get you close enough to start and then fine tune it from there.

Double check that the firing order to the plugs is correct.

When you assembled, did you make sure the cam timing was right?

yes cam timing was correct.I had some more thoughts during the night as is often the case. I will persist and try again soon.Got called in to work today.

SUCCESS !!! re-did the timing and it fired right up after considerable choking. Sounds really good and stong.Unforunately I've got a bad oil leak that appears to be coming from the left front oil galley plug. I can't get a good look at it right now with the radiator being in the way. Odd though, It appears to be staked in place alright. Guess I'll have to pull the radiator back out and replace the plug with a new one.Got lots of oil pressure.

By the way any suggestions on how to get the galley plug out without the danger of pushing it in? Is there a lip behind it?