prime carbs prior to starting??

[escapedan]

This is my first attempt with SU's. I've just reinstalled my twin SU's after replacing all the hoses and removing the smog equipment and now I cant seem to get the car started. Should I remove the float bowl covers and fill them with gas?? At the recommendation of a local mechanic I tried spraying starting fluid into the carbs while turning the car over, but no luck. Just lots of popping and smoke coming out of the carb!! Any suggestions?

[Victor Laury]

Something is up. The bowls fill in just a few cranks. Have a doubt? open them up and look. Timing, Points, Firing order, fuel supply is the order of my "why it don't run" investigations.

[escapedan]

Thank you very much! I will recheck all this first thing tomorrow...dont want to p.o. the neighbors tonight!

[Chino 240Z]

Hi there,

Victor is right, it should fuel up to the bowls in a few short cranks, after that, you might open the bowls and have a peek. You can verify you are pumping gas from removing a fuel line feeding the carbs and having someone crank it while you hold a glass jar, not plastics- gas may eat it up, you can see the volume of fuel in a couple of seconds, it don't take much to fill a bowl. Victor has the starting list of investigations, you'll want to check and double check things one at a time. Read up on a couple of previous threads hear in the SU carb. department and see how several of us have gone thru the same thing. We gotta kinda eliminate alot of misc. possiblities that can come up with a car if it has been sitting for a while, ya know. But give it a go, and people here will follow up on you and will have some ideas to offer.

:classic:

[Dtsnlvrs]

Take the valve cover off and phyisicaly manipulate the fuel pump arm to prime the bowls....it take quite a bit more than a few turns to fill empty bowls.

[escapedan]

Thanks for the excellent tips!! I would be totally lost without this site! I'll be heading straight to the garage when I get home and will post the results! Hopefully good news!

[Daniel]

use small funnel or tear a beer can in half and make a lip in it.Put some gas in the can and pour it into the overflows(the hoses on the carb bowls tops that go to the air cleaner)

[Chino 240Z]

Everything will be just fine cranking it over in sort 30 to 40 second intervals while the gas is working its way up from the tank. Holding the key over for long duration is only going to heat up the starter and add wear. If it isn't getting fuel to the carbs then you need to stop, back up a second and investigate from the pump back to the tank.

If you must prime the carbs, a little fuel down the vent might do the trick, but too much is the same thing as too high of fuel level in the bowl and here begins flooding the carbs (the dribble out the carb syndrome) gassing up the cylinders spark plugs, then its gotta be wide open throttle, crank, crank, crank to air it out. Maybe by then you have just drained the bowls to the right level and the gas has made it up from the tank and your back to square 1 and ready to go.

If you need to get inside the valve cover for something else besides to manually pump the gas pump, maybe check valve cleareance, timing chain wear & tension, spings, dirt, then great, you might want to have a new cover gasket to put on incase the old one sticks, splits, and desides to give you a leak, don't forget to check what the torque is on the bolts when you put the freshly cleaned cover back on. (I need to bring out the manual at this point, I don't remember certain things any more either from the gas fumes of the flooded carbs or from partying like a rock star years ago. . .)

If you are like me I just want to get the dang thing some fuel, sit in the drivers seat,crank the key get it running enough to jump out quickly grab the throttle linkage and keep her going while I make some adjustments to smooth her out. Let her warm up, idle a bit and then listen to what she is telling you she needs. I hate it when ya open a can of worms compounding one problem with another.

I have to remind myself "K.I.S.S." (Keep It Simple Stupid)

That's me! Good Luck.