Starting issues

NW75spider · Post by **NW75spider** » Mon May 29, 2006 6:59 pm

Ok, so this is my first fiat ('75 124 Spider), and when I purchased it, the PO started it and it ran fine. It took him some time to get it started, but I have not been able to get her to run yet! Well, I should say I had it running twice, but then she died.

The PO showed me that the fuel sending unit was bad and it would need spark plugs and wires. I purchased all of these and installed them, which was between the first time he had it running, and the second time. Well, when I went to pick it up, I could not get her running, but the PO was later able to. Unfortunately, the thermostat was stuck, and she started to overheat quickly. I had her towed (flat bed) home.

I have replaced the thermostat (uses the external unit). I can hear the fuel pump clicking away just before I engage the starter. The car has a couple of gallons in the tank. She will just crank away, but I have only had her running once, and that was for only about 30 seconds, then she died again.

I am thinking she is not getting fuel, and thought I should change the fuel filter (or atleast test to make sure fuel is moving).

So, what else should I look at? Are there any "tricks" I should know about getting her running?

So Cal Mark · Post by **So Cal Mark** » Tue May 30, 2006 1:46 am

a couple of common problems are a bad accelerator pump so there isn't a squirt of fuel into the venturi when you pump the pedal, and a choke that doesn't close. If you have both of these problems at the same time, it can be really difficult to get the engine to start. Both are easily checked with the air cleaner lid off. With the engine off (I know, it won't start) look down the primary throttle bore and work the accelerator link. You should see a stream of fuel into the venturi. And obviously, if you don't have to open the choke to see into the venturi, the choke is not closing

If neither of these are the problem, check the gap of the points

NW75spider · Post by **NW75spider** » Tue May 30, 2006 12:55 pm

Thanks for the reply Mark.

The choke seems to be working fine, so I will check the accelerator pump next.

If it is the accelerator pump, will this require a carb rebuild?

So Cal Mark · Post by **So Cal Mark** » Tue May 30, 2006 2:34 pm

you can replace the accel pump without doing any other service to the carb. So, the choke is closed with a cold engine?

NW75spider · Post by **NW75spider** » Tue May 30, 2006 2:38 pm

Yes, the choke is closed with a cold engine.

where can I pick up a replacement accel pump (I believe I have the standard/stock webber)?

NW75spider · Post by **NW75spider** » Wed May 31, 2006 12:37 am

Ok, I found the problem, but am not sure what is causing it.

When playing with the throttle, fuel does squirt into the venturi, so the accelerator pump appears to be working. The choke works fine.

So, I took the top of the carb off and discovered the fuel bowl was lower than the intake for the jets. I poured some fuel in the bowl to get the level up, and then buttoned the whole thing back up. She started right away. But, she died after idling for a minute. Fuel bowl was empty again.

Refilled the bowl, and she started right back up again. Then died after a minute of idling.

I took the hose connected to the fuel filter and tipped it to see if fuel would come out, and it does. This seems to indicate that the fuel lines are not clogged. I then removed the nut at the end of the carb where the fuel lines connect and took the filter out and cleaned it up. Filled the bowl one more time and she started again, but then died as before. The bowl is again almost dry.

So, what causes the fuel to move through the line and into the bowl? Is it just the pump in the trunk? Or is vacuum used also?

I have not checked the gap of the points, since it starts and idles fine, but dies when the fuel is emptied from the bowl.

So Cal Mark · Post by **So Cal Mark** » Wed May 31, 2006 2:35 am

the fuel pump fills the bowl until the float rises and the needle valve is closed. If the car has been sitting for awhile, the needle valve may be stuck to the seat with varnish. You'll have to remove the top again, remove the float and needle and clean it, then blow through it. Make sure the float moves freely

brad131a4 · Post by **brad131a4** » Thu Jun 01, 2006 2:02 am

I just had this problem with another spider and it turned out to be a clogged filter. The only problem was that it kept getting clogged so the car would start and run until sediment would clog it up again. Best thing to do is to get the clear filters and have one by the tank and in the engine compartment. It may sound like overkill but I found that there was gas going to the carb but not enough to keep it running and in some cases to not start at all. I found that when the car is running the filter looks like there is hardly any gas in it so I could tell when the filter by the gas tank was clogged as it would be totally filled with gas. We found out that gravity can help in this case as the exit of the filter was pointing down so we changed that and had it pointing up . So far no problems as now the sediment can't clog up the filter. You will understand what I mean when you get the filter and look at it and how the gas flows through it. I would also blow out the fuel line from the tank to the engine just to make sure.

NW75spider · Post by **NW75spider** » Thu Jun 01, 2006 12:20 pm

Thanks Brad. I checked everything at the carb, and all jets and needle valves are clear, but the bowl won't fill. I figured I was time to check the line between the tank and engine. Your hint of the see through filters at both ends is really good, and should help a lot.

Unfortunately, I can't do much testing right now since my throttle cable broke. I have two ordered (one as a spare) and hope to get them soon. In the mean time, I will get the filters and blow out the line.

So Cal Mark · Post by **So Cal Mark** » Thu Jun 01, 2006 1:19 pm

I read back thru your posts and the only mention I see about the pump is that you can hear it clicking. Are you sure the pump is actually pumping fuel?

NW75spider · Post by **NW75spider** » Thu Jun 01, 2006 1:39 pm

Actually, no. I need to also test to see if it is working. With the trunk open, the pump is VERY loud, but when closed and the engine running I did not notice it. Of course I was focused on the fact it was running since I knew it would quit again soon.

The fuel pump appears to be a NAPA auto parts unit.

I have assumed it was working since I saw the car run for several minutes when I was thinking of buying it, but it might have failed......

So Cal Mark · Post by **So Cal Mark** » Thu Jun 01, 2006 3:29 pm

electric pumps are loud without fuel in them, pretty quiet when pumping. I'd check the pickup unit and the condition of the hose between the pickup and pump. A split hose on the intake side of the pump will cause it to suck air

NW75spider · Post by **NW75spider** » Thu Jun 01, 2006 3:55 pm

Thanks for the info Mark. I will look at that before doing anything else.

Mad-Machine · Post by **Mad-Machine** » Thu Jun 01, 2006 10:22 pm

as a side note.. NEVER look down the throats of the carb when the car is running. I made that mistake once and lost some hair for my efforts when my spider decided that would be a good time to backfire through the carb.

Also... did you check the float level itself? If the arm is off, the jet may be cutting off fuel to the car too soon.

NW75spider · Post by **NW75spider** » Thu Jun 01, 2006 11:54 pm

Float level is fine and appears to be working correctly. I hope to test the fuel pump and the lines on Friday.