Warm start problem.

[pauldyworth]

I dont know whether anyone out there has had similar experiences but here goes with my tale of wow.

My spider has never been a great starter, normally taking several goes before I can get it going. Anyway, due to bad weather, it wasnt used over the winter period and when I came to get it started for the 1st time this year it would turn over but not catch. Beforehand, I'd made sure the battery was fully charged and the HT leads and distributer cap/rotor arm were nice and dry. Anyway I eventually checked to see whether fuel was getting to the carbs, and alas it wasn't. I narrowed it down to the fuel pump so I got a new one to replace it.

Anyway new pump fitted and hey presto started well. So off I went on a nice long run, parked up and when I came to restart it having stopped about 5 minutes earlier, it would turn over, but wouldn't catch. It was from this point I had to get a tow. Once back home, I removed the hose that feeds the carbs with fuel and turned the engine over - no fuel came out. This was beginning to annoy me. I decided to leave things and went off and did something completely different. Several hours later I returned and the bloody thing started first time.

Just to put things into prespective, the warm start issue has been a problem in the past, so anyone any ideas please help as I'm struggling to justify to the wife why the spider should remain in the family!

[Roadtrip]

Did you check to see if your fuel tank is being vented and not building up a vacumn inside? Can we assume that the fuel filter is not clogged?

[pauldyworth]

Roadtrip.

Checking to see if there's venting in the fuel tank, how do I go about checking that?

Re the fuel filter, that was recently replaced, but were that so, would a warm engine cause the problem that a cold one wouldn't?

Thanks though for your reply

Rgds
Andy

[Roadtrip]

If you take the filler cap off the fuel tank and you hear a hiss, that's a good indication that there's vacumn in there. If the tank isn't vented, as the fuel level goes down, it creates the vacumn which the fuel pump may not be able to overcome.

If you're not getting fuel to the carbs, then past this advice, you'll just have to chase it back through the lines to the tank to see why.

[John M]

Hey Andy:

What year is your car? Just a thought, but I had a similar situation when an intank fuel pump went bad. I assume you replaced the one under the car near the passenger side rear frame rail. Like around 77 it became standard to have an intank pump as well. Some even retrofit this pump. When she dies, it stops the gas flow.

Another thought...make sure that you hear the pump running that you replaced. There is a inertia switch on some of these Spiders that is located on the firewall near the windshield washer reservoir. After pulling out and pushing in the plunger several times to clean the internal connections, be sure to leave it pushed down.

Best Regards,
John M

[pauldyworth]

Hi John,

Mines a 72. I dont have particularly good mechanical knowledge, instead I'm relying on my neighbour who has. I'm not aware of the car having an intank pump.( how does that work)

The sender unit in the fuel tank feeds a rubber hose which I think runs all the way to the fuel pump which is mounted on the off side of the engine bay under the fuel filter.

Rgds
Andy

[John M]

Hey Andy:

I will leave this to RT as I have never popped the hood on a 72. I would assume that the main fuel pump is located beneath the passenger side of the car along the frame between the b pillar of the door and the fender well opening. I would be surprised if a 72 had the intank pump. There is probably a filter between the main pump and the tank as well. And possibly a screen on the pickup in the tank.

Best Regards,
John M

[Roadtrip]

Andy - Are we talking about a Euro of U.S. specification car? 72 U.S. spec cars had fuel injection, not carbs. I'm guessing that you're in the UK and that it's a Euro spec car? If it is, I'm out of my knowledge area. Is your fuel pump mechanical or electrically driven? Obviously you've got something stopping the fuel. Check the line all the way back to the fuel tank and see if there is more than one filter in-line. Things I would check:

1. Fuel tank vent
2. Change all fuel filters
3. Check that you're not getting vapor lock, although I would think that very unlikely, especially in the winter.
4. Check to be sure that the new fuel pump (if it's mechanical) isn't venting fuel into the crankcase via a bad diaphram.

[pauldyworth]

Roadtrip,

Yes you're correct in your assumption, I am from the UK and yes, the car is a UK spec one.

Thanks very much for all the pointers, I'll let you know how I get one.

Cheers
Andy