No start

[Kayser28]

I drove my new 1977 911 S Carrera to St Louis from Las Vegas last Monday with no troubles. Today it got warm enough to start it up and take it for a drive. Unfortunately when I turn the key the starter makes a thunk noise and the tach pegs but the motor does not budge. I have tried jumping the car but no change. Any ideas, please don't tell me the motor is siezed up.

Thanks

Mike

[911pcars]

Okay. The motor is probably not seized.

Check the battery connections first. Make sure they're clean and tight.

If the battery and battery connections are good (you jumped and still no go), it's either the ignition switch, starter solenoid or starter. The thunk might indicate the solenoid is working (engages the pinion gear) but the motor isn't spinning.

You can verify system voltage (12+ volts) at the battery and switch terminals (during cranking). If that's okay, remove and bench test the starter assy. with jumper cables and a battery.

Sherwood

[cstreit]

THe tach usually pegs and/or jumps when there is a grounding issue.

If a jump did not improve this, it sounds even more suspect.

First check your battery to frame ground connection remove, clean, re-install.

Second check your transmission ground strap. It connects to the chassis and then to a bolt on your transmission right over the trans mount. A 1" wide copper braided ground cable. Remove it, clean the contacts and re-install.

If this fails check your battery voltage when attempting to start. Post voltage drop here.

Lastly, try and turn the motor over by hand. Put your pulley wrench on the alternator nut. Put soem pressure on the belt and turn. See if you can get it to rotate.

Not sure if you're "badly stranded" or not. If so, let us know, there is probably someone earby who can help, or, I'll give you my number and we can walk through some options.

Chris

[Kayser28]

Thanks for the help. My fan belt was too loose to turn the motor. But I put it in gear and pushed it forward in my garage (or at least I rocked it back and forth a bit). And this seemed to fix it. The starter worked fine.

Now I think I have a bad fuel pump though. When I turn the key to the accessory position it gets loud up front (fan or pump noise, I assume it is the fuel pump). When I turn the key the starter cranks and cranks. After a good long time it starts. It runs at fast idle for about 2 minutes and then settles down and sounds smooth. When I drive it though it will stall. I can get it to drive and accelerate but if I put in the clutch the idle drops and then the engine stalls. When I restart it , it starts and then immmediately dies unless I intervene and catch it with the gas pedal.

While I was out driving around it back fired and then died. It turned over but showed no signs of starting for about 5 minutes. I added a bit of gas and finally it turned over and ran great until I got home.

In the garage just now it was very hard to start, but then fired off and did the fast idle for a minute and then settled to normal idle speed. I revved the engine to 3000 rpm then 3500 rpm a few times and then it died. At this point when I turn the key it starts right up then immediately dies.

I think the combination of cold starting difficulty, erratid idle when warm, starting and immediately dying and backfiring underload is a fuel pump.

Any other ideas?

Thanks,
Mike

[cstreit]

Mike,

Sounds possible. A failing fuel pump would cause those symptoms. Did you possibly overheat the starter trying to get it going and cause it to seize temporarily?

Unless the starter jammed in a forward position (unlikely) the rocking wouldn't have helped unless you cleared a hydrolock in the motor from too MUCH fuel... doesn't sound like it though.

It's easy enough to check. Pull an injector and place it in a glass jar. Turn the car to run and depress the air plate... Does fuel spray?

The fuel pump should sound almost like a buzz. There is an auxilliary fan up front near the jack that can make noise. The fuel pump is near the crossmember underneath.