Help with starting!!

eubanksae · 12-24-2003, 05:36 PM

I need some advice. I was driving my 1978 911SC to my parents for Christmas (from florida to SC). I stopped at a rest area, and went to start the car, and it just made a humming noise, and didn't start. I got a push start, and went the rest of the way to their house, and now I've got to get this fixed this weekend.

Does anyone have any advice??

Please help!!

anh911 · 12-24-2003, 05:54 PM

Hot starting problems are common with SCs. What do you mean when you say it was humming? Was the engine turning over at all or no?

eubanksae · 12-24-2003, 07:02 PM

I guess I didn't describe it very well, but it really does just sound like a hum to me, and no, the engine does not turn over.

All that happens when I turn the key is the humming noise, and the engine doesn't turn over at all.

It started just fine, a few hours before. I just stopped at a rest stop to use the restroom, and when I got back in the car, I got the above mentioned results.

The alternator is charging properly, and was just rebuilt a few weeks ago. I also got a new battery at the same time.

Par911 · 02:47 PM

Quote:

guess I didn't describe it very well, but it really does just sound like a hum to me, and no, the engine does not turn over.

Is it a light humming? If it is, it could be the fuel pump that you are hearing which means your fuel pump is working. I would say check your electricals, look at your fuse box. Check for corroded wires. How old is your fuel pump relay? Maybe it's time for a new one. Check the ground wires and make sure they are secured properly to all of the ground points. Another thing to check out is the ignition switch. Hope this steers you in the right direction.

fintstone · fintstone's Garage

If the engine doesn't turn over, must be a starter problem. Check the starter connections. If they are ok, try tapping on the starter with a hammer or heavy wrench and then try starting it. I think you will probably need a starter in the end. If you do put one in, I recommend one of the aftermarket, light-weight, high torque starters...they don't cost much more and are much lighter and more efficient.

xlr8 · 12-25-2003, 06:08 AM

Hi Andy,
I had a similar no-crank problem with my '88 Carrera several months after getting it. I thought I would have to replace the starter, but after reading several posts here I decided to check the wiring thoroughly. My battery terminal connections were clean, but I removed the negative cable to check the connection where it bolted to the body. When I got the cable out of the trunk and into the light I saw that it was not copper colored, but covered with a layer of corrosion. It looked like a piece of green rope! This corroded cable would pass enough current to operate lights and radio, but had too much resistance to pass the heavy amperage required to turn the starter. I cleaned it, re-installed it and have not had a problem starting since. Thanks to the BBS, it was a simple $0 fix. The transmission ground strap could also be a problem area.
Good Luck!

yelcab1 · 12-25-2003, 06:15 AM

1. Check all your ground connections and battery connections first.
2. If it does not start, then your starter needs attention. Either a new solenoid or a new starter.

You can push start it for now and get it rebuilt at home for around $100.

I had a weird no start problem like that for many years with my 84 until I figured it out that the Bosch rebuilt starter had a slightly bent shaft and when it was hot, the gear won't jump out to engage. It took three starter rebuilds to get that fixed. Drove my auto electric guy nuts. He lost money on that one. (Drove me nuts, it took 3 years to fix)

Lesson: Bosch produced crap too.

eubanksae · 12-25-2003, 06:42 PM

I think you're right about the fuel pump being the sound that I'm hearing. I took a quick listen to the source of the sound today. Tomorrow, I am going to check the grounds, and tap on the starter, like recommended above.

Thanks for all the advice, and I'll let you all know the outcome.

on-ramp · 12-25-2003, 06:52 PM

The humming is most likely the fuel pump.

I had the exact same problem on my 83 sc as you described it...it drove me crazy for over 4 months. Finally installed a brand new starter and the problem disappeared for good.

it sounds like your starter has a "dead spot".

makaio · 12-25-2003, 08:07 PM

Good advice from all. Just make sure the car is in neutral before you go wacking on the starter, while someone is turning the key.

eubanksae · 12-26-2003, 01:03 PM

OK, I just got the car on jackstands, and I'm looking at the starter. Am I going to be able to remove this thing without droping the engine/transmission? It looks like the top bolt is near impossible to reach. Is there a trick to it?
I am going back to check my grounds now, but I just wanted to get that question out there.

makaio · 12-26-2003, 05:37 PM

Yes you can do it, & no engine drop is needed. But it can be a PITA. Have you acertained if it is still a barrel nut on there, or a regular hex nut?

If it is a barrel nut it takes a 10mm allen head. What I did is make one of these:

It measures 9 & 1/4" and with a 1/2" ratchet on it measures just under 10". Which is the length to reach it, and be able to loosen it.

RoninLB · 12-26-2003, 05:54 PM

Quote:

Originally posted by makaio

It measures 9 & 1/4" and with a 1/2" ratchet on it measures just under 10". Which is the length to reach it, and be able to loosen it.

cool

eubanksae · 12-29-2003, 07:41 AM

Well, the ground cables at the battery and the transmission have checked out good.

So, I had someone crank the engine, while I tapping on the starter, and it started! It continued to start fine for the rest of the day (on saturday), and I drove it around town, stopping at various places.

On Sunday, I drove back to FL from SC, and to be on the safe side, I didn't turn off the car for the entire trip (just locked the door with a spare key when I had to take a bathroom break).

I got home last night, and after unloading I tried to start the car again, and sure enough, the car won't start again. I guess something happens when I drive for many hours, that is making the starter hang.

Anyways, it certainly looks like I need a new starter, but now I have time to work on it.

Thank you all for the advice!

makaio · 12-29-2003, 07:51 AM

Same problem I had. It ended up being the solenoid, but I replaced the whole starter, since it was 25 years old.

vash · vash's Garage

it is amazing but you can get to the top starter connection by laying under the car on your back, head towards the front. then with the right arm, reach over your tranny. it is right there! there is plenty of room to steady the wrench with your left hand too. chances are it is attached with a barrel nut that is a 10mm allen. so you will need a allen socket. you get into trouble when the stud is too long and it infringes into the space you need for the allen to fit into. i was borderline. turned out that i could fit the 10mm allen socket into the barrelnut, but when i cranked with the rachet it would start to spin out. i remedied the prob, but sticking the allen socket in and using my short 10mm box wrench to break it free. i could keep the allen socket straighter this way. the install, i used a few good washers to prevent the prob next time.