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Nozzle
I'm having non-starting issues (used to be only hot but now it's both cold and hot) with my 1973 2.0 and Scotty B suggested the electrical connections to the positive battery post may be part of the problem. So I thought I'd start by cleaning up these connections or at least replacing the battery cable with something more stock to begin trouble-shooting. The problem is I'm not sure what these connections are supposed to look like. So does anyone have any good pictures of how these connections are supposed to be arranged?

Here's what mine currently look like:

Click to view attachment

Many thanks,

John
ClayPerrine
That is about average for the wiring on a 914. The ends of the main power feeds have corroded over the years and been replaced. The ones there look fairly good, with soldered connections on them.

I would replace the main battery cable. I never liked the clamp on ends, and you can get a larger gauge wire with a factory installed end on it fairly cheap.

What are the no-start symptoms? Maybe we can help with the troubleshooting.

mrgreenjeans
Interesting pic......

The good thing is, all this can be replaced with OE Porsche parts , I do believe all are still for sale. I know the ground strap, which is a real critical link in this , was readily available for around 20 bucks not that long ago, and there is a diagram they should have on the PET program you can look at. Get friendly with your Porsche parts guy at the counter and have him spin the monitor around or take a copy of the pic in the PET.

Also, if you have handy a Haynes manual, there should be a pic in there.

I also found , if a fully charged battery isn't in the car, it will hinder starting. It will spin it but not fire off. Check the load on the battery too and recharge / replace if there is too much draw down.

The ground strap where it attaches to the body , needs to be very clean....think shiny metal touching shiny metal, to make a proper and efficient ground. Rarely have I seen clean areas around the battery box in these cars, but this is critical.

And the tangle of leads going into your postive cable needs to look like the diagram, not like it does. Not trying to be hyper critical, but too much birds nest here.

Clay is right, factory spec ends are the way to go here. Not only look better, as in OE, but they WORK.
Tom
That definately looks bad. Someone didn't have the correct crimpers when attaching the ring terminals. It may be OK electrically, but certainly could be replaced for piece of mind. This is only one area where you could be having problems if you are having the starting issues. Try the search for hot start problems, as there are many and lots of ideas to correct this problem.
Just for your info, those 4 large red wires go to: the two larger to the key switch and fuse block under the dash, the two smaller ones to the relay panel in the engine compartment and are UNFUSED!! Always disconnect the battery when working on your electrics.
Here is a pic of my positive battery connection, not OEM, but works perfectly.
Tom
Nozzle
Thanks for the good info guys. The car has had hot starting issues since I've owned it for the last four years. Checked the CHT sensor lead and it seems to be in spec so I figured next I'd start checking all the electrical leads and that's when it stopped starting even when cold which is a first. Starter is getting power and the fuel pump spins up fine but the starter just doesn't engage anymore. Gentle hammering and jumping with screwdriver don't seem to work either. So before replacing the starter which looks fairly new I thought I'd start getting the power connections in good shape before going further.

My problem is none of the engine compartment pictures I've seen on this site have good shots of the positive terminal wiring. I've seen online parts suppliers offer power cable replacements but I'm not sure how to tell if I'd be getting closer or farther from a reliable solution with these parts or if the spaghetti connections I've got now are even close to a factory spec setup.

Anyone out there with battery terminals that their particularly proud of that would like to share..? biggrin.gif
Nozzle
QUOTE(Tom @ Jan 8 2012, 03:21 PM) *

That definately looks bad. Someone didn't have the correct crimpers when attaching the ring terminals. It may be OK electrically, but certainly could be replaced for piece of mind. This is only one area where you could be having problems if you are having the starting issues. Try the search for hot start problems, as there are many and lots of ideas to dcorrect this problem.
Just for your info, those 4 large red wires go to: the two larger to the key switch and fuse block under the dash, the two smaller ones to the relay panel in the engine compartment and are UNFUSED!! Always disconnect the battery when working on your electrics.
Here is a pic of my positive battery connection, not OEM, but works perfectly.
Tom


Very nice Tom, thank for the picture. I noticed that you only have two instead of four red lines going to the terminal. Are you not using two?

Although it's not clear in the picture I attached the red wire at the top of the picture is hanging on by a thread which is why I'm thinking I need to really resolve that mess before going further.
montoya 73 2.0
Looking a little closer you will see two wires per connector.

Tom made a kit which you can see mounted on the battery tray and it also cleans up the area.
red wire to battery kit...
Tom
Yes, Montoya is right. I used all 4 wires. Just put one large and one small in each ring terminal and then lightly soldered the ring terminal at the end of the wires to ensure a good connection. I used a 10-12 gage ring connector that both wires fit in kind of tight. Since that picture I also used a nylon tie to tie the 4 wires in the heat shrink to the large battery cable. This ensures there is little to no strain on the electrical connection, which is why your wire has only one small strand of wire left making a poor electrical connection. This type of connection is the bane of electrical trouble shooting as it will give you OK voltage readings when not under load, but will not allow sufficient current to operate the load.
If I understand you correctly, the hot start issue has plagued you for some time. If so, you probably have a defective key switch due to arcing of the contacts. With no hot start relay installed, the initial solenoid current is 35 amps. As soon as the Bendix throws the starter gear out and makes the electrical contacts inside the solenoid, that current drops to about 10 amps. When you release the key switch, a back EMF causes an arc across the key switch contacts. Someone here once posted some numbers they had had someone take with an O-scope. The back EMF was in the 350 volt range and this was for a properly operating system. If your starter solenoid is not closing, then the back EMF is going to be about 3 times that voltage, so more of an arc, which will accelerate the deterioration of the key switch contacts. That is probably why you are now having the no start issue even when cold. I put a hot start relay on mine even though I was not having any starter issues just to save the key switch contacts.
Hope this has been helpful,
Tom
yellowporky
Are you having cranking issues or does it crank and not fire? I had 74 converted to carbs by a po there was a ground issue so it had problems with hot cranking. Adding an extra ground strap fixed this issue.
If it still has fuel injection clean all of your grounds and replace the ground straps as a good first step so save trouble shooting time.
good luck
Mike Bellis
Don't forget that battery cables can go bad without looking bad. The only way to know is a voltage drop test or open up the cable to inspect for corrosion. Either way a new cable is good insurance.
mrgreenjeans
QUOTE(Nozzle @ Jan 8 2012, 05:33 PM) *

Thanks for the good info guys. The car has had hot starting issues since I've owned it for the last four years. Checked the CHT sensor lead and it seems to be in spec so I figured next I'd start checking all the electrical leads and that's when it stopped starting even when cold which is a first. Starter is getting power and the fuel pump spins up fine but the starter just doesn't engage anymore. Gentle hammering and jumping with screwdriver don't seem to work either. So before replacing the starter which looks fairly new I thought I'd start getting the power connections in good shape before going further.

My problem is none of the engine compartment pictures I've seen on this site have good shots of the positive terminal wiring. I've seen online parts suppliers offer power cable replacements but I'm not sure how to tell if I'd be getting closer or farther from a reliable solution with these parts or if the spaghetti connections I've got now are even close to a factory spec setup.

Anyone out there with battery terminals that their particularly proud of that would like to share..? biggrin.gif


Nozzle:

Wish I was more adept at being pc savvy and I would show you what our original 60,000 mile cables look like going to positive. They are somewhat similar to the arrangement on Tom's pix, but have quite a bit more of a factory spec. look. The clarity of purpose and meaningful design of his arrangement is what's getting the job done here, so if you aren't competing for Concours awards and risking a docking of points, do a similar gig and you should be all tidied up and good to go.
Think: absolute perfection and cleanliness on the ground strap to body connection, and with the 4 red leads bundled like Tom's , you should have this commonly overlooked trouble spot good to go.
Best wishes.....
ps...maybe contact Pat Garvey as to a good pic on how a concours looking arrangement should appear. He posts on this site alot. Can't remember his handle, but has the avatar of a pig snout snorting.
mrgreenjeans
Forgot to add that Tom is dead on about the issue of the key switch going bad and not enabling a crank/ fire mode.
These switches when going south will allow the car to crank and crank and crank and not ever catch or allow ignition.
A simple changeout ....well not all that simple.....will totally transform the ignition performance of a poorly starting car. Plastic internals to the switch assembly are easily sourced on ebay or your local Porsche dealer. Get the VW / Porsche part for longevity sake.
Look for the plastic , white housing on the internals of the swith to have a crack and allow the piece to not make proper contact . Cold weather, constant overuse of the switch....read high mileage cars, will cause this to crack and separate just enough to squelch start mode.
Good luck.
windforfun
Cut them all off. Replace with similar lugs without yellow plastic. Don't crimp solder tinned wire. Crimp & then solder or don't crimp & then solder. Nice hot solder joints with clean surfaces. Use black shrink tubing instead of yellow sleeves. Time for a new starter cable. My 2 cents.
aharder
QUOTE(Tom @ Jan 8 2012, 02:21 PM) *

That definately looks bad. Someone didn't have the correct crimpers when attaching the ring terminals. It may be OK electrically, but certainly could be replaced for piece of mind. This is only one area where you could be having problems if you are having the starting issues. Try the search for hot start problems, as there are many and lots of ideas to correct this problem.
Just for your info, those 4 large red wires go to: the two larger to the key switch and fuse block under the dash, the two smaller ones to the relay panel in the engine compartment and are UNFUSED!! Always disconnect the battery when working on your electrics.
Here is a pic of my positive battery connection, not OEM, but works perfectly.
Tom


Tom,

Can you give us some more detail on your set up? Looks like the 4 Red leads are going through a fuse box.
Does each lead have its own fuse? Does the main to the Started have a fuse?
What amps fuses? I think I see a 20. dry.gif
I like the set up and would like to follow your lead for mine. biggrin.gif
Tom
Aharder,
Here is a link to the fuse block kit thread.
http://www.914world.com/bbs2/index.php?sho...=141317&hl=
And one for a "hot start relay" thread.
http://www.914world.com/bbs2/index.php?sho...=150398&hl=
Both, in my opinion very good mods to the electrical system for our cars. Both are working fine on mine. For more info on where to buy the parts, check out DELCITY electrical. It is much easier and cheaper do these parts in bulk and provide "kits" for each application. Some parts need to be purchased by the hundred, such as ring terminals and spade terminals.
Tom
914werke
The original terminal pinch bolt was a special block headed affair which those 4 could be secured with a 10mm into that block ...not sure if you can still get a replacement anymore.
aharder
My Pinch Bolt is in great shape so I'm looking forward to doing
this mod. biggrin.gif
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