Measuring Dwell Help

[81 SC Ray]

Hi All,

Please help me with some technical questions.

We are talking about this car:
1981 Porsche 911 3.0 Liter - stock except SSI exhaust.

I want to know if I am running lean or rich. As I understand it, I am supposed to test that by putting a dwell tester on a test point and read a value. I have a Bentley manual, but, it is not descriptive enough. I have a quality multimeter, what symbol on the meter represents the setting I need to measure the value and compare it with the values in the manual.

Thanks so much - forgive my ignorance, but, we all have to start somewhere!!


Oh yeah, I have to change my starter - any advice on getting to the top bolt?? :-)

Thanks all.

Ray

[tharbert]

I don't think a multimeter has dwell measurement capability...maybe some automotive ones do? A dwell meter measures, in degrees, the portion of a circle where the circuit is closed. Maybe an analog ohm meter would give you something useable? I'm sure someone with an 81 will chime in...

[cmcfaul]

To get the bolt off the top of the starter is easier than you think, but messy. You have to lay under the car and bear hug the transmission getting to the bolt from the top. Once you commit to ruining a shirt it is easy to find and to apply leverage.

Good luck,

Chris
73 911 E

[psalt]

Ray,

Search this site for CIS lambda and you will find all you need. A digital dwell meter will not work, you need an analog meter.

Paul

[James Brown]

Got to go old school on this one. Check craigs list.

[BK911]

I searched for:

+cis +multimeter

this thread will get you started:

cis multimeter voltage

There are many others.

[81 SC Ray]

Fellas,

Thanks for the help. I will research all - new starter today - wish me luck!!

Ray

[Walter_Middie]

Ray,

I have modern multimeter with a dwell setting on it - so they do exist.

Chris is correct about the bear hug method. I lay on my back, under the car with my feet sticking out the back. Left arm goes over the right (or passenger) side of the trans, and my right arm goes the long way around the left side of the transmission. Look at your new starter, and you can see where the top nut is. I use a 3/8" ratchet with a 6" extension and a 10mm Allen socket. I can have my starter out in a couple of minutes - I've had recent experience with this.

Pay attention to where the wires are attached to your old starter before removal, and don't forget to disconnect the battery first.

Best of luck.

[LUFTMAN]

I have a plug i can send you to plug into factory test connector in engine compartment by left fuse box you will need a digital meter with a duty cycle to check on off ratio of frequency valve regards tom

[81 SC Ray]

Hi All,

Sorry to have turned this post into a two part thread - bad form - I know.

Great success at replacing the starter today. I have hugged my transmission more than my wife today.

Tom, I have PM'ed you - thanks for your kind offer.

One last note - most of you probably already know this, but, as a starter begins it journey down the path of failure, an early sign is "heat soak". So, as your starter gets warmed by the engine heat - its impedance goes up - and when you turn your key after you run into the store for 2 minutes, absolutely nothing will happen. After you wait 20 minutes for the starter to cool down - it works. That is what my starter was doing. Eventually, it will fail for good.

Have a great night everyone.

Ray

[Bob Kontak]

I just bought a dwell meter at Advance Auto for $39 US.