TheSamba.com :: View topic - Compufire 21100 (for 009) on a SVDA distributor

Tue Nov 03, 2009 11:03 am

So just to get it out of the way - I am beetle retarded.

I have a 74 super (my first one) that was running (kind of) and desperately needed a tune up. I got all the parts for the tune up and in a burst of upgrade-crazy also bought a Compufire points replacement module. The thing is, it looks like I bought and installed the one for a 009 distributor, when in fact I have a SVDA. I didn't know how to tell the difference at the time, I simply took the retailer's word for it that I "probably had a 009".

The car doesn't start up, it just cranks and cranks.

My questions are:

Is having the wrong points replacement module enough to stop it from starting up? If so, why? Let's assume that there are no other problems. In this case the carb is getting fuel and everything is wired correctly. The tune-up portion actually went great.

The points aren't in good enough condition to put back in and test. I'm going to grab the correct module, but I want to see if that is likely to be the main problem before I do. Keep in mind the car was running before I "upgraded".

Lesson learned, by the way.

Tue Nov 03, 2009 11:38 am

Get the right points replacement module.

Set the engine to TDC for #1 to fire PRIOR to removing the distributor.

You will need to re-time the engine after installation.

Tue Nov 03, 2009 4:54 pm

When I bought a Compu-Fail for my former '79, they sent me one for a 009. Only difference was a small spacer. They sent me the spacer. Without it, the disc would rub against the module. Also, you will need to "clearance" your rotor (at least I needed to back then). Clearancing means grinding off some of the bottom of the rotor so it sits lower on the shaft (because the spacer and the disc push the rotor up again the cap).

Wed Nov 04, 2009 4:32 am

chrismwood wrote:

My questions are:

Is having the wrong points replacement module enough to stop it from starting up? If so, why? Let's assume that there are no other problems. In this case the carb is getting fuel and everything is wired correctly. The tune-up portion actually went great.

Yes, the wrong module could prevent your engine from running.

The points (and by replacing them your module) are responsible for charging the primary side of the coil and then collapsing the magnetic field inducing a large voltage in the secondary side.
If the module isn't working correctly the coil doesn't fire. That means no spark. No spark and your engine will just crank, and crank, and crank, and crank, and crank...