Distributor

[JonPiz]

I have a 1600 engine and it seems the rev counter runs off the distributor. My distributor is shot so can I use a Lucas 25D distributor which has no drive and use an electronic rev counter?

 

[Nickodell]

Yes; I did it. Although Matilda's engine is a Series V 1725, the DPO had installed a dissy from an earlier model, complete with mount having the cable drive to the earlier series tach he had also installed. When I changed my dissy to a Mallory Dual-point, I also replaced the mount with the SV one, and the tach with the proper electronic model. Other than the common error of initially running the sensor wire the wrong way, it worked fine.

 

[alpine_64]

Jon,

if you go the later series tach S3-IV or SV the gauge will look different. The closest match to a SI/II will be the S3/IV as the numbers are the same but it will lack the warning lamps in the gauge and also have a red needle.

 

[JonPiz]

thanks for the advice. I know it may seem a silly question but how and where does the electronic rev counter connect. I could rebuild an engine with my eyes closed but electrics looses me!!

 

[mikephillips]

If you look at the later wiring diagrahm there's a green wire to a post on the back of the gauge that supplies power and a loop in the white wire to the ignition switch through a metal loop on the back that provides the ignition pulse for the gauge to count. Might I also suggest that if you use a later gauge, check to see if the guts can be mounted in your original case to keep the warning lights. You'd need to cut or drill a couple holes for the power and pulse terminals but if it clears the lights you may be able to keep the original look.

 

[Alpine Addict]

I think you would find it easier to use the correct distributor and keep the mechanical Tach drive.

 

[Nickodell]

Jon: If exact authenticity is not important (it certainly isn't with me!) you might do what I did.

My dilemma was actually with the speedometer. The original one crapped out, and I didn't fancy the cost of a rebuilt one. I got an excellent one from a guy parting out an earlier (S III?) model, but it had the wrong dial, of course.

After removing the bezel and glass, I removed the needle by carefully pulling it off with small pliers. You have to secure the body of the instrument and be sure to pull the needle straight up, i.e. at 90 deg. to the dial face.

After this, two tiny screws were removed and the dial taken off and replaced with the one from my original speedo. There was a bit more, such as ensuring that the movement was at the proper place with the needle at the peg.

I guess you could do the same with your tach., by replacing the later dial from an electronic one with the one from your 1600. Then you have the correct dial, matching the one on your speedo., but with the later electronic tach. so you won't need to mess about with gears and cables.

 

[mikephillips]

I'd suggest usiing a pair of curved needle nose pliers to remove the needle. What I do is put them under the needle and push it off by rotating against the dial face. Won't hurt the dial if you're careful and no risk of breaking the plastic pins that hold the dial to the metal sleeve the shaft goes into.

 

[Nickodell]

Mike, that's excellent advice. If you can use one of the dial mounting screws (which are of course screwed into the instrument casting) as a pivot for the pliers, you should be able to pull the needle off in a controlled way.

 

[JonPiz]

Guess what!! Simple answer, I took the drive off the bottom of the old distributor and it fitted straight onto the 25D distributor. So now I have a newer distributor but with the original rev counter drive. Thanks everyone for the input on this one