Having got a Bosch 009 distributor on loan (as it seems to be the only thing my DRLA 36s like to work with at the moment) I spent out and bought a 123 VW R-V (basic) distributor. It's been in the packaging since it arrived, and rather foolishly with 2 days to go until I go off on my weekend trip to Techenders, I decided to get some help to fit it. Opened the packaging.... there's no rotor arm. Seriously?? Do they not come with a rotor arm? Madness. Any other Bosch rotors in my possession just wobbled around, so in desperation we 'borrowed' one from another VW with a Type 1 engine & a 123 dizzy that was in the yard. So my first question: where can I get a 123 rotor arm quickly? Any ideas? I've messaged VW Jim where I bought the distributor from, and I notice on his website he seems to sell them, but I'm still somewhat flabergasted that they aren't part of the actual package. Also, when we tried to time the engine, having set the 123 using its lights, with the idle (900rpm) set at7.5 degrees, the timing advances to 39 degrees at 4000 rpm. Even I know this isn't right. Any ideas? Have I just not found the right curve? Or is the dizzy dodgy? (I had an old genuine Bosch vac advance one that did the exact same thing, so that went over @snotty's fence)
Of course a 123 should come with a rotor arm. I'd nag whoever you bought it from. Had the packing been opened before you tried to install it? Has somebody nicked it? The arm's a stock Bosch part - I've got the number somewhere, or search on here. Set the curve to 0, and time the dissy statically - no gun - using the internal LED. Disconnect the vac sensor if you're checking max advance with a strobe. Can then set it to 28-30* with a strobe if you're in the mood.
Package was unopened. Very odd. And more than a little inconvenient. None of the Bosch rotors that we had to hand would fit correctly - there appears to be an extra 'lip' on the 123 type that presumably makes it a more snug fit. The one that has been 'borrowed' obviously needs replacing. I've messaged VW Jim who supplied the unit. The 123 came set to Curve zero as default. Statically timed using the lights inside. Started the engine and got out the strobe, idling at about 10 degrees gives an advance at 4000rpm of about 39 degrees. Setting the advance to 32 degrees at revs means the engine will hardly idle. Not sure the vac hose was disconnected. Does this make a massive difference? Could this be the problem?
Cool. I'd be relieved if it was summat simple like that. Can't do anything now until thursday morning, but as long as I can make it to techenders I'll be happy.
No, absolutely. I wouldn't drive it like that, I meant getting it fixed and then getting to techenders! If all else fails, the 'on loan' 009 can go back on for a longer loan!
39 degrees no load is 100% as designed on an SVDA. Its vacuum advance adding 11 degrees to 28 degrees. Take the vacuum hose off and it will drop to 28 degrees, or any time you put your foot hard down. Dont worry its meant to be like that. On my dash gauge the advance spends a lot of time 30 plus degrees until you open up the second barrel of the carburettor and it drops back. Top row wide open throttle. Load decreasing as you go down the graph .
And if it is that misunderstanding you chucked away a perfectly functioning OG Bosch distributor. That's a shame.
Ah no, in fairness this was a very old Bosch dizzy (not the one @snotty is thinking of) and it was rather haphazard.... the weights inside it or something like that? It was all over the place. It metaphorically went over the fence. In reality it was sold as not working, to a chap who said he would rebuild it. I'd never chuck genuine stuff that I know can be rebuild. The Bosch that I was using prior to the twin carbs (a very good one, rebuilt by Snotts himself) just didn't want to play ball with the Dells, so I borrowed a genuine 009 as a temporary fix as it was less fussy. The 123 was me wanting to join the cool kids club when I got a bit of overtime pay. Having spoken to various people, I think it's operator error on my part and I'll sort it out tomorrow. The missing rotor arm is a pain, but the person who sells them is sorting it out.
Yes, it's one engine every 30000 miles or so.. and only one of the failures was overheat , and that was timing error, high inlet temperature caused by thermoswitch overheated by heat soak plus wide open throttle. New pistons and cylinders and one head because one piston was lightly melted, and one spark plug thread had a leaky crack. The other ones were rocker arm clip fell off a Vege pile of parts leading to loose flywheel caused by backfiring, so I abandoned it. And the next engine was one dropped valve that jammed the piston.. Neither strangely needing wide open throttle.
