Finding a 1983 harley carb with VOES tube
The original carb on a 1983 XLH was a Kehien "butterfly" type carb as opposed to the current Kehien "CV" type carb. You can find a replacement carb but you're going to look real hard for it and when you find it, it may have the same problem your carb had. So, there are a few things you can do to get around the problem.
One, you can purchase an aftermarket carb and manifold such as an S&S. The S&S Super "E" Shorty card is a good carb but it is a bit big for the 1000cc engine. If you jet it correctly and run an exhaust system with a little backpressure, it will perform well. It will also come with a nipple for your VOES switch.
Two, you can purchase an intake manifold (S&S) or modify your original manifold to provide the vacuum for your VOES. To modify your own manifold, you simply need a piece of brass tubing or a nipple that you can drill the appropiated size hole in the intake and install the nipple. If you have your old carb, measure the nipple and make one yourself. It doesn't have to be made of brass. Drill a hole in the appropiate size bolt and drill and tap your intake for the bolt to screw into it. Don't screw it in too far though and I'd install it in the flange that the carb bolts too.
Three, you can run your bike without the VOES switch. You will need to check the advanced timing on your engine. Set your ignition advanced timing to the mark on the flywheel that represents the "Front Cylinder Advanced" timing mark. This will allow your maximum advanced timing to go to the 35° maximum but no further.
There is a lot of discussion about the operation of the VOES. Depends on what you think it does, advance the timing or ****** the timing. It actually does both. Under light load conditions (high manifold vacuum) the VOES allows your ignition control unit to actually advance the maximum timing on your engine. Sometimes under these light load conditions, your engine may be running at 40° BTDC timing. But, when you open the throttle and put a load on the engine (manifold vacuum goes low) the switch tells your ignition control unit to go back to 'normal" ignition timing of 35° maximum. The purpose of doing this is two-fold. One, it gives you better fuel economy and, two, it prevents detonation or "spark knock". If you disable the VOES by disconnecting it's vacuum source and setting the maximum ignition timing to the "front cylinder advanced" mark (35°BTDC), your bike will run fine but your fuel economy may suffer slightly.
Nov 08, 2009 |
Harley Davidson XLH 1000 Sportster...