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In this post I want to show you how you can adjust your Puch ignition (step by step ) and in the most accurate way possible. This post is beginner friendly, so no prior experience needed to start adjusting your Puch ignition today.
This post can both be used for mopeds using Bosch breaker points based ignition or an electronic ignition (like the Vec Electronic Ignition Coil).
WHAT YOU’LL NEED – MATERIALS
Working on engines and ignitions means you need to be able to work as precise as possible to get the best performance out of your Puch engine and not damage it.
What you’ll need:
- A piston stop
- A timing light
- 12V battery
- A Bosch flywheel puller
- Feeler Gauge
- Optionally: a micrometer
- Black marker
Using a Timing Light for Ignition Timing
Why use a timing light?
I’ve been working on Puch mopeds for years and NEVER did I succeed to get by ignition timing at the right point, namely: 16-18 degrees before TDC (if you don’t know what this mean, don’t panic, we’ll explain it later in this post.
This was the case until I got myself a timing light. A timing light is an absolute must have and a must use since it allows you to adjust your ignition timing really accurately. Let me be clear on this, THEIR IS NO OTHER WAY TO ADJUST YOUR IGNITION TIMING ACCURATELY!!!
I know that with this statement, not everybody will agree. That’s fine. Until recently I also always tried to adjust my ignition by “eye-balling” when the breaker points opened and never did I had my ignition timing set accurately. Just use a timing light, they’re not expensive and you’ll be happy afterwards with the results.
5 STEPS TO SET YOUR IGNITION ACCURATELY
Step 1: adjust your breaker points at 0.35mm
If you have breaker point based ignition, I advise you to use a feeler gauge and set the points at 0.35mm. I always use 3 blades. one of 0.30 mmwhich should get through the points without any resistance. A 0.40 mm blade which doesn’t get through, unless the blade opens the breaker point and last but not least, a 0.35mm blade which should get through the breaker point with a little resistance – a little rub ( It should not push the breaker point open).
How to adjust Puch Bosch breaker points? If you don’t know how to adjust the breaker points, you can find more info here.
Step 2: Find Top Dead Center (TDC)
If you don’t know what TDC is, it’s the furthest point of a piston’s travel towards the spark plug. After this point it goes back down towards the engine case.
This is a pretty easy step but keep in mind to work as precise as possible, each mm counts. For this step you’ll need a piston stop (you can get one here).
- Insert the piston stop
- Turn your flywheel in the normal direction (the running direction) until it hits the piston stop. The goal is to find the find the highest point that your piston travels, so the piston stop should only be a little bit in the spark plug hole).
- Make a mark on the flywheel and carter as shown on the following picture. Let’s call this the Ignition mark.
- Turn the flywheel in the opposite direction and make a mark on the flywheel where the ignition mark is located (see next picture, the left mark).
- Measure the distance between the two marks and draw a third mark right in the middle of the two other marks. This is your TOP DEAD CENTER mark.
Step 3. Mark the pre-ignition point.
Option : working with 16-18 degrees
Now for stock Puch engines (e50) it’s advised to set your ignition timing on 16 – 18 degrees before TDC. Given the fact that a Bosch flywheel used on the Puch engines has a circumference of 360mm, we can state that 1° = 1mm.
- Measure + 16mm from your TDC mark and make a new Mark (in the running direction).
- Measure + 18mm from your TDC mark and make a new Mark (in the running direction).
As from now we will refer to pre-ignition marks meaning the 16 and 18 degree marks.
Small note: some engine cases / flywheels already have the TDC marked originally. If this case it’s clear you don’t have to do the above steps.
Option: working with mm pre-ignition
to be added soon
step 4. Check your current Ignition Timing with a timing light
The pre-ignition marks (the 16° and 18° markers) are drawn, so it’s now time to check how far or how close we are from our desired ignition timing point.
Common Error! Make sure that the connector on the sparkplug cable is set in the right direction. There should be an arrow located on the sparkplug cable connector showing you the direction to the sparkplug. If this is not set accordingly, you’ll get some strange results when checking the timing.
- Take the 12V battery
- Connect the timing light to the battery
- Connect the timing light to sparkplug cable (see picture)
- Start the engine
After all plugs are connected, it’s time to start the engine and hold the timing light towards the flywheel. Now you’ll see how close you’re at the desired ignition timing point. COOL ISN’T IT!
How does a timing light work?
How does it come that with a timing light we only see our marks? A flywheel rotates by thousands of rpm, way to much for our eyes to follow. The timing light only gives light when your spark plug fires. So each time the light flashes is when the mark is near the case mark, making it easy for us to adjust our ignition timing.
Step 5. Adjust your base plate
Based on the previous step, there are 3 possible outcomes.
- Flywheel mark left of case mark: In case of a right turning flywheel: if you notice that the mark on the flywheel is located on the left of the case mark, this means that your ignition fires to early. You’ll need to set your base plate to the right (a few mm).
- Ignition mark on the right of the case mark: In this case your ignition is set too late. Solution: turning the base plate to the lift, will give you advanced ignition time.
- Flywheel mark hits the case mark: Hoeray, your igntion is set accurately! Enjoy the driving.
IGNITION TROUBLES AND SOLUTIONS
Here we want to discuss some common issues and how to solve them. If you have an issue that is not listed, feel free to send it to us so we can take it in the list.
Help my pre-ignition marks are way off the desired ignition mark!
Reason one: new breaker points
This one I had myself. As you can see on the picture, my marks where way off and I just couldn’t get it closer to the ignition mark. Now this is common issue and is in most cases easy to solve. You’ll need to try new breaker points,
IMPORTANT! When replacing breaker points, ALWAYS buy the original ones, no replicas. You’ll only get trouble with the replica’s and you’ll need to replace very often. Just buy the BOSCH Ignition points with cable.
Reason 2: bad breaker point adjustment
If you got quiet a lot of distance between the pre-ignition marks and the flywheel mark, this can also be caused by a non-accurate breaker point adjustment. Have you adjusted your breaker points to 0.35mm? If yes, go back to reason 1.
Help I can’t set my base plate anymore later?!
It is possible that the ignition mark and case mark are almost lined up and you only need to set the ignition a little later. However, your base plate is already completely to the left.
I also had this problem, My ignition fires at 18 degrees, or 1.3 mm pre-ignition. Now this is “OK” but it’s not at its best . Now I already turned my based to the right and there is no more margin left.
What should you do? It’s common error and easy fix. Just widen up the 3 holes a little so that you can the base plate further.
Please note that if you are way off, let’s say you’re missing like 1cm, the issue is to be found in the breaker points (see above).