Gazoo,
Look at what I went through:
https://www.sl113.org/forums/index.php?topic=26124.0May look similar to your situation. It is about verifying if IP delivers the same amount of fuel to all cylinders. Does not matter how much fuel, what was important was the amount in given cylinder vs. the others.
It is easier than it seems to determine that.
Starting from the end to the beginning.
Injector: if you have a new one, you may replace it and see. If you do not have a new one, swap it with another one and see if the effect follows the injector. While doing this, you may determine wich cylinder is weaker by pulling ignition leads from plugs.
If the issue is not the injector, which was my case, I measured amount of fuel delivered by fuel lines of the suspected cylinder vs. other fuel lines. You just unhook the fuel line from injector, you may take a small syringe, plug the needle hole, crank the engine a bit so that fuel appears at the end of the fuel line, put the fuel line into the syringe, run engine or crank engine for, say 30 seconds, measure amount of fuel. I got 20-30% difference between suspected cylinder and other cylinders. A lot.
Then my suspect was the fuel line - they may get clogged. I had a short piece of fuel line with one connector. I connected it to the IP. Again, cranked engine, saw fuel at the end of the short line, put it in the syringe, ran engine for 30 seconds, measured how much fuel i got. It was the same amount as at the injector end of the "usual" line. So line was not clogged.
You have to remember that the cylinders on the IP are numbered vice versa to cylinders numbering in the engine.
My next step (some say unnecessary) was to check the check valves - by swapping two of them around. I got the same effect.
When you have check valves out you can check on piston movements. My pistons were moving ok. If your piston of the suspected cylinder is not moving, there is achance you can make it move.
At this point it was clear - the IP was not properly calibrated between cylinders.
The two items you need to have to look at pistons and check valves (if you choose to) are the check valve puller and the check valve seals. The seals are not easy to find (I found them on amazon).
You may decide to send your IP for calibration already when you confirm it is not delivering the same amount of fuel through all sections. But the temptation is to see if the pistons are moving because there is a chance you can make them move yourself if they do not. If the check valve is bad - you could replace it yourself too, which also is tempting (but more experienced members are saying that the check valves usually do not go bad).
You will find all the info you need on the forum - tools, procedures, etc.
Another point here: if you get to the point when you decide to remove your IP - please check if it was timed correctly. If the timing is reversed 180 degree the engine will run, but unevenly and may be distributing fuel to cylinders in the wrong moment. Do it as the first thing as you get the IP out - are all the marks aligned properly? Info on timing is also present on the forum or in tech manual.
