Hello, let me first say I'm new to forums and new to PWC in general. I recently purchased a 1999 Yamaha 1200 XL Limited. I was told that it had been serviced and the #3 cylinder had been replaced because an oil line came off. Also the Cat had been removed and the D plate put in place. I took it out and rode it a few times after I purchased it. It ran great. I couldn't have been more pleased with it. Ran smooth, good controls and got it up to 55-60 mph.
I'm very familiar with boats and I noticed that the oil level in the tank hadn't gone down much at all (Been pre-mixing the gas because the previous owner told me that was recommended by his mechanic until he was sure the oil pump was working). There was also some oil in the bottom of the hull as well that we couldn't locate the origin, but it didn't appear to be coming from the engine. So I decided to take it in and get the oil block put on it and switch it to premix. Had the petcock replaced too as it appeard to be stuck in the "on" position, and a new battery put in.
Got it back from mechanic the other day and took it to the water. Cranked fine. Then I went to take off and it was extremely sluggish. Wouldn't go over 35 mph. It was idling rough as if it was missing (noticed a bubbling sound too coming from the front of the ski, hadn't heard that before). And something else that seemed very odd to me, it was no longer stable. It felt as if the rear of the hull was full of water (which it wasn't) and I couldn't control it. Put it back on trailer and took it back to mechanic.
I got a call and they advised me that they did a compression check and found everything good. Checked the impeller, it was good. The steering controls were good. They couldn't find anything wrong with it but they did take it out and confirmed that they noticed the same issues I did.
Sorry for the long posts but I tried to describe it as best I could. Any ideas? could changing it over to premix have caused any of these issues. Any help would be greatly appreciated.
Have you replaced the spark plugs? Typical for them to foul more easily with premix, especially right after the conversion. Bubbling sound from un-burnt fuel/oil getting injected into the cylinder that has the fouled plug.
What ratio are you running? On that ski it should be 50:1. Running too rich could slow things down, foul plugs, etc..
There should be absolutely no effect on stability, so I can't explain that.
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2008 Yamaha FX HO Cruiser
2010 Hurricane Sundeck 2100
Im running 50:1 even though they tried to tell me to run more rich. The spark plugs looked fine with the exception of one that was loose in cylinder 1. Noticed some oil around the threads of the cylinder but that was before I had it switched over and it was running fine then.
Wait are you running both the oil injection and pre-mix? That's how I understood it, anyways you can't do both. That's probably why it's running poorly. The most pre-mix you can run with the oil injection is 100:1 (and that's if you wish) Personally I don't see any reason to. Sooner or later you're going to have to trust the oil injection system. So replace your spark plugs, fill it up with straight gas, and go ride.
No, Its all pre-mix now. I put a small amount of oil in the tank before I had it swapped over, just to make sure there was some in the event it quit pumping. This was only for a couple of tanks tho and not a 50:1 ratio.
Need advice on PWC problems.
That's how I understood it, anyways you can't do both. That's probably why it's running poorly. The most pre-mix you can run with the oil injection is 100:1 (and that's if you wish) Personally I don't see any reason to. Sooner or later you're going to have to trust the oil injection system. So replace your spark plugs, fill it up with straight gas, and go ride.
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