Hello,
Issue: Have discovered that a significant amount of gas made it's way into the oil on my 1989 FJ1200
Before this:
I winterized the bike six months ago. I ran the bike for about 15 mins with Stabil in the tank, parked the bike, sprayed a bit of fogging oil in each spark plug hole, disconnected the battery and left it on a tender. 3 weeks ago I reconnected the battery, checked the oil sight glass, fired up the bike with hardly any effort, let it get to operating temp, and rode it up and down my driveway, just to see how it fared over the winter. It was running for about 15 mins.
Last night, I went to change the oil and oil filter and the oil reeks of gasoline! It is not nearly as viscous as I would expect. What do I do now?
You buy a new gas petcock. Leaking gas petcocks allow gas to leak into the carbs which then travels into the cylinders, past the rings and into your crankcase. I always watch the oil level to make sure it is not over the sight glass. If it is there is a chance gas has added more volume. When I open the filler cap I always check for the smell of gas and also when I change my oil.
Dave
I vaguely recall a mention of this symptom in another thread, so I googled it a bit and the consensus says don't ride it until you fix it.
Other bikes were being talked about, but as soon as they mention faulty float levels, you know that's an FJ thing. If you're good with carbs, then strip, or if you're like me, let RPM do it right and save yourself embarrassment. Replace oil, replace filter and ride.
This is my best guess. I'm sure others will be able to shine even brighter and perhaps experience informed lights on such.
Just don't ride it
I just read Texas Dave. Yep a leaky pet tap would be an easier fix for sure, so try that first before messing with tricky carbs. Still though, don't ride it, change oil and filter.
What Andy said. Leaky petcock is probably the case as the bike has sat for an extended period of time and even a very small leak will fill the crankcase.
Dave
Since it's a 1989, that eliminates the petcock. For all fuel pump bikes, the fuel flow is stopped with the fuel pump prior to reaching the carbs like the petcock does on the early models.
Secondly, if the fuel pump is leaking, the carbs should hold back the fuel. That is unless your needle and seats are worn or more likely the o-rings on the needle seat has hardened and no longer sealing.
I have genuine Yamaha fuel pumps for a great price in stock. Also new needle and seats and the famous carb o-ring and stainless steel screws carb kits.
I'll have Robert post the links tomorrow.
Randy - RPM
Quote from: racerrad8 on March 22, 2019, 12:45:51 AM
Since it's a 1989, that eliminates the petcock. For all fuel pump bikes, the fuel flow is stopped with the fuel pump prior to reaching the carbs like the petcock does on the early models.
Thanks Randy, I got to this point in my sleuthing as well. I replaced as many of the critical O-rings as I could last year, but I had a reoccurring issue with the #1 cylinder float level. I ended up getting it set properly enough to the point that the bike behaved ok, but I would say for roughly 50 miles, the #1 cylinder was not igniting gasoline. Aside from that issue, there were no standout problems with the carbs that I can point to as a contributing to gas getting in the oil. Could the #1 cylinder not firing for a period of time explain the gasoline in my oil? I've never had this happen with a bike before, and it's quite concerning.
Hey Alex I see you are in Wisconsin. I live in Fond du Lac. Where are you. We should go for a ride somewhere.