04 Yamaha FX Cruiser Engine

yama04

Recruit
Joined
Jul 23, 2012
Messages
2
I bought this used ski with 50 hours on it. It runs pretty well but I suspect something is not right with the engine. It tops out at 43 MPH and 8,000 RPMs. The Learning mode is NOT turned on. I removed the air filter cover and there is a fine oil spray on the inside of the cover and most of the rest of what the cover was above. However, the air filter is dry albeit a bit dirty, (I've ordered a replacement). I ran it on a test run with the filter pulled off and it accelerated quickly up to about 43 but it was just too rough that day to get a good read on top speed. Engine stalls sometimes when I first start it and release the throttle. The engine warning light comes on intermittently on sudden decelerations. When this happens I simply let the ski idle, shut it off for thirty seconds and restart at which point the engine warning is no longer sounding. Others who have ridden this ski say it smells of gasoline and is probably running too rich. Any ideas out there?
 

Ernest T

Petty Officer 1st Class
Joined
Aug 29, 2009
Messages
367
Re: 04 Yamaha FX Cruiser Engine

You have all the symptoms of an overfilled oil tank. The FX has a dry sump oil system. You only check the oil with the engine at operating temperature (its is very hard to get it to full temperature running it on a hose). Never check the oil level on this model with the engine cold, otherwise it looks low and you will overfill the tank. Once the tank is overfilled, the ski runs like crap, fouls the spark plugs, and excess oil is sprayed into the air box through the oil separator breather hose (this is the only way oil can get into the air filter box, so it is a sure sign that the oil tank is overfilled).

My advice. With the engine cold suction out excess oil until it barely shows on the dip stick. Run the engine on the hose for at least 15 minutes, and check the oil level. Or better yet ride the ski for 20 minutes then immediately check the oil level with the ski on the water while it is perfectly level, and the engine is HOT. This will give you the most accurate reading. Adjust the oil level as needed. Shoot for an oil level 1/2 way between the marks. Once you get the oil level right change the plugs, and the air filter. I recommend one of these: http://www.ebay.com/itm/R-D-POWER-P..._Watercraft_Parts&hash=item3f1a064849&vxp=mtr works better than OEM, less expensive, and can be cleaned. Once you do all that you should be seeing 10000 rpms and 53 mph.
 

yama04

Recruit
Joined
Jul 23, 2012
Messages
2
Re: 04 Yamaha FX Cruiser Engine

You have all the symptoms of an overfilled oil tank. The FX has a dry sump oil system. You only check the oil with the engine at operating temperature (its is very hard to get it to full temperature running it on a hose). Never check the oil level on this model with the engine cold, otherwise it looks low and you will overfill the tank. Once the tank is overfilled, the ski runs like crap, fouls the spark plugs, and excess oil is sprayed into the air box through the oil separator breather hose (this is the only way oil can get into the air filter box, so it is a sure sign that the oil tank is overfilled).

My advice. With the engine cold suction out excess oil until it barely shows on the dip stick. Run the engine on the hose for at least 15 minutes, and check the oil level. Or better yet ride the ski for 20 minutes then immediately check the oil level with the ski on the water while it is perfectly level, and the engine is HOT. This will give you the most accurate reading. Adjust the oil level as needed. Shoot for an oil level 1/2 way between the marks. Once you get the oil level right change the plugs, and the air filter. I recommend one of these: http://www.ebay.com/itm/R-D-POWER-P..._Watercraft_Parts&hash=item3f1a064849&vxp=mtr works better than OEM, less expensive, and can be cleaned. Once you do all that you should be seeing 10000 rpms and 53 mph.

Thanks. I initially bought oil thinking it was low. However the counter guys warned me about the process and I checked it at the lake and it seemed high. Rather than add oil I ened up suctioning some out, maybe about a cup. Right now on a hot engine in the water it's at the high end of the normal range. I will take your advice before putting the new air filter in.
 
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