Fouling plugs? Update 9/2/08
 

Hey guys, long time no talk...

Finally I took the boat out for a shake down cruise and a little water skiing with the kids. For the first few runs the motor ran top shape topping of at 42 MPH on the GPS. After many stops and take offs and lots of idling, the motor started to idle a little rough and ended up losing top speed. I believe I fouled one plug and for a while it ran on 5 pistons only.
My hope is that I just fouled one plug due to all the excessive idling, after all, I pre-mix my gas at 40:1 ratio which may be a little to much.
When I first got the boat, (Fall of 2006) I did a decarburization using the “Seafoam” method and the motor ran perfectly fine for the entire 2007 season. Have any of you experienced problems similar to these, pre-mixing at 40:1 ratio?

Thanks

Joe

I mix 50:1 never had a problem.

Thank MJ

I'm going to do a compression test and a decarb job using seafoam. Will report back.

Thanks

That 150 looper you have WILL foul plugs on 40:1 at low RPM's, not much you can do about it. The VRO ran them at 100:1-150:1 at idle to prevent plug fouling, but they would go to 50:1 at around 2000 RPM's and then to 40:1 above around 5000 RPM's. I would use a semi synthetic like PENNZOIL offers and mix it at 50:1. A regular dino oil at 50:1 will still foul plugs more frequently than a synthetic blend or a pure synthetic.

i used to use 100-1 amsoil synthetic blend in an old cross flow. Amsoil designed it to replace a 50-1. It worked real good, the engine idled good, but it didn't smoke enough for me, I always wondered if I had mixed the oil with the gas, or had mixed it correctly. Engine never had any issues from running it.

I’m starting a 50:1 mix ratio until I use all my Quicksilver oil, after that I’ll look into the semi or full synthetic oils. For safety purposes, I do quite a bit of idling when fishing at or near some rips (Race and the Gut) If I could cut back on some of the white smoke it would be great…

Thanks

Joe

PENNZOIL vs QUIKSILVER will definately cut down on your smoking some. QUIKSILVER is a good oil, but it smoked ALOT in every engine I've run it in.

Thanks
I added gas to the tank so I stayed closer to the 50:1 mixing ratio, last Sat. I went fishing with my neighbor and his son, we burned about 20 gls of fuel drift fishing and moving around, overall, I noticed a little less smoke and no fouling occurred.

One thing I notice was the lack of top speed, the max I could do was 33 mph.(usually 42 mph) Can’t figure out why…:head:

Prior to the trip, I installed a brand new set of Champions set at .030 gap. Did I buy bad plugs?


Thanks

Joe

You may have been running lean before at WOT. 40:1 will actually lean your fuel mixture out vs 50:1. At 40:1 your fuel is denser and slightly thicker which makes it go through the jets slower. 50:1 will fatten your top end out slightly.