I've been premixing for more than a year and I was wondering what effect it does to the stock fuel filter? I noticed on my car since i started to premix I had to change the fuel filter more frequently that before. I put about 11k miels on it and it was already clogging up. I tested this out with a wideband and it was running very lean. I got a new fuel filter and it fixed the problem. Has anybody experienced this? Btw all were OEM filters.

 

its not terribly uncommon for fuell gumming problems to occur on engines that run premix all the time (clogged injectors, filters etc). after all 2- stroke oil is thiker than gas and the feul system wasnt designed for it either. but that doesnt meen its not good idea.

just dont let the ratio go heavier than 100:1, and run a bottle of good fuel system cleaner (i prefer techron) through it every oil change and you should be fine, or at least be able to get back to regular service intervals on the fuel filter.

 

Hey, that's a good question...
My car has leaning problems, especially around 2kRPM to 4kRPM, and I always thought the fuel injectors were clogged - I run 4x720's.
I can't get my SFC-HyperR to adjust the fuel enough for it to run nicely.
The car has been sitting around for a while at one point...
I'll try and replace the fuel filter to see if this is the problem.

I do run pretty heavy ratios...
16oz. per 13 to 14 gallons, so it's more like 100:1 or slightly richer than that.



-Ted

 

good question, yes, but i don't think that it poses any real risk on the fuel filter. how i see it is that once dissolved in gasoline, the oil particles are not large enough to be filtered by the fuel filter. there is a certain micron filtering specification, and i don't think that the oil would be big enough.
i do know that when using oxygenated premixed fuel, sometimes an emulsion can form. this is very bad since you get 2 effects. one is that you may not get any lubrication as all the oil will seperate. the other is that the emulsion will clog up the fuel filter.
as this is not possible without the presence of an oxygenator, i don't you have to worry about this happening.
also note that the premix ratio does not determine the dissolved particle size, just simply the parts per million (PPM) concentration of the oil particles. a simple chemistry course will tell you this...however it could be said that this would increase the frequency of oil particles going through the filter.

so here are my suggestions:
1) obviously use the proper premix ratio
2) get a good performance fuel filter, change that regularly
3) keep the tank full when the car is sitting or in cold weather; this will reduce the amount of moisture in the gas tank and help prevent the mentioned oxygenate (water) that may produce emulsive agents/particles
4) do not use blended gas, such as ethanol, since it contains oxygenates that will attract moisture

 

that doesn't seem to be that heavy of a ratio if you are running just straight premix. in fact, most premix oils actually state that you should use a ratio of at least 100:1...i know we are not talking about a boat or lawnmower engine here, but using anything higher than 100:1 may lead to uneven oil distribution in the gasoline...

 

I'm just wondering about this, since i started to premix, I had to change the fuel filter more frequently. I wonder if premix had anything to do with it.