Check your fuel filter!

[Chickenman]

How many microns is a paper filter? They now make

Stainless mesh 10 micron

I couldn't get the Edit function to work in my posts before. Fixed now.

10 Micron is fine for Petrol EFI, but it is not the only determination. You have to watch the flow rates. Pleated Paper element filters have a high surface area which enables them to filter out very small particles while maintaining proper fluid flow rates. That is something that must be considered when purchasing any filter. Most filter manufactures now use a standard called Beta Ratio Testing: This is a good Tech Article from Baldwin Filters ( One of the largest filter manufacturers in NA ) , Click on the PDF's at the bottom of the page:

Baldwin Filters | Product Highlights

Actually SS Fuel Filters ( good ones ) now come in 1 Micron sizes which is more than adequate for Petrol EFI. But decent ones are not cheap. SS meshEFI filters for petrol with adequate filter area is going to cost between $125 to $160. And then there's the question of efficiency rating, IE: if the micron rating is rated " nominal " or " absolute ". It's a big difference as per the article above.

Canton makes excellent products. but I have no idea of their efficiency rating:

https://www.cantonracingproducts.com/product/25-910/25-910----CM--15-FORD-EFI-INLINE-FUEL-FILTER-OE-FITTINGS/

IMHO, there is absolutely nothing wrong with paper element filters. As long as you get quality products..... AND stay away from fuel with Ethanol contents higher than 10%.

Edited November 2, 2014 by Chickenman

[FastWoman]

The problem with staying away from fuel with ethanol > 10% is that there are no guarantees what comes out of the pump.  Here in the US, it is illegal for stations to sell gasoline with > 10% ethanol, so one would think that would ensure we don't actually buy and burn any.  But the reality is that we have these huge subsidies supporting the ethanol scam, and businesses are incentivized to dilute their gas with ethanol.  So by the time the gasoline has passed through a few hands, it may have been cut with ethanol a few times. 

 

I suspect gasoline is available in 3 basic mixes in the real world: 10% ethanol, 19% ethanol, and (rarely) 27% ethanol.  If you're familiar with your local supplier, you can probably avoid > 10%, but if you're traveling or in an unfamiliar part of town, you have to be careful.  I try to find fuel that has come as directly as possible from the refiner, passing through as few hands as possible.  There's a local outfit where I try to buy all of my fuel.  It feels a bit like a truck stop, and they even sell 0% ethanol gas there if I want -- also E85, biodiesel, and propane.  I have every confidence they buy direct from the refiner, and their E10 is really E10, not higher.  (Note: My Z is now tuned to E10 and doesn't run as well on E0.  I get the E0 for anything of mine with a carburetor -- boats and lawn equipment.)

 

I suspect these are good signs that the gasoline has passed through as few hands as possible:

 

• Name brand gasoline.  (But note: Shell gasoline, for instance, doesn't necessarily come from a Shell refinery -- probably doesn't.  However, it's Shell's reputation that suffers if you buy bad gas at that station.)
• Large station that sells only fuel -- where you can't buy a drink and a hot dog.
• Offers lowest price -- suggests fewest wholesaler markups (however, keeping in mind that a wholesaler might profit simply through the collection of an incentive for watering down the gas).
• E0 gas is available, even if that's not what you want to buy.  (I imagine E0 is only available directly from a refiner.  Note: E0 at the pump is illegal in some areas -- banned where I used to live, in just the next county over.)