Fuel Filters

[El Camexican]

Since getting down here I’ve noticed that fuel filters plug up faster than they did up North, but the dirt bikes and trikes in particular seem to get a lot of nasty material in the float bowls even with inline filters.

I tried a glass filter (duh) that broke when a rock hit it 10 miles into a trip. Then I started using these, but I still find a bunch of junk in my float bowls after just a few hours of use. This one has 400+ hours on it and there’s hardly anything trapped in it



So about 6 months back I remembered the filter my Dad’s old 1972 Moto-Ski had. It was a Tillotson in-line filter that you could open and clean and put back together with a single screw. It also was adjustable if you wanted to angle the inlet, or outlet. I searched eBay and there were some NOS units still out there, so I grabbed a couple and put on on my long range bike.

So last night I opened the carb to clean the bowl as I have been doing every 20 hours or so and it was clean so I opened the Tillotson filter and this is what I found.



Can’t say enough good about these things. Put the second one on the back up bike and found a dozen more on eBay. I’m putting them on everything I own with 1/4” line.

[floydechoes2000]

Wow, I forgot all about those! Great tip, thanks for sharing!

[azhondagrl]

Definitely need to put these on like............everything I have(currently using the little plastic ones like in the first pic). Can you link the ebay listing or just let me know what they're called to search for them myself?

Thanks in advance!

[El Camexican]

You have to scroll a bit after searching "Tillotson Filter" but they're in there.

https://www.ebay.com/itm/10-Nos-Till...4AAOSw7W5XOKht

https://www.ebay.com/itm/2-Nos-Tillo...!-1:rk:42:pf:0

https://www.ebay.com/itm/Vintage-NOS...dVT:rk:22:pf:0

[fabiodriven]

Oh man I just had a flash back when I saw that picture. My 1970 Nordic 399 had a Tillotson diaphragm carburetor with a filter like that which screwed right to the bottom of the carb. I haven't seen one of those since I was a kid.

[El Camexican]

Oh man I just had a flash back when I saw that picture. My 1970 Nordic 399 had a Tillotson diaphragm carburetor with a filter like that which screwed right to the bottom of the carb. I haven't seen one of those since I was a kid.

That's the carb! First one I ever rebuilt outside in the cold, I was probably 9 or 10 and wanted to ride something fierce. Might be why my neck and back hurt now too, from sticking my head upside down into the cowl of that sled.




One thing I forgot to mention earlier is that these filters stop so much fine crud that they tend to plug up often. Carry a screw driver with you and don't try to set a land speed record unless you're sure it's been recently cleaned.

[fabiodriven]

Haha, that's funny Nico. Aside from messing around with a couple lawnmower carbs, the Tillotson was my first carburetor to rebuild as well. I remember looking at the directions with the stack of different diaphragms and gaskets and thinking "Oh my lord what did I get myself into?" So not much has changed in the 25 years I guess. Ha! Little did I know at that time that there are hardly any other carburetors out there like the Tillotson, but I still learned from it.

[El Camexican]

Haha, that's funny Nico. Aside from messing around with a couple lawnmower carbs, the Tillotson was my first carburetor to rebuild as well. I remember looking at the directions with the stack of different diaphragms and gaskets and thinking "Oh my lord what did I get myself into?" So not much has changed in the 25 years I guess. Ha! Little did I know at that time that there are hardly any other carburetors out there like the Tillotson, but I still learned from it.

Remember the rebuild bags? Always came with too many parts, so you had to make sure you laid everything out in order and put only what was needed in. I remember my Dad telling me that they used that carb, or at least that style of carb on airplanes because they worked upside-down. If you recall flipping your sled over it probably didn't stall, did it?

The fuel pump on a Tri-Z is basically a sideways section of the bottom of a Tillotson carb, but less reliable.

Now you've got me going down memory lane in 3rd gear. Didn't those carbs have an adjustable main jet? I remember setting the idle with a screw on the second butterfly (first was the choke) and that there was a spring loaded screw with a Tee on it that you could tune as you rode. I didn't even know what jetting meant back them, but I recall turning the screw to make it run better. I can't recall for sure if there was more than one adjustment screw on the carb, but there might have been a small air screw as well.

[Rob Canadian]

Since getting down here I’ve noticed that fuel filters plug up faster than they did up North, but the dirt bikes and trikes in particular seem to get a lot of nasty material in the float bowls even with inline filters.

What areas are you comparing the gas when you say 'north' and 'down here'?

To be honest I do not have filters on my trike or my dirtybike. I am a bit spoiled with the gas here in Canada. Working in the automotive field we only have 1 vehicle that has a interval to replace the fuel filter. Years ago I worked for a Bosch Center. The VW's needed to have the fuel filter replaced regularly.

With that said the vehicles I work on do not have a fuel filter. They do but not a regular thing to change.

That filter is doing is doing a great job!!! I remember seeing those years ago.

[stoshu]

Always extra parts. Here’s the filter that screws onto the pump

[El Camexican]

What areas are you comparing the gas when you say 'north' and 'down here'?

To be honest I do not have filters on my trike or my dirtybike. I am a bit spoiled with the gas here in Canada. Working in the automotive field we only have 1 vehicle that has a interval to replace the fuel filter. Years ago I worked for a Bosch Center. The VW's needed to have the fuel filter replaced regularly.

With that said the vehicles I work on do not have a fuel filter. They do but not a regular thing to change.

That filter is doing is doing a great job!!! I remember seeing those years ago.

Mexico VS Canada. I've had my truck filter plug up here and there is always way more sediment in the bike bowls than I ever saw in Canada. The Premium fuel we get here is refined in the USA (no alcohol ), but between the tanker trucks and underground tanks a lot of junk gets into it. Because it's monitored by weight I wouldn't be surprised if some of it gets diluted on the way to the stations.

I have an orange plastic jug that you can see clearly into from the top and all it takes is 15 liters straight out of the Pemex nozzle to get a 1/8 teaspoon of gunk in it. Still, that's not the bad stuff. When we get out into the desert we take what we can get. We once filled up by siphoning out of an old abandoned S10 on blocks as the Sun was setting. I recall my engine rattling when I rolled on it even though it was mixed with at least 6 liters of pump fuel. I have no idea what came out of that truck, but we paid triple the regular price and thanked the rancher for it.

[El Camexican]

Always extra parts. Here’s the filter that screws onto the pump

I've seen those on eBay, but I also seem to remember that one half of the style I posted bolted to the bottom of the carb. I recall we had a few spare carbs around and some of those didn't have a place for the filter, so we ran a complete filter in line. It's been 40 years and a lot of beers, I could be wrong.

Fabs: Was yours like this one, or line the one I posted?

[99gsxr750]

Haha....I remember my chilhood buddy's Arctic Cat mini-bike having one of those fuel filters.

[fabiodriven]

Fabs: Was yours like this one, or line the one I posted?

The filter stoshu posted is the exact one I was talking about. I could see the resemblance in it as soon as I saw your in-line version though.

[Rob Canadian]

Mexico VS Canada. I've had my truck filter plug up here and there is always way more sediment in the bike bowls than I ever saw in Canada. The Premium fuel we get here is refined in the USA (no alcohol ), but between the tanker trucks and underground tanks a lot of junk gets into it. Because it's monitored by weight I wouldn't be surprised if some of it gets diluted on the way to the stations.

Not too get too off topic on this and more of a insight. I pumped gas back in 1985 for a year and a bit. All tanks are underground. I had to do water dips on the in ground tanks. Yes there is water on the bottom of the tank. The pump for the fuel sits about 3 feet above the bottom. ( I am just going off memory). I would NEVER go and get gas from a station that a tanker just dumped fuel. I did have a tanker 1 night that was 50/50 fuel/water. I got the call as the tanker arrived. Sure enough. YUP 50/50 mix... We in Canada have to replace in ground tanks. (not sure how often?). I can only say some of the tanks that you are getting fuel from are not great of condition.