In line fuel filters

[brian GT6.]

I'm just replacing all the fuel hoses on the gt6 with ethanol resistant hoses. From the end of the solid pipe as it enters the engine bay to the fuel pump I want to put in an inline filter before the fuel pump. I'm not sure whether to use on of the glass ones, or one of the cheap plastic ones. As I see it the glass ones have rubber o ring seals so those would have to be ethanol resistant whilst the plastic one have paper elements.

 

Any thoughts?

[Colin Lindsay]

I have three glass ones bought over the years and never used... I'm always keeping them for that 'special' car that never gets finished. They look nice but a bit blingy for just a fuel filter; but then you can clean them out provided the O rings are suitable to be reused or you can obtain suitably sized spares. They do appear to have a fine mesh filter which may not be as good as a paper element in keeping particles out of the carbs.

I use plastic versions on the GT6 and change them at least yearly; there are two or three versions some with plastic frames round the element and some with metal. At under a pound each at shows I'd reckon they're a better option if treated as a disposable item and changed as they discolour or perish.

[dougbgt6]

Brian,

I have glass in the same place, It’s been there 5 years or so. I had it apart last year to clean the filter and no sign of O ring deterioration, so didn’t change them.

I guess somebody somewhere will be making ethanol proof O rings. 

I'm all for bling! Glass & chrome still looks good after 5 years, I guess another 5 and Colin will have spent more on fuel filters than me. 

Doug

[daverclasper]

Make sure the internal bore is large enough for full flow and the external diameter suitable for the hose to fit. Maybe obvious, though not to me when I bought my first one!. 

[Nigel Clark]

I've got a glass filter on my GT6, though it doesn't seem to collect much debris. As has been said, the mesh of these glass filters is not as fine as the disposable plastic type with paper filter inside. I've never found SU or Stromberg carbs to be terribly sensitive to fine sediment. The glass filters can remove small rust flakes etc coming through from the tank and in my experience, that's good enough. Usually any really fine sediment collects in the bottoms of the float chambers and has no discernible effect on how the engine runs.

The Weber 38DGAS fitted to my Scimitar is a different story. Any fine sediment sediment getting into the carb soon blocks the idle passages, causing lumpy tickover and hesitant progression. It's necessary to strip the carb and blow through the idle circuits with compressed air to clear the muck. I've fitted two plastic/paper element filters to the Scimitar and that keeps it running well. I change them every year.

Based on this experience, I surmise that SU and Stromberg carbs don't need fine filtration, as there are no fine fuel passages in their design. Webers and presumably Solexes as fitted to some Heralds and early Vitesse 6s benefit from fine filtration of the fuel.

Nigel

[Qu1ckn1ck]

I believe that the club shop supplies the glass filter as recommended for use with ethanol, I bought one together with their rubber fuel pipe and hose clip replacement kit.

[Nigel Clark]

1 hour ago, Qu1ckn1ck said:

I believe that the club shop supplies the glass filter as recommended for use with ethanol, I bought one together with their rubber fuel pipe and hose clip replacement kit.

I have an earlier version of that glass filter. Bought it from the Club Shop and fitted to my GT6 many years ago.

Still works fine, and so far it's unaffected by unleaded/ethanol. I'm going to watch it carefully when we switch from E5 to E10. 

Nigel

[Peter Truman]

interesting discussion, here in Vic, Aus we can (I think) get non ethanol petrol (BP, 98), but other brands generally have 5% as standard and 10% is available ( new cars). IN NSW and some other states ALL petrol is a min of 5% ethanol, and 10% available.

Now re filters I use the plastic type but the Bottom centre inlet and Top side outlet as it fits tidier, virtually straight hose in and a short straight hose 2in long straight to the pump inlet. I replace them every few years as there inexpensive, never had one block or with a lot of debris.

I've never heard of ethanol attacking the plastic body of the filter, surely in these days there made ethanol resistant plastic! I think I would be more worried with the bling filter O rings.

An amusing story from my old Triumph club was that most of us in days of yore when lead was removed from petrol used to a blend of petrol and avgas, which was quite expensive, a close American friend (Mech Engineer) with a 2.5PI was too tight to follow suit (never carried more than a couple of bucks in his wallet), one day we talked him into it and several of us went down to the local airport to see him fill up with avgas, car ran great home, BUT next morning  he got up to a big puddle of petrol/avgas under the engine, he virtually cried at the $60 of avgas on the floor, it appears the avgas ate through the rubber/nitrile O rings in the PI metering unit, which at some significant expense he had just reconditioned. He's never let us forget what happened, but we still laugh at it!

The avgas not only provided the lead but ensured the high octane rating that our Trumpies loved.

Peter T

[Colin Lindsay]

12 hours ago, Peter Truman said:

The avgas not only provided the lead but ensured the high octane rating that our Trumpies loved.

Peter T

Sadly, with the close of many Military bases over here a few years back we lost the availability of Helicopter fuel, which was much loved by motorbikers and other motoring enthusiasts with a source to obtain it...

[Peter Truman]

CAn’t legally get avgas here anymore not allowed to sell off site anymore ie to the general public. If the EPA stopped you and tested your fuel it would cost you serious $ in fines. In reality they would never individually stop a car and test the fuel there’ve got bigger fish to fry.

The EPA rely on dobbers for such as noisy exhausts and smaller car type enviro infringements Smokey exhausts.

Peter T