All: My Dino was running fine until I recently filled up the tank and added some octane booster (yes, I have higher compression pistons and California premium gas is only 91 octane). Within 5 minutes of driving a fuel issue became evident. When I stopped the car, the fuel pump was quickly ticking and didn't slow (liked it always does) when I pumped the gas. I believe I dislodged some sludge which has clogged some part of the system prior to the fuel pump. Does anyone know if there is a screen on the tank (this has clogged on a few of my other vintage cars)? Is there a fuel filter between the tank and the fuel pump? Can anyone show me the location of this (pics would help)? Thanks. jts
Yes there are three filtrant sections to the standard Dino E fuel system that I have - a screen inside the LH tank on the inlet side of the outflow nipple, - then fuel goes to the filter, pump and - then there are inlet screens on the carbs. Even though it is the last pass in the filtration system I would check the inlet screens on the carbs first. An even simpler test is to remove the fuel line into the carbs and visually inspect for pressure, you need 7psi flow and all upstream is flowing fine. Image Unavailable, Please Login
Check for water in the fuel. Water will generally allow the engine to sputter, but not run well. When your checking the fuel flow as Syncro suggested, capture some gas in a glass or bottle and let it settle. If water is a problem, you'll see it at the bottom. That doesn't explain the pumps continuing to run - although some pumps continue to run when the pressure is right, just at a reduced rate. A friend had his 50s Gull Wing pick up water in his fuel during a gas stop during a vintage rally - it took him most of an hour to purge the bad fuel before he could continue on his way... Ken
Clogged idle jets will make it not want to idle and run rough. Easily unscrewed and blow out the idle jets (one per throat, 6 total with compressed air and using a thin wire to clean each jet)
Thanks. Can you show a picture of the fuel filter in the car? Also, can the fuel tank screen be cleaned without dropping and/or emptying the tanks?
Thanks. I do not think it is water. It sounds like there are three potential screens/filters where sludge can clog. I am going to check these.
If you suspect water then add +-1 ltr of alcohol to the fuel tank and go for a good ride. This should fix the problem. This is standard carburetor issue fault finding procedure in the (cold) part of the world I live in...-
1) Absolutely, it is just in front of the Driver's side rear wheel. I have photos, see below. 2) Probably. The fuel tank screen is part of the nipple as a nylon "bag" filtering from inside the tank. The assembly overhangs the rear diagonal frame oval in my car (photo att), and is removed by unscrewing the nipple hexnut fitting with a spanner. So yes I can, but then again each Dino seems to be different...YMMV BTW, my tank screen had failed as it was starting to split. Removing it showed that Ferrari had used a nylon type screen and aing showed it to be really brittle. There was evidence (red RTV) of handling by previous which I think can actually damage those old tank screens. I replaced mine with new Here is TAV 7 and my photo of the parts A) Item 11 is the tank filter, mine over hangs and can be removed with a large spanner and small movements. Dino parts sell it in two parts http://www.dinoparts.eu/EN/ferrari-246-gt-gts/carburettors-fuel-supply/tank-more/2/ B) Item 54 is the filter assembly. It is a canister filter, replacements sold by UFI include filter element and a new sealing gasket. The round, grey case is not a spin-on type but attaches via top bolt and loosening it allows it to drop down. Again, an easy way to check all of this in under 10 mins is to remove the fuel line to the carbs and watch the flow. I recall the flow as 7psi but TonyL is probably more accurate on his readings so I'll defer to him for actual psi but your eye can tell if there is blockage quite quickly. If good flow, then you'll be chasing down the carbs, screens or even a bad float perhaps? Scott View attachment 2684776 Image Unavailable, Please Login
