Hi all, A query to anyone with a retro fitted carb on a 2.5l 4 cyl. I know there are lots of posts on this and references to vapour lock but I thought I'd put some pics up to see if there is anything I can do to improve my filter, fuel line, pump, pressure valve set up??
Same issue as reported by plenty other folks really: drives fine for 30 miles at 60mph etc. But as soon as we hit traffic or slow down to a stop or crawl, the Jeep barely holds its revs and seems to want to stall, almost like it's running out of fuel (full tank so it's not a lack of fuel)
So here is my physical layout.
It seems to me there is a convoluted fuel line set up out of the tank and to the filter with a few ups and downs around the shocks and frame then down to the filter when a shorter more straight forward connection could be a better move? Is this advisable?
Should I move the filter closer to the pump?
Should I fit another filter in after the pump before the FPR or just before the carb?
Can I use one of those small see-through orange and plastic filters that let me see if it's getting dirty?
Any help would be really appreciated. Thanks all.
BTW, on the old Air Filter Housing box there was a pipe connected to the bottom of the box which led to a hole at the bottom of the engine block that apparently directed warming air from the block to the air filter to help with cold starts. The air box has long gone due to the carb conversion but the hole remains open on the engine block - should this hole be blocked off or a pipe fitted to it to divert the hot air coming out? I wonder if this is heating up the fuel lines or the pump, as it's right in the same area where the set-up below is........
Same issue as reported by plenty other folks really: drives fine for 30 miles at 60mph etc. But as soon as we hit traffic or slow down to a stop or crawl, the Jeep barely holds its revs and seems to want to stall, almost like it's running out of fuel (full tank so it's not a lack of fuel)
So here is my physical layout.
- Electric Fuel Pump/ Filter in tank has been removed.
- Fuel Filter (one year old) is the large canister type bolted to the rear D/S frame per original spec.
- Electric Fuel Pump is bolted to the D/S frame almost directly under the carb housing.
- Fuel line goes straight uphill from there to a Fuel Pressure regulator set at 3.5 psi.
- Then fuel line goes from there on a short curve into the Carb intake. It's wrapped in heat reflecting material.
It seems to me there is a convoluted fuel line set up out of the tank and to the filter with a few ups and downs around the shocks and frame then down to the filter when a shorter more straight forward connection could be a better move? Is this advisable?
Should I move the filter closer to the pump?
Should I fit another filter in after the pump before the FPR or just before the carb?
Can I use one of those small see-through orange and plastic filters that let me see if it's getting dirty?
Any help would be really appreciated. Thanks all.
BTW, on the old Air Filter Housing box there was a pipe connected to the bottom of the box which led to a hole at the bottom of the engine block that apparently directed warming air from the block to the air filter to help with cold starts. The air box has long gone due to the carb conversion but the hole remains open on the engine block - should this hole be blocked off or a pipe fitted to it to divert the hot air coming out? I wonder if this is heating up the fuel lines or the pump, as it's right in the same area where the set-up below is........
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