Having trouble getting/keeping fuel flow to the carb. Installed rebuilt carb but could keep vehicle running for only a few miles. Wondering if there is an inline fuel filter somewhere (maybe on the frame) between the fuel tank and the carburetor. Changed the filter element inside the carb fuel inlet but no improvement. Thinking there could be another filter inline somewhere that is clogged. Thanks!
CK5
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Fuel filter question - 1979 Blazer K5 350 cc 4WD
- Thread starter BARSTOW_JACK
- Start date
I have a 77 GMC Jimmy 4wd and the only stock fuel filter I have is on the carb itself. Kind of a pain to replace itself so I added an inline filter between the fuel pump and the carb.
MEMO43
1/2 ton status
How old is your pump, also what carb and who rebuilt it?
seems either there is a blockage in the carb or the pump can't keep up, blown diaphragm.
Easy way to check is to smell your oil, if it has a gas odor
chances are you are pumping gas into the oil.
as mentioned install an inline filter. I like tbe plastic with filter, yoj can actually see your fuel level
Avoid the shiny glass ones, don't run the chance of beaking the filter an sparyjng gas every where
seems either there is a blockage in the carb or the pump can't keep up, blown diaphragm.
Easy way to check is to smell your oil, if it has a gas odor
chances are you are pumping gas into the oil.
as mentioned install an inline filter. I like tbe plastic with filter, yoj can actually see your fuel level
Avoid the shiny glass ones, don't run the chance of beaking the filter an sparyjng gas every where
if you have a split in the hose/s between tank and pump, the pump can get enough fuel to start and idle but not run don the road. Check ll the delivery hoses for cracks or gummy-ness. Factory the only filter is in the carb inlet. I have an inline filter at tank before pump. I added that.
There is a sock filter in the tank, but it's pretty coarse. I'm sure it could plug up, but that would be a lot of crud to make that happen.
Have you disconnected a fuel line far forward to see if you can siphon fuel out, and if the flow is decent?
Have you disconnected a fuel line far forward to see if you can siphon fuel out, and if the flow is decent?
Assuming you have a an original Rochester carb, there is an issue that manifests for some people as the internal filter region of the carb is small and sometimes the engine fuel starves with high performance capability. Some people delete the internal fuel filter and install an inline filter for additional fuel through-put. I personally have never had an issue with my low performance small block 400, (8.5 to one compression). Could a former owner have installed an unknown finline filter that now is clogged?
Only time I had a problem with my 400 was when it was 110 outside and I was pushing it really hard on the freeway and it vapor locked when I finally stopped. Solved that problem though by insulating the fuel lines near heat sources and the fuel line from the pump to the carb. Thanks Wes Harden for that one.
Could do a volume test on the fuel pump. Disconnect the coil wire, disconnect fuel line and put it into an empty soda or water bottle. Crank the engine for 30 seconds and you should get 6 oz of fuel, give or take.
