Went out to start my car yesterday,and engine cranked,but no start! After a few simple checks,it turned out no fuel was being pumped. I removed the short fuel hose to the carb filter and no fuel with the engine cranking. I have replaced the fuel hose at the tank,the short one that is at the front of the door,and the one that is from the line to the fuel pump. OK,I got out my vacuum tester and started to pull vacuum on the hose I disconnected at the carb. Not really any reading on the gauge,but fuel appeared,I'm using clear hose on the hand vacuum pump. I stopped before the fuel entered my hand pump. Now,when I cranked the engine,fuel delivery was fine! WTF! I have checked the hoses and lines for leaks and can find none. Now I'm going to get to the primary reason for this post! I'm considering installing an electric fuel pump. I want to mount it back where the hose exits the fuel tank. I would like to leave my existing engine driven pump as it is and just let the new one pump through it. Do ya'll think this is a good idea? Would you just replace the mechanical pump? I don't know if it's even bad,as it pumps fuel at the right volume and pressure,if you prime it first. The 2 units are similar in price. What do you think of electric pumps? I know you guys have experience with this stuff! My car has a totally stock 250 with a Carter RBS carb. Thanks for any ideas on this!!!
It woudn't hurt anything to do it that way but a cheap electric pump dont usually last to long! i would say your mechanical pump (even though press and volume may be ok) is not holding its prime, i would replace with new mechanical they have been tried and true since they quit using gravity feed sys.
Your asking for tons of problems running both pumps, super high pressure, when the mech. pump fails gas will be pumped into crankcase. Stick with mech pump if pump is your problem. Do some more troubleshooting first.
Use one or the other, but not both. I put a new mechanical pump on my car back in 2005. It was just a cheapie pump from Advance Auto, and it currently has about 140,000 miles on it and still working fine, so I reckon the mechanical pumps are pretty reliable. Seems like the only thing that kills them is age.
. dont run the electrical pump thru the mechanical. just run direct from electrical to carb . but be sure what pressure rating it is. you may have to buy a regulator. hope this helps
I had 2 Advance Auto fuel pumps that didn't last 3 weeks each. Went to trade the 2nd one for a 3rd time and I found out the 30 day guarantee expired because the warranty started on the first pump I bought. After enough blasphemy on my part about their cheap China parts they gave me a 3rd one to get me out of the store. So far this one has lasted over 2 years. As a general rule I don't buy anything made out of metal from a cheap discount autoparts store unless I have too
Fuel pump I wud run one or the other. With a stock engine I wud most likely get a quality mech pump, Carter, Holley or Edlebrock and forget abt all the wiring and mods to go electric.
i purchased a cheap electric pump from autozone years ago and ran it on my impala for 6 years with no issues. it'll end up in my countless spare parts area... sence i am going efi.
I was thinking the same thing... Diaphram ruptures, and you can fill the engine with gasoline. If you have trouble with a mechanical fuel pump, you should check the oil for signs/smells of gasoline. Your mechanical pump can put gas in the crankcase by itself, without help from the electric pump. Adding another pump running through the mechanical pump just makes a rare problem much more likely. Fwiw, I would just troubleshoot, and if it is the mechanical pump getting worn out... replace it. Good luck
Thanks,you guys! After doing some more research,I'm just going to get a new mechanical pump! I feel that since mine is now 18 years old,it sure wont hurt to replace it! I looked at electric ones,but by the time I'd get wire and fittings to hook it all up,it would cost way more than the original! I've heard mostly good about the original pumps,and a lot of not so good on the electrical ones! Easy choice!
1.) 18 yrs. I'd say u got ur monies worth. Nobrainer - CHANGE IT. 2.) Wired up and fitting - somewhat of a hassle for stock engine. 3.) Cost more than orginal - I think so.
Not all elec. pumps are High Pressure! some are low pressure and cut off when they reach the limit they are set at. there for it would not pump gas into the crankcase.
Yes, I know of the5-8 lb fuel pump,,, but now your mech. pump is being fed 6lb pressure insted of sucking the gas. End result is way too much pressure. If the diaphram in the mech. pump ruptures, the electric pump is going to pump bunches of gas into the crankcase. Hope that clears this up for you.
when i got my pump from oreilley, the guy told me about a "sleeve" that you can get, has a metal tip that fits the arm of the pump, and a nylon, oor something..... type of material that basically forms a glove to the pump, bolts on sandwiched between the pmp and block, and provides a secondary barrier to the crank case, in the event that the diaphragm fails... still never seen one myself, but may be something worth looking into? A little added protection never hurts
