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What does a fuel pulsator dampner do? is it safe to eliminate it with a bypass hose?

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Old 10-20-2012, 10:30 AM
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Default What does a fuel pulsator dampner do? is it safe to eliminate it with a bypass hose?

Does anyone know what a fuel pulsator dampner does? it sits right above the fuel pump and is plastic. im doing a fuel pump on my 95 S10 4.3 C.P.I. and do not know if i should re-use it. i want to do whats best for the long run. i found a GM tech bulletin that says it can reputre or crack from the ethanol in the gas causing hard starting or no starting and to replace it. included with my new EP381 AC Delco pump kit is a rubber bypass hose that can be used. the instructions say to use what you find there already, either the hose or the pulsator. but do not know the pros and cons. i searched the forums here but found nothing on this pulsator. anyone know what it does? and what happenes if you remove it?
 
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Old 10-20-2012, 12:42 PM
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Originally Posted by bigdaddykane93
Does anyone know what a fuel pulsator dampner does? it sits right above the fuel pump and is plastic. im doing a fuel pump on my 95 S10 4.3 C.P.I. and do not know if i should re-use it. i want to do whats best for the long run. i found a GM tech bulletin that says it can reputre or crack from the ethanol in the gas causing hard starting or no starting and to replace it. included with my new EP381 AC Delco pump kit is a rubber bypass hose that can be used. the instructions say to use what you find there already, either the hose or the pulsator. but do not know the pros and cons. i searched the forums here but found nothing on this pulsator. anyone know what it does? and what happenes if you remove it?
The Dampener is there to dampen the fuel pulsations coming from the fuel pump to the rest of the system. I have read several reports where it will cause a loss of fuel pressure resulting in stalling. One fellow replaced his with a length of fuel line (rated to 80 psi) and it solved his problems with stalling.

I recently replaced the fuel pump on my 95 blazer and It didn't have a fuel pulse dampener in the vehicle. It was just a piece of fuel line where it should have been. I have had my blazer close to two years and have no problems with the fuel system other than a failed fuel pump.
 
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Old 10-20-2012, 03:41 PM
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Originally Posted by Ramjam2112
The Dampener is there to dampen the fuel pulsations coming from the fuel pump to the rest of the system. I have read several reports where it will cause a loss of fuel pressure resulting in stalling. One fellow replaced his with a length of fuel line (rated to 80 psi) and it solved his problems with stalling.

I recently replaced the fuel pump on my 95 blazer and It didn't have a fuel pulse dampener in the vehicle. It was just a piece of fuel line where it should have been. I have had my blazer close to two years and have no problems with the fuel system other than a failed fuel pump.
my new delco pump came with the bypass fuel line in the kit. id rather use the fuel line if im 100 percent sure its ok too. just curious, is your blazer a 4.3 C.P.I ? and does it idle smooth without the pulsator?
 
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Old 10-21-2012, 10:20 AM
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Originally Posted by bigdaddykane93
my new delco pump came with the bypass fuel line in the kit. id rather use the fuel line if im 100 percent sure its ok too. just curious, is your blazer a 4.3 C.P.I ? and does it idle smooth without the pulsator?
Yes, Runs just fine and idles smooth. Just be sure not to run your tank dry or low for extended periods. The fuel pump is liquid cooled and running the tank dry will fry your fuel pump. Another fellow in the forums said his GF ran her blazer dry several times due to a non working sender unit and his fuel pump started acting up.

Double check the electrical connection inside the tank when installing your fuel pump. I forgot to connect it and I had to drop the tank a second time.

read this(last post)
1995 Chevrolet Truck Problem 95 Blazer Won't Start Read Other Comments On This
 
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Old 10-21-2012, 02:11 PM
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wow thats an informative link, thanks. just curious, whats your fuel pressure at now? and what brand fuel did you have and what brand did you buy? thanks again
 
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Old 10-21-2012, 05:08 PM
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Default Fuel pressure

It hovers at about 62 psi after turning ignition on but not cranking.

I got an AC delco I think. I have a 95 blazer 4 door with 4.6 mfi.

Want to get an idea of what you are in for?
.

If you haven't dropped a tank before, be careful of the 2 (one up front and one at the rear)rollover vent valves. You will break the nipples off if you aren't careful.

Another helpful tip is if you are doing this yourself is to support the fuel tank in the front with blocks to aid in mating the tank to the fill and vent lines when re-instaliing the tank.
 

Last edited by Ramjam2112; 10-21-2012 at 05:12 PM. Reason: left out an important detail
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Old 10-22-2012, 01:45 PM
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thanks. whats your fuel pressure at now while idling?
thanks again
 
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Old 10-22-2012, 02:44 PM
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Default Don't know.

Originally Posted by bigdaddykane93
thanks. whats your fuel pressure at now while idling?
thanks again
I never bothered to check. Maybe it's something I should do when I get the time.

My Blazer quit stalling and the fuel pressure holds for several minutes after turning the key on but no crank. I figured the problem solved and moved on to other things.
 
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Old 10-23-2012, 11:26 AM
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Originally Posted by Ramjam2112
I never bothered to check. Maybe it's something I should do when I get the time.

My Blazer quit stalling and the fuel pressure holds for several minutes after turning the key on but no crank. I figured the problem solved and moved on to other things.
ok thanks, if you do end up checking the fuel pressure while at idle, can you post it here?
 
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