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Scfi Fuel Pump Question

dwfatboy

By dwfatboy
in Ask A GM Technician

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dwfatboy New Member

dwfatboy

Posted
Posted

I have a 72 K5 Blazer with the powertrain out of a 98 Suburban with the 5.7. I pulled the fuel tank and the guy who I got the Blazer from did a butcher job on the tank to get the fuel pump and sending unit in the tank. I want to replace the tank and use an inline pump. Most of the pumps I find are running at 80-85 psi. The service book I have says the enging specs at 60-66psi. Would the 80-85 psi be too much for the pressure regulator and return? I am planning on running a stock tank and sending unit with the inline high pressure pump. The tank and pump that are in it now work but I think he must have used 2 tubes of caulk to get it to seal. It just don't feel safe running it the way it is. Any info or suggestions are greatly appreciated. Thanks

Zembonez Senior Enthusiast

Zembonez

Posted
Posted
I have a 72 K5 Blazer with the powertrain out of a 98 Suburban with the 5.7. I pulled the fuel tank and the guy who I got the Blazer from did a butcher job on the tank to get the fuel pump and sending unit in the tank. I want to replace the tank and use an inline pump. Most of the pumps I find are running at 80-85 psi. The service book I have says the enging specs at 60-66psi. Would the 80-85 psi be too much for the pressure regulator and return? I am planning on running a stock tank and sending unit with the inline high pressure pump. The tank and pump that are in it now work but I think he must have used 2 tubes of caulk to get it to seal. It just don't feel safe running it the way it is. Any info or suggestions are greatly appreciated. Thanks

HOLY 952 POSTS, BATMAN!

 

WTF?

txab Senior Enthusiast

txab

Posted
Posted
I have a 72 K5 Blazer with the powertrain out of a 98 Suburban with the 5.7. I pulled the fuel tank and the guy who I got the Blazer from did a butcher job on the tank to get the fuel pump and sending unit in the tank. I want to replace the tank and use an inline pump. Most of the pumps I find are running at 80-85 psi. The service book I have says the enging specs at 60-66psi. Would the 80-85 psi be too much for the pressure regulator and return? I am planning on running a stock tank and sending unit with the inline high pressure pump. The tank and pump that are in it now work but I think he must have used 2 tubes of caulk to get it to seal. It just don't feel safe running it the way it is. Any info or suggestions are greatly appreciated. Thanks

HOLY 952 POSTS, BATMAN!

 

WTF?

 

 

 

He's trying to catch up with you, Jim. :D

 

Site must have been really messed when he posted......

Zembonez Senior Enthusiast

Zembonez

Posted
Posted
I have a 72 K5 Blazer with the powertrain out of a 98 Suburban with the 5.7. I pulled the fuel tank and the guy who I got the Blazer from did a butcher job on the tank to get the fuel pump and sending unit in the tank. I want to replace the tank and use an inline pump. Most of the pumps I find are running at 80-85 psi. The service book I have says the enging specs at 60-66psi. Would the 80-85 psi be too much for the pressure regulator and return? I am planning on running a stock tank and sending unit with the inline high pressure pump. The tank and pump that are in it now work but I think he must have used 2 tubes of caulk to get it to seal. It just don't feel safe running it the way it is. Any info or suggestions are greatly appreciated. Thanks

HOLY 952 POSTS, BATMAN!

 

WTF?

 

 

 

He's trying to catch up with you, Jim. :D

 

Site must have been really messed when he posted......

 

I agree... even Brian would not do that. :D

 

NICE AVATAR! Welcome to the Clown Club!

2000DV4.8 Senior Enthusiast

2000DV4.8

Posted
Posted

When I was gone for 4 days, I had 18 pages of new threads to go through. I've been gone for less than 24 hours, and I see 13 new pages. I thought we were all just really talkative today. :D

grosss Enthusiast

grosss

Posted
Posted

I bow to you 72K5er, a member for less than a few hours and you've already got three wrenches! I've been a member for a year and only have two!! LOL... I do need to try a little harder I guess... Welcome! I hope the mods can fix you up soon, lol... I don't think a serious answer to your question will surface until then.

TexasAl Enthusiast

TexasAl

Posted
Posted
I have a 72 K5 Blazer with the powertrain out of a 98 Suburban with the 5.7. I pulled the fuel tank and the guy who I got the Blazer from did a butcher job on the tank to get the fuel pump and sending unit in the tank. I want to replace the tank and use an inline pump. Most of the pumps I find are running at 80-85 psi. The service book I have says the enging specs at 60-66psi. Would the 80-85 psi be too much for the pressure regulator and return? I am planning on running a stock tank and sending unit with the inline high pressure pump. The tank and pump that are in it now work but I think he must have used 2 tubes of caulk to get it to seal. It just don't feel safe running it the way it is. Any info or suggestions are greatly appreciated. Thanks

 

Hello,

 

The site has been having some problems, and your thread was posted a bunch of times. That's why most people are freaking out. As far as your question. Your regulator should handle it just fine, but I would be more concerned about your fuel lines. You may want to completely replace those with new fuel lines that can handle the 85 psi easily. Any general replacement fuel line will work just fine. If you go with a universal type fuel pump, you may be able to adjust the pressure as well. Good luck, and let us know what you end up doing.

 

-Al

dwfatboy New Member

dwfatboy

Posted
  • Author
Posted

Thanks for the reply. I don't know what happened. After I hit enter, it took a minute then my screen said "internal server error". I am sorry, I only wanted to post it once. I post in forums all the time and this has never happen before.

txab Senior Enthusiast

txab

Posted
Posted
I have a 72 K5 Blazer with the powertrain out of a 98 Suburban with the 5.7. I pulled the fuel tank and the guy who I got the Blazer from did a butcher job on the tank to get the fuel pump and sending unit in the tank. I want to replace the tank and use an inline pump. Most of the pumps I find are running at 80-85 psi. The service book I have says the enging specs at 60-66psi. Would the 80-85 psi be too much for the pressure regulator and return? I am planning on running a stock tank and sending unit with the inline high pressure pump. The tank and pump that are in it now work but I think he must have used 2 tubes of caulk to get it to seal. It just don't feel safe running it the way it is. Any info or suggestions are greatly appreciated. Thanks

HOLY 952 POSTS, BATMAN!

 

WTF?

 

 

 

He's trying to catch up with you, Jim. :)

 

Site must have been really messed when he posted......

 

I agree... even Brian would not do that. :D

 

NICE AVATAR! Welcome to the Clown Club!

 

I'm just trying to honor you. Oh Great Clown Master. :lol:

txab Senior Enthusiast

txab

Posted
Posted
Thanks for the reply. I don't know what happened. After I hit enter, it took a minute then my screen said "internal server error". I am sorry, I only wanted to post it once. I post in forums all the time and this has never happen before.

 

No worries. It happens here sometimes. More than we'd like.

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