LS1 fuel issues
Thread Starter
Teching In
Joined: Apr 2019
Posts: 9
Likes: 0
LS1 fuel issues I inherited a 1986 Chevrolet K5 Blazer recently. It had a new LS 350 put in in the late 90s. It probably has around 30000 miles on the motor. I am about to get going on it with my son for his first car. It hasn't been cranked in a few years, but the last time we drove it it cut out under moderate to excessive (if that's a thing) throttle. It did fine while easing around. I have been told recently that my problem is that my stock fuel pump cant give the fuel required for the LS1. I was considering putting one of those inline electric low pressure edelbrock fuel pumps on it. Any thoughts or suggestions? I will be servicing the K/N air filter, changing oil, changing spark plugs and wires already. Thanks
TECH Senior Member
Joined: Jun 2016
Posts: 22,291
Likes: 3,616
From: Central Cal.
Exactly which engine do you have? LS1? If the pump in there was the correct pump, and it did well originally, replace it with another of the same type. As said above, a low pressure pump will not work. These engines use 58psi.
Last edited by G Atsma; Apr 18, 2019 at 10:33 AM.
Thread Starter
Teching In
Joined: Apr 2019
Posts: 9
Likes: 0
Fuel pump The engine prior to this one had a stock 305. We purchased it when the local dealership put the 350 in it. It didn’t run right because the dealership set the timing for a 305 as the spec sheet on the hood said🙄. My brother drove it through high school, then my dad drove it for a year or so. Been sitting up covered since then other than me moving it from his house to mine 4 years ago. I drove it occasionally for a month or so and that’s when I discovered the stall. It hasn’t been cranked since then. So, disregard the low pressure electric fuel pump. Just wanting some ideas of what’s going on. My idea is that it likely still has the fuel system from the 86 Blazer with the 305 and not feeding the ls1 engine as it should. As far as which engine, I’m not sure. The guy that had it before us owned a Chevy dealership and put a brand new ls1 in it around 1997ish.
Thread Starter
Teching In
Joined: Apr 2019
Posts: 9
Likes: 0
Thanks DB. I don't know the context or situation of his comment as it was in general conversation. He did not providea technical DIY instruction manual type answer.. He did not break it down, and I didn't ask anymore questions. He did imply that it was likely starving for fuel. Perhaps the folks that built the truck didn't put the correct part in there, and it sounds like you may be inferring that if it is a pump for a 305, it is likely inadequate?? I will check that out. Thanks for the comments
Trending Topics
Can you post pictures of this engine? 97 was the very first year LS1 and that was only in the corvette. I can't see a brand new corvette LS1 going into this truck and it not having the correct fuel system done, but then again there is some crazy **** done in this world. lol
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Thread Starter
Teching In
Joined: Apr 2019
Posts: 9
Likes: 0
Stall Yeah, my truck is in my barn. I’ve got the LS owners manual in the console😁That will answer all the questions for sure. I will check the parts. The manual gives requirements down to spark plugs and wires. Hopefully, I can get going on this thing this month. Will let you know what I come up with. I know for sure it has an aftermarket tank, so you’re likely right, but they did have the timing set wrong. At the Chevrolet dealership!🙄this guy owned the Chevy dealership. Looked like a show truck when my brother got it. Mouse cage now!! Going to try to bring it back to glory! Thank ya’ll for your comments and suggestions
1997 was first year of Gen 3. Gen 2 (LT1 1992-1997) is the Gen 1 SBC with reverse flow cooling, optispark dist ( moved from firewall). Same exact dimensions as Gen 1 SBC.
i guess we need to wait until you post a pic. If you say it’s a LS1...you know more than us. Post it up...than we may be able to help you with fuel issues. No hard feelings!
i guess we need to wait until you post a pic. If you say it’s a LS1...you know more than us. Post it up...than we may be able to help you with fuel issues. No hard feelings!
Thread Starter
Teching In
Joined: Apr 2019
Posts: 9
Likes: 0
Issues No problem. Was asking about a stall and things that I might need to investigate when I start fixing it up. I have learned that I just need the right part, my friends dont know what they are talking about, I don’t know what I’m talking about, a brief history of the GM 350, folks like to educate folks on what they have or don’t have, that I should feel dumb if I can’t look at an engine and tell what it is (which I can), and there is no simple answer to my question given the vague description I have. I also researched some of the terminology used in this thread and have a fair understanding of what LS LT gen 1-5 etc. are. No hard feelings. Take care ya’ll!! . thanks!!
