Olds 350 diesel to sbc swap

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Ryanbrown36

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Hi guys, I’m looking for some help on my olds 350 diesel to sbc swap, I have completed the swap and will be starting the truck up soon but have some questions about the tank situation. I have a dual tank setup and replaced the driver side tank with a new one to make sure there was no diesel left but my old passenger side tank is still on the truck and would like to know if I should plug that off somehow and where it’s best to do so(my fuel lines are All fresh from the new tank to the motor) for reference I’m 17 and have been doing this by myself so might be a dumb question but don't really know what I’m doing and want any old diesel getting in my fuel system. Thanks in advance
 
Ryanbrown36

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squaredeal91 said:
Wait... you have a 350 diesel??
That's cool
Click to expand...
Yes was originally a olds 350 diesel but the injector pump went and for what I was quoted for a rebuild it wasn’t worth it to keep it, the motor had 144k on it and never had a head gasket, ran like a top until the injector pump started to bugger up
 
Ryanbrown36

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squaredeal91 said:
If you're only going to run 1 tank hook everything to the one tank eliminating the selector valve and possible problems.
Click to expand...
thanks for the help, so am I just disconnecting the two lines running the the passenger tank or plugging them? And it’s these back line in the photo right?
 

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Blue Ox

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If you're set on running one tank follow the advice above.

However, with a gas engine you may find yourself missing that extra fuel. You can just drain the tank and blow out the lines. As long as the fuel isn't contaminated it's nothing to worry about.
 
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A little diesel in your gas won't hurt a thing,some guys intentionally add it as top end lubricant. I think it's BS but it doesn't hurt their stuff. And personally I'd rather use the passenger side tank. My weight on one side, fuel weight on the other,hopefully keep the springs from sagging uneven.
 
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Ryanbrown36

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Blue Ox said:
If you're set on running one tank follow the advice above.

However, with a gas engine you may find yourself missing that extra fuel. You can just drain the tank and blow out the lines. As long as the fuel isn't contaminated it's nothing to worry about.
Click to expand...
I’m not totally set on running one tank forever but I think for now to get it on the road as it will be my daily driver I just want one. There’s still some diesel in the other tank so just don’t want any problems for the start up and for the month I might get to drive it, thanks
 
Ryanbrown36

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Ricko1966 said:
A little diesel in your gas won't hurt a thing,some guys intentionally add it as top end lubricant. I think it's BS but it doesn't hurt their stuff. And personally I'd rather use the passenger side tank. My weight on one side, fuel weight on the other,hopefully jeep the springs from sagging uneven.
Click to expand...
Do you think If I were to drain passenger tank to the best of my ability and fill it up with gas it would be fine to run the two tanks? I have blown out all the lines from the driver side tank to the fuel pump as they were already new
 
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Ryanbrown36 said:
Do you think If I were to drain passenger tank to the best of my ability and fill it up with gas it would be fine to run the two tanks? I have blown out all the lines from the driver side tank to the fuel pump as they were already new
Click to expand...

Yeah, just dump the diesel and fill with gas. It will be fine. Or even suck the diesel out and fill with gas.


I'm intrigued by that selector valve. That 6 port valve looks nothing like the 6 port valve on my gas trucks.
 
Ryanbrown36

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bucket said:
Yeah, just dump the diesel and fill with gas. It will be fine. Or even suck the diesel out and fill with gas.


I'm intrigued by that selector valve. That 6 port valve looks nothing like the 6 port valve on my gas trucks.
Click to expand...
Ok thanks for the help, it is a 6 port and I was also confused as the photos I looked up did not look like mine, might be a Oldsmobile thing
 
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77Dmax

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An olds 455 would have been a bolt in swap! Cap the lines until you're ready to drain and hook them up..
 
Ryanbrown36

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77Dmax said:
An olds 455 would have been a bolt in swap! Cap the lines until you're ready to drain and hook them up..
Click to expand...
I would’ve loved to drop a 455 in there but I couldn’t find one and it is my daily driver so needed something quick and found a deal on a sweet sbc that I couldn’t turn down, are you saying cap the two ports going to the passenger tank on the selector valve for now?
 
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Ryanbrown36 said:
I would’ve loved to drop a 455 in there but I couldn’t find one and it is my daily driver so needed something quick and found a deal on a sweet sbc that I couldn’t turn down, are you saying cap the two ports going to the passenger tank on the selector valve for now?
Click to expand...
Just hook everything up as normal,leave your selector valve set to drivers side tank. When to run the passenger side tank syphon the diesel ad a couple of gallons of gas drive it a couple of days syphon it again. Fill it,done.
 
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Strick

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Welcome to the club fella. I just passed up a Canadian GMC that was a 5.7 diesel. Good luck in your swap & daily driver.

HS
 
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