You'll need something stronger than hose clamps if you're pushing 65psi for EFI
CK5
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You mean the 255? I suppose if the regulator can flow enough fuel to relieve the pressure, it could work, I did not think the factory TBI regulator could flow enough to drop the pressure down to the correct psi with that pump, but I have never tried it. When the pump flows too much for the regulator then you can't turn it down enough, they definitely make carb regulators that can drop the pressure enough, I've used those. But that pump has to have a bypass regulator, it can't be a dead head regulator.
That's not a TBI sending unit, you want a TBI sending unit to make it easier for the high pressure fitting adaptors. Otherwise you can cut them and double flare them. I prefer the TBI sending unit with the AN adaptors.
Also, that is the ~25 gallon blazer tank, it has the shorter bottom, not the tall bottom with the angled back of the 31 gallon tank.
If I recall correctly some of the suburban tanks are higher capacity, up to 40 gal for the deep one, because the can be longer with the longer tail.
Normally with my customers I just tell them to get the TBI tank and sending unit from Rock Auto, and then I supply the Walbro pump.
I can get the Holley tanks but I like the factory sending units better and the Holley tanks cost more and have more holes in the top of the tank than just 1 like factory.
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Hmm, I thought it was a TBI sending unit because it has 4 line outs, what else would need that? Some other fuel injection model? The plot thickens
Keep in mind the 2 fuel lines with the nuts at the end have been cut off.
Oh and yes Walbro 255
According to the dimensions you're right it does look like it's a 25 gallon tank, just need to find the correct sending unit for this size tank.
Keep in mind the 2 fuel lines with the nuts at the end have been cut off.
Oh and yes Walbro 255
According to the dimensions you're right it does look like it's a 25 gallon tank, just need to find the correct sending unit for this size tank.
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I was waiting to see if anyone was going to correct this.Hmm, I thought it was a TBI sending unit because it has 4 line outs, what else would need that? Some other fuel injection model? The plot thickens
Keep in mind the 2 fuel lines with the nuts at the end have been cut off.
Oh and yes Walbro 255
According to the dimensions you're right it does look like it's a 25 gallon tank, just need to find the correct sending unit for this size tank.
Yes the one you showed here is a 25 gallon.
The 31 is a bit taller and definitely tapered in the back.
The suburban and the k5 31 gallon tanks are identical in case anyone else needed that information.
The only different tank are on vans, because the van has wider space between frame rails
Hmm, I thought it was a TBI sending unit because it has 4 line outs, what else would need that? Some other fuel injection model? The plot thickens
Keep in mind the 2 fuel lines with the nuts at the end have been cut off.
Oh and yes Walbro 255
According to the dimensions you're right it does look like it's a 25 gallon tank, just need to find the correct sending unit for this size tank.
Rock auto has sending units for 25 gallon or 31 gallon, just look up an 87 blazer.
And you are correct on the sending unit, I didn't realize the metric nuts were cut off.
Does that tank have a baffle for the pickup?
Yeah, the tank has a baffle trey in it.
Proof you can run a Walbro 255 in a stock TBI engine with internal stock regulator. I realize its a 4.3 but similar throttle body and regulator.
Has anyone tried these adapter fittings on Amazon?
Has anyone tried these adapter fittings on Amazon?
I have ran those type of fittings with no issues but always bought the Earls version. I dont think they are much more money than that.
Earls are good, I use Fragola or Earls depending on what else I am buy with it, they are both good. Fragola has a better price and is a USA made product. I don't trust the overseas stuff with critical plumbing.
Thanks! Steve was asking if they still sell the factory braided lines from the tank these days but I didn't think those lines are still being reproduced. You can always get used braided hoses only but then you have 40 year old lines that could leak down the road. I realize you can do the -6AN conversion with those adapters (pic below) which is what most do or go to barb fitting to rubber line after the -6AN with another adapter.
Any ideas on this?
So, got the new sending unit, first thing I did was to check the resistance, all good there. I then thought I should hook the new sending unit up, outside the tank to test if the fuel gauge works properly. So hooked the new sending unit up and of course the gauge read way past full (both with float up and down) which would indicate a bad ground or wire etc. so before I headed down the path of looking at all the wiring I decided to hookup the old sending unit back up, sure enough it worked like it always did (empty at 1/4 tank and full at 1/4 tank past full). Then I though the only thing different is the old sending unit still had the pump plugged in so decided to plug the pump into the new sending unit and sure enough it now read exactly on empty, pretty excited, next moved the float all the way up and bam, still stayed on empty... crap!
So this is where I am now, I have the new sending unit with the old pump attached plugged into the factory wiring harness and the ground hooked to the frame, it always reads empty no matter where the float arm is, any ideas on what to check next?
So, got the new sending unit, first thing I did was to check the resistance, all good there. I then thought I should hook the new sending unit up, outside the tank to test if the fuel gauge works properly. So hooked the new sending unit up and of course the gauge read way past full (both with float up and down) which would indicate a bad ground or wire etc. so before I headed down the path of looking at all the wiring I decided to hookup the old sending unit back up, sure enough it worked like it always did (empty at 1/4 tank and full at 1/4 tank past full). Then I though the only thing different is the old sending unit still had the pump plugged in so decided to plug the pump into the new sending unit and sure enough it now read exactly on empty, pretty excited, next moved the float all the way up and bam, still stayed on empty... crap!
So this is where I am now, I have the new sending unit with the old pump attached plugged into the factory wiring harness and the ground hooked to the frame, it always reads empty no matter where the float arm is, any ideas on what to check next?
How’s the connection at the bulkhead fitting of the pump hanger? Where the wires pass through.
When you checked resistance on the new sender did you sweep the arm and see the value go from 0-90ohms?
I’d say it’s a ground issue but you said it worked when you plugged the old one in.
Might be worth it to recheck the connector on the sender and make sure they pinned it to the same positions. That would be about the only way they both work checking resistance but only one works plugged into the truck.
I’d say it’s a ground issue but you said it worked when you plugged the old one in.
Might be worth it to recheck the connector on the sender and make sure they pinned it to the same positions. That would be about the only way they both work checking resistance but only one works plugged into the truck.
I unplugged the sending unit and turned the ignition key to the "ON" position, it pegged past the full position indicating the wiring and fuel gauge itself are good.
Then I connected a jumper wire from the sending unit to the battery, nothing still reads empty.
The resistance was 07.3 - 97.7 shouldn't it be 0-90?
Then I connected a jumper wire from the sending unit to the battery, nothing still reads empty.
The resistance was 07.3 - 97.7 shouldn't it be 0-90?
