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Replacing hard fuel line with rubber section/fuel filter housing size
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Replacing hard fuel line with rubber section/fuel filter housing size
It’s probably been a long time coming but I cracked the hard fuel line running from the carb to the pump. I know in an ideal world, I’d replace the whole line, but I need this thing on the road. Would it be wildly unsafe to get a new inlet/nut unit and splice the lines with a short length of fuel hose? I’ve cut out the bad section with a tubing cutter for now.
Additionally, since I absolutely can’t get the inlet off the filter housing and the nut is 100% rounded, I’m going to just replace the whole thing. Is there a part number or a measurement specific to the e4me fuel filter housing, because I can’t find one anywhere. Lots of generic items out there but none seem application specific. Looking at something like this:
Thanks!
Last edited by DoctorStoopid; Sep 24, 2023 at 04:37 PM.
Re: Replacing hard fuel line with rubber section/fuel filter housing size
There was a time when you could lookup every part a particular carburetor used just by providing the carburetor number. Does such a thing (used to be a parts book) exist anymore?
Re: Replacing hard fuel line with rubber section/fuel filter housing size
Originally Posted by paulo57509
There was a time when you could lookup every part a particular carburetor used just by providing the carburetor number. Does such a thing (used to be a parts book) exist anymore?
If there is a book, I wish I had it, because I’ve got a new problem now.
I was finally able to remove the inlet after cutting a greater section off and slamming a 5/8 socket on there with a breaker bar, and I noticed that there’s a little rubber gasket within the fuel filter housing.
I’ll need a new inlet line so I picked up this dorman replacement (which isn’t the right size and has to go back to the parts store) which has the o-ring on the line itself:
What I removed from the stuck 5/8 threaded fitting, however, looks like this:
I don’t know if that o ring is SUPPOSED to be attached to the fuel line or supposed to be attached to the filter housing, but I know that the filter housing I ordered ain’t got it.
Can anybody weigh in on what I should be looking at with that gasket?
I also realized the reason (or at least one of the reasons) I was leaking gas constantly was because the little nylon gasket between the carb body and filter housing was simply not there at all so I guess this fuel like break was a blessing in disguise: I would have never noticed it otherwise.
Re: Replacing hard fuel line with rubber section/fuel filter housing size
Yeah whatever you have in that pic with the O-ring, that's a power steering fitting. Typical Saginaw O-ring setup. Not the right thing for a carb at all.
Carbs always have yerbasic inverted flare like the last pic. Stuuuupid eeeeezzzzy to create yerself with yerbasic double-flaring tool (folds the tubing over inside itself, then flares it, such that there's 2 layers of metal where the nut clamps it, as you see in yer pic). Get one. Once you get used to using it, it's AMAZING how often you'll run into uses for it.
Can't answer about "book". Not sure there ever was one, but if there was, all the GM part #s are LONG GONE. These cars are ANTIQUES: older than 25 years. Any kind of "book" you find is gonna be ... worthless. Wrong line of inquiry. Instead, learn to deal with the generic properties of the parts you're working with. In this case, 3/8" tubing, inverted flare.
The pic you had at first, with that big brass nut and the thin nylon gasket, is the right thing. It's also inverted flare where the line goes into it; just like stock. If your stock line wasn't pre-destroyed you could just hook up to it. Oh well.
Problem you now have is, the place you need to put the rubber hose splice, is about the WORST POSSIBLE spot to do that, because of the bend in the line pieces that are left.
Here's what I ended up doing on my own car some decades ago in a somewhat similar situation. Exactly the same except different. I flared the OE steel line as described, then used a section of braided line and its fittings to hook from the carb to the remains of the steel line. I'd suggest that some similar approach is probably best in your situation.
I'd recommend PTFE line and the fittings specific to that type of line.
Re: Replacing hard fuel line with rubber section/fuel filter housing size
Originally Posted by sofakingdom
Yeah whatever you have in that pic with the O-ring, that's a power steering fitting. Typical Saginaw O-ring setup. Not the right thing for a carb at all.
Carbs always have yerbasic inverted flare like the last pic. Stuuuupid eeeeezzzzy to create yerself with yerbasic double-flaring tool (folds the tubing over inside itself, then flares it, such that there's 2 layers of metal where the nut clamps it, as you see in yer pic). Get one. Once you get used to using it, it's AMAZING how often you'll run into uses for it.
Can't answer about "book". Not sure there ever was one, but if there was, all the GM part #s are LONG GONE. These cars are ANTIQUES: older than 25 years. Any kind of "book" you find is gonna be ... worthless. Wrong line of inquiry. Instead, learn to deal with the generic properties of the parts you're working with. In this case, 3/8" tubing, inverted flare.
The pic you had at first, with that big brass nut and the thin nylon gasket, is the right thing. It's also inverted flare where the line goes into it; just like stock. If your stock line wasn't pre-destroyed you could just hook up to it. Oh well.
Problem you now have is, the place you need to put the rubber hose splice, is about the WORST POSSIBLE spot to do that, because of the bend in the line pieces that are left.
Here's what I ended up doing on my own car some decades ago in a somewhat similar situation. Exactly the same except different. I flared the OE steel line as described, then used a section of braided line and its fittings to hook from the carb to the remains of the steel line. I'd suggest that some similar approach is probably best in your situation.
I'd recommend PTFE line and the fittings specific to that type of line.
Thanks for the reply!
I’m not certain this is a power steering fitting. It came straight off the Rochester and looks nearly identical to the initial picture I posted save for the gasket around the center. I took a new picture that looks more similar to the replacement I posted up top:
The only real difference I can see between the replacement part I haven’t yet received and this filter housing I removed from my carb is that gasket. Are these totally different parts?
Re: Replacing hard fuel line with rubber section/fuel filter housing size
The brand-new Dorman piece with the O-ring on it is the thing I was referring to as a power steering part, not the fuel filter housing.
There's no "little rubber gasket" in the fuel filter housing. What you're seeing, that dark-ish discoloration, is merely where the flare fitting on the end of the steel line, was seated on it. There is no gasket in a flare fitting. It's all metal-on-metal. The material the line is made of seals directly against the seat in the fuel filter housing.
Re: Replacing hard fuel line with rubber section/fuel filter housing size
Originally Posted by sofakingdom
The brand-new Dorman piece with the O-ring on it is the thing I was referring to as a power steering part, not the fuel filter housing.
There's no "little rubber gasket" in the fuel filter housing. What you're seeing, that dark-ish discoloration, is merely where the flare fitting on the end of the steel line, was seated on it. There is no gasket in a flare fitting. It's all metal-on-metal. The material the line is made of seals directly against the seat in the fuel filter housing.
Oh what a nightmare this is becoming. I'll go the braided line route when the weather gets a little better next spring, but for now I'm trying to fabricate something that'll work for the time being. My hang up is, since I destroyed the fuel line nut getting the line off, I need a replacement for an improvised cut-and-flared line that I'll be using to go from the inlet to the fuel hose to the remainder of the hard line still in tact. I believe this is the part I'm looking for, or something like it, but I can't tell what additional measurements I need to verify the thread size.
Every hardware store I've been to refuses to stock a 5/8 - 18 nut with a 3/8 bore so I don't know if I'm losing my mind or it's just a piece EXCLUSIVELY used on Rochester carbs, but any advice wolud be appreciated. If I could stroll down to ACE hardware and get this thing, I'd be on the road TODAY.
Re: Replacing hard fuel line with rubber section/fuel filter housing size
No actually it's an EXTREMELY common nut, or at least, WAS at one time.
For reasons above my pay grade, instead of describing it as WHAT IT ACTUALLY IS, which is "3/8" inverted flare nut", they've gone to describing it by its threads. Moronic. Be that as it may, you can probably get it at ANY parts store, or Home Depot or the like.
Another way to get it is to go to any parts store and pick up a stick of 3/8" brake line. For example https://www.autozone.com/brakes-and-...line/85331_0_0 Then just cut off however much you need and hook it up. These things are all SO GENERIC, it's hard to grasp how the people who sell them, feel a need to make it SO DIFFICULT.
I STRONGLY suggest that you get the "good" rubber line, aka "fuel injection line", rather than the cheeeeeeep "fuel line" which will put a ready-made source of gasoline-fed FIRE under your hood. At least you'll get a little longer with the FI line before your car unexpectedly burns itself to the ground out of the clear blue.
Re: Replacing hard fuel line with rubber section/fuel filter housing size
I went ahead and spliced the line in but it sits way too close to the heater hose coming off the heater control valve for my comfort. Runs fine and doesn't leak for right now but this fix is going to be extremely temporary. I'm just going to go ahead and order a new line. I've spent more money trying to do this on the cheap than to do it right the first time (as these things go).
I noticed Classic Tube has lines listed for 1986 here
But I don't see any listing for pump to carb on 1987 here
If I were to order the line for 86, that should be OK, I'm guessing?
Re: Replacing hard fuel line with rubber section/fuel filter housing size
Yes it will work, it's the same. Was the same for LOTS of cars for many years in that time frame. Not just F bodies; A, G, & B bodies too. Probably trucks as well.
Be aware that to change it, the WP will have to come off. Good time to refresh that while you're at it.