Mounting fuel lines on fuel tank - Page 1
Forum section: electronics / general

author: Zeyneb
author_rank: Regular Contributor
timestamp: July 30, 2023, 12:22:14 pm
content: Hi there,Who would like to help me for a good way to mount fuel lines on a fuel tank? Please see the photo of the fuel tank to understand what I’m talking about. It’s about mounting the 3 lines on the right. This fuel tank is from a 1997 Toyota Starlet. Toyota originally had an annoying plastic hose separator clip that is still visible in the photo. But I want to get rid of that thing and make something better.The objective is to mount two 6.35mm diameter fuel lines and an 8mm hose (the center one), on the fuel tank at that position. The mounting has to be equipped with rubber lining so vibrations will not damage the fuel lines. And I would line to be able to remove the assembly in the future without breaking anything. The lines are spaced 15mm from each other.My plan so far is to use this P-clip material that can easily be bent straight. Then have a top and bottom strip and make U bends to accommodate for the fuel line clamping at the right diameters and positions. But the problem is that with this 1.1mm thick galvanized steel I cannot make the bends sharp enough for the 15mm spacing that I need. As I do need a notch between the lines so the lines cannot move toward the center hose.Regarding mounting on the tank. Please see picture rect_mounting_point.jpg. I can grind away this little bracket and make two new ones just like that and weld those on the tank to mount the strips mentioned in the previous paragraph. To avoid endless discussions about safety when welding on a fuel tank, I’ve already welded on this tank in a safe way and I’m still alive. I would like some advice on the mounting of the fuel lines instead.How about going for thinner strips of steel like 0.8mm? The EPDM rubber lining will work just as well on thinner material. Maybe aluminium or brass strips? Also I can fold around drill bits to get to the right diameter.

author: langwadt
author_rank: Super Contributor
timestamp: July 30, 2023, 12:32:08 pm
content: what's the problem you are trying to solve?Toyota are usually pretty good at getting things right and it already lasted +25 years so...

author: Zeyneb
author_rank: Regular Contributor
timestamp: July 30, 2023, 12:41:13 pm
content: langwadt,You disagree with my plan, fine. Let's wait for someone else who do want to help me. I think I was pretty clear in what my objective is.

author: coppercone2
author_rank: Super Contributor
timestamp: July 31, 2023, 04:54:00 pm
content: If you want a robust solution then mill out some steel to fit the lines. I would drill correct size holes in something then cut it in half. Slightly oversized if you want rubber inlay with split tubing or grommets. Then bolt it together. I feel like you can make it out of a 3/8 inch flat bar.

author: Zeyneb
author_rank: Regular Contributor
timestamp: July 31, 2023, 05:17:27 pm
content: Quote from: coppercone2 on July 31, 2023, 04:54:00 pmYeah thanks, that make sense. I do not have a mill but I can indeed drill oversized holes in two separate bars pressed firmly together in a drill vice. Then grind away much of the space between the holes so the strips can transition smoothly from hole to hole.Today at the DIY car repair shop I found that 0.8mm steel strip seemed too weak. I now have some 0.9mm stuff that is much more rigid. Does 0.9mm sound right to you for this application?

author: Gyro
author_rank: Super Contributor
timestamp: July 31, 2023, 05:25:56 pm
content: Be careful of creating moisture and rust traps, the existing plastic support looks to be a (deliberately?) very open construction.

author: Zeyneb
author_rank: Regular Contributor
timestamp: July 31, 2023, 05:40:02 pm
content: Quote from: Gyro on July 31, 2023, 05:25:56 pmInteresting point. I don't know how to deal with that yet. You understand my design with a top and bottom strip and rubber lining in between, right?

author: floobydust
author_rank: Super Contributor
timestamp: July 31, 2023, 06:56:11 pm
content: Quote from: Gyro on July 31, 2023, 05:25:56 pmI though it was loose on purpose, so a collision would not break the tubing in a crumple.

author: Stray Electron
author_rank: Super Contributor
timestamp: July 31, 2023, 06:57:53 pm
content: Quote from: Zeyneb on July 30, 2023, 12:41:13 pmUmm. No, it's not clear what you're objective is here, other than to just change the design to something else. I agree with Langwadt; unless there is a good reason to change the design I would leave it as is. Toyota's design should be more than adequate.OTOH a couple of nylon zip ties would probably work just fine, even if they don't look particularly elegant.

author: Zeyneb
author_rank: Regular Contributor
timestamp: July 31, 2023, 07:15:36 pm
content: Quote from: Stray Electron on July 31, 2023, 06:57:53 pmMultiple taps on that plastic thing are already broken. My objective is, among other things, something that can be disassembled in the future without breaking anything.

author: HighVoltage
author_rank: Super Contributor
timestamp: July 31, 2023, 08:07:07 pm
content: If you must, take a look at race car or "performance" fuel-line clampsBut there is nothing wrong with these original Toyota clamps, you would not really gain anything from changing this.

author: coppercone2
author_rank: Super Contributor
timestamp: July 31, 2023, 08:42:36 pm
content: oh yeah I did not think about compliance. springy helps there

author: Gyro
author_rank: Super Contributor
timestamp: July 31, 2023, 08:48:32 pm
content: Quote from: Zeyneb on July 31, 2023, 05:40:02 pmYes, I get the idea. I just don't know how much moisture might get trapped between the rubber and the pipe, or even what the pipes are made of and their succeptibility to corrosion. I once had both drive shafts on my car fail, one at a time, because water (and salt) had got under the rubber mass dampers and corroded the steel underneath.

author: floobydust
author_rank: Super Contributor
timestamp: July 31, 2023, 09:12:19 pm
content: Anything involving metal is going to corrode. It might be easier just to go to a wrecking yard or look at1997 StarletEP91- Clamp, Fuel Tube, for the part number, or something close enough to mount.If you can't find the part, then a similar one maybe for 4-5 lines or a RAV etc. can work.

author: Zeyneb
author_rank: Regular Contributor
timestamp: August 04, 2023, 07:10:50 pm
content: Hi there,I'm making some progress with the multiple fuel line clamp. I've made some dies to form the sheet metal accurately to the correct diameters. I found the holes where a little too large but when I insert smaller diameter drill bits I do get clamps to clamp firmly on the fuel lines. Also I found the P-clip material not suitable to bend around these sharp corners but I can superglue pieces of 1mm thick Viton rubber on the sheet metal. That did work well on a test piece that I made first.Some people might not find this worthwhile to put effort into. Well, up to them.

author: coppercone2
author_rank: Super Contributor
timestamp: August 04, 2023, 08:21:12 pm
content: I don't think super glue is the best thing to hold up to salt water that is likely to accumulate there

author: nctnico
author_rank: Super Contributor
timestamp: August 05, 2023, 09:30:50 pm
content: Quote from: HighVoltage on July 31, 2023, 08:07:07 pmAgreed. I'd just get a bunch of new clips (and some spares). There is at least 1 good supplier of Toyota parts in the NL (CAR in Nijkerkerveen) and likely there are others as well. Infinitely better compared to botching things and potentially create an even bigger problem.

author: Zeyneb
author_rank: Regular Contributor
timestamp: August 05, 2023, 10:23:14 pm
content: Quote from: nctnico on August 05, 2023, 09:30:50 pmI'm not listening to "advice" from people who aren't even looking into the topic. Your claim of "Infinitely better" is based on some subjective feeling.

author: Gyro
author_rank: Super Contributor
timestamp: August 06, 2023, 12:38:29 pm
content: Quote from: Zeyneb on August 05, 2023, 10:23:14 pmTo be perfectly fair, 'advising' using the correct spare part is deferring to to the car manufacturer's objective design.

author: HighVoltage
author_rank: Super Contributor
timestamp: August 06, 2023, 10:56:12 pm
content: Quote from: Zeyneb on August 05, 2023, 10:23:14 pmThat is too bad, because the people given you advise here are very qualified, as far as I can tell.That sheet metal bracket is NOT a good idea !Stay with the original Toyota clip or use an aftermarket clip that is made for fuel lines.

author: coppercone2
author_rank: Super Contributor
timestamp: August 06, 2023, 11:04:39 pm
content: I know why, its probobly designed to slip in a impact. All the rubber will make it sticky and it can get crushedI bet its hard to engineer one without crash testing the thing I assume it works with the crumple zone or something

author: mendip_discovery
author_rank: Super Contributor
timestamp: August 13, 2023, 08:07:04 pm
content: Sorry to the bearer of bad news but the Toyota solution is actually rather good, and your comments to people who said so, won't win you a lot of help.The p clip material you plan to use if likely to fail in the situation you plan to use it in.The way I have done it before it take a block of ally, drill some holes for the pipes then slice in half with the band saw.These days I would just use a 3d printer and make the two halves.Really simple solution is to have a bit of material with some holes to take cable ties and just tie the pipes to the board.

author: Gregg
author_rank: Super Contributor
timestamp: August 13, 2023, 08:38:06 pm
content: If you are looking for inspiration on brackets and other automotive fitments, just binge watch "Project Binky"https://www.youtube.com/user/badobsessionmsport/videos

author: mendip_discovery
author_rank: Super Contributor
timestamp: August 14, 2023, 11:49:23 am
content: Quote from: Gregg on August 13, 2023, 08:38:06 pmI like his version of CAD, it's so easy to use.