Hey guys -

Been thinking about this a while.

Mazda uses a REALLY nice grade of fuel hose. Fits VERY snugly, lasts a long time, works with the stock squeeze-type hose clamps, etc.

Most aftermarket fuel line is inch and not metric size, which is a problem to start with. Also, a lot of it is pretty thin wall compared to the OEM stuff.

The OEM fuel line is CRAZY expensive. For example, the short piece going from the fuel feed metal lines to the primary fuel rail is about $36 for 6 inches worth of line. Yowza! That piece, as well as the other lines to the rails, can be bought with the fuel line recall kit for a much better price. But, some lines, like the lines from the undercar metal lines to the engine, are also crazy high from Mazda.

Coolant and fuel lines are one thing I don't mess with on an FD. The coolant hoses are no problem, Mazda has those for reasonable prices and the new design ones are VERY hardy and will last for years to come. The fuel line is also really hardy, but some times it's nice to have a good source for the stuff by the foot brand new.

So, anyone ever found anything? I'm fixing to do a little Googling myself.

Dale

 

Dale,

It isn't often you get to ask the forum for help. I did a google search and came up with these links:

http://www.international-auto.com/me...y-the-foot.cfm
http://www.dssales.net/CIS.html
http://www.dssales.net/FUEL.html

Other than scoping out these sites, no additional research was done. At least this is a good start!

George

 

as you may know in my build thread, i completely relined my fuel system. i was very pleased with the 5/16th line stainless steel braided from summit, that i ended up rewiring the whole under the car from the fuel pump to rails in it.

I have a upgraded secondary fuel rail, so idk about oem replacements, ive just had alot of success with installing that ss braid line.

 

Dale, did you ever have any luck tracking down good fuel hoses? I'd like to replace all my fuel lines, but the fuel recall kit isn't available anymore, and the stock lines are pretty expensive.

A lot of the recommendations I see are SS braided or PTFE lines, but I think most of those require special fittings to be installed.

 

I haven't that I can remember.

Big thing is metric fuel hose, I THINK it's 8mm ID hose.

Dale

 

 

Fuel line tends to be a pain to work with, but I really dislike the metal braided stuff because it can slice up the other things in the engine bay. I've used Parker SAE 30R3 hose, 5/16" ID which should be about 7.93mm. It's been on the car for about 8-9 years, I seem to remember it fitting well enough, and it appears to be holding up OK. I got it from McMaster-Carr but I don't see it on their current website. This looks like the same thing, but I've never bought from this website so you may want to find a local supplier. https://www.shopcross.com/product/pa...r3-516-id-hose

 

Thanks Scotty, that pointed my search in the right direction I think. It looks like 30R3 is an older fuel line standard, which is probably why not too many places supply it any more. It looks like gates and goodridge both make SAE J3OR14T2 lines that look to have good specs for our cars (225 psi rated, 257F degree continuous temp, 302F burst), seems to be compatible with the stock spring clamps.

Seems like the best option without switching to AN fittings or new fuel rails is to pay up for the OEM banjo hose line, and use this stuff for the generic hoses.

 

That's good to know about the updated fuel line standards, thanks.

 

I am looking to do a fuel system upgrade and looking at using the Earls Ultra Pro Series hoses with twist on fittings. Anyone ever tried using these and have a long term review?

 

This is what I have used in the past on old BMWs (not on an RX-7).



I can't say how it compares with Mazda's OEM hose, but is is higher quality than you can get from most auto parts stores and it comes in metric sizes. You can purchase short lengths of it at BelMetric.com

 

IMO, size is more important than the material. I used SAE and it leaked (double clamped)

(standing by for responses on size being important)

 

I just bought 3/8 Al tubing and AN-6 fittings to completely replace my fuel lines. Got it all from anplumbing.com. They also make braided lines and connections to order. Ill post pics in my build thread one of these days. I'm not quite finished. The extra mm in diameter over stock lines is proving difficult to fit into the stock plastic under-car clips.

 

I currently use 5/16" hose and it fits snug and clamps without leakage.

 

Bumping this up as I'm about to replace my fuel hose.

Here we are in 2019, anyone have a recommendation on what fuel line to get and where?

and wondering if I should double up on the oem spring clamp or use 1 oem spring clamp and 1 fuel clamp.

 

The russell pro classic 2 with the nylon braid in -6 is what I've been putting in my cars. It's a very very snug fit over the stock hard lines. So much so that I had to lube it to get it on. It does rotate freely once it's on though. I think its just the rigidity of the wall of the hose itself. The stock squeeze clamps don't fit that well over it so I went with the band clamps and I've been very happy with it.

 

I ended up using Gates Barricade in 5/16. Snug fit and no leaks. I used new Mazda spring clips on everything, not sure how well it would work with old worn out ones.

 

Thanks for the info guys.

Any other recommendations? Will probably order some on Friday.

 

 

A few points:

- Fiber reinforcement type: Mazda had fuel hose issues as evidenced by the recall kit and upgraded hoses to fix failed hoses. My guess is they started with nylon reinforced and went to Aramid fiber reinforced. Aramids are your high performance heat resistant variety such as Nomex. I would look for a hose with either a very high continuous temperature rating well in excess of engine bay norms or something that specifically says it is reinforced with Aramid fibers (Gates barricade 27335 specifically says aramid fiber). Based on the comparable temp ratings, Flennor is probably Aramid as well.

- Spring clamps: I have had issues using mazda spring clamps on hoses that are not mazda. Not enough tension when on or won't go over the hose without bending them out. The spring clamps are designed for a specific hose OD, not the hose ID. I have seen large variances in hose OD's between manufacturers. I use all stainless HD worm gear clamps sized for the OD of my hoses.

- I personally used the Mazda fuel recall kit for engine hoses and a standard Dayco 80084 5/16 SAE30R9 hose from Summit for items further from the engine. The Dayco does not specifically state Aramid, but gives a max temp of 300deg F.