Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   General Miata Chat (https://www.miataturbo.net/general-miata-chat-9/)
-   -   bursting fuel lines (https://www.miataturbo.net/general-miata-chat-9/bursting-fuel-lines-7599/)

trito 02-20-2007 04:26 PM

bursting fuel lines
 
Hi,

I just installed a Walbro 190 HP and my fuel inj lines keep developing leaks. At first I thought it was because the stock lines were crap so I bought some good year 50 psi tubes and those burst too. Do I need stronger tubing? My fuel set up also includes Jim B's dual feed rail which I also recent installed.

Newbsauce 02-20-2007 04:38 PM

put on a pressure gauge and see at what point they are bursting... I know when I put on my walbro 190 mine were bursting around 120 psi due to the fact my AFPR was messing up and jacking up my fuel pressure. I run around 100 psi-ish now and they seem to be holding up just fine.

*edit* I just use the fuel line they have at Advanced Auto.. I forgot the part number but its extremely cheap and they cut it by the foot.

bripab007 02-20-2007 04:46 PM

I bought hose rated for 250 PSI at West Marine for real cheap. It's got Uber-thick™ walls!

UofACATS 02-20-2007 04:56 PM

If you just ask for fuel line, sometimes they slip you the 50 psi stuff. The 190 can than double that. Get some of that Uber stuff ;)

Ben 02-20-2007 04:59 PM

you need fuel injection hose, not regular hose. then make sure you push it up the hard fitting as far as possible and clamp it with a worm clamp.

Atlanta93LE 02-20-2007 05:00 PM

Make sure you use fuel injection line, not simple fuel line. Fuel injection line is made for pressurized systems, where normal fuel line is for cars with carburetors, or for the unpressurized parts of a return fuel system. (You beat me to it, Ben)

I was shocked at the price of fuel injection hose.

UofACATS 02-20-2007 05:11 PM

Uber looking good:

http://www.westmarine.com/webapp/wcs...allpartial/0/0

$2.79/ft. I do believe that's cheaper than the fuel injection line I purchased.

trito 02-20-2007 05:11 PM

yeah they are fuel injection lines, they have a double layers with a mesh inbetween plus an addition blue lining in the middle. They are rated at 50 psi. I haven't installed the turbo yet or the AFPR, car is stock other than the fuel pump and fuel rail. I guess I'll look into the "uber" lines. Do I need to replace the rubber lines at the pump as well or just in the engine compartment?

Thanks,

t.t.

trito 02-20-2007 05:17 PM

are these good enough?

http://www.amazon.com/exec/obidos/AS...o-20/ref=nosim

Ben 02-20-2007 05:19 PM

where does the leak occur? in the center of a section of hose, or where the hose meets a fitting?


wish i had known about the west marine hose for $3/ft. they have a store not too far from me

trito 02-20-2007 05:25 PM

first one burst about 4" from the end, the 2nd burst was about 2" away

olderguy 02-20-2007 05:26 PM


Originally Posted by trito (Post 84816)
yeah they are fuel injection lines, they have a double layers with a mesh inbetween plus an addition blue lining in the middle. They are rated at 50 psi. I haven't installed the turbo yet or the AFPR, car is stock other than the fuel pump and fuel rail. I guess I'll look into the "uber" lines. Do I need to replace the rubber lines at the pump as well or just in the engine compartment?

Thanks,

t.t.

50psi is an awfully low rating.

jayc72 02-20-2007 05:59 PM

I thought that standard FI hose was 100psi? And that the other hose (50psi?) was for carbs?

Ben 02-20-2007 06:18 PM

yeah I think he has fuel hose, but not fuel injection hose.

BenR 02-20-2007 06:56 PM


Originally Posted by trito (Post 84816)
They are rated at 50 psi.



Stop that.

How much pressure did you plan on running?

trito 02-20-2007 07:31 PM

Yeah I guess I should have been more explicit, I ask for Fuel Injection hoses and they gave me these. I didn't check the max pressure till after it burst. I ordered some from West Marine, hopefully that will fix this.

Another quest, do I need to replace the stock tubing going out of the fuel pump as well? These didn't burst on me but I wanted to see if I should replace them anyway (I bought 10' just in case).

UofACATS 02-20-2007 08:02 PM


Originally Posted by trito (Post 84858)
Another quest, do I need to replace the stock tubing going out of the fuel pump as well? These didn't burst on me but I wanted to see if I should replace them anyway (I bought 10' just in case).


Well, you didn't replace that tubing with the 50psi stuff so in theory it should be fine. Plenty of Walbro equiped, boosted miatas running around that I've never heard any problems from. However, you'll be replacing a lot of the fuel line with the new Uber stuff, and that line is probably pretty old, so why not? Peace of mind at least.

Braineack 02-21-2007 09:24 AM

Regular "fuel injection line" (SAE30R9) is required to have higher working pressure rating (125psi) and minimum burst pressure rating (900psi).

If your hose has a number of R7 and R8 it is only a medium pressure hose, but should be OK.

R6 and below and it's only "fuel hose" made for CARB cars, only 40psi working.



you can easily feel the difference in SAE30R6 & SAE30R9, it's like cooked vs. uncooked spagetti.

PAT! 02-21-2007 10:44 AM

Most performance fuel line will have a ~300 or so operating pressure and a burst rating 3 or 4 times higher. You bought crap, replace it.

If you use the correct components clamps aren't even needed until you go above 150psi.

trito 02-26-2007 01:52 PM

Hey guys just an update. I got the tubing from Marine West (thanks Brian). The tube wall is almost double the size of what I had!
Everything is working fine now.


All times are GMT -4. The time now is 03:25 PM.


© 2024 MH Sub I, LLC dba Internet Brands