Help - Replacing fuel lines.

[TimC2520]

Well, I wanted to replace my fuel lines this weekend. That section from the water separating fuel filter under deck to the primer bulb on deck, up into the cowling.
It has 9 seasons on it and all markings are gone or never existed so I am not sure of the size.
I bought 3/8" from SIM, arrived today, but this looks like it is going to be much MUCH bigger than the section that I want to replace. I doubt this would fit through the rigging hole in front of the motor. Too tight with all the cables, hoses, wires, etc.
I was looking at the section from the Racor back to the tank and that sure looks similar in size to the 3/8" that's in my hand, but forward of the Racor, to the primer bulb to up into the cowling looks significantly smaller.
Everything is still OEM, 1999. Any ideas on the size needed and why I have 2 different sizes on each side of the Racor ??? :?:

 

[DaleH]

Could all be 3/8" ID line but I'd wonder if there wasn't mixed Type A1 rated fuel line on one side and Type B on the other. I have done this, putting fire-rated under gunnels, etc.

The A1 is more fire resistant and is much larger. I just measured a section of each I bought last year and go the following:

* A1 rated fuel line, of 0.375" ID, measures ~0.800" on the OD.

* B1 rated fuel line, of 0.375" ID, measures only 0.600" on the OD, and was surprised it was that much.

A1 Fuel Line Specs:
Trident Barrier Lined A1-15 Fuel Hose (Distribution, Return, Vent, and Transfer) for both gasoline (petrol) and diesel (including alcohol blends). Exceeds ABYC H-24 & H-33, SAE J1527, ISO 7840, & USCG Type A1; and is NMMA Type Accepted & CE certified. It is also compliant with CARB Regulations. Built with best fuel, fire and age resistant formulation, 2 spiral reinforcement and unique "Barrier Liner" on inside surface of tube so fuel is not in direct contact with rubber. Provides extraordinary resistance to fuel permeation and aging, as well as fire, heat, cold, and ozone. Also good bend-ability.

Newer A1 would be black in color with a red stripe.

B1 Fuel Line Specs:
Premium B1 fuel line hose. Thermo-plastic reinforcement gives excellent flexibility, bend radius, resistance to UV, cold, aging and permeation by all marine fuels including alcohol blends. Exceeds Newest Type B1 [USCG, SAE, ISO, and ABYC] Std. NMMA Type Accepted. CE certified. For I/B and I/O fuel systems, this is THE O/B fuel line hose for the domestic market and the ONLY one for the international market.

B1 is typically gray (now) but could be black of that vintage.

Looking at the END section of each straight on, the A1 appears to be double-walled, you'll see what I mean, as its 2-ply.

 

[TimC2520]

Thanks, I'll be down at the boat tomorrow, I'll take a photo and try looking on the blind side of the hose to see if any markings exist on the backside. The hose I bought is A1, double walled, I'd use it, if it'd fit through that rigging grommet on the front of the motor but I think it's going to be to large.

 

[Megabyte]

Excellent information Dale.
The OD size difference in the two 3/8" lines makes sense now.

 

[TomS]

I'm planning the same thing, plus going to replace the internal engine fuel lines as well.

I ordered the Yamaha fuel primer bulb asembly (all black hose), as well as the fuel line that runs through the rigging grommet to the engine mounted fuel filter (gray with red stripe), and everything through to the fuel rails. The fuel lines on the engine side of the fuel/water separator are all 5/16" ID.

Here are some dimensions for you, if it helps:

My 1999 Parker has 3/8" fuel line running from the tank back to the fuel/water separator. I purchased 3/8" A1 fuel line from Worst Marine.

Type A1 3/8" ID Fuel Line: .8" OD, .365" ID
Primer Bulb Assembly Line: .5" OD, .308" ID (5/16")
Internal Fuel Line (gray/red): .5" OD, .308" ID (5/16")

Here are a couple of pics as well.

-- Tom

 

[TimC2520]

Ahhhh, Tom, your boat must be rigged the same as mine.
I too have the 3/8" ID between tank and fuel/water separator. After that and to the engine, it must be 5/16" ID. Your photos look like what I am dealing with, the 3/8" seems "double walled" as Dale suggested.
Oh well, I'll have to re-order...this 3/8" will never fit through the rigging grommet on the front of the motor.

 

[DaleH]

After that and to the engine, it must be 5/16" ID.

No V6 motor should be running 5/16" fuel line ... at least 'above' 175hp anyway.

 

[TimC2520]

Funny you should mention that, the guy next to me has the same boat, just repowered and he has 3/8" now, used to have 5/16".
I will try to see if I can't squeeze this thing through that rigging grommet.

 

[TomS]

FYI, all the engine mounted fuel lines are 5/16" as well, so at some point you are going to have to step down from 3/8" to 5/16".

I'd rather make this connection using hardware that is designed for the task (ie a proper barbed fitting sized for 5/16" fuel lines at the F/W separator and stainless steel clamp) rather than inside the engine using one of the Yamaha plastic fuel joints or at the input side of the engine mounted fuel filter, both of which are sized for 5/16" fuel line, and both of which are secured with plastic wire-ties.

-- Tom

 

[TimC2520]

Another good point, decisions....decisions...
By the way Tom, I had the name you did for me finished...just waiting for decent weather to have it put on. I'll post pictures ASAP.

T

 

[TomS]

FYI, the Yamaha 5/16" hose is just under $30 from SIM. Part #2 in the diagram below.. its about 3' long.

-- Tom