TheSamba.com :: View topic - 1977 Bay

Tue Apr 22, 2025 7:47 pm

While doing an oil change this weekend I'd like to relocate the fuel filter out of the engine compartment and will likely replace the old line at the same time. I've seen various fuel line sizes in my search of different threads and elsewhere (i.e., BusDepot and others). I looked through the books I have on hand as well and didn't see any mention of fuel line size there either.

It's a 1977 Bay, Type 4 with dual carbs. I can take off the existing and measure it, but being that we just got it, I would rather ask the question (as a bus owner newbie myself) than assume the previous owner had it right.

With that, is there a recommended size I should look to have on hand for the swap?

Tue Apr 22, 2025 8:04 pm

I don’t believe that USA market 1977 buses were available carbureted. Therefore, yours is probably a conversion from fuel injection and I’d guess that gates carbureted fuel hose is right for you in 5/16th size

Tue Apr 22, 2025 8:48 pm

If you can’t find what Aeromech posted. I use 1/4” FI fuel line. I also use 1/4” metal fuel filters, you should be able to find both at flaps.

Tue Apr 22, 2025 9:03 pm

1/4 is too small for Webers or dellortos. Works fine with Solex

Tue Apr 22, 2025 9:16 pm

If the '77 was originally fuel injected you have an outlet on the fuel tank that needs 7mm hose. Most electric fuel pumps use 7mm hose. If the carbs are Webers IDF or similar they use 7mm hose.

Wed Apr 23, 2025 8:48 am

Thanks for all the information.

aeromech is right, the engine was originally fuel injected and converted back to dual carbs (as far as I know 4-5 years ago). I believe the EMPI is a Weber 34 ICT reproduction.

I've included a few more pics for reference in case anything else jumps out at you all (I'm learning as I go).

So where it stands currently, I'll get 5/16" from flaps as you all confirmed some of what was there (currently SAE30R7). Sounds like I should also get a 7mm as well for the first stretch coming out of the tank. I'll then relocate the fuel filter underneath and out of the engine bay (should I relocate the Hep-02 pump as well?).

The line into the fuel filter is labeled different, this might be nothing or overthinking on my part but does it need to be that way? Couldn't I just use the 5/16" there as well?

These nuances send me down rabbit holes from which it's hard to return! My wife appreciates your help :)

Wed Apr 23, 2025 11:51 am

You're not really overthinking but: use 7mm everywhere, it will fit everything well. IMO 5/16" FLAPS hose will almost always be inferior to German made 7mm hose. Get the fuel filter located somewhere else, outside of the engine compartment. Use hose clamps that don't have holes in them.

Wed Apr 23, 2025 5:33 pm

1/4” works perfect on my engines and I have the filter on the bay. :shock:

Wed Apr 23, 2025 6:03 pm

7mm is 9/32". 5/16" is only 1/32" more. Use the right clamp and you will be fine with 5/16"

Wed Apr 23, 2025 6:32 pm

richparker wrote: 1/4” works perfect on my engines and I have the filter on the bay. :shock:

Yeah. Been filter in the engine compartment, sometimes two, one dedicated to each 34 Weber, for almost 30 years.
Leaving the filter under the bus (like the factory 2.0 F.I.)vulnerable to road debris & gravel/twigs/logs what have you gives me the willies. I use a support strut from the old factory Solex set up as a support arm for the mainline holding a see-through plastic filter. WIX is my preferred brand lately. So far, so good.

Thu Apr 24, 2025 6:30 am

timvw7476 wrote: richparker wrote: 1/4” works perfect on my engines and I have the filter on the bay. :shock:

Yeah. Been filter in the engine compartment, sometimes two, one dedicated to each 34 Weber, for almost 30 years.
Leaving the filter under the bus (like the factory 2.0 F.I.)vulnerable to road debris & gravel/twigs/logs what have you gives me the willies. I use a support strut from the old factory Solex set up as a support arm for the mainline holding a see-through plastic filter. WIX is my preferred brand lately. So far, so good.

just use the metal fuel filter from the FLAPS and you never have to worry

to the OP make sure you buy quality hose that is rated for modern fuels SAE 30R14, like Gates barricade, and it will be good for several years