‘97 4.3 2bbl to 4bbl!

[jkimball]

Well, all of my parts have finally made their way in and I have everything other than the fuel line ready to do my swap.
-Edelbrock 1409 carby
-Edelbrock 2519 intake
-K&N 59-3264 Flame Arrestor
-New gaskets & intake bolts
-ARP Carb studs
-Jegs Billet Dist. Hold down
-Merc. Cap/rotor
-Delco MR43LTS plugs
-8mm wires
-Merc. Fuel filter
-160* thermostat/housing/gaskets
-also taking the opportunity to freshen up all rubber water hoses, and update the circ. Pump hose to the one with a drain in the elbow & change oil.

Overall I feel like I have a pretty comprehensive list to do this job and other PM while I’m at it. Am I missing anything? I may also add A true PCV to the rear vacuum port to help evacuate some blow-by fumes/oil while under load

Also just replaced both the black/grey trim hoses, the trim manifold and all 4 braided lines last night. That was a bit of a beast due to corrosion on the braided lines and having to fish the lines through the transom, but it’s done!

A lot of work on Her to get her up and going for the summer (also doing new T-top canvas & seadek today, but that’s for another posting section:joyous

Other than asking if I’m missing anything, my only question is regarding fuel line. What have those that have swapped done for lines? Did you bend a new metal line (what material? SS, steel, Nickel/copper?) or did you use USCG approved A1-15 rubber line and clamps? If so, where did you find the male nipples for the carb/fuel pump?

 

[Scott Danforth]

I have done both bending up new metal lines as well as A1 soft hose

 

[jkimball]

I have done both bending up new metal lines as well as A1 soft hose

Thanks Scott,
After a little digging, I found that Sierra actually makes pre-fabbed replacement rubber lines in two sizes: 25" (P/N 18-8115) & 31" (P/N 18-8114)
Both come with the 5/8 inverted attachments for both fuel pump and carb. This seems like it may be the ticket! Any experience or input with them?

I was really hoping to find an OEM Merc./Quicksilver metal line for the '97+ 4bbl webber applications, but they're NLA everywhere I turn.

 

[Scott Danforth]

Its a $5 3/8" brake line available at any auto parts store

 

[jkimball]

Its a $5 3/8" brake line available at any auto parts store

The Sierra part?

 

[Scott Danforth]

no, the metal line that you will bend up. the Sierra part is $50-60 depending where you buy it from.

but hey.....its your money.

 

[jkimball]

no, the metal line that you will bend up. the Sierra part is $50-60 depending where you buy it from.

but hey.....its your money.

Oh I see.
I was just assuming by the time I bought the bending, glaring tools and metal line I would come out about the same in the end.
Aside from cost - would there be any benefit to the metal line over the A1 rubber?

 

[Lou C]

The rubber gives you more flexibility with the mounting of the fuel pump but if possible I'd rather have metal between the pump and the carb. If you do go with metal, when threading on the fittings, have the carb and fuel pump mounting a little loose, that allows you to get enough movement to make it easy to thread the fittings on without stripping anything .

 

[Scott Danforth]

Oh I see.
I was just assuming by the time I bought the bending, glaring tools and metal line I would come out about the same in the end.
Aside from cost - would there be any benefit to the metal line over the A1 rubber?

you shouldnt need flaring tools as you can normally buy the length you need, however the bending tools are recommended.

metal will last decades, the rubber will last about 15 years

 

[jkimball]

The rubber gives you more flexibility with the mounting of the fuel pump but if possible I'd rather have metal between the pump and the carb. If you do go with metal, when threading on the fittings, have the carb and fuel pump mounting a little loose, that allows you to get enough movement to make it easy to thread the fittings on without stripping anything .

Thanks for the tip! That makes a lot of sense.
I’m anxious to get this setup on her and see how she does but waiting on my son to get home Friday so he can help and learn

 

[jkimball]

you shouldnt need flaring tools as you can normally buy the length you need, however the bending tools are recommended.

metal will last decades, the rubber will last about 15 years

I see, that makes sense.
I’m assuming that the threaded fitting on the end of the pre-flared tubing will be the same size that threads into the carb and fuel pump

 

[Scott Danforth]

I see, that makes sense.
I’m assuming that the threaded fitting on the end of the pre-flared tubing will be the same size that threads into the carb and fuel pump

yes, 5/8" inverted flare is paired up with 3/8" metal lines

 

[jkimball]

yes, 5/8" inverted flare is paired up with 3/8" metal lines

Awesome!
thanks for the tip. It’s easy to get sucked into the convenience of buying a prefabbed part at a premium price.
I will check NAPA tomorrow to see what they have. As for materials for metal lines, any preference? Steel, Nickel/copper, SS if available?

 

[Scott Danforth]

take a tape measure, measure the existing bent fuel line. should be either 24" or 30"

then go buy a pre-made steel brake line of that length. for about $5

use your old line as a guide to bend the new line

copper is not to be used on the fuel system even the 90/10 CU-NI

 

[jkimball]

take a tape measure, measure the existing bent fuel line. should be either 24" or 30"

then go buy a pre-made steel brake line of that length. for about $5

use your old line as a guide to bend the new line

copper is not to be used on the fuel system even the 90/10 CU-NI

Got it, thanks!
I think my new one is going to need to be a tad longer Bc of the location of the Edelbrock fuel port being in the rear vs the mercarb being in the front. But this has been helpful

 

[jkimball]

take a tape measure, measure the existing bent fuel line. should be either 24" or 30"

then go buy a pre-made steel brake line of that length. for about $5

use your old line as a guide to bend the new line

copper is not to be used on the fuel system even the 90/10 CU-NI

One more question as I'm thinking through the fuel lines. I cannot work on the boat right now bc it's pouring here in NE FL, so I don't have it right in front of me to confirm. But, as I think through the job, something occurred to me. The new Edelbrock has a nipple on the rear of the carb. above the inlet, I assume for a fuel return line. On the current 2bbl set up, I don't recall there being a return line from the carb. to the electric fuel pump.
What do I do in this case?

 

[Scott Danforth]

should be the small nipple for the fuel pump tell-tale hose. post a pic

 

[jkimball]

should be the small nipple for the fuel pump tell-tale hose. post a pic

Here’s a (stock) pic of the Edelbrock - nipple I referenced circled in red.
The other is my current setup, with no such provision or line running back to the electric pump.
nor is there a provision on the pump or fuel filter housing for a return.
What exactly do I do in this case?

 

[jkimball]

Any thoughts on how to approach what to do with the Edelbrock fuel vent/return line? With the electric fuel pump I don’t believe I have a place to run this line to.

 

[Scott Danforth]

cap it.