Mercruiser edelbrock

[Bibapulula]

I am trying to tune my Edelbrock 1410 on my Mercruiser 7.4L 310HP. What jets, springs and metering rods should i use?

 

[alldodge]

Have a look thru the manual, and if after reading thru we can see if additional help is needed.

https://www.edelbrock.com/pub/media/wysiwyg/documents/carb-owners-manual.pdf

 

[Bondo]

I am trying to tune my Edelbrock 1410 on my Mercruiser 7.4L 310HP. What jets, springs and metering rods should i use?

Ayuh,...... Welcome Aboard,...... What's in it now,..??

What symptoms are ya tryin' to fix,..??..??

 

[Bibapulula]

Hello!

It stumbles in the midrange when the secondarys beginns to open and runs a bit rich.
I I read on the following page that weber used a completely different set of jets, rods and springs on the mercruiser 7.4.
What is the difference between edelbrock and the weber?

https://www.carburetor-parts.com/Weber-Marine-Jet-Sizes_ep_486.html

 

[Bondo]

What is the difference between edelbrock and the weber?

Ayuh,....... The name on the side of the casting,......

'n Edelbrock parts are waayyy cheaper, as well as easier to get,.....

 

[NHGuy]

The Edelbrock is a "re-pop" of the Weber. The parts mostly interchange. I have a lot of Edelbrock stuff that I have used in my Weber.
If you want to learn how to tune it the old way go through the Edelbrock webpage. It does work. But it takes a lot of time and spark plugs.
If you want to be quicker get an Air Fuel Ratio setup, measure the outputs and do it the "new" way. It's a lot less frustrating. A ton less trial and error.

 

[Bibapulula]

Thanks, air fuel meter would be the best but hard to find a place to put the o2 sensor. My Edelbrock 1410 is stock with 0.113 primary jets 0.107 secondary jets, rod 71-47 and orange spring. Weber specified 0.107 primary, 0.98 secondary, Rod 65-42 and Pink spring. I think i will try that setup and see how it runs and check the spark plugs. Weber setup would not be that much leaner because of the smaller metering Rod?

 

[NHGuy]

Correct. Smaller jet and smaller rod is pretty close to the original set. both ways the primaries have a .042 gap difference.

BUT the secondaries are just jets and the .107 jets are 9% bigger. It's more work, but change the secondary jets first and run it.
Also make sure you have no leaks in the intake manifold/gasket, carb base gasket, carb body seals, or anywhere else.

Is your boat propped to get 4600 rpm at wot? If not the transition to the secondary barrels can be rough as the engine struggles to make rpms under too much torque load.

What is the timing set to?

Be sure the choke opens when the engine is warm. But it's more likely an air leak or wrong jetting/springs/rods.

if things don't not seal well you won't get enough vacuum to actuate the primary rods right or the secondary air doors either.

 

[NHGuy]

Here's a book of carb settings I just remembered I had saved. WFB is their acronym for Weber Four Barrel. I think they were also Carter AFB at one point where AFB is Aluminum Four Barrel.

 

[Bibapulula]

I have changed the jets, rods and springs to 0.107 primary, 0.98 secondary, Rod 65-42 and Pink spring. Runs great but according to my fuel flow meter it consumes more fuel than before. I also tryed to changed the springs to the original orange coloured. Less fuel consumption but a bit of hesitation when the secondarys opens. Guess i will have to live with the higher fuel consumption if i want the engine to run right. The boat is a 2855 and consumes around 3,5 liter/nm (1gal/nm).

 

[Scott Danforth]

fuel consumption for a spark ignited motor in good tune without leaks should be 0.4# per HP per hr.

your 310hp is prop rated, about 350hp at the crank

so assuming your commanding 300hp, you should be burning 120# of fuel per hour, or about 17.6 gallons per hour.

 

[NHGuy]

Nice, you are going the mile to get things dialed. Even if you aren't thrilled with fuel consumption you can be comfortable that the engine doesn't run lean, which ruins things.