95 370DA 7.4 carb replacement

A

ATC

New Member
Jul 7, 2008
76
New Jersey
Boat Info
1995 370 Sundancer (sold 2012)
Engines
Twin 7.4
Pulled my carbs to do a rebuild and found that they are shot (one broken screw, tons of rust, etc).
They are Weber 9780S carbs. I have had good luck with Edelbrocks in the past, and their 1410 marine carb looks like a direct replacement (square bore, layout, etc).
Appreciate any comments/recommendations before I proceed.

Thanks,


-Al
 
Edelbrock carbs are in my opinion one of the best carbs on the market. Their removable air horn allows for cleaning and quick jet changes if needed. One can also change needles without even removing the air horn. They seem to run well right out of the box with little to no adjustment. I wouldn't hesitate to use that on your application. 750 cfm should be more than enough.

Doug
 
Thanks Doug.

I feel the same about them, but haven't any experience with them in the marine environment. Just wanted to check with the "experts".

-Al
 
I just used the 1409 to replace a Weber 9600 which was shot. The only difference I think is 600cfm vs. 750cfm. I had to run a 12v source since the Edelbrock has an electric choke but other than that it was a direct replacement. I ran it a couple of times and only needed to make a couple of adjustments. Check the float levels as a lot of Edelbrocks come with them a bit off out of the box. In general I have had really good luck with them - I have a 1406 on my 74 Bronco and it's been fantastic as well. I got mine from Jegs and it was only $335. Good luck with the project!
 
Installed them this evening.

Interestingly enough (didn't know beforehand) the Edelbrocks ARE in fact Weber carbs! And for $327 each, a heck of a lot cheaper than a Mercruiser replacement (even the rebuild kits for the Webers go for about $100 each).
The replacement was seamless- everything fit perfectly. I did have electric choke before, so there was no pain here.
The only adjustment I made was a slight adjustment to the idle. Apart from that, a perfect fit!

Both engines sound/respond 150% better than they did before. I'll know better this weekend when I take her out. My only concern is in the jetting/metering and that it might be a bit "rich" for these engines.

Will post afterward.

-Al
 
ATC, where did you purchase the carbs? Are they new or rebuilds? Marine or auto?
 
ATC said:
Installed them this evening.

Interestingly enough (didn't know beforehand) the Edelbrocks ARE in fact Weber carbs! And for $327 each, a heck of a lot cheaper than a Mercruiser replacement (even the rebuild kits for the Webers go for about $100 each).
The replacement was seamless- everything fit perfectly. I did have electric choke before, so there was no pain here.
The only adjustment I made was a slight adjustment to the idle. Apart from that, a perfect fit!

Both engines sound/respond 150% better than they did before. I'll know better this weekend when I take her out. My only concern is in the jetting/metering and that it might be a bit "rich" for these engines.

Will post afterward.

-Al
Click to expand...

Good to hear. In my experience as well, Edelbrock carbs are jetted rich out of the box. I never swapped jets or needles because they ran fine but it was definitely slightly rich.

Doug
 
When I did mine I purchased the 4.3 v6 rods/springs but I agree they tend to run a little rich. I'm surprised it would run rich on a big block though - might need to adjust the idle mixture screws a bit. I found a good way to do this:

1. adjust your idle screw down to where the engine is just above stall - this lets you pick up on small changes in RPMs as you make changes
2. one at a time - screw the idle screws in to where the engine starts to run rough and then screw out until it evens out
3. adjust the idle back to your normal setting

It's easier on a car where you can connect a vacuum gauge and see the changes but after playing with it a bit by ear you can get it very close. This process will get your idle and your off idle acceleration to where you want it to be. If you're concerned with being able to get the carb back to factory specs you can always count the turns in on both sides and just record it. If you end up having any problems at mid-throttle or WOT then you can start looking at adjusting or changing the rods/springs which will allow you to compensate for more/less vacuum affecting the rods themselves. I doubt on a big block you will need to do this or even play with the jets. The good news is the rods/springs are easily swapped by just removing the spark arrestor and the hold down screw.

Congrats on getting these swapped out - enjoy that first ride!
 
If you have the Thunderbolt Ignition like we do you need to ground it (something like that) by taking the purple/white wire and grounding it, ideally to the battery. Set your screws/idle, unground.
 
The carbs were purchased through Summit Racing (website). The Edelbrock 1410 is a CG approved marine carb.

Thanks for the advice on the idle mixture.
 
You must log in or register to reply here.

Forum statistics

Threads
113,214
Messages
1,428,718
Members
61,110
Latest member
rvlewis
Back
Top