Trojan Boat Forum

I have a 1977 25' Express Cruiser. It looks to be the original 318 engine but currently has what looks to be the original carburetor. The gaskets on the carb. appear to be getting porous and I'm afraid of possible gasoline fume problems in the future. I Would like to replace this carb for this reason. Am not looking for performance due to the fact that 12 mph putting around the lake will be max speed. I am looking for the simplest replacement with the least amount of modifications necessary. The Edelbrock site has a 4 barrell carb. with electric choke; this seems to be the closest replacement available. Would this be a good carb to choose, and if so, how hard would the conversion be?

A Edelbrock carb would be a good choice just be sure you get a marine carb .


http://www.edelbrock.com/automotive_new ... rine.shtml


the 1409 would be the one to use

Why would you not have a marine mechanic overhaul the original carb with a carb kit?

We looked into a rebuild. We're a little scared because we've never known of carb. rebuilds to be very successful... And as far as marine goes, there aren't really any competent people in this area that I know of! We looked on the internet to find a place to send it for a rebuild, and it was going to cost nearly as much as a new one. If you know of any reliable places, I'm open to suggestions. Thanks!

I had the original Carter AFB on my 318 rebuilt in 2005 by http://carburetorusa.com/carburetor_usa_042.htm

I was having trouble hitting the rated RPM, and eventually sent out the carb for rebuild after a lot of other troubleshooting. They did the job right and I got 4,000 rpm from the engine for the first time when the re-built carb was re-installed. It's been three seasons and I have no complaints.

The cost was 1/4 to 1/3 the cost of a replacement carb. They offer 2 prices - one for a six month warranty, the other for lifetime. I went for the six month warranty because the warranty says returned Carburetors found to be contaminated with rust, dirt, old gas,or any other types of contamination will automatically void the warranty and a service charge depending on it's condition. That seem fair enough. They are located near Philadelphia. I would do it in the off season because it takes about a week for them to turn it around. If you call they will give you a time estimate. You need to drain absolutely ALL the gas from the carb before you can ship it. If the carrier smells any fuel they won't accept the package.

Good Luck,
Chuck

We really liked your suggestion. We hadn't been to that site before. Thank you so much...this is probably what we'll do.

You may also order a rebuilt carb from most supply companies. i.e. West Marine, Edelbrock, etc. They need your old carb to eliminate the "core" charge. (They rebuild yours). There is little differance between a new vs rebuild carb, other than cost. Amarine carb kit includes all new internal parts of the carb. The only part that is used for the rebuild is the case.

I agree, I am a technican, buy a new one,,,, brand new, its just not worth the headache, trust me

one other thing, I know its alot of money, but they sell an outrageous fuel injection conversion,
they are expensive , but man what a difference, I dont have that on my current boat , but did install a setup on another single engine boat for a friend, and its like having a new engine,
runs perfect and the economy is much much better in the long run

guglielmo6160 wrote:one other thing, I know its alot of money, but they sell an outrageous fuel injection conversion,

Who sells this fuel injection, any links

The Carter AFB and all Holleys are Square Bore carbs - meaning all 4 bores are the same size (1-9/16 to 1-11/16"): 2 primary - for slower speeds up to around 2,500 RPM + 2 Secondaries for WOT operation). They also have 2 float bowls and 2 needles/seats. Great for racing (except off road rough conditions), but not fuel efficient.

The Rochester Quadrajet (Qjet) is a Spread Bore carb - meaning the 2 Primaries bores are relatively small (1-3/8"), and the 2 Secondary bores are very large (2-3/8"). They have 1 float bowl and 1 needle/seat.

When you're idling or running at sower speeds (including planing in most cases), the primaries are in use, and the secondaries are closed. The smaller bore means that, for a given RPM, the air volume taken in (CFM = Cubic Feet per Minute) is the same for both types of carbs. With smaller primary bores (holes), the air velocity on the Qjet is greater, and you have better atomization of your fuel (especially at idle). This translates to better fuel economy, better throttle response and complete fuel burn.

Bottom line - the AFB was great in its day, but the Qjet replaced it for a reason. You can buy Marine Qjets completely rebuilt for $400-500. I replace the AFB in my 26' 454 boat with a Qjet which increased my fuel mileage by 1mpg to around 3.5mpg at 20-24knots. I have one in my old Corvette as well, and it passed smog emission tests after being rebuilt (and goes like hell!) - which an AFB would never have done.

Consider a Qjet!

When I had the gas engines (454's) the flowscan showed one engine using up to 5 GPH more than the other engine.

I founda guy in Miami who SPECIALIZED in MARINE carburetors. (2002)

He determined that he metering rods in one of the quadrajets were not for marine use but for an automobile.

He ebuilt and exchanged the metering rods and reduced that fuel uasage problem.

Try OMAR at JUST CARBURETORS in North Miami BEach.

RWS