2003 5.7 Bravo 3 with a Quadrajet but no choke yet

[dollar7499]

1998 block 5.7 Bravo 3 built to spec of # 4312025PS (the # Crownline gave me from the hull #)

4bbl intake has a flat spot I could drill and tap to hold the choke coil, but some guy said this:
"The problem is that there is no heated air going through the Vortec manifold and head (the port in the head for the exhaust crossover is cast shut). The manifold never reaches a high enough temperature to cause the choke to open and there is no pad or well to attach the stove."
I am a cruiser through and through, and want my wife to be able to start it easily and back the boat off the trailer without a lot of hassle. Does anyone know, or should I just tap it and see?

 

[Bondo]

Ayuh,..... Ya use an Electric choke,.....

Are ya Sure it's a Quadra-jet,..??
They were outa production L o n g before yer boat was built,......

It should have a Merc/ Weber AFB carb,....
If I'm Right,... Edelbrock has the electric choke conversion for their Performer line of carbs, which are Exactly the same as the Merc/ Weber carbs,....

 

[Bondo]

I guess I shoulda read This thread 1st,..... Alot more info,.....

Ignore my post above, 'n get an electric choke conversion for the rochester,...

 

[Scott Danforth]

get the electric choke. intake mounted chokes when way of the dodo bird about 35 years ago.

 

[QBhoy]

Your mechanic is full of mince (as we say here in Scotland) these quadrajet carbs were operating before the vortec heads....at least until they break.
All of my gm v6 and v8 engines all had the choke disconnected and jammed fully off. Just pumped throttle to start from cold and gave them a manual warm up before setting off.

 

[Lou C]

In automotive applications they used both the exhaust crossover heated choke and the electric on later models. Our '75 Olds 5.7 had the exhaust heated style, as does my '88 OMC 4.3. All it took to keep them working right was a yearly cleaning at tune up time. No reason to disconnect, never understood that at all. The Olds went through 15 years of cold cold north east US winters with no starting problems!

 

[dollar7499]

The Quadrajet is on a 1998 Vortec block with a 4bbl intake, and when we took the boat out last week the lake water made the engine so cool that my father in law had to ride in the engine bay with his finger over the carb throat (manual manual choke!) to keep the boat running. (because the choke was wired open) I am installing the electric choke kit this week and checking thermostat operation, even though temp gauge was reading 175*

 

[Lou C]

If your engine runs cool like 140 or so, the exhaust heated choke will take a while to open, in that case the electric is better. In the auto application they open fast, because the normal running temp is 195*. Vortec has to have an electric choke, or manual if you prefer.

 

[dollar7499]

I installed the electric choke conversion kit on my Quadrajet, but when I go to get up on plane, the engine bogs down and backfires through the carb. It idles and drives fine below 1,500 RPM. I think I set the timing 0* and it's supposed to be 8* BTDC. Would that cause this? Are there other things that could cause this?

 

[Bondo]

I think I set the timing 0* and it's supposed to be 8* BTDC. Would that cause this? Are there other things that could cause this?

Ayuh,.... Late timin' yields low power, but backfirin' says it's runnin' Lean,.....

Check the contents of the fuel filter for anything but clean fresh gasoline,....

 

[dollar7499]

I set the timing 8* advanced and it ran like a boss out on the bay, but when I added 20 gallons more of fancy marina gas, it started running bad again, almost left me stranded! Just ordered new fuel filters... hope that's it.

 

[dollar7499]

My problem is fixed!! The new fuel filter is on and the old fuel filter was dumped into a jar and had A LOT of water. Choke is functioning, fuel is clean, timing is correctly advanced... life is good!

 

[DouglasW]

Bondo nailed it.