scoop question!

[460 jus getn it]

ok i just got back from the lake. i had to turn my scoop backwards for my boat to run right. if i had it normal it wants to lay down at 4400rpm. has anyone ever had this happen before and why is this happening?????????????

[Floored]

could be leaning out the carb with extra air being rammed in. check plugs. check fuel pressure also, it will pressurize the vent tubes and restrict fuel flow into carb at speed.

[PonyFiveO]

I am glad this question was posted. :D I was just getting ready to post the question..."Why do some people run their scoops forward while others run theirs backwards??" I once heard someone say that by having it backwards, it gives it a "cowl induction" effect. I also heard, "keeps water out of the carb", and "keeps crap out of the carb while towing to the lake."
What are everyones experiences and expert opinions on this? Thanks! :shift:

[victorfb]

an old trick is to cut 2 holes (1 1/4" - 1 1/2") on the bottom side in the rear of the scoop. this will allow a relief but still give the benefit of a slight ram air flow.
running a flame arrester in the scoop may help aswell.

[Squirtin Thunder]

460, Tyro,
What carb is that, that you are running ???
http://www2.***boat.com/image_center/data/520/1570DSCF0026-med.JPG

[460 jus getn it]

460, Tyro,
What carb is that, that you are running ???
http://www2.***boat.com/image_center/data/520/1570DSCF0026-med.JPG
its a holley 800cfm double pumper.ill get the number later. its weird its like the motor doesnt like the amount of air that being taken in.

[Squirtin Thunder]

Is that one of those silver emision types that the top comes off ???

[460 jus getn it]

Is that one of those silver emision types that the top comes off ???
how did u know that. yes it is, give my the low down on this carb please

[BrendellaJet]

Looks like a holley 4810/4811 marine carb...

[1978 Rogers]

I am glad this question was posted. :D I was just getting ready to post the question..."Why do some people run their scoops forward while others run theirs backwards??" I once heard someone say that by having it backwards, it gives it a "cowl induction" effect. I also heard, "keeps water out of the carb", and "keeps crap out of the carb while towing to the lake."
What are everyones experiences and expert opinions on this? Thanks! :shift:
Don't you have a scoop to act like a ram, to force more air into the engine? Won't you create a vacuum buy putting it on backwards?

[460 jus getn it]

Those are 4010/4011's. Jim that is the one I just rebuilt for the daycruiser last year. One of them is a spread bore and the other is a square bore. If they work they work fine ,if they dont then they dont- and it needs to be tossed. I hate mine, want another one? fresh rebuilt but works like crap... Free
mine is a spread bore. is there any advantages or disadvantages to this carb. if so what do suggest for a replacemant?

[460 jus getn it]

There was several claims to their fame, one being no gaskets below the fuel level. The other was a inexpensive Holley replacement for the Q jet. Some one on ebay sells rebuilts of these for 150.00 and they have a list of the advantages. None of which I see as a good reason to have one. They are prone to power valve burn out. It takes a very small backfire and there blown. Of course if your motor is tuned and working right then it's not an issue but if you do get a tiny backfire, your hosed. If it works good keep it on there. If not and you have to have a spread bore and dont want an adaptor, Holley has a spread bore 6210? (spendy tho )not sure of the number anymore but summit lists it. Or go the "Jet" brand rebuilt Q-jet performance carb also at Summit . Personly I dont recomend any of those but if you need to stick with that type then those are your options and they will work just fine. Or go with an adaptor or new intake. Hope that helps..
ok i dont have to have this on my boat. i have a adapter right now. i just picked the carb up real cheep of course. i havent had a problem yet but will look to get a replacement..................

[victorfb]

if you can get passed everyone saying that Q-jet is a pile of crap you can replace it with one. the Q-jet can be a damn fine carb. i have a rebuilt one thats been sitting for a while if you want to try it. if i remember correctly they are 800 cfm. on a heavy boat they work well as the primarys are small for the take off torque, then the secondarys are huge.

[Squirtin Thunder]

Those are 4010/4011's. Jim that is the one I just rebuilt for the daycruiser last year. One of them is a spread bore and the other is a square bore. If they work they work fine ,if they dont then they dont- and it needs to be tossed. I hate mine, want another one? fresh rebuilt but works like crap... Free
Personaly I dont think they are a pile as well. I am revealing my age but that was all I had as a kid and there are a few cool tricks that make those work very well. If ya got one that works use it for sure..
So you just feel that way about the Holley want-a-be copies right ???

[QuickJet]

I had the same problem with my 850 Holley. I put the flame arrestor back on and the prob went away.