1984 720 carb questions?

[dustin88]

Hi, I just bought a 84 720 with the 2.4Liter motor. It runs pretty good, Ive never rode in another 720 so I dont know if its a fast as it should be but it runs pretty good above 3000 rpms but its pretty slow below that!

So the previous owner bought a new carb last year, all the paper work says is its a 9468 carb. Anyways the carb only fits on three of the four carb studs. The back right carb stud does not quite line up. I added some rtv and just tightened three of the studs, It runs good but I think it might be leaking still where the stud is missing.

So does anyone know what year carbs fit what? I hate to get a different carb because this one is brand new but I dont know how to make it not leak with only three studs!

I dont care about passing emissions, can I remove and cap all the vacuum lines besides the distributor advance?

One final question, how much power does a weber carb add?
Does a weber 34 really make a noticeable difference in power? If so I may consider buying one and selling my carb.

[captainzeros]

Everything I've heard is that the weber makes a bit more power, but moreover it is way more reliable and will make the truck a nicer beast to drive.

Yes, you can remove and cap everything but the distributor advance.

As far as parts commonality goes I don't know, but personally I wouldn't bother to try and find another hitachi carb off another truck, if I needed a different carb I'd go straight for the weber.

[dustin88]

Well I checked today using carb cleaner and I dont think the carb gasket is leaking.

It starts right up and idles perfect but it runs rough from about 2-3rpms when its cold and it always has a slight hesitation between 2000-3000 rpms

Anyone know what this could be? All the vacuum lines look good.

[flinterman2000]

The hesitation between 2 and 3000 rpm is most likely a timing issue. If there is no pinging then its probably too retarded. Check with a timing light and see if its off.

[PEZi]

The hesitation between 2 and 3000 rpm is most likely a timing issue. If there is no pinging then its probably too retarded. Check with a timing light and see if its off.

^ this

if you can't find a timing light to borrow or don't want to pay for one, try manually advancing the timing and see if it helps

[dustin88]

Well I dont have a timing light but it was set all the way advanced, I tried retarding it and it made it worse.So I dont know!

One more thing, when are the secondaries supposed to open up? On mine they open slightly open when I floor it. Is there an adjustment for this? To me the truck feels like is not getting anough gas.

[PEZi]

it opens at 3,000 rpm or full throttle

[breadbox]

Have you changed the fuel filter?

[dustin88]

Well I sold the truck last night, Im going to stick with fuel injected vehicles!

[MetalFab]

Haha! good idea. I have plans in the wings for an efi v6 as I have never been happy with the lack of power and horrible MPG these motors make. I do hope that changes drastically with a weber. For one, you can actually adjust a weber, instead of the set factory specs on the carters. I did a vac delete and now my motors idling all over the rpm band. 700-3k and everywhere inbetween depending on altitude, temp, and unknown other reasons. I've tried unplugging the wiring harness to the carb, but that makes it run even worse.

[dustin88]

Well I did like the truck but I really had no need for it and I bought it to tow jetskis and I dont think it had the power to do what I needed it to!