How much RTV is needed...

[HotRodPC]

It's sad, carbs in general are getting hard to find now.

Have any large bore 2bbl Rochesters? I don't recall the model number, but they were used in the '69-'70 full sized Chevy cars. Earlier years had a smaller bore and the fuel inlet in a different spot.

I couldn't tell where, but I'm 90% certain I still have one of the large bore 2bbl Rochester good core. Came off a mid 70's El Co IIRC. I know I no longer had the small bore 2bbl off the mid to late 60's. Mine was brand new reman in the box I exchanged at Pep Boys many years ago after I upgraded to a Holly Intake and Carb but kept the New Reman for many years. Sold it on eBay a little over a year ago or so for $125.

 

[spanky55amg]

Well. Spent the afternoon renewing the Holley. Got it on the truck and about the time it heated up, the secondary boosters were full on dripping and flooding. Pulled the fuel bowl and found trash in it. Cleaned it out again. And set the float a touch lower. Drove to the gas station and right before I got there, it died. Coasted in. Found the primaries now's leaking. Got on to it with the business side of a flash light and no more problems. F these non adjustable float needles.

Fingers crossed this all works out tomorrow.

 

[spanky55amg]

And sorry, didn't get many pics of summit. I was like a kid in a candy store.

 

[spanky55amg]

10 fish stick question. I read that the 4165 has reverse idle screws or some bs, is this true or false?

I have the idle screws about 1.5 turns out. There are only idle screws on the primary metering block, none on the secondary.

Also, this thing dies under heavy breaking. I have been reading high float level. It does seem to run a little rich and I was thinking float level before the dying.

Lastly, I didnt set up the choke yet. Eh, its a vacuum only divorced choke, how good can it be. (some sarcasm there) Anyways, when cold and I get into the throttle a little, I can hear it blow off through the carb. I almost though power valve, but I removed the 8.5 and put in a 6.5. So could that be from a high float, or does that sound like PV?

 

[74 Shortbed]

Vacuum holds the PV closed, so the lower the number the longer it takes to open. But sounds like the choke needs adjustment, and maybe drill the shooters one size bigger if you're getting hesitation, not PV.. And BTW, only do "ONE change at a time"..

 

[Jrgunn5150]

10 fish stick question. I read that the 4165 has reverse idle screws or some bs, is this true or false?

I have the idle screws about 1.5 turns out. There are only idle screws on the primary metering block, none on the secondary.

Also, this thing dies under heavy breaking. I have been reading high float level. It does seem to run a little rich and I was thinking float level before the dying.

Lastly, I didnt set up the choke yet. Eh, its a vacuum only divorced choke, how good can it be. (some sarcasm there) Anyways, when cold and I get into the throttle a little, I can hear it blow off through the carb. I almost though power valve, but I removed the 8.5 and put in a 6.5. So could that be from a high float, or does that sound like PV?

Never heard of reverse screws, but who knows?

If it's rich at 1.5 turns, turn them in and see how that goes.

How did you set the float level?

Don't monkey with everything all at once or you'll get all effed up and never know what helped and what hindered. I start with my idle, then my mixture, then get into real tuning. Do you have a vac gauge? You really should, or at least a tach, otherwise you're just pissing into the wind.

 

[74 Shortbed]

Never heard of reverse screws, but who knows?

Yep, vacuum secondary 4165's have reverse mixture screws, and they are different as you don't adjust fuel you adjust air bleed so they will run wether they are all the way in or out, they are sensitive though and transfer slot is critical also, they are a very good carb just have to learn how to tune them, they are different than a 4150/4160..

 

[spanky55amg]

ok... so after working on it some more.

first, I have adjusted the floats, which were correct before the renew, but after were too high. They always leaked out of the boosters, both primary and secondary. This both took two adjustments after it was put back together... stupid "non" adjustable floats. (you have to pull the float bowls and bend the float hanger.)

I put on new hoses for the dizzy and whatever the one thing is on the passenger firewall and I guess they really needed to be replaced as the carb started to run better.

this is a mechanical secondary. and after working on it some, when I loosened the idle mixture screws it would backfire through the carb. So lean back fire, correct? So then tighter means more rich... right? The needles are only 1/2 a turn out.

Also, what I thought was a choke (like an idiot) isnt a choke, its just the choke pull off. This carb does NOT have a choke on it. These cold mornings are fantastic without a choke.

which brings me to my last question. The carb had a 8.5 PV in it. I thought while rebuilding it was running rich. With the POS rebuilt q-jet, I was only getting 10 in of vacuum. So I thought that I would put the 6.5 in it. Now, when I roll into the throttle specifically off idle or off cruise, it "coughs"/backfires through the carb. Still thinking PV I was researching this morning and it seems like its still a lean backfire. The measurement of vaccum to determine the PV; Is that done in gear or in park? I have 18/19 in of vacuum in park, which should mean the 8.5 or I have 14 in drive which should be the 6.5. Just going by the "cough" and hesitation, Im guessing I should throw the 8.5 in it.

 

[74 Shortbed]

What size squirters do you have???, the PV is for part throttle acceleration at cruise, as you push on the throttle vacuum drops and the PV opens when it drops to it's rating, when you whack the throttle the accelerator pump feeds it fuel, squirter hole size determines the volume of fuel to cover the hole, the cam determines the duration of the shot..

 

[spanky55amg]

What size squirters do you have???, the PV is for part throttle acceleration at cruise, as you push on the throttle vacuum drops and the PV opens when it drops to it's rating, when you whack the throttle the accelerator pump feeds it fuel, squirter hole size determines the volume of fuel to cover the hole, the cam determines the duration of the shot..

Good f'n question? I dont know. Haha. Im just trying to get this to run like it kind of did before I touched it but without it leaking. I should have just replaced the bowl gasket and needle and called it a day until my q-jet comes back. But now Im getting too deep into something I didnt think I was even digging in.

 

[74 Shortbed]

Good f'n question? I dont know. Haha. Im just trying to get this to run like it kind of did before I touched it but without it leaking. I should have just replaced the bowl gasket and needle and called it a day until my q-jet comes back. But now Im getting too deep into something I didnt think I was even digging in.

Look at it this way, if you'd have just replace the gaskets you wouldn't be getting all this edumacation, lol..

 

[spanky55amg]

I also questioned if the accelerator pump was adjusted correctly, but the backfire through the carb happens at cruise, which would me that there was already some pressure on the AP. Although, that could still be the issue but Im pretty sure thats adjusted correctly. I think I just keep going back to putting in the 8.5 PV for now.

 

[spanky55amg]

Look at it this way, if you'd have just replace the gaskets you wouldn't be getting all this edumacation, lol..

Very true. But its something I didnt want to learn. But I guess Im learning more about Holley's than I ever though I needed or wanted to know. This truck shouldnt have this Holley as a DD or cruiser. I dont know how some of you'll do it. Its a pain in the ass. I want my q-jet back. haha. (with the float adjusted correctly and down a couple of metering rod sizes).

 

[74 Shortbed]

I also questioned if the accelerator pump was adjusted correctly, but the backfire through the carb happens at cruise, which would me that there was already some pressure on the AP. Although, that could still be the issue but Im pretty sure thats adjusted correctly. I think I just keep going back to putting in the 8.5 PV for now.

The accelerator pump arm has to move with the very slightest movement of the throttle, it has to pump fuel as the throttle is opening or you'll get a stumble or pop out the top. You're going the wrong way on the PV, if you're not getting enough fuel it needs to open earlier, take a vacuum reading at idle and put the closest PV to the vacuum reading, just enough to hold it closed and try it. But normally the PV won't make it pop on cruise, if it's not opening quick enough(not enough fuel) when you accelerate it'll just lay down until it opens then it'll take off again, if it opens to quick(too much fuel)it'll be lazy until it cleans up.

 

[74 Shortbed]

Very true. But its something I didnt want to learn. But I guess Im learning more about Holley's than I ever though I needed or wanted to know. This truck shouldnt have this Holley as a DD or cruiser. I dont know how some of you'll do it. Its a pain in the ass. I want my q-jet back. haha. (with the float adjusted correctly and down a couple of metering rod sizes).

Holleys are about as simple as you can get, lol, the only one simpler that I can remember is the Autolite 4100, that is a total no brainer, lol.. But in reality it's all what you get used to..