My Desmog Thread (7 Viewers)

[Miloslavich]

Check em' out

Jim,

I finished up the vac line routing, and i believe i have it all sorted,

however there are 2 lines i am not sure about..


1:

This line- which i think may be related to some sort of cruise control system which was installed on my Truck,

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2: This line, which comes from the firewall on the passenger side , and i believe was associated with the Charcol cannister system -

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here are a couple pics of general vac line routing - if you see anything that doesnt look right chime in

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on this one, i wasnt sure where the large tube that comes from the Carb base goes, (the large j-shaped pipe that comes up from the mounting plate) - you can see it behind the brake booster. - is that correct?

Thanks Jim.

 

[fliphkd778]

Looks good, 1) I would agree that looks like a line to the aftermarket cruiser 2) I am guessing goes to the vacuum control valve clamped under the air cleaner housing above the dizzy

 

[FJ40Jim]

Jim,

I finished up the vac line routing, and i believe i have it all sorted,

however there are 2 lines i am not sure about..


1:

This line- which i think may be related to some sort of cruise control system which was installed on my Truck,

------------------


2: This line, which comes from the firewall on the passenger side , and i believe was associated with the Charcol cannister system -

----------


here are a couple pics of general vac line routing - if you see anything that doesnt look right chime in

---------------


on this one, i wasnt sure where the large tube that comes from the Carb base goes, (the large j-shaped pipe that comes up from the mounting plate) - you can see it behind the brake booster. - is that correct?

Thanks Jim.

Pic#1, the vac hose for the AM cruise probably goes to a source of manifold vacuum.

#2, hose comes from filter in glovebox, goes to VCV for dissy cap vent system.

#3 Looks good. Excellent re-usage of EGRVM bracket for HACV.

#4 A part is missing. The hose from the manifold and the hose from the charcoal canister should both be connected to a VCV.

Do not connect it the way it is becuase it is applying full manifold vacuum to the canister and ultimately the fuel tank. There is a very real concern that the tank could collapse, or there will be so much vacuum in the tank, the fuel pump will not be able to pull fuel out & the engine will stall.

 

[Miloslavich]

Ok Jim, searched around and i think i figured it out. Gonna put a VCV in that line. question is: the VCV that is stock on the truck has 2 additional 3mm Vac line ports on it. since i am BVSV-less, i am going to Cap that port, and the other port. so basically the only lines to and from the VCV will be the 2 6mm lines. Or, do i need additional 3mm vac supplied to that valve?

is that good to go?

 

[Miloslavich]

Found TDC, installed the dizz- new plugs and wires, and went from there -

With that setup, i got the rig running! - set the timing shes good to go-



so i have 3 remaining questions for ya Jim-

1. do those VCV's need additional vacuum other than the 6mm's going in and out of them (the 3mm's are capped)

2. - My friend who will not be named tweaked all the settings on the carb - was wondering if you could tell me what the ideal settings are for the screws - how many turns out ?

3. Is there an optimal setting for the timing i should shoot for - being at 6000 ft. elevation?









thank you Jim, your advice is much appreciated.

 

[FJ40Jim]

1. do those VCV's need additional vacuum other than the 6mm's going in and out of them (the 3mm's are capped)

Yes, one VCV fitting needs to get vacuum through a BVSV. other small fitting is just a vent.

2. - My friend who will not be named tweaked all the settings on the carb - was wondering if you could tell me what the ideal settings are for the screws - how many turns out ?

WTF, why would somebody twiddle screws on a new carb??

The screws are all adjusted to running specs.
Base idle speed is adjusted to 650RPM or user preference.

Idle mix screw is adjusted for peak idle RPM, plus another 90* CCW,

Hi-idle is adjusted to 1800-2000 w/ engine warm and choke pulled to peak RPM

AC idle up is adjusted for 2-300RPm above base idle w/ compressor on.

3. Is there an optimal setting for the timing i should shoot for - being at 6000 ft. elevation?

With all vacuum disconnected from advancers, start at 10*BTDC, at or below 700RPM. If engine doesn't rattle, add 4 degrees and drive some more. If engine doesn't rattle, add 4* and drive some more. If engine rattles, remove 4* until rattle goes away.

 

[Miloslavich]

thanks Jim, this is the 1st carbed vehicle ive worked on, had the pleasure of dealing with fuel injection in all of my other vehicles.

because i had never set the timing on a rig like this before, had a couple friends help out, however, what happened was the dizz was put in a couple teeth off the 1st go-round, so when we couldnt find 7* advance the 1st time, that friend started turnin screws on the carb,.. i really didnt know any better, i thought that was possibly needed to find 7* advance with the timing light-

i came to find out with some more research that the dizz wasnt right to start with, so when i re installed it this am, 7* advance was right in the window with the light the 1st time.

now i gotta go through the process of re-setting all the carb screws. im pissed i even let that fool touch my truck. im pissed i wish i could just send you my carb again just to have you adjust it lol!! never seen you say "WTF" on the forums before! its as if someone ruined your art work by messsing with my carb !

its a learning process for me, Luckly folks like you are willing to help give advice to us rookies.

thanks for your help.

 

[bigDcruiser]

is there an alternative to the BVSV in the thermostat housing? top was broken while trying to remove it and the bottom one broke when being moved to the top position. these damn things are brittle. what effect will i get by capping both ports? is there another location i can connect the front vacuum port on the carb that is supposed to go to the BVSV?

 

[FJ40Jim]

You can try connecting vac directly from carb base to the VCV, see how it drives, especially when cold. The BVSV prevents the VCV from connecting evap to engine before engine is warmed up. I suspect that bypassing BVSV altogether will allow too much evap into the intake manifold, which will make a cold, stumbly engine more stumbly.

Try it and post your findings.

 

[dbleon]

is there an alternative to the BVSV in the thermostat housing? top was broken while trying to remove it and the bottom one broke when being moved to the top position. these damn things are brittle. what effect will i get by capping both ports? is there another location i can connect the front vacuum port on the carb that is supposed to go to the BVSV?

Question... Do you have to drain the coolant before removing the BVSV's???

Thanks

 

[bigDcruiser]

i only lost a few ounces of coolant when i pulled the BVSV's. not sure that my system is totally full but they're pretty high on the cooling system.

thanks for the quick response jim. since it's warming here in texas i may be able to get around for a bit until i can get another BVSV. i need to get out of the rental, i'm going on four weeks and it's getting expensive.

 

[Miloslavich]

Im BVSV'less and just hooked manifold vacuum to the VCV's to provide vac to them. We'll see how it responds when it gets cold out this weekend. I'll post up my findings.

Jim- got the carb sorted out . thanks for your help.

 

[bigDcruiser]

well she's up and running again for the first time in over 3 weeks. started with no issues and idled at about 650 for 10 mins but has now climbed to about 1050. smoking like a chimney from all the degreaser, ect. that's gotten on the manifold. got a backfire when i throttled up but i'm assuming that was due to the fuel cut switch not being connected yet. i recycled old vac lines until i get more and don't have a piece long enough to connect it yet. still need to re-read the thread and insure things are routed properly. i have developed an annoying squeal now when i apply throttle. any thoughts on that?

edit: i actually do have the fuel cut attached. it's the a/c idle up that doesn't have vac connected but i tested and it seemed to increase with the a/c on.

 

[FJ40Jim]

Im BVSV'less and just hooked manifold vacuum to the VCV's to provide vac to them. We'll see how it responds when it gets cold out this weekend. I'll post up my findings.

Jim- got the carb sorted out . thanks for your help.

If the VCV for evap is connected to manifold vac, then the engine will be sucking on the fuel tank whenever the engine is running. Better to connect as stock, to a ported vac source, so that evap VCV is switched off when idling.

OTOH, the dissy ventilation VCV does get manifold vacuum, because it is not a vac leak into the intake manifold.

You're welcome.

 

[Miloslavich]

Jim, because i am without BVSV's, what do you recomend as a source of ported vac for the VCV? perhaps the port on the carb?

 

[FJ40Jim]

Yes, the correct routing is <ported carb vac-BVSV-VCV-evap>.

Eliminate the BVSV, go direct from ported vac to the VCV, see if it stumbles badly when cold.

It will be fine when warm, because the BVSV is outta the picture when warm anyway.

 

[dbleon]

Yes, the correct routing is <ported carb vac-BVSV-VCV-evap>.

Eliminate the BVSV, go direct from ported vac to the VCV, see if it stumbles badly when cold.

It will be fine when warm, because the BVSV is outta the picture when warm anyway.

Does it go to pass, or drivers side VCV?

Thanks

 

[FJ40Jim]

Drivers side is the VCV for evap.

The VCV on pass side under air cleaner is for dissy cap ventilation.

 

[dbleon]

Drivers side is the VCV for evap.

The VCV on pass side under air cleaner is for dissy cap ventilation.

Thank you

 

[Miloslavich]

if you were to go without VCV on the dizz cap ventilation, just hooked the hoses up what would be the potential negatives to that?