1985 nissan 720 rwd california daily.

[DIY 1985]

The earlier years have three hose canisters that can be had new. My DGEV has no float bowl vent, so I only need three anyway.

 

Make sure your EGR is closed, it is akin to a vacuum leak. I just replied mine because iron casting was rusted into flakes.

 

Check the studs that hold the base of the carb to the intake; I wrapped mine with tons of Teflon tape to make them snug, others used locktite. This is common.

 

I currently am running a DGV on a stock pump, unmodified, fine. Check your jets for obstruction, and your float level. Make a note of which jet came from where for future tuning.

 

Course tuning can be done with your ears and 'reading spark plugs.' It should be driveable, but an A/F guage will be for precision.

[DIY 1985]

Sorry, replaced, not, "replied."

[datzenmike]

I would put the original feed and return line back on and skip the regulator for now.  A new Weber should handle 4PSI. If higher than this place regulator between pump and carb but keet that stock return line hook up.

[Crashtd420]

I would put the original feed and return line back on and skip the regulator for now. A new Weber should handle 4PSI. If higher than this place regulator between pump and carb but keet that stock return line hook up.

The carter pump he is using is the same I have and was putting out about 6 psi without a regulator..

you could even skip the return line as a test and just feed the carb.... those pumps internally circulate so they are good on a non return system, but I feel they need the regulator....

[Toxicrain]

The earlier years have three hose canisters that can be had new. My DGEV has no float bowl vent, so I only need three anyway.

 

Make sure your EGR is closed, it is akin to a vacuum leak. I just replied mine because iron casting was rusted into flakes.

 

Check the studs that hold the base of the carb to the intake; I wrapped mine with tons of Teflon tape to make them snug, others used locktite. This is common.

 

I currently am running a DGV on a stock pump, unmodified, fine. Check your jets for obstruction, and your float level. Make a note of which jet came from where for future tuning.

 

Course tuning can be done with your ears and 'reading spark plugs.' It should be driveable, but an A/F guage will be for precision.

 

I will definately check the studs to see if they came loose after driving and idk what the guy who put my carb in used to snug the threads even if he used anything.. I have been carb cleaning the jets every time I open up the carb to see if the fuel bowl is full. I will check into the egr because its still there until I can fab up a plate to remove it correctly.. I will try to get some pictures of the vaccum ports I have plugged and what is left on the intake.

 

I would put the original feed and return line back on and skip the regulator for now.  A new Weber should handle 4PSI. If higher than this place regulator between pump and carb but keet that stock return line hook up.

 

I just didn't see the point in all the unnecessary bends but I guess they did them for a reason.. if I can find it in my bed full of crap I will reinstall it and just trial and error the situation..

 

 

 

Im only 17 and have had only the experience with my truck in carburetors and what ive learned from here and what others have said about them so whatever information and tips I can get ill take :D

[Toxicrain]

The carter pump he is using is the same I have and was putting out about 6 psi without a regulator..

you could even skip the return line as a test and just feed the carb.... those pumps internally circulate so they are good on a non return system, but I feel they need the regulator....

I have tried it with the rubber line I ran from the pump to the carb and the results were I think was air in the line was that problem and I got no fuel to the bowl.

 

Some people have had luck with just the pump and no regulator but I'm not trying to get 10mpg and the pump does around 7.5psi.

[DIY 1985]

Toxicrain, I'm seeing what looks like a (red-brown) one-way-vacuum-check-valve coming off of the EGR in a photo you posted earlier, I could be totally wrong.  The EGR's top connection actuates its diaphragm-valve, and by simply disconnecting it makes the kind of delete that was instructed for the conversion kit of my DGV.  You can also sandwich a bit of sheet metal between the EGR and the manifold, the EGR holds the sheet metal seal tight and flat.  Some people go this route because they can fool an emissions inspector who can basically only see just gasket material between the EGR and manifold.  Drilling into sheet metal is cleaner if you do it in a sandwich between wood or scrap material.  Getting the EGR off is a pain, take off the like 5/16" stainless plumbing from its base because it may get in the way of a crescent wrench, use a medium size adjustable pliers as well because there is not enough space to walk the hex nut far enough to grab its next side.  After you break the valve side just free, go on to just loosening it up the manifold.  It took me a while.  I imagine that you might also remove the EGR studs in the manifold with a double-nut method, but I didn't on mine.

 

Careful opening the top of the carb, you can distort the float by knocking it against the wall if it doesn't come up fairly straight.  You should have 18mm between the top of the float bowl and the top of the gasket https://www.youtube.com/watch?v=fhYSo6u-Jm0

 

The intake manifold studs have a torque setting in a stock set-up, so be careful not to over-tighten.  Stubby wrenches were needed because of the rocker-arm cover.  Also, two allen screws are hidden (counter-bored) in the adapter plate, you can't see them with the carb attached, but they were not as loosey-goosey as the two studs that go into the manifold (on the choke side of the carb).  Once again, I chose Teflon; it fills the space between the threads.

[datzenmike]

Well if visually inspected the Weber alone will fail you.

 

The Weber won't have a ported EGR anyway and without it no EGR is possible and another reason why it won't pass a visual or an emission test.

[Toxicrain]

 

Does the "one way" part of the check valve make a difference? Asking this because i have one similar also when I put the new tank in.

[Toxicrain]

Well if visually inspected the Weber alone will fail you.

 

The Weber won't have a ported EGR anyway and without it no EGR is possible and another reason why it won't pass a visual or an emission test.

If I wanted to attempt to pass visual, cutting the stock intake induct / filter and lay it on top would be an option

 

For the egr I was planning on using the studs and just threadlocker nuts/washers the plate in place.

 

I get tephlon tape by the roll for .30c so ive been using that to seal all my threads and so far success.

[datzenmike]

When is your next emissions test? less than two years? Everything after '75? must be original emissions compliant from carb to non vented gas cap. Nothing altered or substituted.

 

It's a valve that prevents gas expulsion if there is a roll over.

[DIY 1985]

The hose on the top of the EGR is supposed to have two-way action.  My suspicion is that the EGR is in the open position and if you simply remove the top hose leading to the one-way check valve, you will get the carb tuned to a drive-able state.  The hose from the base of the EGR is exhaust pressure leading to the Back Pressure Transducer.  Cap it, or leave that lower hose in place; you don't want exhaust gas in your engine bay.

 

In a stock condition, ported (throttle-dependent) vacuum should open the EGR valve when the Thermal Vacuum Valve (located behind the thermostat) has reached temperature and its air bleed is closed.  No exhaust gas is recirculated when the vehicle is at idle (because it is connected to ported vacuum), or, when it is cold (because of the air bleed).  The Back Pressure Transducer is a second vacuum air-bleed connected to the EGR line that will effectively close the EGR when the motor is having trouble producing enough exhaust pressure.  Like the spark advance on the distributor, Wide Open Throttle does not activate the EGR vacuum either, because it is a 'ported' source and there isn't a Venturi effect in the throttle body.

 

You can check that the EGR opens and closes by sucking air through a 3/16" vacuum line attached to the top of the EGR.  You will hear it open and close.  And at idle, you can stall, or stutter, the motor by activating it.  For trouble shooting purposes, just make sure the EGR is closed, or disconnect the upper line.

 

Until the weather improves, I am running a DGV that only has one ported vacuum source.  However, I'm eventually going to install a DGEV, like the one on the Pierce Manifolds YouTube video, that has an EGR port, a ported spark advance, and a manifold vacuum source (which may serve to activate the original Anti-Backfire Valve).  My opinion is that spark advance and EGR are integrally designed systems, other people don't run EGR.

 

Did anyone mention to check your choke butterfly position?  After the motor turns over, it should partially open, then fully open.  It is adjustable by means of rotating it after you partially loosen the three screws on its housing.  There is an external screw with spring that adjusts idle speed for warm-up conditions on the DGEV.

[datzenmike]

The 32/36 doesn't have an EGR port so the EGR won't be activated. Ever.

 

Get a stock carb from another '85 and get everything working again.

[Toxicrain]

When is your next emissions test? less than two years? Everything after '75? must be original emissions compliant from carb to non vented gas cap. Nothing altered or substituted.

 

It's a valve that prevents gas expulsion if there is a roll over.

Yea i got the last owner to pass smog on it before i bought it so im good until aug 2019. It was stock and i kept the stock hitachi but it needs a rebuild and im not sure if the guy gave me all the pieces from the swap if i wanted to put it back together.

 

I will also just cap those hoses instead of keeping them in a circulation although i think the egr is deadweight with the weber installed because there is no port for egr on it

[DIY 1985]

(3:20)  https://www.youtube.com/watch?v=A44-xG3pKlY

 

Mike, so the ports he is talking about are wrong?  I hope that they let me send them back the DVD and carburetor.  It says 32 36 on the aluminum casting.

[datzenmike]

Would have been way simpler/cheaper to rebuild the stock carb.... and you're going to have to in a year's time anyway.

 

 

I've never seen an EGR port on a weber, maybe some newer ones have it but how can it know the needs of an '85 720 with a Z24???? I wouldn't run it and anyway. It has to run off the bottom of the throttle plate just like the vacuum advance and be off at idle. You can't run ERG at idle. It won't idle and not needed anyway. Again it won't pass a visual inspection even if by some miracle it could pass the emissions.

 

Don't remove the EGR! It's not doing anything and doing no harm. You're going to have to put it all back on next year. Save yourself the headache. If planning to sell it to avoid putting everything back together the new owner will give you less for it. A smog-able truck is worth much more than one missing parts to get it on the road.

 

 

 

You do need the ported vacuum advance for the distributor.

[DIY 1985]

The same could be said about spark advance on the Weber.  Distributor timing needs to be refereed by a Vacuum Control Valve; three connections should be made to carburetor vacuum, two of which are restricted by an orifice, according to the FSM.

[Toxicrain]

I'm going to leave it like this and forget about having to put it all back on. Never got rid of the stock one and keeping the vacuum hoses and diagrams just in case I do have to put it back on.

Was looking into getting a welder soon and just weld 3 cats on and hope for the best if i needed to.

Got the holley fpr yesterday and got the wrong fittings and wasnt gonna pay $4 a fitting when i can get them $1 from my work. Hopefully ill find some time tomorrow because i gotta pull out the rear end of my parts datsun.

[Toxicrain]

Also put the stock return/main metal line that ran up from the rail. Hopefully i put it on right i noticed one line was bigger than the other so i just corresponded and hooked big-big small-small.i did notice that restriction mike was talking about in the return part when i was blowing air through the line before i put it in to make sure it wasnt blocked

[Charlie69]

Big is fuel supply small is fuel return.

[datzenmike]

Actually I think it's the other way round Charlie. I know, it seems wrong, but I'm pretty sure this is the case.

[Toxicrain]

 

 

I was able to get her runnin after i installed the holley fpr and the psi sits at a solid 3.2 and was able to drive her to town and wash and get gas. Only problem is throttle hesitation and the muffler was shot so its removed so its loud.. Alternator isnt charging battery even though i just replaced both of them.

 

Volts before is 12.40 and when idling its at 12.23 took alternator to autozone and they said it was good.

 

Put it back in and now i dont get any power to ignition or stater. No lights come up on dash other than the clock. Lately my rpm gauge has been working only half the time and ill usually just tap the dash and it works again

[datzenmike]

Fusible links. Check them after checking the battery cables and posts are clean and tight.

[Toxicrain]

When i put it in the alternator the first time i think i wired power to ground and was getting high arc when trying to put the power cable on and i melted the link once and replaced it with the one out of my 80' parts truck. I just cut new cable and put new post clamps on. Checked all my fuses and they looked good.

 

I cant really follow the wire that goes to the alt from batter because its in a harness most of the time but the ends look good so im not sure where it could have gone bad.

I found a pic of when i put it in the first time and found my mistake of the power going to ground.. and so I moved the ground to the block and put yellow wire to bat. I know its getting power because i used the multimeter on the post and at the alt.

[datzenmike]

There are 3 fusible links on the 720. One goes to the ignition switch then to the fuse box for things that are shut off with the key like wipers, heater, ignition. One to the fuse box for head lights. One to the fuse box for things not turned off like horn, brake lights, interior lamp.