• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

V6 vacumn lines... bare minimum?

1986xj

NAXJA Forum User
Sorry for posting both forum's but nothing helpfull yet over on mod tech and want to have it all done tommorow....
Dumped the rochester for a Weber and need to make sure I keep what is absolutely needed as far as vacumn and run the right type of vacumn to those items.
Here's what I kept.... variable vac from front of carb to distributor and EGR, manifold vac to air injector control valve and tin resivoir canisters on PS fender. Is this correct? Is there any need for vac to the canister (charcol?) up near the rad. on the DS? Just running the bowl vent to it.
Thanks,
Mike B.
86, 3.4 w/2.8 intake & junk, ax5, 207, disco 30
BTW... not woried about disco lines, they're busted up anyways and I have a posi-lok cable setup to put in.
 
I do not have the V6, but I have done a similar conversion to my 2.5 lt engine.

If memory serves me right (I am at the office right now), the only pipes I've left are the one going to the distributor, and the one going to the vacuum canisters. I've dumped the charcoal thing and the EGR, so I am not sure about them. Finally, if I remember correctly, there is a pipe going to the brake booster.

If you want more details, e-mail me ([email protected]) and I'll check later on and get back to you.

Rgds and Merry Christmas
 
Did you just not run vac to the EGR or did you remove it and use a block off plate? Was wondering what the effects of leaving it there without it being operational would be if any.... was gonna experiment a little with it this weekend. Did brakes and 1 unit bearing on friday so I didn't get to fool with anything else yet..
Thanks,
Mike B.
 
1986xj said:
Did you just not run vac to the EGR or did you remove it and use a block off plate? Was wondering what the effects of leaving it there without it being operational would be if any.... was gonna experiment a little with it this weekend. Did brakes and 1 unit bearing on friday so I didn't get to fool with anything else yet..
Thanks,
Mike B.

I just didn't run vacuum to the EGR, you do not have to remove it. No vacuum no operation.

With all other emission control devices removed, and only the catalytic converter, the XJ still passes the (local) DMV checks, but for non-catalytic cars (it was imported here before the catalytic converters became mandatory, so it is OK as it passes the pre-catalyst levels).

Rgds
 
Set timing today, and it cleared up the backfire. When I pull and plug the vac to the EGR I get a slight pop or 2 through the exaust so I left it hooked up. It is running much better now with the timing set at 12* but is still seems to have a slight miss at rpms under 2,300 or so, might try some new plug wires tommorow and check to make sure plugs were properly gapped. I didn't figure out where to mount the fuel pressure regulator & gauge yet, would running a little extra pressure (I think the GM 3.4 conversion elec. pump is about 5-6 psi) cause the idle and lower rpm range to be a tad rough?
Still need to know about the correct vac to the air pump control valve.... seems that it is allowing exaust to flow the wrong way... or is there a check valve that might be bad? Might still just yank the whole air pump thing if I have to, just thought it might be nice to have it function since I had to put a brand new air pump on to pass the inspection to get tags.
Mike B.
 
Dip sh!t had #4 & #6 plug wires switched..... guess it's time to go back to doing all my own work again Grrrrrr. Runs like a raped ape now, with the 4.10 gearing and the little ole 225's it keeps ya pretty busy shifting gears it revs up so quick...
The idle is still a tad lumpy, might be the 4 & 6 plugs are fouled though from that fiasco..... plan to pull them all and check gap since thats about the only thing I haven't checked to see if they screwed up.
The GM electric fuel pump for the 3.4 swap was putting out 5 psi, put a regulator and gauge on and backed it off to 3 psi and was able to get the carb dialed in much better. Tech at weber said 2-3 psi should work best.
Well enough of my 1 man disscussion for now :wave: at least maybe someday someone may find my ramblings of use in the archives.
Mike B.
 
1986xj said:
Dip sh!t had #4 & #6 plug wires switched......
Well enough of my 1 man disscussion for now :wave: at least maybe someday someone may find my ramblings of use in the archives.
Note to self: Check that plug wires 4 & 6 are not swapped. :D :D

Thanks, Mike.

Glad things are working out for you with the Weber!
 
rixXJphx said:
Note to self: Check that plug wires 4 & 6 are not swapped. :D :D

Thanks, Mike.

Glad things are working out for you with the Weber!

I wish I could be of more help, but I have no idea about the 6-cyl. engine.

Happy New Year to you all
 
Back
Top