My Desmog Thread (5 Viewers)

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Here are pics of the final product. The one cap JimC sent me must have popped off the first day I drove her afterwards...so since this pic it now has OD Green 100mph tape in its place until I get another. I also removed the clamp from air cleaner inlet and replaced the screws to seal the two holes.

It is running great...starts without choke most mornings even below freezing...idles smoother than ever...pulls smooth up over 3000rpms every time instead of hitting flat spot around 2500. No issues, no pinging, no popping, nothing.

I did have to do the swap on the dizzy as JimC recommended....it was not pinging but was making it idle near 1000 rpms....swapping it got it down to about 700-750 per the oem Tach in dash. Thanks also to Trapper50cals pics with the orange lines....it helped clear up a few questions between the bar napkin drawing, instructions, and such.

took about 2 hours to get lines hooked back up and everything figured up after the hard work was completed since I did the following at same time:

-valve cover gasket
-manifold gasket
-crush washers and o-rings in oil cooler
-lots of cooling system hoses on radiator and from thermostat housing
-idler pulley with block off plate
-getting cat removed this week...plugged hose for now.

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I kept AC Idle up, dizzy advance and secondary, fuel decel cut, and couple others you can see. Removed HAC, EGR and BVSV I think and both sensors in thermostat housing. Runs Great.

Thanks to everyone especially JimC and Trapper50cal's photographs he posted.

If anything is wrong please let me know but as good as she is running with absolutely no issues since first time I fired her up in the garage to see where we stood....I cant imagine what it could be. Only thing I have not tested is my AC to see if it still idles up...LMAO
 
with a compilation of the trapper50cal plus that semi-legible component layout schematic with the x-s and s*** written on it.. i've got a list that will hopefully help some out:

HAC delete (specific)

Primary advance
• Advancer port on carburetor

Secondary advance
• Goes to port on air cleaner (3rd port)

Fuel deceleration
• Fuel cut port on carb. (top left) ( highest towards firewall)

Choke opener
• To air cleaner (2nd port)

VCV for EVAP (driver’s side)
• To aircleaner (1st port)
• BVSV
• Base of carb. Port (not modified)
• Evap canister (not modified)

BVSV (1)
• EGR R port on carb. (should be most forward port) toward headlights
• VCV on drivers side (top port)

Intake vacuum port
• Goes to three-prong gas filter on passenger side (bottom port)
• Replaced with single 1/8” port

CB
• Middle of three ports on carb (on front of carb)

what needs to be capped:
• Left and right ports are capped (on front of carburetor)
• Cap middle port on valve cover side of carb. (HAC Blow port)
• 2 large ports (26mm) where smog hoses attached
• EGR modification to allow PCV use
• Rear exhaust port should be plated or the down tube should be cut to allow for a plug to be welded ( allows proper seating which you won’t get from a flat plate)

A few questions (as mine is not running at the moment):

1. Is the above correct? I've done as he has, and tried to verify it against Trapper's pics. It seems correct.
2. One thing I can't seem to figure out is where Trapper's primary vac advance hose goes. It dips under the aircleaner in the pics, but I can't find the other side. Mine is currently hooked up as on the vac diagram--on the advancer port on the carb. Secondary goes to one of the open ports on the top of the aircleaner (or at least that's how I have it). Switching the primary with the secondary doesn't help at all.
3. Can this be done while leaving all of the EGR cooler crap stuck to the side of the block (even on the intake)? I have not even attempted to remove any of these parts yet. I keep feeling like I have a giant vacuum leak, but no open ports to block/reroute that I can find. The only thing I have not done yet (well, that I can find) is plug the exhaust pipe (the one that comes back up from under the driver's chair).

Symptoms, should it help:

Truck fires and runs, but runs rough. Must apply gas pedal at all times to keep it running, but can't just floor it, as it eventually dies again. Have to feather the pedal to keep it alive. When the choke is applied (50 deg here, so not technically necessary to begin running), the truck revs up to 2000, drops down to 1000, and cycles in between those numbers indefinitely.

Pics as quick as I can get my hands clean. Thanks all in advance.
 
Pics, as promised. It should be noted that the loose lines should connect to the missing air cleaner assembly. Hooking them all back up, with aircleaner in place does not change symptoms.

Also, and should have mentioned this...the BVSVs that were on the truck were both broken, even before I began the desmog. It's been replaced with a similarly threaded/similar looking part from a carbed mini (last pic).

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CruiserProblem-13.jpg
 
Thanks, Jim, as always. It should have been somewhat self-evident that an electrical switch needed a ground.

It's grounded now, and that stopped the cycling of RPMs from 1000 to 2000. She now runs smoothly, but only when choked. I still can't get it to idle properly. It also seems like it has a miss at higher RPMs.

Per the diagram, primary advance is hooked up to the advancer port on the carb. Secondary is connected to the air cleaner.

I'm reading through this entire thread again, but wondering if it's not a timing problem now. Others seem to have been required to retard or advance the timing.
 
Finally got it. From rereading most of what's been posted, it looked like adjustment of timing was necessary. When timing (moving the distributor in small amounts), it just wouldn't run--seemed to have a misfire.

Long story short, try not to desmog a rig when your coil is on its deathbed. I replaced it with a spare, and it's running beautifully.

On a side note, seems that minitruck BVSV will work, or at least has through a few runs around the block. Don't know about any long term effects, but will keep that advice in mind.
 
This 29 page thread is absolutley priceless! Thanks for all the pictures and expert input!!! Gotta love MUD!
 
started to re-trace and hook up the vacuum lines... realized that i only have one VCV. anyone have one they want to get rid of?
 
Just read this entire thread and it really cleared a few things up for me.

Jim- you sent me 6 air rail plugs, and one slightly larger plug. Im guessing that is for the BVSV. Which one? top / bottom , blue or pink? Thanks

- Milo
 
Thanks Jim.

i'll have a few more vac line questions as i finish up the hose routing next weekend.

About the Manifold i took off: when i took it off, it appears the upper and lower portions shifted slightly making the bolt / stud holes not perfectly round.. looks like its going to be a real pain to get it back on. do you have any tips on that? im sure you've done it a ton of times.

- Milo
 
Jim- thx for the tip on the manifold.


question: i went to pull BVSV #2 today and i noticed that BVSV 1, (top bvsv) has a broken nipple.

do the the sensors function the same? could i pull both and swap them ? i have a feeling finding a BVSV sensor by this weekend could be difficult / costly.


i need a solution for a broken nipple on BVSV 1


thanks,

Milo
 

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