Black Smoke at Idle - Burns My Eyes

[Solace in Solitude]

Hi Everyone,

Edit: a friend just suggested that, since my 2F is the original engine and has apparently never been rebuilt, the FSM-specified .014" is no longer enough to allow the exhaust valves to fully open. Is this a possibility that would result in this toxic, black, sooty smoke?

I posted this thread ( https://forum.ih8mud.com/threads/hoping-for-guidance-validation.818800/page-2#post-9378057) after my maiden trip in 44 and I got a lot of good suggestions.

My plan was to get the replacement fuel pump from Beno, install it and work the plan...

But, FedEx got lost and my pump didn't arrive until Friday afternoon.

So, in the meantime, I checked my timing and found the bolt that clinches the distributer collar had snapped. I replaced the bolt and set the timing to 7*BTDC.

Then, I pulled the valve cover and adjusted the valves, replaced the cover and pulled the plugs - they were all fouled - black and sooty. I cleaned the plugs and re-gapped them at .039" and reinstalled them.

When I started 44, I found copious amounts of black, sooty smoke coming out of the tail pipe, instantly burns my eyes.

I also found my idle vacuum had dropped from 17" to 13".

First thing I did was read Vacuum 101 in the FAQ - I pulled the air cleaner and sprayed water on everything,
All vacuum hoses the base of the carb, the intake manifold and the intake manifold gasket - I've done this a number of times, I'm can't find any vacuum leak. It's not the brake booster either.

Next, I read up on black smoke and learned it points toward unburned fuel. Note: I then read Ed Cook's "Cruiser Carb Info", in the FAQ and searched for anything related to black smoke. I found several threads that mentioned the "Lean Drop Method" and some Fj40Jim ( who recently rebuilt my carb) suggestions to : set idle to 650rpm, set timing to 10* BTDC for a '77), screw idle mixture in until engine starts to die, screw it back out to the top idle, adjust idle to 650 rpm...

My 40 never tries to die when I screw in the idle mix.

I also read where Mark (65swb45) suggested choke sticking or linkage sticking. I disconnected the choke and checked the linkage - no help.

I'm running at 650rpm, 7* BTDC, with 13" of vacuum and it drives GREAT, but the idle is killing me... And it just took me an hour to clean the black off the garage floor.

I'll be out of town all week and will pick this up again on Friday evening.

If anyone can tell me what I need to do to correct this, you'll be my HERO, ' cuz, I'm LOST!!

Thanks,

 

[subzali]

Sounds to me like you're either over fuelling or under sparking somehow. So here's a bump since the weekend is coming up.

You might also take a look at this and other threads where Pin_Head and/or FJ40Jim talk about overfueling/high idle issues: https://forum.ih8mud.com/threads/fj40-2f-carby-rich-idle.818723/

 

[Solace in Solitude]

Thanks Matt!

I spoke to Jim before I left town and he said I was flooding it with gas. He suggested the secondary spring might be stuck. I found that even though I disconnected the choke cable, the choke breaker was stuck.

I was a little late leaving, but just need to tweak it when I get back home.

All is good!

Thanks for responding!