Author Topic: Need timing help! 86 K20 292 L6 SMOG delete  (Read 6334 times)

Offline thefarmboy21

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Need timing help! 86 K20 292 L6 SMOG delete
« on: March 04, 2014, 07:22:51 am »
I've been having several issues with my 86....my grandpa bought it new and passed it down to me. It now has a whopping 81,000miles on it. He and my dad say that it's never run like it should. Lately the smog pump has been SQUALLING, it spots, sputters, falls on it's face, backfires and has trouble pulling out of its tracks on a hill or with a load. Best mileage it's ever got since I've had it was 10.5mpg and worst was about 7mpg, but that's counting winter warm ups. It's driven like an old man would most of the time, tho I try to keep it cleaned out. It's got new plugs, wires, cap and rotor button and also a new fuel filter. I only run premium fuel also. None of this has helped much so I decided to take off all the smog crap, since the pump is shot anyway. While doing this I'm going to rebuild the carb (monojet with the electrical plugs) and I figured it would be a good idea to check the timing as well. It's a 292, 4-speed manual, 4x4, with 4.10 gears.

So, what timing should I have at what RPM? What should my idle speed be? And what are the tricks to rebuilding/tuning this monojet?

Thanks!
AMSOIL DEALER # 5583011
86 Chevy K20 Custom Deluxe-Grandpa bought it new 11/20/85
77 Chevy K10 Custom Deluxe-Dad's first truck
69 Chevy C30 flatbed-Grandpa's farm truck
1950 International L-112-Grandpa bought it new, parked in 1963

Offline Captkaos

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Re: Need timing help! 86 K20 292 L6 SMOG delete
« Reply #1 on: March 04, 2014, 01:41:48 pm »
Is the timing information no longer on the truck?

Offline thefarmboy21

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Re: Need timing help! 86 K20 292 L6 SMOG delete
« Reply #2 on: March 04, 2014, 03:20:29 pm »
I'm not sure? Where would it be? I have almost all the original stuff for it and the info tag is still in the glovebox, but haven't looked to see if it shows timing info. All the tags under the hood are there but they're caked/stained from leaky oil and farm dirt from the last 28 years.
Just now
AMSOIL DEALER # 5583011
86 Chevy K20 Custom Deluxe-Grandpa bought it new 11/20/85
77 Chevy K10 Custom Deluxe-Dad's first truck
69 Chevy C30 flatbed-Grandpa's farm truck
1950 International L-112-Grandpa bought it new, parked in 1963

Online bd

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Re: Need timing help! 86 K20 292 L6 SMOG delete
« Reply #3 on: March 04, 2014, 07:43:35 pm »
The emissions sticker with timing and tune-up information should be on the radiator support, right of center.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Captkaos

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Re: Need timing help! 86 K20 292 L6 SMOG delete
« Reply #4 on: March 04, 2014, 07:55:47 pm »
I would start at say 22 and then tune for the best vacuum.

Offline thefarmboy21

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Re: Need timing help! 86 K20 292 L6 SMOG delete
« Reply #5 on: March 05, 2014, 10:05:49 am »
I'll look but I don't recall seeing a tag with timing there.
0 Comments
   
What I've read else her says sonething like 8 degrees at 600rpm? How do you get 22? I can work a timing light ok, but all I know how to get is the base timing at idle speed. So elaborate in layman's terms if you would. Thanks. 
AMSOIL DEALER # 5583011
86 Chevy K20 Custom Deluxe-Grandpa bought it new 11/20/85
77 Chevy K10 Custom Deluxe-Dad's first truck
69 Chevy C30 flatbed-Grandpa's farm truck
1950 International L-112-Grandpa bought it new, parked in 1963

Offline Captkaos

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Re: Need timing help! 86 K20 292 L6 SMOG delete
« Reply #6 on: March 05, 2014, 01:07:03 pm »
Eight degrees initial is a good start.  Just get it idling find the timing tab point the timing light at the tab and see where the timing is and advance accordingly to get 8 initial.  To get total advance you need to play with the distributor springs, but if it is factory you should be fine.  Does it have any electronic controls connected to the distributor or just a coil and power wire.

I would put the #1 piston on top dead center and see if where the balancer line is prior to starting to establish if the outer right hasn't slipped.  If it has you need to put a mark on the balancer at 0...

Offline thefarmboy21

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Re: Need timing help! 86 K20 292 L6 SMOG delete
« Reply #7 on: March 05, 2014, 01:53:32 pm »
I don't think it's powering anything else, but there's a weird electronic box beside the distributor...dunno what it is. The dist is an HEI though. I'm pretty familiar with HEI's but I've always just tuned by ear. What rpm is the total timing checked at? And does the balancer marks go up to 22+ degrees? Thanks
AMSOIL DEALER # 5583011
86 Chevy K20 Custom Deluxe-Grandpa bought it new 11/20/85
77 Chevy K10 Custom Deluxe-Dad's first truck
69 Chevy C30 flatbed-Grandpa's farm truck
1950 International L-112-Grandpa bought it new, parked in 1963

Offline thefarmboy21

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Re: Need timing help! 86 K20 292 L6 SMOG delete
« Reply #8 on: March 07, 2014, 08:36:22 am »
Also, what is the 3rd line that runs into the fuel tank that was originally hooked into the vacuum canister? Is that the fuel tank vent or does it actually need hooked into vacuum? 
AMSOIL DEALER # 5583011
86 Chevy K20 Custom Deluxe-Grandpa bought it new 11/20/85
77 Chevy K10 Custom Deluxe-Dad's first truck
69 Chevy C30 flatbed-Grandpa's farm truck
1950 International L-112-Grandpa bought it new, parked in 1963

Offline thefarmboy21

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Re: Carb and fuel issue question
« Reply #9 on: March 09, 2014, 08:57:45 pm »
Not to high jack the thread, but I have an 86 with a 292.....where does the third line from the tank fuel sender go? One is main line of course, one is return, but what is the other??? I know it runs up all the way to the steering box and USED to hook to the charcoal/vac can, but what's it for? Does it need vaccum, or is it the vent and just needs left open? Can anyone shed some light? Thanks
AMSOIL DEALER # 5583011
86 Chevy K20 Custom Deluxe-Grandpa bought it new 11/20/85
77 Chevy K10 Custom Deluxe-Dad's first truck
69 Chevy C30 flatbed-Grandpa's farm truck
1950 International L-112-Grandpa bought it new, parked in 1963

Online bd

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Re: Carb and fuel issue question
« Reply #10 on: March 09, 2014, 09:47:51 pm »
Not to high jack the thread, but I have an 86 with a 292.....where does the third line from the tank fuel sender go? One is main line of course, one is return, but what is the other??? I know it runs up all the way to the steering box and USED to hook to the charcoal/vac can, but what's it for? Does it need vaccum, or is it the vent and just needs left open? Can anyone shed some light? Thanks

It's the fuel tank vent line. 

If you're not going to use a vapor canister (which is the preferred method to help control fuel odor), adapt a differential vent to the line, or plug the line and use a vented fuel tank cap.  The tank has to be vented so air can replace the fuel drawn from the tank.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline thefarmboy21

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Re: Need timing help! 86 K20 292 L6 SMOG delete
« Reply #11 on: March 10, 2014, 08:29:47 am »
That's what I thought it was but I saw a few people say to hook it into the car. I'm just going to put a rollover vent for a race car in it, OR a PCV valve which basically does the same thing. That what we always use on our derby cars. I found the timing stats too. Thanks
AMSOIL DEALER # 5583011
86 Chevy K20 Custom Deluxe-Grandpa bought it new 11/20/85
77 Chevy K10 Custom Deluxe-Dad's first truck
69 Chevy C30 flatbed-Grandpa's farm truck
1950 International L-112-Grandpa bought it new, parked in 1963