Help with starting 79 k20 400SBC

kgerrish · Nov 25, 2024

Maybe just dump a little bit of gas down the carb and eliminate a fuel delivery issue. I just went through this on my NEW TO ME and first ever square body. 1985 K20

Craig Nedrow · Nov 25, 2024

Pull #1 spark plug out, have someone turn the motor with you plugging the spark plug hole with your thump, on the outside, no finger in the hole. when air starts to push past your thumb, you are on the compression stroke, watch your balancer, and stop when you see marks. If it is greasy, clean it up and as stated earlier, mark the balancer between 8-12 degrees BTDC. Pull cap look at rotor, it should be pointing at #1, ground plug on manifold and with ign on, turn dist cw viewed from past where the rotor lines up, then ccw until you see the plug spark. that procedure will confirm the timing is close enough to start.

peats · Nov 25, 2024

I agree with Nedrow, the timing is way out cause it spits and sputters when it was flipped 180. That means there is spark and fuel present.

Bextreme04 · Nov 25, 2024

Ricko1966 said:
Everybody,quit using brake cleaner,looking for intake leaks and as starting fluid,mounting tires etc. Burning brake cleaner creates phosgene gas. ( oh a little won't hurt anybody) yea,how much will? Why take a chance?

To be more specific, that is only chlorinated brake cleaner. The PERC that is contained in the chlorinated cleaners is a major carcinogenic substance and can indeed turn into phosgene when burned.

cduneman · Nov 27, 2024

Sgt Gus said:
Curious on status.

I got her going, ended up retorquing about everything under the hood, bought a new distributer and wires and plugs, and all new vaccum lines and one of them got it going, not sure what one though .

It idles and revs amazingly but has very low power, and when driven for more than a few miles the coolant starts to bubble and steam out of the radiator. From what I can tell the engine does not overheat though..... I replaced the thermostat and all the coolant hoses and am honestly stumped. Brand new head gasket and piston rings so that should not be the problem.

Craig Nedrow · Nov 28, 2024

That is defidently a pressure leak into the coolant,cracked head, head gasket, etc

chasw44 · Nov 29, 2024

yep, the leak is probably from not torqueing the heads correctly or not resurfacing the heads or needing better headgaskets that thin metal ones. good gaskets for rebuilds are not cheap. probably a waste of time but coolant in the cylinder will make that plug look really clean. a shortcut can be stopleak for a very small headgasket leak after retorking the heads. do you have a thermostat bypass hooked up? to get coolant around the thermostat till it warms up?

Help with starting 79 k20 400SBC

kgerrish

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Craig Nedrow

NADAR UNDER THE RADAR

peats

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Bextreme04

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cduneman

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Craig Nedrow

NADAR UNDER THE RADAR

chasw44

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