hey everyone, i had my slant running pretty good before it sat over the winter. once i had it parked i did a compression check (with all the plugs out) and found low compression across all cylinders, after checking and setting the clearance while running (as hot as i could get it) i got my compression up to 110ish in all vs 80 ish across. Anyway since the intial compression check i have devolped a miss at idle, and when i tried to drive it when i hit the gas it bogs and and pops, from a stand still or roll. it drove fine before i ever did the first compression check and i have slack in the timing chain (which is going to be replaced) but it drove fine last year with the slack. I found what i think is pretty close to TDC in #1 (using a pick in the bore for feel)and had the balancer at the timing mark at zero, and then took the pic of the rotor, to me it seems early but i am new at this, what do you guys think? My thought is that the chain jumped when i did the compression check with no plugs in it since there is slack and was not load on the engine.

I rebuilt the carb over the winter since i had a kit and a new float anyway, the carb was put through an ultrasonic cleaner multiple times so should be good to go. I also get a good healthy shot of fuel when i hit the throttle linkage by hand so i think my accelerator pump is working fine (its new with the rebuild)

the engine is in a 78 D100 from california but i am not sure if its the original engine or distributor.

any thoughts on the rotor position? or other things to check?
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Re-check the dumb stuff first- did a vac. nipple crack or fly off? Is the carb sealed to the intake? Cracked or disconnected vac line or pcv or brake booster? Is the needle and seat stuck and flooding? All cyls have ignition parts in good nick?

Good luck

How old is the fuel? Here in CA, the gas loses its punch after a few months.
I had water in the tank of the Duster once. It would idle but pop and stall if I leaned on the motor in gear. I drained the tank and while most of it was gasoline, about a quart looked like Italian salad dressing.

Vacuum leak? crossed plug wires? i find that going back to the last thing I did leads me to most of the trouble I have. If not first thing I'd do is check the chain and balancer. If the timing mark bounced around a lot when you set the timing the chain is probably worn. Turn the crank until the rotor moves,notice how far you have to turn the crank before it moves when turning the other way.To see if the timing mark on the balancer has slipped(common on slants). Thread an old spark plug for a bolt you've ground round on the end or buy a positive stop,run it in #1 spark plug hole and turn the crank BY HAND(breaker bar is OK but don't use the starter) until it stops. Mark the damper with a piece of chalk or paint at a reference point on the timing cover(usualy the timing tab,turm the crank the other way until it stops and mark the damper again. The place between the two marks is TDC on #1. This is where the "0" mark on the damper should be. If so you're done. If not remove the stop. While you're turning this anyway you may as well check the condition and gap of the points. Make a mark halfway between the marks you made,bring the mark to the timing tab at the factory setting turning the crank clockwise. At this time the points should be starting to open with the rotor pointed at #1. If not grab the test light,make sure it works,set it aside . Turn the Dist. in the direction of rotation until you're sure the points are closed,turn the ignition on and check the Neg. side of the coil(the one that goes to the Dist)for power. There should be none since the points are grounded. Turn the Dist. against the direction of rotation until the test light lights. Your timing is set,lock 'er down.
If nothing shows here it's time to go after the carb
Ron

Maybe the rotor?
That spring pickup for the dist. cap center contact
looks crookedy?

Joe

What joe said. It ran fine before the low compression test. What's your initial timing?

Where is the rotor in relation to #1 on the cap?

As said before, check for total play in the chain. About the only thing that will drop the squeeze in the whole motor is cam timing.

110 isn't real bad for a Slant. 20-30 or so low, but not terrible.

You may have answered your own question. "It ran fine before I adjusted the valves". If they're to tight it will hold the valve open. It will run poorly,pop,and miss. How did you adjust them while running?
Doug

good eyes everyone, i missed the bent rotor too, i straightened it out and tried it again but it still misses and pops when i rev it and stalls once in gear. truck ran good before the intial compression test and before sitting over the winter, the valve adjustment had no effect other than bringin up the compression readings abit. i put some 91 octane gas and stabil in the gas tank before storing but maybe my gas still went bad, i am going to go over some more suggestions today.

I did the valve adjustment running like the procedure on a slant forum i found, i waited till it was as hot as it would get on idle and set them a tad loose for the hot setting

Plugs, cap and wires are in good shape, i really hoped that rotor being bent was going to rix it lol