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have newly acquired '79 j10 360 ci. 2bbl. motorcraft 4x4. After putting new plugs, cap and rotor (and plug wires) and timing @ 13deg. adv. it sounds great revved up in neutral but on the road 10-15 mph tops & sounds terrible. It ran ok when first purchased but after tune-up not so good. Only other things I did were correct plug wires (had #1 on #8) adj. idle mixture, and rotated dist. to 4'cclock instead of 6'oclock(facing eng.) At six o'clock vacuum diapharm would hit belt trying to time. All help appreciated! mike cody wy.

Welcome to the site.

Sounds like you need to start with the basics and re-time the ignition timing because it sounds like it wasn't correct to begin with. I think you need to roll the engine over to TDC and set the timing from there.

Perhaps get a manual if you don't know how to do this? There are lots and lots of 'methods' to determine TDC.

Blake, I had my son bump starter until compression blew air past finger on number one and rotor pointed to proper position. I then rotated dist. after turning oil pump slot to where I thought it needed to be to position dist. away from belt (around four o'clock) Dist. slid in on first try. Is this different tdc procedure than you suggested? Could my moving the dist. in this manner be causing the "no power" when appling load while driving?

that sounds like the correct procedure.

When you found TDC, did the timing marks on the harmonic balancer indicate 0 ?

Is there room to advance the dist more now?

Blake, didn't check zero to scale but if it doesn't is dist in wrong location? I read on this forum you can move a tooth or two over to help time. Maybe previous owner had done this and that's why diaphragm was facing belt and plug wires were off but it still ran ok (45-50mph) not a lot of power for a 360. Set timing to 8 btdc by manual . Barely starts but dies. 13deg. atdc seems to start the best and revves up decent.

carnuck, had plent of room after dist. move

Blake, went back and set #1 @ tdc on comp. stroke and of coursre balancer doesn't line up w/ tdc on scale. Can't find in manual a way to reset dist. to line up. Do you pull dist. and turn gear couple teeth one way or the other? bal. line is @ 12o'clock so I rotate gear clockwise? thanks

how do you determine original dist. position when it was out when purchased and I've moved it twice. did it come new with some kind of matchmarks? Think I can get this j10 running knowing this. I love this truck, window rolls up w/ 2 turns on the handle amazing! I have an 86 chevy and 98 f250 takes seven turns to close them up. Great ride and good highway gears can't wait to start driving to work! Thanks for the help

Welcome to the Network...

Wrench the balancer to TDC comp, Look at where your rotor is pointed, and use the terminal after it as #1. Should give you enough adjustment to play with.

If you can leave it just loose enough to move the dist while running, move the dist CCW in small increments and listen to the motor. A vacuum gauge taken to the highest point then back off slightly works too. Eventually, get it to a timing light to adjust. #1 is front driver's side and the timing mark comes up twice during the 4 cycles of the motor.

how do you remove bowl to access power valve when bowl has two screws (removed) on outside and inside has two pins w/ tapered head looks like they were drifted into place. I've seen pics of other motorcraft carbs and they had screws in all four corners to remove bowl top. help much appreciated. Still working on this one !

Sounds like a shop may have put in a powervalve plug (blocking it off) and didn't want anyone messing with it.

If you can confirm that the #1 cylinder is at TDC on compression, and your balancer is NOT pointing to zero, then either the Cam was not installed "straight up" or the timing plate next to the balancer has been moved, or it has the wrong balancer on it. Confirm either way by pulling the drivers valve cover and checking that the #1 intake and exhaust valves are both fully closed. If they are then re-stab the distributor with the rotor pointing fully forward, that'll be your #1 cylinder plug wire tower.

carnuck: I'm the third owner ,both before used truck on ranch only(co.,wy.) Don't see the need for this powervalve plug but what do I know... truck has 88k miles & good comp. Thanks

Haminawag: I've thought from day one I had dist. in wrong position and in fact when first purchased dist. faced straight forward. Manual shows a four o'clock pos. and the straight forward pos, seemed to conflict with belt/timing (too close to belt) and I've been led to think ucan stab dist. anywhere as long as on comp. stroke mark on bal. lined up with tdc and you tweek rotor to point to #1. I'll try your suggestion and if that doesn't help its either powervalve(spring seems fine) or coil (starts ok) but metered out of spec. a small amount. Thanks for the help

Powervalve is internal to the carb.

Timing is WAY off, and I mean WAY off.

Could also be a choke plate stuck closed.

whatever happened to the OP?