runs like poop. How do I troubleshoot duraspark + will it run 180 out??

[v8only]

I've got the carb dialed in what I think fairly healthy now on my 66. (5.0 roller crate motor)..the carb is very responsive with no hesitation.

Problem is, it runs like crap. It sputters and shakes throughout the rpm range.

the motor is a known good motor.

I'm running an 85 distributor through an autozone duraspark box into an accel coil.

The stock ballast resistor goes to the + side of the coil with about 7 volts going to it. I wired key on 12v to the duraspark box.

Will it run if I have it 180 out??

I can pull one plug wire after another, and to tell you the truth, it's like none of them make a difference at all, or make very little difference at all, so It doesn't seem to be just one cylinder or two that is the problem.

Weak spark?? How could I troubleshoot that?

Not sure where and how to start on this...Thanks again all!

[gdniel]

Sounds just like when I put my old 302 together and the timing wasn't what I thought it was.

[JACook]

Will it run if I have it 180 out??

It will if you're also using the wrong firing order, or perhaps wired it clockwise,
rather than anti-clockwise.

[82mustang]

check firing order of the cam.. then on the distributor cap, i had that issue before.. i know its obvious but make sure you know which cylinder #1 is(the front cylinder with the head thats furthest forward), make sure its on the compression stroke when you put the distributor pointing at that terminal on the cap.. good luck

[79Coupe]

Three words.... M S D



... ok seriously, I'd check the firing order and timing. Roll it over to TDC on #1 and start from there.

[84ttopnotch]

i was thinking firing order too, 302HO is different from non ho.

[varn82]

i was thinking firing order too, 302HO is different from non ho.

first thing that came to mind as well. or just one set of crossed wires? i know i have done that before, and it will idle fine, but as soon as you wack it, not so much.

[v8only]

i've checked and rechecked the firing order, it's wired HO style.

Curious though, when I pulled it apart It didn't have the typical spider web in the intake valley, rather it had a bar that connected two of the lifters together...

what's the easiest way to tell if I some how have a NON ho engine firing order?

[lxcoupe86]

Sounds like a timing issue for sure. Sounds like it is waaaaaaaay retarded. I can't see how it would even start if it were 180 degrees off... Go basic, pull the #1 plug, turn the motor over by hand or tap the solenoid with a screwdriver until you feel the compression stroke coming around (air blowing out the spark plug hole) then put the timing at 10 BTDC on the balancer). Then, stab the distributor, making sure the rotor points towards the 11:30 position. It may take you a few stabs to get it right but eventually it'll go in there. Make sure you have the correct 1-3-7-2-6-5-4-8 and she should start right up!

We had a similar issue on our GT40P motor startup in our 82 Capri, we also used a Vatozone 85GT distributor, but we used an MSD 6AL instead of a Duraspark box... what are you gonna do if you miss a shift with the the Duraspark?

[v8only]

I'm just going to have to not miss a shift. msd is not in my budget.

I verified the firing order today as an HO firing order...

I pulled the valve covers...and watched the rockers...each set of rockers in order of the HO firing order were on the base lobe as I rotated the cam, which I believe to be the compression stroke.

The only thing I can see that was wrong is that the button on my distributor cap in the middle was seized. usually that button is spring loaded.

I'm going to change my cap and rotor tomorrow and try firing it up again. maybe I'll pick up a vacuum gauge (last one broke) and try messing with the timing without a light to see if it gets better. Perhaps the dist is way off from what it really says??

We'll see tomorrow.

[69SCJ]

That ball (contact) in the cap could be it.

If that doesn't fix it be sure you have No. at TDC on compression. I just pull the No. 1 plug and put my thumb over the hole while I turn the motor by hand. You feel the air squishing past your thumb on the compression stroke.

I still suspect firing order since it runs 180 out and correct though.

Good luck, and let us know.

[Cappn Tripps]

The link bar lifters makes me wonder what cam is in it. And if they're solid rollers. Does anyone even make hyd roller lifters that dont use the spider and dog bones? What year is the engine anyway?

[v8only]

I found a picture of it with the intake off.

It does have a spider, but does have some sort of link bar too...never seen it done this way

[svocapri]

Are those gt40 Y303 heads? I got a set of those for my car but couldn't run the factory rockers as the valve spring retainers are larger and there was interference. I have a Comp Cams 266hr with ~.540 lift so that may be different for you. I would check the rockers though.

[v8only]

those are gt40y heads.

it is supposedly a ford racing crate motor, and those are the rockers it came with. IT's been run with these rockers for about 50k miles, so they shouldn't be the issue.

I'm going to replace the cap and wires on my lunch break. I'll get back to you if that makes the difference. I'm skeptical, as it looks like contact was still being made with that center carbon button...even though it wasn't moving, it was making contact with the rotor

[JACook]

Those "link bars" are the later Explorer style lifter guides.

A Duraspark cap does not have a spring-loaded button.

The distributor turns counter-clockwise, looking down from above. Make sure you've
wired the cap accordingly.

<edit>
The spark plugs should give you a good indication of what's wrong.

<correction>
If the distributor is 180* out -and- the cap is wired clockwise, the engine will
try to on 2 cylinders. For an HO firing order engine, those would be 4 and 7.
</correction>

If the distributor is 180* out, and the wrong firing order is used, it will run on 4
cylinders. Those would be 3, 4, 5 and 7. If the distributor is indexed correctly,
and the wrong firing order is used, it will still run on 4 cylinders. 1, 2, 6 and 8.

If the plugs tell you that 1, 4, 6 and 7 are good, or 2, 3, 5 and 8, then you've got
carburetor or vacuum leak issues.

You can also use a spray mist bottle and water on the headers to see which ones
are firing, and which ones are not.
</edit>

[lxcoupe86]

Those plastic things as JACook said are the later Explorer lifter spiders... we had them on our 99 GT40P motor but tossed them in favor of the regular 85+ spiders.

What is that bolt with 7 nuts on it?

[v8only]

you like that bolt?? LOL. I wanted to put the timing cover on with all new bolts, but didn't have them yet, so I improvised until I got the right bolts, which are on it now.

I'm headed home for lunch...wish me luck

[v8only]

ok, I've got it all back together again, and here is what I found.
I put the balancer on 0, which is tdc #1 compression stroke, verified (I stabbed the dist 180 out and it wouldn't run..just backfired)

so I stabbed the dist right and fired it up, it ran like crap.

Then I took the dist and advanced it as far as I could until it hit the water neck...so that's going clockwise I believe. I advanced it as far as I could and tightened it. Fired it up and night and day difference.

It's def running on all 8. (wired the HO pattern) I've still got a slight miss and think it needs even more advance.

here is the kicker though...I advanced it till what says is 40 degrees of advance at idle, and I think it still wants more.

I then try and hook up the vacuum advance hose to it, and it wants to stall.

Opinions?? At least we're making some progress!!!

[Cappn Tripps]

BTW, what did you gap the plugs at?

[86capriASC]

sounds like you are off a tooth

[v8only]

45-50k I think?? I gapped em for an 85 mustang..

btw, here is my theory. Since I had to advance it so much, I think I'm a tooth off. However, the fact that I've verified tdc and #1 on the dist, yet it's a tooth off means something is way out of wack, perhaps the dist??

as well, on a 4160 holley carb, which one is ported vacuum?? On my carb, I've got two vacuum lines coming off of the pass front. One at the base front of the carb, and one higher than that. I'm using the lower one, but I'm thinking that it's the wrong one perhaps

[jc306na]

When you're dropping in the distributor, you're rotating the entire body of the distributor to match the rotation of the rotor, correct? If you're letting the rotor turn but dropping the distributor body straight down, you're killing the timing setting, effectively putting you in the neighborhood of "1 tooth off".

When you have the motor at TDC, verify that the timing tab is pointing at zero. Take out the distributor and line up the rotor with the number one post. With a marker, mark the outside of the distrubutor on the lower cap to show where the rotor is pointing at spark plug post number 1. Turn the motor until the pointer is at 10 degrees btdc or so, then drop the distributor in, making sure that you have the rotor pointing at the mark when you get the distributor bottomed out. If it's not, turn the distributor housing to line up the rotor with the mark. This should get you to the ballpark of 6 btdc to 14 btdc, and running pretty well. Set your timing with a light, and go get 'em!

[69SCJ]

I agree with the above post. When you drop the dizzy it rotates because of the angle on the gears. You most likely are off one tooth.

Once dropped you know the rotor is supposed to be on number one so make sure that where the rotor points is on number one (of the cap).

I wouldn't do it, but you could move every wire over one space (on the cap)and accomplish the same thing.

Tyler

[lxcoupe86]

Jeremy, don't concern yourself too much with one tooth off, one tooth this that, it's just technical jargon for the range of which you can advance/ retard timing without hitting the water neck.

Try bringing everything to TDC, instead of putting the timing point on 0, put it on 10 BTDC, I've had much better luck with that... Line up the rotor to the #1 plug wire on the cap... so both the rotor and the #1 plug wire are pointed towards 11:30. When you stab the distributor to 11:30, it'll only go in one way ... you'll know when you get it in there. Then, 13726548 she should start right up and purr like a kitten if everything else is in order and you'll be able to time it at that point... Are you sure the vacuum advance hose is plugged into the advance port on the side of the carb and not an engine manifold vacuum source?