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Discussion Starter #1
Hi! I have a 68 -HT with a 74-ford 302 that untill a few weeks ago have been behaving great. One morning it suddenly wouldnt start instantly as it has always done, it took 10-15 minutes of trying and then it suddenly started.

After that its gotten even worse, and now it does not start at all unless we turn the distrubutor to delay the timing. When it starts at that delay, it runs bad, so we turn it over to the normal position where it was before this issue, and then it idles great, but at high RPMs its vibrating heavily and runs rough.

Since the engine is a 74, its got the timing mark on the passenger side, which we cannot see because of the water pump, so we tried to make a new mark on the driver side. We marked a spot in the balancer and block where the piston was at top on the compression stroke (valves closed), the wierd thing is that at this point, the rotor in the distributor points between #1 and #5 spark plug wire (it has passed #1).

We talked to some people which were certain this was a timing chain jump-problem, so yesterday i took it all apart, and to my disapointment, it looks like the marks on the gears line up as they should(cam-gear mark at 6:00, crank gear at 12:00).

We have tried to troubleshoot this issue for several weeks now, but we are not getting any closer here. Does anyone here have an idea of what the problem could be here?

What we have tested:

Compression: around 150 PSI at all cylinders
Spark-plugs: Dont look too bad, whitish color
Coil: Measured 1,8 ohm between + and - .
Distributor(pertronix module): we removed this and checked for wear, it looks okay.
Carb(motorcraft 2100): We installed an overhaul kit and replaced valves and gaskets.

Hope someone can give me some suggestions, thanks!
 

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Have you checked the gear on your dist. It sounds to like you may have jumped there. Not on the timing chain. Reinstall tdc on compression. Make sure dist is pointing at 1. If not pull up turn 1 tooth reinstall. Let me know if that doesn't work. If it does work and there is wear on the gear. Just replace it.
 

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Discussion Starter #3
Have you checked the gear on your dist. It sounds to like you may have jumped there. Not on the timing chain. Reinstall tdc on compression. Make sure dist is pointing at 1. If not pull up turn 1 tooth reinstall. Let me know if that doesn't work. If it does work and there is wear on the gear. Just replace it.
We did remove the dist and took a look at the gear, it didnt have any massive sings of wear, but i didnt even know it could jump because its really tight. i will check this tomorrow.
 

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I sincerely doubt the distributor gear jumped a tooth.
If it was installed a tooth out you'd still be able to rotate the distributor to compensate for it, and set your timing just fine.

Without having accurate timing marks to set your timing with a light, just set it to where it'll start, and stay running.

Once it's running check the dwell, and adjust the points, idle & mixture to where it runs the smoothest, and take it for a spin. Slowly advance the timing until it starts pinging under a load then back off the timing until it doesn't.

Another thing to check is your choke. Make sure it's opening as it warms up. If it's not that can surely cause that rough running at high rpm!

Hope this helps
-Paul
 

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Discussion Starter #6
Have you checked for fuel delivery? Pump, filter etc?
Fuel delivery should be okay, it has good pressure, carb squirts at pedal-depress. Carb-filter is new, gas tank filter is also new.

I just checked the dist today, and it might make sense if it has jumped a tooth, because it pointed directly at #1 when reseated it. Since the weather here in norway does not allow winter-driving, im storing it for the winter, and i will try this new setup when i get the timing cover back on when i get the new gaskets..
 

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Discussion Starter #7
Update: we assembled the engine today, with the new timing chain it has no slack. We lined up the marks on the gears and checked that #1 piston were at top. We then set the distributor 1 tooth off (clockwise) so that the rotor pointed at the #1 spark plug wire - Couldnt get it to start.

Then we set the distributor back to where it was before we started fiddling with it, then the rotor points between #5 and #1 (closer to #5) - it started and ran pretty good, we kept giving throttle and testing at high rpm etc, we set the timing to 10 degrees on idle, and at max throttle without vacuum advance connected it showed 40 degrees. If we connected the vacuum advance, the timing at high rpm would go way up over 40(off the scale) and it would not run good, so we kept this disconnected.

Sudenly the engine didnt respond well to quick pedal-actions, and started hesitating when accelerating. All of a sudden, it stopped. After this we tried to start it again, but it would not fire.. Then we set the distributor the way we got it to start before, then it starts. Timing mark showed around 30 at idle and it runs crappy, we then move the timign to 10 degrees again and it idles good.


So we are basicly back to the start. The only difference is that we made a new timing mark based on the original one we could not see with the water pump on.
It seems like theres multiple problems here.. so we tested a spark plug just to see, and the spark was blue/whitish but it was a little inconsistent, sometimes it was brighter etc. So maybe the coil has gone bad?

I have no clue how to proceed testing now, as the problems make no sense to me at all. Its tempting to just buy all new ignition components (dist, coil, carb, spark plugs) but before we do this, it would be great to hear some thoughts on this.

Hope this wasn't too confusing to read, but its a really wierd problem so its hard to explain in a good way :p
 

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Discussion Starter #8
Just noticed the coil is leaking oil and is almost empty... This is probaly why the spark was so inconsistent, so we are buying a new one. Hopefully it win fix some of the issues :D
 
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