1983 Mark VI won't start

[mercurygm88]

got a screwdriver? Thats usually how I do it. Pull one wire off a plug, stick a screwdriver in there and prop it somewhere thats about a pinky-wide gap.

so the duraspark only has 2 connectors? hm, I thought those had 3. One was input from the crank sensor, one was power input and output to the coil, and the third was spark advance control. Unless thats the setup on the MCU/VV cars I'm thinking of.

Two connector on the duraspark box. One is red and white wire. The other is orange, light blue, purple, and black. I won't be back down there until tomorrow but I found the good spark tester.

[mercurygm88]

Well isn't this fun. I went back through all of the receipts and service records for the car. Back in 1992 someone bought a double roller timing set. But I have no confirmation it was ever installed and even though the timing cover is painted blue and the rest of the engine is that Ford corporate gray color I'm thinking it wasn't I believe the nylon gears are still in there and that they fell apart enough that the timing jumped at least a few teeth. I haven't confirmed this yet, but judging by the lack of compression on the one cylinder I checked I'm thinking this is the issue. I don't know if pulling the distributor and sticking an inspection camera down there will show me anything but I think that's what I'm going to try. Honestly at this point I don't know if I'm going to spend the time replacing it or just try to sell the car as is. If I knew someone within a few hours drive who had done the job before I'd try to recruit them for help but I don't.

[kishy]

Low/no compression could certainly be caused by a cam timing problem. It would also explain a sudden problem that just appeared out of nowhere.

The timing set it pretty DIY-able, honestly. I've done it on 3 cars. There are definitely some gotchas to look out for, but I feel pretty confident that between myself and others here who've done it, we could arm you with the required knowledge and tips to get it done if you feel so inclined and can physically do it (especially on a Lincoln, it's a physically demanding task - the strain of bending over the front of the car is significant).

[gadget73]

The bigger possible issue is bent valves. The chain is easy, but if it smashed a valve because it jumped thats not so easy.

[kishy]

The bigger possible issue is bent valves. The chain is easy, but if it smashed a valve because it jumped thats not so easy.

I forget if we've hashed this out before - the prevailing opinion that I'm familiar with seems to be that no low output 302 was interference.
However, there are references out there to many of them being interference.
I'd have to defer to you on this one - if it is, or might be, yeah, it's a pretty significant concern and I was overlooking that.

OTOH this isn't black and white necessarily. If it jumped by a few teeth you'd end up with basically no compression but most likely the bits wouldn't have collided yet.

Inspection camera is probably wise at this stage. Or, rip it apart and verify the state of the chain and make decisions about how to proceed from there.

[gadget73]

I know a guy it happened to on an 84, though considering I didn't see the bent valves with my own eyes and that guy was more than a little bit of a hack there is a possible risk of bullshit involved. I can tell you with certainty I had a timing gear fall off an HO and no valve damage happened. Its going to be pretty obvious though, if the chain did in fact jump and replacing it doesn't give 8 cylinders with normal compression again something is quite wrong and you will know it right away. Just cranking it and listening will tell you.


either way if the chain was loose enough to jump, rocking the crank back and forth with a breaker bar while watching the rotor on the distributor ought to be a solid clue. If the crank moves a fair distance before the rotor does, thats not good. A tight chain will show very little crank rotation before the rotor follows along.

[mercurygm88]

I know a guy it happened to on an 84, though considering I didn't see the bent valves with my own eyes and that guy was more than a little bit of a hack there is a possible risk of bullshit involved. I can tell you with certainty I had a timing gear fall off an HO and no valve damage happened. Its going to be pretty obvious though, if the chain did in fact jump and replacing it doesn't give 8 cylinders with normal compression again something is quite wrong and you will know it right away. Just cranking it and listening will tell you.


either way if the chain was loose enough to jump, rocking the crank back and forth with a breaker bar while watching the rotor on the distributor ought to be a solid clue. If the crank moves a fair distance before the rotor does, thats not good. A tight chain will show very little crank rotation before the rotor follows along.

I have a sneaking suspicion that the compression tester I used may have issues. I have a known good one I'm going to try in the next few days. I'll also try to get a breaker bar and socket and see how far the crank moves compared to the rotor.

[mercurygm88]

So it turns out that both of my compression testers and the shop tester are bad. Or not sealing in the spark plug holes. I borrowed one today and all 8 cylinders are 140-150psi. I checked the fuel pressure and it was right around 40 lbs which appears to be right for CFI. Put the spark tester with the light bulb on it because I lost the other one again. Light bulb lights up, no start. Tried the screwdriver trick that gadget mentioned and no spark. So I don't know how the janky spark tester is telling me I have spark but I apparently don't.

I'm going to warranty out the Duraspark box tomorrow. Glad I kept the receipt in 2021 that thing was $14 now it's $125. If that doesn't work I'll have to try to find another crank sensor. That wasn't easy last time. I ended up buying a NOS on ebay when I bought the car just in case. 2 years later I needed it.

[gadget73]

make sure the connector for the crank sensor is clean. If that has crust it may not actually get a signal to the Dspark box.

[mercurygm88]

make sure the connector for the crank sensor is clean. If that has crust it may not actually get a signal to the Dspark box.

I cleaned out the crank position sensor connectors and the duraspark box connectors with contact cleaner. They looked pretty clean and still nothing. The new duraspark box will be in tomorrow morning. If that doesn't do it I'll have to order a crank position sensor. Hopefully that does it and it's not a wiring issue. When I first bought the car it would lose spark when hot that was summer 2021. I replaced the Ruraspark box and all was good until last February or March when it did it again. I warrantied the Duraspark box out then and it didn't do anything. So I replaced the crank sensor and that got it going. So both the NOS crank sensor and the off brand Duraspark box are only about a year old. But we all know how these parts can be these days.

[gadget73]

yeah, unfortunately the parts quality is questionable at best now. I'm becoming a hoarder of NOS/OEM parts even though I really don't want to be.

Just not that many parts to the system honestly so it shouldn't be that hard to diagnose

maybe if the dspark box doesn't fix it, before you go for a crank sensor just verify the coil actually has power both key-on and cranking and whether or not the other side is pulsing when the engine is cranked. Coils do die sometimes.

[mercurygm88]

yeah, unfortunately the parts quality is questionable at best now. I'm becoming a hoarder of NOS/OEM parts even though I really don't want to be.

Just not that many parts to the system honestly so it shouldn't be that hard to diagnose

maybe if the dspark box doesn't fix it, before you go for a crank sensor just verify the coil actually has power both key-on and cranking and whether or not the other side is pulsing when the engine is cranked. Coils do die sometimes.

Duraspark box did nothing. Haven't had a chance to throw a spark tester on it since, will check the coil has power. The coil is also less than 3 years old but then again who knows, does the ignition switch have anything to do with spark on EEC III? I'm hoping not, something tells me anything in the steering column isn't fun to work on.

[friskyfrankie]

If the coil test ok can you apply power directly to the coil, from the battery and see if there is power coming out and then to the distributor/plugs?

[gadget73]

Ignition switch will deliver power to it but that should be about it. I don't have wiring diagrams for an 83 specifically or EEC-III in general to see what else might be going on but if the blower and other key-on things work I doubt its the switch.

The switch isn't actually difficult to replace, just pull the plastic shroud off the bottom side of th column. I think the center panel under the wheel has to come off too, but thats 2 screws plus the 3 in the column cover. Switch is on the side right below the shift lever with 2 screws. Sometimes its a headless screw which is annoying to remove but not impossible. Stud extractors or a dremel to cut a slot in it for a screwdriver will get it out with minimal fuss. Stud extractor won't leave little metal shavings all through the car. If someone did it before it should be security torx.

[mercurygm88]

I've replaced the duraspark box, crank position sensor, and coil. Still no spark, no power to the coil, besides that I still swear I hear internal metal on metal noises. I gave up I don't have time for this and I need a vehicle, the grand marquis needs a transmission. So I sold the Mark VI to an older guy I know for $1500 which is only $300 less than I paid in 2021. I bought a 1992 K1500 4x4 with 70,000 miles on it as a daily driver for now.
So this older fella I sold the car to is a car guy. But he only understands carburetors, he thinks one of us needs to crank it over while one of us turns the distributor. I cannot in any way shape or form convince this guy that you can't do that on EECIII CFI. He simply will not listen, I even showed him that the distributor is keyed in place and he thinks that's some kind of Jerry rigged modification someone did. I told him I want to drain the oil and see if there's plastic in it, he doesn't want to spend $20 on 5 quarts of cheap oil to put back into it. I can't pull the distributor and put a inspection camera down there because nobody I know has one and none of the parts stores rent one.

I'm kind of at the point where the only thing I can do is tell him to have someone else look at it, he bought it it's his problem. But stupid me keeps helping out. I can't think of anything else I can do for free to try to figure this out and I can't convince this guy of anything because he already knows it all. And to be fair he does know a lot he built racing engines for 40 years, but he admittedly doesn't understand fuel injection and sure doesn't understand EECIII CFI.

So this is where I'm at and I'm kind of stuck. Part of me doesn't want to be an asshole and tell this guy to piss off, but I'm also fed up with his know it all bullshit.

Edit: So as is normal with every place I work all of the equipment in this shop is garbage. Test light is bad imagine that. I put a power probe on the battery 12. volts. With the key on I get 8.3 volts on the red wire going to the coil, 9.0 volts on the red wire going to the duraspark box. I don't know if this actually means anything but according to the spark tester I still have no spark.