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Engine miss

Discussion in '"Stock" Alpine' started by Eleven, Jun 28, 2019.

  1. Eleven

    Eleven Gold Level Sponsor

    All my questions have been aimed at tracing a slight miss that is developing (except the one about hard starting which I suspect is related). The engine felt lumpy a month or so ago and then I have noticed a bit of a miss. When I accelerate it revs nicely but at a steady pace it gets bumpy again.
    To date on my SV I have done this:
    New plugs (old ones were clean and looked a bit lean but changed then anyway. I mentioned a few weeks ago that I thought I was oiling plug but have not seen evidence of that with the new ones), new wires, swapped the Pertronix coil for another (did nothing so the Pertronix is back in), adjusted the valves, reset the float, went through the Weber carb jetting and found some wide variances, corrected those. Reset the choke so be sure that it opened all the way up. Timed the engine. Upped the fuel pressure, was a bit low. Cylinder pressure is: #1 120, #2 123, # # 115 ( or a bit more), #4 110. All are very low and #4 looks discouraging but I don't think any of these numbers will cause a miss, just poor performance.
    So, I noticed two things:
    When a plug wire is disconnected the primary terminal arcs to the coil casing. It did this with the substitute coil also so am not sure that is an issue.
    The when I put my hand over the oil fill cap, I get a fair amount of blowing. I placed a dollar bill at the exhaust pipe and it did not suck it in. Years ago I was taught that if there was good pressure in the valve cover, yo probably had an intake seal of guide going bad. Is that true?
  2. RootesRooter

    RootesRooter Platinum Level Sponsor

    My Weber-ized SV had these same lumpy running symptoms a few weeks ago. Turned out the intake manifold bolts were loose.
  3. Barry

    Barry Platinum Level Sponsor

    Fluids (including gases) move from higher pressure to lower pressure. The intake manifold on a naturally aspirated engine is lower pressure, so a leaking valve guide / seal would result in air moving from the crankcase into the manifold and would not result in air blowing out of the valve cover.

    Air blowing out of the valve cover indicates higher pressure in the crankcase. I would put my money on air moving from a combustion chamber(s) into the crankcase (aka, "blow by").
    Last edited: Jun 28, 2019
  4. puff4

    puff4 Gold Level Sponsor

  5. Eleven

    Eleven Gold Level Sponsor

    Thank you Dick and Barry! I hope Dick is right but fear I have serious blow by given the compression.
  6. Eleven

    Eleven Gold Level Sponsor

    I have new wires so why does it? I took the cap to the coil wire off and it arced. I have never seen this before. I have 7mm wire on the car. When I was looking for the missing cylinder, I pulled wires one at a time and each time it arced, regardless of which coil I used.
  7. puff4

    puff4 Gold Level Sponsor

    Well, I don’t know about what new wires you have, but again, you should not see arcing. I’d do those first two tests and I suspect the second one will fail. If you have a friend nearby with another cap and wires I’d give that a quick try.
  8. Tom H

    Tom H Platinum Level Sponsor

    Tracy, you say it arcs from the primary to the case. I'm thinking you really mean from the secondary, i.e. the high voltage terminal, correct? The primary is the 12 V terminal. Or are you saying it really arcs at the 12 V terminal? If so, that is puzzling.

    Assuming you mean it arcs at the high voltage terminal, that is somewhat normal. and could indicate that your coil is putting out more voltage than the insulation and distance can handle. Whenever you disconnect one of the high voltage wires, whether the main wire from coil to cap or one of the spark wires, you are stressing the system. There is a lot of voltage, 40 killovolts or more, at the tip of the coil, with no where to go. When connected, that 40 KV causes the arc to happen at the plug tip, but with no grounded plug connected, it will try to jump at the weakest point in the system. If the high voltage tip of the coil is a bit damp, or dirty , or has a carbon path on it from a previous arc, the arc will occur there.

    A good, solid, high voltage system - coil, wires, cap, etc is designed to contain the max voltage the coil will put out, but with no plug connected, the system is being stressed, especially if teh coil is putting out more voltage than the system was designed for. I'm still skeptical about your pertronix coil. Are you sure it has an internal ballast resistor? Or is it designed to work with an external ballast. If so it may be getting more input voltage than it was expecting and therefor putting out more high voltage than expected, more voltage than the insulation can contain.

    Last edited: Jun 29, 2019
  9. Eleven

    Eleven Gold Level Sponsor

    Thank you Tom. Yes secondary, my error. Tough to trouble shoot when the patient gives you bad information! The Pertronix site said internal but I can try an external if it won't hurt anything if it is internal and can figure out how to wire it. Kevin, I am going to try those tests; no reason not to check everything.
    Would the standard Alpine wiring diagram show how to wire the external ballast resistor?
  10. 65beam

    65beam Bronze Level Sponsor

    Does this help? Regular 1967 date coded Lucas coil with Pertronic unit instead of points. 100_0548.JPG
  11. Tom H

    Tom H Platinum Level Sponsor

    Tracy, No, the standard Alpine wiring diagram, any series, does NOT show the wiring of the external ballast. But figure 34 on page B 43 of WSM145 does show the proper wiring. But it's really quite simple. 65Beam's photo shows it pretty well. Even of you do not have the bypass wire coming across the firewall, you can easily install the ballast without the bypass circuit and it should start OK unless very cold.

  12. puff4

    puff4 Gold Level Sponsor

    What Tom said.

    I’m up at the lake house, so this is from memory (Tom, feel free to correct me!), but I believe the wiring is as follows:

    - Red (? not sure this correct color ?) wire from spade terminal on starter solenoid goes to first spade + terminal on coil. (This solenoid terminal is only hot when ignition switch is in “start” position.)

    - White wire from ignition switch goes to single spade terminal on ballast. (This wire is only hot when ignition switch is in “run” position.)

    - White (w/ black tracer?) wire goes from the opposite spade terminal on ballast to second spade +terminal on coil.

    On some cars, like 65Beam’s, I’ve seen the red solenoid wire go to the second terminal on the ballast. The result is the same.
    Last edited: Jun 29, 2019
  13. Tom H

    Tom H Platinum Level Sponsor

    Kevin, Tracy, this is just about correct, with a few corrections:

    1) I think the wire from the solenoid is a red/white (or green white?) wire in a plastic sleeve. But this is the "bypass" wire that Tracy may not have and probably does not need unless starting in very cold weather.

    2) Yes, the White wire from the ignition goes to the spade terminal on the ballast. This wire is presently connected directly to the Coil and needs to move from there to the ballast resistor. And Tracy also has, almost certainly, a red wire, to power the Pertronix circuit in the distributor, presently connected to that same terminal on the coil. That wire also needs to move to the Ballast resistor, same end of he Ballast resistor as the white wire from the ignition switch. (you can see in 65Beam;s photo the white wire and red wire at the right end of the Ballast)

    3)Yes, a short wire from ballast to coil.

    alpine_64 likes this.
  14. hartmandm

    hartmandm Moderator Platinum Level Sponsor

    Not really relevant to the issue at hand, but for future folks looking at this thread, the solenoid to coil wire is white + green.

  15. 65beam

    65beam Bronze Level Sponsor

  16. puff4

    puff4 Gold Level Sponsor

    Tom, correct me if I’m wrong, but I believe the wire from the ignition switch will only power the white wire to the coil (via ballast) when the switch is in the “run” position, but -not- when it is in the “start” position. So, without a wire from the solenoid to the coil, whilst one is starting the car there would be no power to the coil, but upon releasing the switch to the “run” position it would then get power. Therefore, the car may start, but only once the switch is released.

    My understanding of the design is that essentially what happens is that the coil is powered by the solenoid (at full, un-ballasted, battery power) during the starting process, but then power is rapidly switched over to come from the ignition switch (and therefore at a ballasted level) once the key is released.

    This gives an extra bit of coil power during starting, to compensate for the draw-down on power by virtue of spinning the starter motor.

    So... although you say it’s a “bypass” wire that’s only needed in cold weather, I think, in fact, it’s needed at all times because without it the coil would not get power during the start phase (assuming I am correct that the ignition switch does not supply power to the white wire when in the “start” position).

    Correct, Tom?
    Last edited: Jun 30, 2019
  17. Tom H

    Tom H Platinum Level Sponsor

    65 Beam, Indeed, the white wire is the wire that carries power to the coil "when the switch is on". You can plainly see that white wire in the photo above carrying power to the ballast resistor. This white wire is the wire that loops through the tach, and comes from the ignition switch, not the solenoid. Also the stock wire from Ballast resistor to the coil is white / green as you state and as can be seen in the photo. The white / green wire that Mike refers to is the wire inside the black sleeve that is shown connected to the same coil terminal as the white green wire from the ballast resistor. That sleeved wire can be seen in the photo as it goes across the firewall just under the hood latch. That white / green wire goes to an extra terminal on the solenoid and applies full battery voltage directly to the coil (bypassing the ballast resistor) only while the starter is engaged. This is to provide a boost of voltage to the coil while cranking, especially for cold weather starts. This is the common factory setup for Series 5 Alpines shipped to the US. In an earlier post you noted that none of your Series 5 Alpines had this cold start circuit. Can we assume then, that the Series 5 in the photo above is not one of yours?

    Kevin, not quite. The Ignition switch continues to apply power, via the white wire, even when in the Start position. So even if the "cold start" wire is absent, the car will probably start. But if the "cold start" wire is in place the direct battery voltage coming from the solenoid simply bypasses the ballast resistor and carries full battery voltage to the coil. There is no "conflict" in this arrangement. Electric current always follows the path of least resistance, so while cranking, all the current and power to the coil follows the path of the bypass circuit and NOT thru the resistor. For this reason you will not see any revs indicated on the tach while cranking , because none of the coil current is going thru the white wire that loops thru the tach.

    Last edited: Jun 30, 2019
  18. puff4

    puff4 Gold Level Sponsor

    I should note that I ran into a problem once on an Alpine when the symptom was that it would start when the ignition key was in the start position, but would die as soon as the key was released... turned out to be a bad Lucar push connector on the ballast.
  19. 65beam

    65beam Bronze Level Sponsor

    Something to think about is how many cars have not had changes made to the wiring? It's will be 60 years on July 2 since the Alpine was introduced to the world. I have a few boxes of original wiring harnesses and I doubt that there are any that haven't had mods or wires replaced. Just because it was doesn't mean it's still that way. Don't the circuits just need to be wired correctly regardless of color used? I have bought and installed three wiring harness that were made in the U.K. I have found that there are several wires that aren't the same color coded wires as original. Especially the white wires. The most recent I bought for the RHD has yellow wires for the generator circuit instead of the brown wires. I have all the correct wiring but it's old and due to everything on the car being new or restored I chose not to use it. I didn't use the wiring that came with the RHD car because it was really butchered and brittle. Do you know where the correct color coded wires can be bought?
  20. Eleven

    Eleven Gold Level Sponsor

    Well guys, I thank you for your help.
    I put the old Lucas coil back in and wired in the ballast resistor. Still hard to start and lumpy when running. Played a bit with the timing but that didn't do anything. I believe the reality is that the engine is flat worn out given the low compression. Happened pretty quickly, last time I checked it was closer to 150ish. I will do it again to see if I missed anything but doubt it. Interestingly, it doesn't burn much oil but the oil gets black fast There is also, as mentioned above, a lot of air flow through the valve cover. Apparently this is indicative of blow by which makes sense.
    Sigh, someday I might actually get to enjoy the car but between the, diff needing replacement, the wheel/ hub replacement issue and now looking at a potential ring job, I am not optimistic. 10 years with this thing and have had probably a total of 3 months driving it. Guy down the block as a '63 T Bird. Going to look at is this afternoon. Maybe get something fun to actually drive.

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