So I was driving to a gig last week, and not really paying attention, and as I pass a farmhouse I see a glimpse of a familiar blue shape.  I think I can smell a Jensen Healey if it’s in the same county.

Anyway, after a bit of haggling, JH #12281, or most of her, is in my driveway on my trailer. 1973 JH Mk I. “Blue J” will be scrapped after removal of the few good parts.

No engine or transmission (actually there is a transmission in the boot, but I don’t believe it actually goes with the car since it looks nothing like the Rootes transmission and has MOWOG stamped on it in a couple of places).

Quick research implies that it is an old MG Midget/Austin-Healey Sprite/Morris Minor transmission.  Nothing I can use.

Anyway, the rest of the car is exceedingly rusty. No floors to speak of, fenders are rusty in the usual spots, the bonnet is actually separated at the front. I was going to make the guy an offer for just the rear bumper (lots of surface rust but otherwise straight, including the stainless panel) and some electrical odds and ends, but decided just to bring the whole car home and remove everything of value, which isn’t a whole lot. The dash has one small crack and is otherwise good, the gauges all look good, the headlight pods are ok other than paint (they are the square bottom ones), the original rocker switches and turn signal and wiper switches are there, glovebox is good, and the seats are surprisingly good (just a separated seam on the driver’s seat) though they are black and I can’t use them in Ms. Jenavieve since she has a tan interior.

So, a couple of weekends removing stuff, and then off to the recycling yard she goes. If anyone is looking for Mk I “non-body” and “non-drivetrain” parts, ask since I may have something you can use. Otherwise I’ll just hang on to them for now.

Pertronix shipment arrived from Delta this afternoon. After supper, went out to the garage and spent about a half hour mapping out “before and after” diagrams of the ignition wiring. I had to remove the ballast resistor and account for all the wires… it wasn’t too bad actually. I was able to remove the ignition feed wire (white/slate if I remember right) from the ballast resistor and just pull it over to the coil and connect it directly to “coil+” (SIDE NOTE: I rebuilt my tach to RVC standards with the Spiyda kit a while back, so I don’t have to worry about the infamous “my tach doesn’t work with Pertronix” issue).

This done, the old coil and ballast resistor were removed, and the Pertronix Flamethrower coil was installed. I had to wrap a few layers of rubber tape around it to get it to fit snug in the old coil bracket… I’ll find a more elegant solution later.

Then, I just taped and tied off the other wires for now since they aren’t being used for anything (I also installed a gear reduction starter last summer so my direct feed to the coil from the starter relay is nonfunctional… both ends of the white/yellow wire are disconnected), Connected the tach feed to “coil-” and considered the coil done.

Moving on, I turned the engine to TDC, pulled the distributor cap, and noted which terminal the rotor was pointing at, double checked the other end of the wire, and it was indeed #1. Numbered the plug end of the wires, and removed one at a time and installed them on the new Pertronix cap in the relevant positions. That done, and after a quick trip to O’Reillys to pick up a new coil wire (the Pertronix coil uses a regular push on connector while the old Lucas coil used a screw on) I was ready to start on the distributor. Unplugged the remaining wire (again not being used in the new system, the other end is tied off at the coil end), removed the retaining nut, and pulled the old Lucas distributor. Noted the position of the rotor, aligned the Pertronix rotor in roughly the same spot, transferred the mounting plate over from old to new, and installed the new distributor… just had to wiggle the rotor a little to get the shaft to seat in the oil pump housing. Tightened everything up, reinstalled the cap, pulled the plugs and gapped them to .035″, reinstalled them and commected the wires, connected the red and black wires from the distributor to the coil, and figured it was worth a try at this point since I knew the timing had to be at least close.

Connected the timing light, said a little prayer, and turned the ignition key. And… she started right up. Wow. I wasn’t expecting that. A little rough, but running. Checking the timing light, she was about 5 degrees ATDC, so I loosened up the distributor and got her set to about 14 degrees BTDC at about 1100 RPM idle. And, after tidying up a bit, took her for a drive for about 20 minutes, hammering her pretty hard, and not a single bit of hesitation. She’s never run like this.

So, after all of this, I just should have listened to everyone who said “ditch the points and go electronic”. I would have saved myself about a month of hassle, and the conversion was actually pretty painless. Of course, all the other stuff like carbs, plugs, air filter, etc. is now checked over so in hindsight it probably was a good thing that I went through all this troubleshooting.

Tomorrow, I’ll go back in and route the wires properly and figure out what to do with all the extra wiring that isn’t being used any more. And come up with a better way to mount the coil. Just happy to have Ms. Jenavieve running like she should again.

Did a few more “just because” things last night just to further rule things out.

Pulled the filter element out (K&N element in the stock “muffler”), cleaned it, reoiled it, and reassembled. It wasn’t that dirty, and it had no effect as I suspected. I figured if it was too restrictive it could cause a rich condition, but no change.

Played with the Strombergs for a while. I didn’t adjust anything other than the idle speed since they were just balanced, but I did read up on their operation and ran a couple of tests to see what they were doing. I did the test where you lift the piston slightly and the idle came up just a little and then slowed right back down, so that seems to be good. I did notice several references to the piston having resistance on the up stroke but falling quickly with a “click”. Well, mine are definitely not clicking, but they do seem to drop fairly quickly. I’m not sure if that’s an issue or not.

Also (side note) I finally installed the replacement interior light I bought from Delta over a year ago… the reason I never got to it was because when I had the car disassembled for the repaint, I had left the driver side door switch hanging inside the hinge cavity when I removed the door, and completely forgot about it when I reinstalled the door, so it’s just been hanging in there for the last 16 months. Oops. Last night I removed the door, fished the switch out, and reinstalled the door and switch properly. Fortunately I didn’t have too much trouble getting the door to line back up, got it on the second adjustment.

Waiting for the mail to get here with my Delta package…

Just a little more info:

Took her out for a drive last night, got her warmed up good, brought her back and checked the damper oil again. The dampers still move nice and slow at temperature, so I think I can rule them out.

Also finally got around to pulling the plugs again (they look fine, no difference from one to the next) and did a compression check. Front to back: 120/120/120/125. Not exactly great but not surprising (the engine does have 98,000 miles on it), but more importantly no discrepancies between the cylinders to speak of.

Called Delta yesterday and ordered a Pertronix distributor and Pertronix coil. Crossing my fingers that that will solve the issue. I’ll be really ticked if it doesn’t, because I am running out of ideas…

Here’s where I’m at. Still no joy.

Hooked up a Mityvac at various places (not much to check since most of the vacuum lines are capped off now). Brake booster holds vacuum nice for at least 10 minutes, figured that was long enough for a test. When I connected the Mityvac to the main manifold port, the gauge bounced all over, which according to what I could find indicates a weak or broken valve spring. Very possible, but I don’t think that’s the cause of my issue.

Used a can of spray carb cleaner to try to search out vacuum leaks around the carbs. None that I could find.

Double checked the oil in the Strombergs. Definitely full, and the plungers seem to move very slowly like they should. I still wonder if heavier weight oil might make a difference (I just used the same 20w50 that goes in Ms. Jenavieve’s crankcase) but I have a hard time believing that this is the issue since this is the same oil I’ve always used.

I also, when I had her out this weekend, experimented with different choke settings while driving (when I came to a stop, I would pull the choke a little bit before taking off).   Other than raising the idle, it didn’t seem to make any difference, I still had the hesitation and backfire.  So I really don’t think it’s an issue of being too lean under those circumstances.  If anything, I think it’s too rich which takes me back to ignition…

I still haven’t done a compression test, but I don’t think that is going to solve anything (other than to point out other unrelated issues). I guess I’m at the point where I call Delta and order the Pertronix distributor and coil.

Spent quite a bit of time trying to track down Ms. Jenavieve’s misfire issue. After doing all of this, it still remains. To recap: she starts, idles, and mostly runs fine under most circumstances, but once warmed up, when accelerating from an idle after a stop, she misfires and backfires once or twice. Then, she’s fine till the next stop, and then it happens again. I can not reproduce this at speed (when cruising, I can stomp on the accelerator and she reacts like she should without any misfires). It only happens when accelerating after she’s been idling for a few seconds or more.

Here’s what I’ve done so far:

Carbs were balanced at the Jensen East meet courtesy of Ron Mau and Brett Gibson. Didn’t seem to affect anything.

Screwed down temperature compensators. No change.

Took distributor out, cleaned it up inside and out, relubricated the wick, inspected points (seemed to be fine). Reinstalled distributor, set timing to about 5 degrees BTDC. Seems to advance fine when blipping the throttle. However, the problem persists.

Properly gapped and installed new NGK plugs. Old plugs looked ok. No change.

Removed timing belt cover, disconnected coil, manually turned engine to TDC. Everything lines up as it should: 110/110 on the cams.

Removed bypass valves, cut and installed full face gasket. No change.

I then removed most of the vacuum hoses, removed the vacuum switch, and capped all ports.  Here’s a before and after view, using Mark Rosenbaum’s diagram, which I edited a bit for the “after” diagram:

Original routing:

After removal and capping (caps are shown in red, I also capped the vacuum retard port on the distributor which isn’t in the diagram):

The only vacuum lines in place now are the canister purge line and then T’d to the carbs (the pink line in the diagram). Obviously, the choke connector is still there as is the dark blue line to the fuel tank. All light blue lines are gone, the vacuum switch is gone, and the line to the distributor vacuum retard line is gone. Caps installed on the front carb throttle bypass port, the two rear carb ports, and the port on the intake manifold that was feeding the green lines to the vacuum switch and the vacuum retard on the distributor. Then, reset the ignition timing to approximately 12 degrees BTDC, reset the idle to about 1000 RPM, and it advances to just over 30 degrees at higher RPMs (I couldn’t see the tach and the timing mark at the same time, so I’m guessing I was at about 3000 RPM).

Whew.

Yet, the problem persists. I’m running out of ideas. I really think it’s an ignition issue, and my next step was to talk to Mike at Delta about a Pertronix distributor and coil. I know it’s a good idea, but I hate to go through the expense and time if it’s not going to solve this issue. Anyone?

Well, I just caused myself an afternoon of work (hopefully that’s all it will take). Those of you who were at the Jensen East meet might remember that Ms. Jenavieve had an odd running issue which we looked at while at the picnic: she started and ran just fine, but after she was warmed up she would miss and backfire a few times when accelerating from idle after running at speed for any length of time. Once she got over 2500RPM or so, then she would be fine until the next stop. So, I started thinking about what might have changed to cause this, and remembered that I had cleaned up the engine compartment while at the car wash right before we left for Rhinebeck. Figured it was worth a look inside the distributor, so I popped the cap and sure enough there was a little oily water in there. “My bad #1″… don’t ever wash in there without covering the distributor, it’s not exactly watertight.

So, after removing all the airbox stuff to get at it better, I sprayed some electronics cleaner into the distributor as best I could (not like you can see into it without a mirror), blew it out with compressed air, and cleaned up the cap and put it back together. After I did all this, I decided to check the timing, so hooked up the timing light and it was way too far advanced. I then loosened up the distributor clamp to adjust the timing, and while I was doing that I thought “I should screw down the temperature compensators on the Strombergs like Brett suggested”. So, I took them off, cleaned them up, screwed them down, put them back on, and went to start her up to see if it did anything, good or bad.

This was “my bad #2”. If you remember, I had loosened the distributor clamp a few minutes before. Oops. Of course she started, ran for about 2 seconds, and quit. Crap. So I went back under the bonnet and the distributor had pushed out about a half inch. At that point I decided it was too late in the evening and I was already making bad decisions, so this afternoon I will try to undo the damage I did. I guess the good news at this point is that I might as well take the distributor out all the way and clean it up good and check the points and such before I wrestle it back into place. Not what I had planned, but you know how it goes…