Happy to report that the perpetual refurb is on the road after 10+ years. It goes pretty good & my wife is pleased with the A/C. Still have a few more details to wrap up and some bugs to work out. Like most others this car is far from stock - B-20 sourced from a '75 240 with electronic ignition, M-41 from an Amazon, etc. My questions might be better asked in different forums but there is much knowledge in the 444/544 group so I thought I'd start here.

The electronic ignition distributor that came with the engine baffles me as it seems to have a very wide centrifugal advance curve. This distributor has what seems to be a vacuum retard unit attached to it's side which is not being employed on my engine. When I set the timing for max advance (can't remember the specs - something like 38 deg @ greater than 3000rpm), the advance at idle is way late, like 10 deg after TDC and it won't run. If I set it close to the advance spec at idle, it will advance off the scale with increased RPM. I tried to balance it out between the two extremes which resulted in a barely-running idle. As I would increase the idle speed up from from like 400rpm to 800 rpm there is a substantial increase in the advance - I wasn't expecting any advance happening until 1200 rpm or so. I'm fairly certain that the distributor components are in decent working shape and assembled correctly. I believe the answer has to do with the theory of operation of the vacuum retarding distributor and whatever silliness that was employed by Volvo in the mid-70s to comply with emission standards. I'm afraid I am in the dark on this subject; any insight would be much appreciated.

The M-41 I installed was purchased as a pig-in-a-poke; the all to familiar "worked fine when removed" story. Thankfully there was no problem with the D-type other than a few leaky gaskets and a broken wire inside the solenoid that was easily repaired. But what wasn't obvious is a problem in the transmission; this gearbox doesn't like to go into 4th. The symptoms are that it seems like the throw is limited going from neutral into 4th, although the travel of the shift lever is the same as in 2nd and nothing is impeding it's travel. When shifting from 3rd into 4th it acts like there is enough inertia from the gear shifter to slide the internal parts into gear solidly, but it is reluctant to go all the way into 4th when shifting from neutral. It is even hesitant to engage 4th while sitting parked with the engine off. And sometimes while coasting down a hill in 4th it will want to pop out of gear. No strange noises and normal operation in 1-3 & reverse. Perhaps it is a bent shifter fork, perhaps a worn/missing spacer. Any experienced gearbox gurus want to weigh in?

Thanks for your time,

Joe in St Louis

Did you get/install the black box that comes with the '75 240 distributor?

Plug the vacuum line!
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George Downs Bartlesville, Oklahoma

Hi George,

Knowing it was a vacuum retard distributor I knew not to hook it up to a vacuum source, so it is operating strictly with centrifugal advance. Do you happen to have any specs for this dist? I pulled a part # off it yesterday;

JGFU 4 0237 002 002

It came with the metric B20F sourced from a 1975 240. I did not retain the fuel injection on this engine (actually it had been removed prior to me getting it), opting to mount a pair of HS-6 SUs that were on the B-18 that came with the PV.

No specs off the top of my head....
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George Downs Bartlesville, Oklahoma

Thanks for the replies. Interesting discussion on the 4th gear switch for OD (yes, the OD is working just fine). Something I'll need to look into.

And yes, the tunnel was replaced. But if I recall correctly I cut the original tunnel off aft of the hole for the gear shifter.

I do believe the shifter is going full travel. It pulls way back to the same position in both 2nd & 4th, and there is no problem with going into 2nd.

Appreciate the comments!

Joe in St Louis

I tend to think of my 122 (although I did put a D type in a 444 a long time ago.

Did you keep the long shift lever or change to short shifter? I'm not familiar with the mechanics of the short shifter, so what you're experiencing could be a function of the short shifter linkage. An 1800 person will know more.

On one M41 I rebuilt, I had a problem where the trans would "drop" out of 3rd gear, which is different due to the weight of the lever, but I attribute it to the fact that I didn't replace the circular tensioner rings that apply outward pressure to the 3 "dogs" that are part of the shift/synchro assembly. It would only happen when backing off the gas in 3 when under load, and not all the time.

I asked if you had opened the box up and replaced the top cover gasket because it's possible that the tolerances, and a tight cover might be a reason that the 4th gear lockout lever would have difficulty engaging the switch and it's heavy duty spring. Unlikely I guess. Also, I don't know if the piece on the shifter shaft is located with a set screw or a spring pin. Wear or looseness there could cause binding.

What you describe as limited throw from neutral to 4th is that piece on the shifter shaft engaging the switch as/before you get into 4th.

Re-reading your post, I'm feeling confident that it's lockout switch related.

If you unscrew it and the problem goes away that'll kinda confirm it. If the switch is too long, and projects further down than it should, or there is no washer btw it and the cover (is there sposed to be one?), that would make for more resistence as well. You can look at a picture of the switch here:

http://www.cvi-automotive.se/en/articles/2.10412.43379/inhibitor-switch-overdrive

Thanks for your replies Danny. I did retain the long shifter on my transmission, but I do not have a limited throw; it seems to travel just as far from N to 4th as it does from N - 2nd. You may be on to something with the problem being related to the switch. Can't remember the details of why it was missing, but I do remember drilling & tapping a hole in the cover for the 4th gear switch.

Can't remember - must be loosing my mind - blame it on senility or brain concussions. I gotta hurry up & fix this thing before they take away my drivers' license!

Appreciate your helpful insight,

Joe in St Louis

You didn't say whether the OD worked. Or maybe you alluded that it did.

First thing I'd suspect from your description is the 4th gear lockout switch in the top cover. It has a very heavy spring. You might remove the switch and see if it shifts easily into 4th. You might be able to clean/lubricate the switch mechanism if dirt or wear is making it difficult to engage.

IIRC this switch is actuated by a part on the shifter shaft that is located and held in place by a setscrew into the shifter shaft. The actuating piece has a chamfered leading edge which pushes the ball on the bottom of the switch which is held down by aforementioned powerful spring. Misalignment or loose attachment could cause binding or non op.

Pull the switch and try shifting into 4th - you can do this from under the car with some difficulty without removing the transmission.

Did you install a new top cover gasket? Are all 3 detent balls and springs in place? Is the cover snugly fastened?

My first thought was something simpler. As a new tunnel has been fitted I wondered if when the lever went to the 4th gear position it hit the edge of the hole in the tunnel. If it did go into gear it might only take a bump for it to be knocked back out again. Easy to check on the road with the gaiter removed.