Rear disk brakes conversion

We know that this has been done badly numerous times, and done well fewer times. Who can tell us the difference?

Sheared distributor gear

I replaced the distributor, but the distributor gear kept on turning even though the distributor stopped -- broke both tabs off the gear. My problem is this: how does the gear come out? Through the top? Should I try to drill, tap and easy-out the gear? Do I need to rotate the shaft? Or do I have to pull the pan and it get out somehow from the inside? Whatever it is doesn't seem easy. It's a really tight squeeze if it comes out the top and a lot of work if it drops out the bottom.
Glen Collins

Not so simple a problem. The gear pulls out the top; you'll have to find some way to grab it. It is case hardened and will wear out your drill bits and break off your easy-out. I would also wonder if the bushing under the gear sustained damage, and where the remains of the tabs went.

If you chose to proceed without pulling the motor for further inspection, there is some chance that you will be able to extract the gear without pulling the pan. Make a drawing or otherwise mark the exact orientation of the gear as it sits installed (there's enough left of the tabs to see where they were, I hope). It will twist as it comes up -- note its orientation at the point where is disengages the drive gear on the cam as it comes up. Not only does the gear have to go back in the same way, but its shaft will have to mate with the oil pump as it goes back in. No turning the motor with the gear out!

Removing brake drums

The special tool is a regular wheel puller. The three legs bolt on to the lugs on the wheel and the central screw presses against the end of the axle. Simply tightening the screw is not enough -- the trick is to smack it very hard with a heavy hammer, like you were trying to drive the screw into the axle. After a few repeated tightenings and smackings, the drum will pop loose.

Expert Opinion:

Additionally, replace the castle nut upside down on the axle before hammering -- this will prevent mushrooming the end of the axle.

Change the condensor. Other than that, no sensible clue. Has anyone else had this problem and fixed it?

Checking a coil

• How can I check continuity (or ohms) of each circuit? How many ohms will the secondary show? Will resistance be so high it simply shows up as open?
• Is there some other way to check a coil?
• Where can I get another coil if needed?

As you say, the 12V supply is in the back of the coil in the armored cable, where it is not accessible. The "negative" terminal (a misnomer in common usage) is accessible and connects to the points and condensor, and the high-voltage lead connects to the distributor cap. The coil's case is the ground.

Rather than check resistance, first check for voltage at the "negative" terminal with the ignition in "run" position. With the points open, you should read some low positive voltage; with points closed, you should read no voltage -- the terminal grounds through the points. If you get no voltage with the points open, disconnect the terminal and try again. If you still get no voltage, either the coil has gone open or is not being supplied with 12V through the cable (bad ignition switch?). If you do get voltage, there's a problem with the points, condensor or distributor insulator.

If the above checks reveal no fault, pull the high-voltage lead out of the distributor cap and hold it with a dry rag or other good insulator (potential exists to get a painful shock -- be careful!) so that the loose end is about 1/8" from a head bolt or other good, unpainted, ground. This should produce a fat spark upon cranking the motor. If it does, the problem is the distributor cap, rotor or plug wires. If not, you can be pretty sure the coil is bad.

The stock coil is sold as an assembly with the cable and ignition switch. This may still be available from Volvo (through GCP?), but it will not be inexpensive. There is no aftermarket replacement, and we'd recommend this only if originality is important to you. The usual fix is to mount a conventional coil (Bosch "blue" is good) and wire the 12V supply from the "switched" 12V terminal external to the cable on the ignition switch.

Weber conversion cold starts

Duane, it's baffling that pouring gas down the carb gets you started when your description of wet plugs would indicate an over-rich condition. Assuming your compression and ignition timing are good, I would first have a close look at the carb's float level and follow with jetting and tuning as described in the article in our Archive.

We have found it possible to flood our motor with this carburetor on occasion -- pulling the choke out opens the throttle a bit and causes the accelerator pump to send a squirt of raw gas down the intake. On a cold morning, it usually works well to let the engine crank for about two seconds before giving the choke a quick yank. If this doesn't work, turn off the ignition, wait about thirty seconds, and then try cranking with the choke all the way in and the throttle closed. When it fires a bit, "catch" it with the choke.

Supercharging 1800ES

In the D-Jet, as absolute manifold pressure decreases, more fuel is injected. If the MAP senses vacuum accurately, then why not a mild boost? The MAP is essentially a barometer that sends an electronic signal. Supercharging might be accomplished without complex air mass meters and fuel pressure regulators.

My ES has A/C, which is not a necessity in Seattle, so I already have a bracket for a supercharger and, more importantly on an 1800, room for something else under the hood when the A/C is removed. Pressurized air could be routed out in front of the radiator from the driver's side, through the old A/C radiator (modified to allow air to pass through the system ala an intercooler), into the stock air filter, and right back into the stock system.

I've been reading some of the Mazda Miata sites, as they seem to be the only ones now heavily into supercharging (aside from muscle cars). Would it be possible to request info from your readers about supercharging Volvos? If there is an experienced group out there, I'd like to hear what they have to say. Turbos are fine for the newer Volvos, but the older technology might suit me better.

After having given this a lot of thought and discussion, the short answer is "no, it won't work." The major problem is that the pressure sensor will only work on vacuum, not positive pressure, and we can think of no way to adapt it so it will work on pressure. The D-jet system is not adaptable to super- or turbocharging.

We still think supercharging has possibilities for a carbureted motor or possible for a K-jet, which matches fuel delivery to airflow, not manifold vacuum. Sorry!

Horn ring repair

Confession: our 122S's horns also go off when they feel like it, not when we feel like it (so they're not hooked up at the moment). Someone please help!

Disk brakes for 544

I think both modifications would be fairly simple to do, but we do not have any hands-on experience with it. Can someone provide the details (that would make a good article, too)?

Expert opinion:

I've converted my 544 to disk brakes; a pretty good explanation can be found at http://www.frontiernet.net/~pvpickup/fram.html, but it's not for the amateur! I've also installed dual circuit brakes, finally settling on a Mazda 626 M/C. A complete new mounting bracket is required, as is a bit of machining, some brake plumbing, and a proportioning valve. No volvo M/C is an obvious choice. I wouln't recommend either modification to anyone without a machine shop and expert help.

142E valve timing specs

Help please, readers and racers!

Wider wheels / V6 swap

Later model Volvo wheels use a different bolt circle size and will not fit. More information is found in the Tech Tips part of our Archives on this site. Has anyone out there done an engine swap using the GM narrow V6?

Expert opinion:

The lug diameter (4 1/2") and maximum offset (4") are the same as the early Ford Mustang -- I currently am running 14x7" Mustang wheels and am having custom 15x7s made by welding the Volvo hubs into stock 15x7" rims by a local specialist (that way I can fit the stock hubcaps). American Racing are a common US alloy fitment, and Cragar SS or Drag Lites will also fit.

Second Expert Opinion:

As you probably know, Ford rims have +1/2" positive offset (the seating suface of the wheel is 1/2" toward the outside from the center of the wheel), whereas Volvo 4 1/2" bolt circle wheels have about +1". I'm not sure what the 4" figure quoted refers to, but I assume it's "back spacing," the distance from the back of the rim to the seating surface, not a terribly useful number with changes in rim width. Stock PV, 1800S and 122S rims are 4.5" with 3.5" backspacing.

I have American Racing 6X15 (Ford), 3 1/2" backspacing, 1/2" + offset rims on my 544, which do work, but I've had to raise the car 1" to clear the tires, which are 195-65-15 (same diameter as 165-15).The width won't matter when the front wheels are turned under braking, either (especially with 2 200lb.+ people in the front seats), though the narrower rears would be OK. If I use 195-60-15 tires, I could lower the car 2" (!!), but I'd need overdrive (under consideration) to make up for the decreased tire diameter; the car's buzzy enough already. Maybe 185-70s would be OK if you could still get them. Having wider wheels made up with the proper offset seems to be the only (decent) solution. I also worry some about the wimpy rear axles with the extra tire hanging out.

On the other subject, I got a call a few years ago from a guy in Bakersfield who had a Buick V-6 in his 445 but wanted to buy a stock transmission tunnel to convert back to stock; I haven't heard from him since.

ES tachometer intermittent

Whichever model of tach your ES has, it senses current changes in the primary winding of the coil. Your problem would indicate a breakdown in the coil, condensor or distributor insulation if it's not the tach itself. You seem to have covered all this. Could your ignition switch have a resistive internal contact (does the switch get warm after prolonged running)? Readers, who's had a similar experience?

1800E sunroof

No clue. Can anyone help us out?

OD shifter

I've heard that you have to remodel the tranny tunnel to put in the short shifter overdrive. Is that true and is it easier to find an overdrive with the electric shifter on the steering column?

Yes, you would have to remodel the tunnel to fit the 1800-style remote shifter. However, you could also use your present top cover and shifter on the OD transmission, in which case no mods to the tunnel are necessary in an Amazon (not so the 444/544). All M41 transmissions used an electrically actuated OD, so you'll need a switch -- the "electric shifter" on the steering column is the most graceful solution if you can find one, but a toggle on the dash works too. Make sure you understand how the OD relay works before hooking this up. This is a common and most worthwhile mod -- good luck!

Expert opinion:

The shift plate for an OD tranny is different on the 122. There is a relay in the OD top (123GT or OD equipped) that is not on the M40 top. This is to prevent engaging OD in any gear other than 4th. With the column mounted OD switches becoming scarce, I suggest using the shift plate out of the '75 240 series that has the switch in the knob. This of course if you do the floor as I did on my 122.

Second expert opinion

The transmission cover for an M41 from 140 models with the long shifter has provision for the lockout switch (as well as a backup light switch; choose the right hole). Many are found with a plug in the hole for the OD switch. Using this cover, you won't need to modify the tunnel.

Mushrooming wheels

On a similar note, have you heard/ do you know of anyone who can do cross drilling on my stock 122S front rotors?
Tom Swartz

Tom, I can think of a number of reasons for not redrilling wheels, drums or hubs, but I don't have a good answer for your problem, nor do I know of where to have your rotors drilled. Tom is in the L.A. region. Readers?

Hardened valve seats

Yes, by all means have hardened seats installed when doing a valve job -- it will remove the old surfaces that were hardened by the leaded gas. See the Fuel Types article and the engine rebuilding articles for details.

Here's an additional hint: do not use bronze valve guides in a street engine. These are superior for racing applications in cars that run only a few thousand miles between rebuilds, but they cause rapid valve stem wear. The softer bronze material sheds microscopic particles that embed themselves in the hard valve stems. This eventally erases them much more quickly than in the usual "hard metal rubbing hard metal" scenario.

Expert opinion:

Your info about "not to use bronze guides for street engines" is totally wrong! Modern bronze guides, since '80s, are far superior and there's no wear. Bronze guides can take much more side load, too. This is important with hi-lift cams. Stock Volvo iron guides are prone to crack with stock lift. Also, it's wrong that bronze is softer material. Try it, take a file and file cast iron and then the bronze; bronze is twice as hard! That's why machine shops can't rebuild bronze guides, tools can't "thread" them.

Bronze guides were "whatever" in '60s and '70s. They didn't have right materials then. Not so for 20 years or so.

I've overhauled engines, built by me, after 150 000 hard miles and bronze guides were like new!

We came upon that info recently from a supposedly knowlegeable source, but we believe Topi is correct. We defer to his undoubted expertise.

Bucking ES

In spite of your rich-looking plugs, your symptoms still indicate (to me, anyway) a vacuum leak. This will cause a rich idle and rich running under some circumstances. Sounds backwards, but it's not -- let's just say the ECU gets confused. In the "little or no load" scenario you describe, the ECU cannot compensate for the leak at all (this is your highest manifold vacuum situation), and you get the "bucking" associated with an overly lean mixture, just as with a carburetted engine.

Two sources of such a leak are easily overlooked: 1) intake manifold not tight or leaking gasket, 2) PCV valve does not close at idle. Please don't just start replacing sensors -- it's not that hard to diagnose them accurately with a decent manual and a multimeter (but just about impossible to do from here!). I'll forward your question to Cameron.

Expert opinion:

Greetings from the Pacific Northwest!

Everything Phil mentions is on the mark. False air, or vacuum leaks can be tough to locate. I have a couple other thoughts; the trouble is that there are a few different things that can cause bucking in general. Assuming the ignition system has been safely ruled out (ignition points in good shape?), I would check the following, in this order:

1. The throttle position switch. This is the small square black box mounted on the outboard side of the forward end of the intake manifold. The cover is removable (early ones were secured with screws and later ones simply snap in place). Remove with care: the insides are delicate. (Also, don't unscrew the adjustment screws (upper and lower, there are only 2) at this point.)

   What can happen here is that as the contacts slide over the printed "circuit," carbon deposits can interrupt the signal to the ECU and result in bucking. Look for black arcs that follow the path of the 3 moving contacts. A pencil eraser can clean these off, but if the tracking is deep enough you'll need a new one. This switch goes for about $35. Easiest way to determine if this is the cause is to simply unplug the wiring harness from it and drive the car. It won't accelerate as well and you'll be running in "limp home" mode but if the bucking goes away, you will have immediately isolated the cause.

2. The base points. These are the points that are in the bottom of the distributor, held in place by two screws. These generally last for decades. Again, look for carbon between the contacts which open and close. Use a business card and slide it back and forth between the points to clean them. If they're pitted too much, they may not be salvageable. These run about $65.

3. Wiring to the injectors. I've had almost all of these fail over the last 4 years. Gently pull the rubber boots away from the connectors that plug into the tops of the injectors and look down into the white plastic housing that contains the wires and their terminals. There's a lot of temperature change in this location and the wires can give out. In my case, I had 2 or 3 strands of wire remaining: this was enough to signal the injectors at idle or at high revs but the vibration of the engine was just right between 3000 and 3500 rpms that I experienced SEVERE bucking.

4. Ground wires for the injectors. These are the wires attached to the rear of the intake manifold by a single screw. A poor connection or corrosion here can lead to symptoms described in (3) above.

My best advice would be to try these four things. Each can be accomplished without an ohmeter (an excellent investment, by the way) or a service manual. Please let me know what each of these inspections reveals.

Good luck on this one--

Update: problem resolved -- it was the throttle switch. Thanks, Cameron!

544 12V conversion

You will have to replace all the light bulbs, the battery and voltage regulator, for a start. I think the original starter and generator will be OK. As for the wiper and heater motors, their life is likely to be short, but merry -- see if you can get replacements soon! Anyone have a better idea out there?

Expert opinion:

I'm not quite an expert on this, since I've only done it to 445S and a 444, but nearly everything is the same.

Besides the lights, don't forget the turn signal flasher. You'll need to change to a 12V ignition coil/switch assy., or replace the whole thing with an aftermarket switch and 12V coil; after breaking off one too many keys, I'll recommend the latter. The starter will be OK, but the generator must be replaced along with the regulator, or an alternator conversion can be fitted. You'll be stunned at how well the starter works on 12V. Speaking of stunning, wait'll you hear the horns on 12V!!! The good news is that the rear wiper motor from a 145 or 245 will replace the 6V wiper motor with no alteration. I've used a GM blower motor in one 445 and the 444, but it required quite a bit of fitting; try to find a 12V 544 motor.

Here's the part I haven't done: the fuel gage. In my 12V 544, the fuel gage power terminal is the tie point for all switched power; I assume the same is true of the 6V 544, but it's not the case in the 444/445. I those cars, I put a 6V/10W zener diode between the 12V power and the + terminal of the gage; it works just fine. If the 6V 544 is the same as the 12V, you'll need to take all the leads off the + terminal and connect them together somewhere else (be careful!) and run the zener (in the reverse direction) from there to the gage terminal.

At least you won't have to worry about the sunroof motor or the power locks!

Painting an 1800

Sorry, but we don't know. Not only that, but we'd really like to know -- projects are in the works here, too. Who can help us all out?

200 HP P1800?

The "streetable" part is the trick -- a B20 with a big-bore kit, a cam, head work and a good exhaust system will make about 160 BHP for street use. I'd be interested to see what such a set-up might do with lowered compression and a Paxton supercharger. As for swapping in a "V" motor, it could probably be done if you can figure out how to make the headers clear the upper control arm mounts. The GM 60-degree V6 is an easy fit, but you'll never get as much power as you want out of one. My personal opinion is that 160 BHP in a 2500-pound car is enough fun for me -- readers?