Working on the SM

Also, check the condition of your window switches. Since the switch itself carries the full current of the window motor, a new set of window switches will work wonders. The switches are essentially the same as a Peugeot 504, so they are available if you don't mind the slightly different graphic on the switch.


On my SM the windows were vert slow and required a push both up and down , a check with the multi meter reveled very low voltage .
My solution was to fit twin relays in the back of the engine bay with the power supply coming directly from the battery and using the SM window switch to trigger the relays.
Windows mow move by themselves at an acceptable speed.
 
OK I can see motor terminals so I will check motor voltage. You have reminded me that I have seen pictures of window switches in the SM Club de France Magazine with relays fitted on the back.

Cheers, Ken
 
Re the window switches, ones from a late CX or XM will fit, I replaced mine a long time ago. Also if they’re cracked it’s definitely worth replacing the plastic gearwheels with brass.

But don’t expect too much, the windows are just slow by modern standards. I often think there might be an electronics fix that would help if a higher voltage (like 18V) could be applied to the window motors for the first couple of seconds to speed things up without burning anything out.
 
Well I went down to try to measure some motor voltages during use but I couldn't get any sensible figures only 100s of millivolts. I think the terminals are so dirty I can't get a good connection. Anyway with the giggling of the connectors, the motor has gone from no go without help to running about the same speed as the other side ie sluggish. And they both go much better with the engine running and the alternator putting out 14 volts.

So I think I will put the door card back on and leave more extensive work for round 2.

The SM will be ready to go to Cit-in now, it just needs a wash before I go.

Cheers, Ken
 
Is it possible to spray the mechanism of the switch with circuit board cleaner? This approach works for me on those orange and green 'Sanor' relays on the CX. I must admit I have not yet tried it on the window winder switches. I intend to give it a go now!
 
I need to find out where I can find two of these relay boards. My car has the white switches.

Cheers, Ken

window winder switches relay photo small.jpg
 
Thanks Chris,

I will try to find the boards first as this will probably save me having to work out the circuits and then debug them like I did with the 2 speed radiator cooling fan retro fit jobbie I designed. I am presuming that all I will have to do is unplug the switch wires, replug them onto the pin in the same location on the bottom and then attach the board to the bottom of the switch.

I have sent and email to Genevieve at the SM Club to find out if she knows how I can get some.

Cheers, Ken
 
It has been over 2 years since I posted on this thread. There has been some interesting stuff happening that I could update you on, so here we go.

My electric windows are still working on their switches. I find they go a bit faster with the engine running and the alternator generating 14 volts so I will leave them as they are for now.

The Nulon G70 is working better and better in the gearbox to the stage where the second gear synchro feels like it is fully operation for normal use

The Lumenition system has been working reasonably well although when the engine gets quite hot, the idle goes off and it can be hard to start. Even running the coil amps straight of the alternator output didn't seem to help this situation much. I suppose when you are trying to start the engine, the ignition system is only running off the battery cranking voltage anyway.

The air-conditioning system is working well still with its initial gas charge but it does make the engine run hotter especially during summer in traffic. I think I have got this down to an acceptable level by arranging the fans to work in series mode all the time and then switch up to fast mode when the radiator temperature sensor triggers. I suppose I could beef this up a bit by getting the fans to run in fast mode when the compressor is active as well.

So the SM has been running OK through 2018 and 2019. We have been to Cit-in 2018, on a club outing to Stanthorpe and up to the Bunya Mountains during this time. There are some tuning issues that have become apparent. One is that the idle speed increases almost to 1500rpm when the engine is hot so I try not to drive it too much if I have to be stationary for a long time. Also the engine feels strong around town, on the highway it seems to have a huge flat spot around 3000 - 4000 rpm, right at the revs you want to start an overtaking move. In fact the engine seems to go better as you take your foot off the accelerator. It seems to be wanting a lot more ignition advance.

Then just as I was getting it ready to go to Cit-in 2020 for the 50 anniversary of the SM release, it decided not to start anymore. I initially suspected spark plugs because they have fouled up before. I changed the spark plugs and no change. Then I suspected ignition because my timing light was not flashing very regularly during starting attempts. So I changed the ignition back to points and spark seemed to be more regular but still no start. Then I checked the fuel rail and there was only a few drips of fuel and the pump was not able to prime the line. So had the Bosch pump failed after 47 years? There was also no fuel feeding the pump from the tank. Time to look at the tank outlets. All looked visually OK here but it was interesting to see a ligarex band on one side of the 12mm rubber joiner between the tank suction line and the nylon tube going to the pump. I decided to check out this joiner rubber a bit more closely and when I tried to remove it from the tank pipe, it just crumbled in my hand. There had obviously been a big hole in the bottom side of the joiner rubber and the pump had been sucking air. I found some 7/16 inch fuel pipe at Repco and replaced it, but the pump would still not prime until I disconnected the high pressure line heading up to the engine. No trouble staring the engine now, problem solved and maybe the petrol smell problem as well.

After reading Jerry Hathaway's article about reconditioning the SM Distributor, I decided to continue with working up the points ignition system so I had a choice of either Lumenition or points in the future. The newer style points cassette allow the points gap to be adjusted while the engine is running using a 3mm allen key through two holes drilled though the centre of the capacitor holder.

With some trepidation, I went over to son Chris's place and used his drill press to drill some 4mm holes. When I got home I put the distributor back together but I couldn't get my allen key in because the air filter was in the way. I lifted the distributor out and rotated it one cog on the layshaft so I could clear the air filter. I set the dwell up on both Bank A and Bank B points and then set the timing so that cylinder 1 of Bank A was firing at TDC or PMH as it is on the flywheel. Then I swapped the timing light to cylinder 6 and trimmed the dwell on Bank B points so that Cylinder 6 was firing on its TDC mark on the flywheel. Then I tried to set the timing to 22 degrees at 2000 rpm but I could only achieve about 20 degrees and still have the engine startable and idle speed reasonable despite playing with the advance spring tension. This is the smoothest I have ever heard or felt the engine run though.

It would appear that soon after I bought the car, the diaphram in the vacuum retard capsule failed. I have deduced that this capsule was fitted to drag the timing back 10 degrees when the engine is in overrun or at idle or when trying to start it. As soon as the throttle is advanced, the vacuum capsule in connected to the air cleaner intake pipe and it loses its vacuum source. It is very hard to start an engine with more than 5 degrees advance as the firing of a cylinder only 10 degrees before TDC will almost stop the engine rotating.

So the current projects are:

1. To get a 10 degree retard working for starting, to stabilise the idle speed and to allow more advance to hopefully cure the flat spot on the highway,

2. Fit some speakers for the front occupants because a lot of the sound from the back speakers is absorbed by the front seats.

With the second project, the SM comes with three speakers ??? and I would like to use the SM style speaker grilles and I wondered if anyone have one of these they were not using that I could access for this project?

I hope I havn't bored you all to much with this post.

Cheers, Ken
 

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It appears you can only edit your posts for 5 minutes before they become uneditable.

Some more pictures that might be of interest. It would appear that if you want to fully remove the fuel tank cover, you have to disconnect the filler and breather pipes! There is also some headlight self levelling hydraulics buried in there too.

Cheers, Ken
 

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Does 123 do a dizzie for the SM yet. A programmable advance curve could allow for very easy starting (eg: no advance below 800rpm).

Are the speaker grills the same as Series 1 CX's ?

seeya,
Shane L.
 
Ken, that speaker grille looks very like those fitted to series 1 CX’s.
 
Hi Shane and Bruce,

I23 did produce a dizzy for the SM but it proved unreliable. I think they just get too hot under the bonnet for the system to stay stable, so it was withdrawn unfortunately.

The CX Wagon I have must be a Series 0, as it only has a series of holes in the vinyl for the sound from the speaker to struggle through. I did have a CX2400 C-matic back in 1990s and now you mention it, I remember that it had better speaker grilles in it. I suppose I should try to find one of those.

Cheers, Ken
 
Does 123 do a dizzie for the SM yet. A programmable advance curve could allow for very easy starting (eg: no advance below 800rpm).

Are the speaker grills the same as Series 1 CX's ?

seeya,
Shane L.
123 no longer makes a dizzy for the SM, but John Titus (me) makes an electronic ignition conversion. http://tinyurl.com/h4st65z I also have replacements for the weak advance spring, which restores idle stability - no advance below 800 rpm.
 
I made an edit to my post, but it doesn’t show. The edit said “any above Super”. I assume the wagon is the equivalent to a Super.
 
It sounds liek the SM's run hot ?? I wouldn't be messing around with the factory setup given it isn't an engine driven fan. See if you can fit an EL falcon fan assembly (or even radiator ) in there.... if those things can easily cool an XR8 (6litre v8 ?) towing caravans .... the little V6 should be a piece of cake. The falcon fans are so much more efficient with the very well designed housing around the fan. the falcon fan unit seems to be the "go to" replacement unit. In the testing people (not me... but if you do a google search) have found they move more air than most of the high priced fancy setups you can buy aftermarket ( only they are about $10bucks from your local wreckers). I have one wired in the the range rover here.... it fits almost perfectly. I just wired it in to run series/parallel using a CX temp switch and three CX 20amp relays.

seeya,
Shane L.
 
I am making slow progress with fitting some front speakers into the SM. With young Ken's help, we designed a box so the speakers could be attached to the B pillar, just in front of the bottom of the door. This will allow the treble from the tweeters to have an unimpeded route to the front passengers ears rather than it being swallowed up by the seats when coming from the rear seat speakers. I have the LHS one trial mounted so far and am working on panel work and carpet before getting the RHS one installed.

Also, I took the LHS seat out so I could take the cover off the centre console to get the heater tap working again. The velour covering of the seat back has always been loose around the edges so I decided that I should try to take the back off the seat and attempt a reglue job. All was going OK until I discovered that the handle that triggers the seat back to fold forward and the seat to slide forward so passengers can get in the back seat runs through the seat back panel. How do you remove this handle? It seems to be firmly held into the seat but has a small degree of loose play in most directions. Checking under the seat reveals a bearing mounted into the seat frame and secured by a circlip. There is also an almost circular spring steel covering over the outer part of the bearing that seems to cover a clip that fits into the bearing. I am thinking that this clip is holding the handle into the actuator rod that travels across from one side of the seat to the other. It seems to be set up so that it is easy to push the handle in and click it into place as the final step of seat assembly but to remove the handle would require removal of the spring steel cover and then the clip to allow free removal of the handle. Can anyone confirm this course of action or have a picture of a handle removed?

Cheers, Ken
Front Speaker Mounted LHS.jpg
Seat Control.jpg
Seat Control.jpg
 
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As replacements for the Plastic Holding Blocks, I purchased some White Pencil Erasors, and cut them to shape with a very sharp knife.
From the photo Ken, appears that you eat a lot of ice-cream.
All the Best
David
 
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