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YakkoWarner
Jedi Warrior
Offline
I'll start with the forward progress first:
If anyone remembers; at the beginning of the year I had this - beautifully zip-tie mounted gauges and loose lamps dangling everywhere...
By June I got to this point - still a horrible mess where the center section should be and loose lamps hanging out from the panel because the high-beam and alternator warning lamp holders can only be obtained as $20.00 assemblies with integrated bulbs, and would require cutting off the original bulb holders to use. I'm not inclined to chop up the factory harness (although someone already apparently took a weed-eater to the center section).
As of last weekend - this is where its at. I repurposed (without further modifying or damaging of the factory harness) a redundant seat belt warning lamp to become the overdrive selected indicator in the center panel. It was part of undamaged harness section but requires seats with the pressure sensors - my seats are from an earlier year without any sensors. I patched in a wire from the overdrive solenoid (using factory style bullet connectors) to that lamp. The custom solid brass lamp holders for the hi-beam, alternator warning and (now) overdrive selected indicator bulbs are actually old mobile home plumbing fittings that took a quick ride thru the lathe to turn them into a flush front flange. The bulb assemblies fit perfectly into the backside like they made for this (even though they weren't) and they are much more durable than the unobtainable factory plastic parts. They also fit perfectly into the existing panel openings with no modification needed. I just need to get some colored plastic to make lenses for them and I might redo the turn signal indicators the same way just to keep it all consistant.
I made a blanking plate where the original (and I don't have it) AM radio was supposed to be, and put the OD indicator, a second 12V outlet, clock and voltage gauge there. These cars didn't come with a voltage gauge which was always to me a shortcoming. I couldn't find an affordable genuine Smiths UK gauge from a different model car, so I went with something that looked close (and was the correct size) from the local parts store. The clock is an actual factory clock provided by one of the members here (THANKS!!!!!!) It was included in the 1976-1980 year cars, prior to 1976 no clock was provided.
At this point everything with the exception of the heater controls is functional (including all the backlights). I chose to use a factory headlight switch (same size) instead of the basic on/off switch for the map light. Now I can connect the map light to the first click connection, and then add some footwell lights on the second click connection. That way I get footwell lights without losing the original map light functionality (and again no modification to the hactory harness). The harness for the center section was already pretty chopped up by multiple previous owners but I've been using factory style bullet connectors for everything I changed which tie back into the undamaged main panel harness. The hazard lights wiring was just chopped out completely (I suspect someone 'harvested' the original 6 pin connector that is no available for purchase), so that wiring is not original style - but not visible either.
So much for going forwards - now the steep fall off the cliff in reverse......
I ordered the high pressure oil pressure gauge with the proper fitting to test the overdrive hydraulic pressure. Verify clean 20-50 oil in the transmission and level is topped up. Everything electrical works - put the gear selector in 4th and flip the switch, I get power at the solenoid (as confirmed by my nifty indicator LED shown above) and while undernearth hear a very audible click when it engages (the driveshaft is out so I can run everything and slide underneath without having the wheels spinning). I used a high-capacity amp meter to confirm the current draw. On the gauge the oil pressure immediately jumps up - to between 250 and 325 PSI. I get the 325 when cool, it drops off to 250 as the tranmission comes up to temp. It needs a bit over 400 to work, so now I know what my major malfunction is. Before I put all this in the car I replaced the o-rings on the pump, relief valve and solenoid body. I also cleaned/replaced the screens and filters - made sure I had the little balls in the right places. I had no way to test it before installation because it need to be turning at at least 1000 RPM to engage, and I have no way to do that outside of the car.
So at this point I'm assuming this is unrepairable outside of replacing the whole overdrive assembly for $2000 (and ripping the whole car back apart again). I'm not completely surprised that its borked - the thing sat for who knows how many decades before I got it and it may not have worked even when the car was still being driven. It was a dice roll to find out if it worked and I definately came up snake eyes on this one. Is there ANYTHING I can do/test while it is still in the car to figure out why the pressure is low, or is it just too far gone to troubleshoot at this point? Could the solenoid be weak and just not closing off enough - seems unlikely because if it were just weak the pressure should remain constant. Likewise for the relief valve - if it were an out of spec spring, shouldn't the pressure remain constant? Losing more pressure as the temp climbs says abnormal wear in my mind, since its losing more as the oil gets thinner. If it were an engine I'd say bearings going out, but the OD pump isn't part of the lubrication system that I know of.
Will I do more harm just disconnecting the electrical, and driving it as if there was no overdrive? I expect at some point in the future I will be looking at a rebuilt engine (since I have no real knowledge of the history on this one). Right now it runs nice and has good oil pressure but who knows how long it will remain that way? I was hoping having the OD transmission would extend the engine life since won't be spinning as hard. Maybe I should just live with it as as-is for now and consider whether any of that is worth dealing with later. I have a spare non-OD transmission, and I also have another condition-unknown OD tranmission sitting on the floor - but a whole engine/trans pull and replace process just to take another roll of the dice isn't really appealing to me right now.
There aren't any British car specalists in central Texas so its not like I can take it in anywhere to get a professional opinion....
If anyone remembers; at the beginning of the year I had this - beautifully zip-tie mounted gauges and loose lamps dangling everywhere...
By June I got to this point - still a horrible mess where the center section should be and loose lamps hanging out from the panel because the high-beam and alternator warning lamp holders can only be obtained as $20.00 assemblies with integrated bulbs, and would require cutting off the original bulb holders to use. I'm not inclined to chop up the factory harness (although someone already apparently took a weed-eater to the center section).
As of last weekend - this is where its at. I repurposed (without further modifying or damaging of the factory harness) a redundant seat belt warning lamp to become the overdrive selected indicator in the center panel. It was part of undamaged harness section but requires seats with the pressure sensors - my seats are from an earlier year without any sensors. I patched in a wire from the overdrive solenoid (using factory style bullet connectors) to that lamp. The custom solid brass lamp holders for the hi-beam, alternator warning and (now) overdrive selected indicator bulbs are actually old mobile home plumbing fittings that took a quick ride thru the lathe to turn them into a flush front flange. The bulb assemblies fit perfectly into the backside like they made for this (even though they weren't) and they are much more durable than the unobtainable factory plastic parts. They also fit perfectly into the existing panel openings with no modification needed. I just need to get some colored plastic to make lenses for them and I might redo the turn signal indicators the same way just to keep it all consistant.
I made a blanking plate where the original (and I don't have it) AM radio was supposed to be, and put the OD indicator, a second 12V outlet, clock and voltage gauge there. These cars didn't come with a voltage gauge which was always to me a shortcoming. I couldn't find an affordable genuine Smiths UK gauge from a different model car, so I went with something that looked close (and was the correct size) from the local parts store. The clock is an actual factory clock provided by one of the members here (THANKS!!!!!!) It was included in the 1976-1980 year cars, prior to 1976 no clock was provided.
At this point everything with the exception of the heater controls is functional (including all the backlights). I chose to use a factory headlight switch (same size) instead of the basic on/off switch for the map light. Now I can connect the map light to the first click connection, and then add some footwell lights on the second click connection. That way I get footwell lights without losing the original map light functionality (and again no modification to the hactory harness). The harness for the center section was already pretty chopped up by multiple previous owners but I've been using factory style bullet connectors for everything I changed which tie back into the undamaged main panel harness. The hazard lights wiring was just chopped out completely (I suspect someone 'harvested' the original 6 pin connector that is no available for purchase), so that wiring is not original style - but not visible either.
So much for going forwards - now the steep fall off the cliff in reverse......
I ordered the high pressure oil pressure gauge with the proper fitting to test the overdrive hydraulic pressure. Verify clean 20-50 oil in the transmission and level is topped up. Everything electrical works - put the gear selector in 4th and flip the switch, I get power at the solenoid (as confirmed by my nifty indicator LED shown above) and while undernearth hear a very audible click when it engages (the driveshaft is out so I can run everything and slide underneath without having the wheels spinning). I used a high-capacity amp meter to confirm the current draw. On the gauge the oil pressure immediately jumps up - to between 250 and 325 PSI. I get the 325 when cool, it drops off to 250 as the tranmission comes up to temp. It needs a bit over 400 to work, so now I know what my major malfunction is. Before I put all this in the car I replaced the o-rings on the pump, relief valve and solenoid body. I also cleaned/replaced the screens and filters - made sure I had the little balls in the right places. I had no way to test it before installation because it need to be turning at at least 1000 RPM to engage, and I have no way to do that outside of the car.
So at this point I'm assuming this is unrepairable outside of replacing the whole overdrive assembly for $2000 (and ripping the whole car back apart again). I'm not completely surprised that its borked - the thing sat for who knows how many decades before I got it and it may not have worked even when the car was still being driven. It was a dice roll to find out if it worked and I definately came up snake eyes on this one. Is there ANYTHING I can do/test while it is still in the car to figure out why the pressure is low, or is it just too far gone to troubleshoot at this point? Could the solenoid be weak and just not closing off enough - seems unlikely because if it were just weak the pressure should remain constant. Likewise for the relief valve - if it were an out of spec spring, shouldn't the pressure remain constant? Losing more pressure as the temp climbs says abnormal wear in my mind, since its losing more as the oil gets thinner. If it were an engine I'd say bearings going out, but the OD pump isn't part of the lubrication system that I know of.
Will I do more harm just disconnecting the electrical, and driving it as if there was no overdrive? I expect at some point in the future I will be looking at a rebuilt engine (since I have no real knowledge of the history on this one). Right now it runs nice and has good oil pressure but who knows how long it will remain that way? I was hoping having the OD transmission would extend the engine life since won't be spinning as hard. Maybe I should just live with it as as-is for now and consider whether any of that is worth dealing with later. I have a spare non-OD transmission, and I also have another condition-unknown OD tranmission sitting on the floor - but a whole engine/trans pull and replace process just to take another roll of the dice isn't really appealing to me right now.
There aren't any British car specalists in central Texas so its not like I can take it in anywhere to get a professional opinion....