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  1. Ok. Its acting as a switch to earth instead of going through the gauge. But the separate circuits bit is not clear. In both methods both systems fail if there is no power from the delay unit. But yes you are right that they have separate outputs.
  2. My understanding of how this works is as follows. The numbers are made up for the explanation as i have nothing to measure. 12v from the cluster goes through the delay unit heater coil (1 ohm resistance). Then down to the sender (1 terminal). This connects to the bottom of the sensor resistor. The top of the sensor resistor connects to earth via the terminal (2nd terminal) and to the body. Assuming the sensor resistor is 19 ohms then total resistance is 19+1=20ohms. 12v/20=0.6amps. The 0.6amps doesn't create a lot of heat on the warning light delay contact so the light is open circuit and off. The wiper on the sensor resistor feeds through the 3rd terminal and to the fuel gauge. I will assume the gauge has a coil of 1 ohm resistance and then connects to earth at the cluster. So when the tank is full, the float is high, the wiper is near the earth end of the sensor resistor. Not much change on the delay unit (low current lamp off), the sender output is close to earth so the gauge reads high (full). When the tank is low, the float is low, the wiper is near the 12v end (from the delay unit). The circuit takes the path of lowest resistance so the 12v goes through the delay unit heater, then through the wiper to the gauge. So ignoring the minimal resistance of the sender resistor the resistance is 1+1=2ohms 12v/2 = 6amps. 6 amps through the delay unit makes the heater get hot and the bimetallic switch closes the circuit to the warning light (light comes on). Note the time delay while the heater warms the bimetallic strip - If the float rises again the heater goes off and the strip cools. So fuel slosh doesn't generate sufficient heat to warm the bimetallic strip. So from the above: If the delay unit goes open circuit (heater wire breaks) the warning light stays off but the gauge goes full. If there is no earth on the fuel sender. The gauge shows empty and the warning light still works. If there is a break in the sensor wire to the gauge. The gauge doesn't move and the warning light is always off. The warning light switch level is a vague level based on the resistance in the system so quite variable from vehicle to vehicle due to tolerances. I haven't looked at this for years but this is what i think happens. All 3 terminals are used.
  3. RobH might be right. I don't have a circuit in front of me. Many of the circuits don't show the sender internals so its hard to tell. I still think its in series. But i reiterate that its a delay unit not a relay. If you fit a relay the warning light would come on every time the sender float dropped. That's driving up hill and going round bends with about a quarter of a tank. Some sources may list it as a relay if they are not clear how it works or the typist thought it was misspelt. If you earth the signal to the gauge it should go full deflection.
  4. Its not a relay - its the delay unit. if memory serves:- You should be able to jump the input (from the sender) to the gauge and get the gauge working. There will be a bit of an offset on the gauge due to not having the heater in the circuit. I don't know how much that effects it but its probably not much. If the wire in the delay unit breaks then you will loose both indicators.
  5. Hi. My bracket that holds the fuse block doesn't align with the glove box. This is a RHD convertible. As far as i can tell my bracket has a another part welded on at the top that feels like it goes down the back, and has a stud that goes through the fire wall. Can someone confirm if thats correct. I haven't seen it in any pictures. The fixings to the glove box then end up about 50mm right of the glove box holes. Are there LHD and RHD brackets ? I don't think you can fit the bracket upside down. Any one let me know what they have. Because the stud aligns with the fire wall i cant adjust it. I will have to make an adaptor bar to support the back of the glove box. I have also discovered that my instrument lights seem to be earthed through the metal brackets. Not sure if thats right but if you are having electrical issues its something to be aware of - metal canned relays etc may need the case earthed.
  6. How are the guages not working? Stuck low, stuck at max, incorrect reading but changes as you would expect. incorrect reading that doesn't change. As Dave says the power is common across many gauges so unlikely to be the issue. Im no expert but:- The temp gauge suffers from:- No connection to the sensor (stuck cold), No power to the gauge (stuck cold), wrong sensor (changes with temperature but wrong values), Poor earth at the sensor (changes with temperature but wrong values), No earth at the sensor (stuck cold), short from gauge side of the sensor to earth (stuck hot). Fuel gauge. Much more complicated as it includes the warning lamp delay unit. However if the gauge moves when the ignition is turned on its probably either an earth issue, stuck sender or fault with the warning lamp delay unit.
  7. Melcoagain

    chassis holes

    The rimmers site show these with some sort of structure inside the rails but it doesn't seem that anything attaches to them. Could be for manufacturing purposes though it seems like over kill.
  8. I can't remember the TR7 wiring but i don't think there is a main fuse. I think the power actually goes to the starter solenoid and then the wires come from there to the ignition etc. So take a look at the solenoid connections. The solenoid doesn't need to work (it does to start the vehicle) its just where the wires come together. So if there is no connection at the solenoid nothing will work.
  9. If it is only due to the turnbuckle I can only assume that its an earth issue and that now the pod is touching the metal bracket its creating a circuit. Doesn't make any sense to me as there seems to be plenty of other conductive routes. If you have the rubber stops on the bracket this shouldn't happen. Might be worth putting some tape over the stop points to ensure they are insulated and see if that cures it. Since the pods are moving to different positions it may be that one has the lift arm fitted 180degrees out. Not sure how that affects the headlight but you don't know if someone tried to fix it by changing the wiring. Hope we are helping. Atleast we are sharing the pain.
  10. I had a weird issue when i replaced the main light switch. It doesn't sound the same as yours but be aware that the connector to the main switch can be fitted the wrong way round and give some peculiar combinations. Are both pods up at the same time or do you mean when both lights are lit the RHS is up and the LHS is down? Does the pod go up and down without stoping. If memory serves there is a 2 pole switch in the motor housing thats trigered in the up position to stop the motor. If this is faulty the motor keeps turning and goes back down. I think the other pole trigers on the down position. I believe these are pins on the motor connector as it feeds to the main light switch. If a couple of the terminals on the wiring connector are swaped you may have your problem. Im not the expert on this just trying to point you at a few areas to check.
  11. Anyone know where i can get the flocked seal strip that goes between the door trim panel and the window on a DHC. This is the inside one not the rubber one on the outside. After hunting around for ages i have come to the conclusion its sold by the bog suppliers as part of the trim panel. I don't want to but a whole panel just for the seal strip. Im missing the RHS one and it means the glass rattles a bit. Any alternatives or suggestions apreciated. Regards
  12. If we are speculating, they could be for seat belts. I don't recall them on mine.
  13. I think the SD1 rear springs would be to long. For info:- The inside of the tower is 190mm wide. My springs are 160 diameter so there should be 15mm clearance each side. On the front there is a reinforcing member that attaches to the inner wing. This is tapered but extends into the turret space by as much as 20mm - its dificult to compare to the spring. This is part of my problem. Incidently this doesn't apear in Rimmers online catalogue - or the rear one - and i couldn't see them in online pictures. Not sure if everyone has these. I also see that my 1st free coil is not concentric with the spring axis - looks like under load it will extend 5mm further. Also because the spring axis is not concentric to the strut the spring moves off centre when the wheel turns. The SD1 mount has an OD of 115mm so you can't fit a TR7 spring pad. I would have to change the mount aswell. I also noticed that the lower pan is hitting the corner of the turret. Must be on full lock. I have the front quite low at present - hence the short springs. The pan is wider than the spring. So to keep the cost down im going to grind 5mm off the front reinforcement. Fit the springs the other way up so the top is concentric and try and align the spring so its doesn't hit the reinforcement. If i cant find a simple way to make a spacer and raise the front about 10 mm i may cut the sides off the lower spring pan to clear the turret. The spacer has to ensure the spring doesn't move sideways off the pan. Other info that may be of use to others:- The SD1 mount has a bearing inside. It sits above the circumference of the mount so the top spring pad has a raised centre to match. I can see on one of mine there has been contact between the pad and the circumference. Since the circumference is fixed it has worn the pad, this would also make the steering heavy. I will fit a washer as a shim to ensure clearance. The SD1 top pad is angled to match the offset bottom. The SD1 strut is 51mm diameter - i measured it. So you can use the standard coil over conversion parts. You can also fit a TR7 spring and it would sit on the lower seat pan. The pan has a taper down to the strut so it would sit OK and probably about 10mm lower than the SD1 spring. Lengths would probably be wrong though. SD1 spring pad allows for 15" wheels. I can't tell if its the same height as a TR7 pad though. Cheers.
  14. Thanks David. Im not having much luck on this. I found some info on the TR7 springs:- 13.88" (350mm) free length, 7.5" (190mm) installed, 5.5" (142mm) OD. For uprated springs around 160lb/inch the free length should reduce to 10" (250mm). Can't find an internal diameter for the lower end though. The SD1 struts have an OD of 2.25" (need to check this) but thats means you can't use standard coil overs as they assume the spring internal diameter is 2.25". The standard TR7 strut should be the normal 2". The std TR7 top mount can cope with a spring with ID 3.75" with a new rubber. I assume the standard spring internal is 4.5". So does have to be changed for coil overs. My SD1 springs seem to have an OD of 6.25" (160mm) which is part of the problem. The other thing is that the SD1 lower pan is offset from the strut axis so it moves nearer the body when the wheels turn. My SD1 springs are supposedly 200Lb and only 8" long (200mm) free length. Interestingly im looking at using rear springs as the data i can find on the standard TR7 has 166lb/ft, 10.2" free, 8" mounted (but would be different on the front). Just need to find some diameter info. Otherwise this could be a cheap option. Im thinking I may cut the SD1 lower pan down, fit uprated TR7 springs (or rears) with new top seats and shim the bottom of the spring to get the height. Any info greatly apreciated.
  15. My 7 has SD1 front struts and custom springs. It looks like the springs are so big they rub on the inner wing panels under some conditions. I may need to rework these for smaller springs and the obvious route is to go back to the stock size even though i would use uprated springs. I may even consider a coil over set but those seem a lot smaller. Anyone got the outside diameter of the standard springs and free and loaded length. I can refit a standard top mount but need to asses how much i need to change on the lower spring platform.
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