The latter occurs at the base of the gear lever, and should be investigated urgently as the feed is unfused and a break there has fried more than one wirning harness.Ģ. Common sources of power-feed failure are failure/wrong adjustment of the gearbox inhibitor switch, and (in rubber bumper models) a break in the wire going to the gear lever switch. Have the light on a long enough bit of wire to be observed while the car is being driven if need be. A simple idea is to link a test light in at the bullet connector where the solenoid joins the gearbox loom. Check there is power getting to the solenoid. If you find the solenoid is exerting sufficient load when activated, your next steps are:ġ. From memory, the normal load it exerts is around 13 lb. The LH solenoid requires less than 10 lb to actuate the hydraulics. The clutch pedal does not need to be dipped or accelerator pedal lifted off fully, there should be load To be me, if the o/d is operated correctly, it should change almost instantly >The OD worked fine for several years - engaged within several seconds<< See also posts on the other o/d thread here Testing on the bench only checks the solenoid at best. These can be anywhere in the connectors and switches, as well as where the solenoid picks up it's earth from the OD casing. Current should always be measured with the circuit connected and operated as it would be in the car so you can detect/eliminate bad connections anywhere in the circuit. The later LH-type solenoid takes about 1 amp with the engine running, about 800mA off just the battery. Refill the unit with ATF dexron and drive for a while then drain and refill with engine oil. Pull the gearbox drain plug and inspect it for the same sludge. While the sump is off pull and clean the pump one way ball valve.
The debris sounds like it is more likely from the gearbox rather than the OD unit. But any additional guidance/suggestions would be greatly appreciated. I assume I might test the solenoid as per Paul's instructions for the D type unit. I am seeking advice on my next steps here. I found about 1/8 inch of a greyish-silver paste like material ( like a thick paint or toothpaste) as well as a sprinkling of silver flakes (which may have come from the transmission). Worrisome is the debris found in the OD sump. I also reinspected the relief and pump body assemblies as per a John Twist video. The OD worked fine for several years - engaged within several seconds, did not slip and disengaged quickly.
I replaced the seal, cleaned the relief valve and pump body assemblies and checked the electrics. The rear oil seal was leaking leaving the unit and transmission with little oil. The unit was non functional when I bought the car. MG MGB Technical - Laycock overdrive I have a later Laycock OD out of a 76 roadster that stopped working recently.
0 kommentar(er)
