78 300D ignition switch problems
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From: Prescott Valley, AZ
1978 300D
78 300D ignition switch problems
Two questions. I was going to use the search mode to see if this had been discussed, and I don't see where I can access this mode. I'm sure it's right in front of my face, but the screen is new to me and it takes me a while to sort out what's where. I'll take the ribbing for the bonehead syndrome along with the directions.
The technical question relates to the ignition switch on my daughter's 78 300D. It "feels" as though the switch does not work electrically sometimes. It's as if there is a fuel cutoff solenoid that starves the engine for fuel (haven't looked), and the glow plugs (and indiator light) do not always come on until the start mode is engaged, after start position is disengaged. Lately, the solenoid has been sticking, and I can't tell if it's a bad solenoid or a bad key switch due to the other symptoms.
It appears as if the position of the steering wheel has some effect on these symptoms as well. The question is, can the key switch be replaced, and can these functions be hardwired to switches. I see a few wires with single ended plugs on them, and it looks like there is a cam inside the key switch that may perform these auxiliary cutout functions. I suppose it stands to reason, because the engine has to shut down somehow when the key is turned off.
This car will not be a candidate for a restoration, although it's in good shape. Hot wires and a starter only key switch will work just as easily as replacing the steering column. We just want to get the car on the road as quickly as possible.
Thanks,
Allan
The technical question relates to the ignition switch on my daughter's 78 300D. It "feels" as though the switch does not work electrically sometimes. It's as if there is a fuel cutoff solenoid that starves the engine for fuel (haven't looked), and the glow plugs (and indiator light) do not always come on until the start mode is engaged, after start position is disengaged. Lately, the solenoid has been sticking, and I can't tell if it's a bad solenoid or a bad key switch due to the other symptoms.
It appears as if the position of the steering wheel has some effect on these symptoms as well. The question is, can the key switch be replaced, and can these functions be hardwired to switches. I see a few wires with single ended plugs on them, and it looks like there is a cam inside the key switch that may perform these auxiliary cutout functions. I suppose it stands to reason, because the engine has to shut down somehow when the key is turned off.
This car will not be a candidate for a restoration, although it's in good shape. Hot wires and a starter only key switch will work just as easily as replacing the steering column. We just want to get the car on the road as quickly as possible.
Thanks,
Allan
