Recently I have had a strain of new problems on my 94'. It all started with my truck over heating because of a jammed thermostat which caused the expansion tank to explode, so it sat for a while. With that fixed now a month later, the truck has a new odd problem. First off when starting it if you put it right into gear after starting it, it will quit, which is new, you have to wait like 3 seconds. Second there is a burnt plastic smell coming from somewhere in the front half of the truck. Third when running there is a odd groaning sound also coming from the front half that gets louder when you put into one of the drive gears and the brake is applied. This sound quiets as the RPMs increase almost immediately, there also is no power deficit. Also though it may be unrelated my tach has quit working. I am worried my truck may have seen its last trail, please help!

Thank you in advance...

 

1. Alternator is not charging battery, which makes tach read zero. Confirm by voltmeter across battery when running, should be like 13.8 - 14.2 volts. Alternator could be that smell. Also could be wires from battery, and large wires in the underhood fuse box. All those connection may need clean up with wire brush.

If alternator bad, suggest either used one from same type of Rover, or rebuild that one at local small alternator/starter shop. You can get a rebuilt from the store, forum users have 50% success rate with those things. New is pretty high.

There are three wires on the alternator - big one is the output, smaller is the "exciter" wire that supplies 12 volts to make magnetism, and little one that plugs in is the pulsed signal to the tach (which could be unplugged, but with the burnt smell, probably not).

2. Check fluid levels in tranny and oil, check for contamination. Radiator has oil cooler, tranny cooler, and plain old coolant. No mixing allowed. Overheat might also have been related to viscous fan clutch (should not spin free wheel), or clogged up radiator (yours is of an age and a type - brass & copper - where it can be rodded out).

3. Once power is stable, fuel pump, idle air control valve, and other things will work better. Of course this is based on what you have told us so far. How far have you driven the truck with tach out? If alternator is dead, battery won't last but maybe 120 - 200 miles, if that.

 

Honestly I could care less about the tach I am most certainly more worried and looking for ideas as to the source of the sound.

 

The tach not operating is usually the first indicator that the alternator has stopped working. So is your battery being charged properly? I was thinking burned smell could be alternator.

 

I will have to test it tomorrow because it has been storming since I got out of work here.
Also yesterday I took the alternator apart and cleaned it and it didn't change anything the brushes looked fine and everything... but nevertheless I will check the voltage tomorrow.

 

Well, since you got the truck running again, about how much has it been driven? A bad alternator won't charge the battery, and after several crank ups, and driving around town, with AC on, you'll kill what was left of the charge in the battery. On the other hand, if this it has been sitting and not being driven, battery might still have some charge.

Or it could be something else all together and your tach lead could be unplugged, or you could have a loose connector that the tach wire passes thru on the way to the dashboard.

Plastic burning smells are usuallly something related to electric insulation.