: Help on starter removal on a 1984 deville 4100

05-22-06, 01:52 AM
Hi Folks,

The starter solenoid on my 1984 Deville 4100 died this afternoon and I have to replace it. Underground garage and no tow truck is going to make it down there, besides I'd rather do it myself :-).

Problem seems to be that there is a "lower flywheel cover" that masks one of the starter bolts. This is going to, I think, require jacking up alternate sides (no ramps and 2 jackstands) to get the cover off to get at the starter.

I am sure I have all the tools and the good sense to disconnect the battery, but it is going to be fun under it with not a lot of clearance.

The book I have on the car (Haynes) seems to be pretty much useless (it is why I now know the starter is on the drivers side and not the opposite where it shows it). Sure glad the Caddy has a good jack!

Any suggestions, pointers or hints before I start on this would be greatly appreciated! Thanks much in advance!

Take care, BronzeDragon (keeper of the Bronze Dragon :-).

05-22-06, 08:05 AM
You might try getting a hammer and a friend.

Starting whacking on the starter with the hammer and have the person keep key on while you do it, very often you can get them to start.

In a GM starter, the ultra low resistance of the starter winding completes the circuit of the solenoid. These cars commonly have the venerable GM 5MT starter, which got revised (probably just renamed....) to the SD250 around 1990, and they had common problems with the armature fail, which would open up the solenoid ckt. So it won't click at all. If it clicks and doesn't start, then it is likely the solenoid, but no click, starter motor.

I think I have posted a detailed troubleshooting on the FWD forum, take a look there for a post from me and SD250.

05-22-06, 02:45 PM

Thanks VERY much for the response!

Looks like it is the starter rather than the solenoid :-(.

No clicks :-(.

I jacked it up again last night and weaseled under and I have voltage at the large terminal.

Jumpered from the large to the small terminal and all it does is spark. No click nor a click when the key is turned.

Not sure if this is going to be possible to do myself, thinking on it at the moment. The problem is getting it up enough to get under it and work.

No idea what it is going to take to remove that lower flywheel guard. I do have unkind thoughts about the designer who let it mask one of the bolts though, making all this necessary :-). Probably is not a big deal if one has a lift :-(.


I do realize I do need a decent manual for it, the Haynes I no longer trust. I'd hate to spend the day getting that guard loose only to discover I can't get it away enough to get at the starter. Really hard to see and work in what space I can get under there.

Thanks es 73, Bronze Dragon.

05-22-06, 02:53 PM
Do you have voltage (from that wire to ground) at the terminal that goes from the solenoid to the starter motor (you might see a braided fat wire, sometimes a brass post) when the key is turned? If you DO and no click/motor turning, then the motor is likey open.

Does someone have the FSM (any year) on the starter/solenoid test? I don't have my FSM handy. I think I did post it on the FWD or HT4100/4.5/4.9 forum. Look for posts by me, and SD250. It is detailed, you can fix.

I would drop starter if you can't get it going and troubleshoot it before you replace.

To test, You have to disconnect the fat wire from the battery to the solenoid to do this test. Else it will apply that power through the solenoid and spark city. Then apply +12v (from the key, just turn it) to the solenoid, and ground the fat braided wire/rope wire, the solenoid will now latch. If not, solenoid is bad. If does, likely ok. Now, measure from the motor wire (that you grounded) to ground, should be near 0 ohms on 200 ohm scale.

Basically the motor is the low resistance "ground" that make the solenoid latch up when the power is applied to it.

Make sure it isn't neutral start switch too. Turn key and shift through all gears (ebrake and foot brake applied!) if it starts, it might be neutral start switch.

05-22-06, 03:20 PM
Hi 4