I have a 1986 240 DL w/ 4 speed maunual transmission and the overdrive button. About 2 months ago the button for overdrive quit working. Over the phone estimates were quite high. I really like the car but it is 20 years old. What is the worst that can happen if I ignore the situation. I don't do a lot of highway driving. The car seems to run just fine otherwise. Any thoughts?
You'll spend a lot more in wasted fuel than to get the OD fixed, other than that you won't damage anything.
There's several things that commonly happen here, I can't imagine any of them costing more than a couple hundred bucks to have fixed, and most can be done by the average shadetree mechanic for pennies.
First thing to check is the wiring to the button, often it breaks right by the base of the stick under the rubber boot. A simple splice here will fix that.
4th gear switch fails, this is on the side of the transmission, as I recall a new one is about $25.Relay fails, new one is about $50, resoldering the circuit board inside it takes 10 minutes and will fix 99% of them.
Wire breaks off the solenoid on the overdrive under the car, a splice here will fix that.
That list covers at least 95% of the problems that crop up with these.
Thank you for your response and helpful information. I will try some of the simpler ideas and see what happens.
James Sweet wrote:
A few helps to Jame's suggestions.
If the dash light goes on and off with pushes of the button, the wiring at the shifter base, 4th gear switch and the relay are OK.
The connections to the solenoid on the left side of the Overdrive may not be tight and without broken wires inside the insulation where the terminal is crimped to the wire.
If the solenoid clicks when yoou remove and reattach the yellow wire on the solenoid when the dash light is on, and you still have no overdrive, the actuating pistons inside the overdrive have failed.
Replacing those O-rings is a Do It Yourself project. Similar but easier than changing a clutch.
If yo do it yourself, cost is close to $40 to $60 depending upon where you get the parts.
Duane
If I've got it right, at least you'll make the water pump work too hard, burn a LOT of fuel and the car will be a bit noisier.
I'm no expert; I keep locking myself out of mine :-(.
No war but class war. Sammy
Unless you have confirmed the cause, it may not be the button. Try replacing the relay first. I replaced 2 OD relays over the life of my
1984 240.The worst that will happen is that in certain situations then engine will use more gas and over the very long term wear out a bit faster because it's turning maybe 500 rpm too fast.
For what it is worth, over the phone diagnoses and estimates are in my experience not very accurate and usually priced high to cover the unknowns.
Check also to make sure the wires leading up to the OD button are not frayed or broken. They snake up through the shift lever and eventually can break.
I've had similar problems. The solution was cheap, but dirty and time consuming. The wires from the levertop switch share space in the gearlever with the lifting interlock for reverse. Each time you lift the collar to engage reverse, it chaffes the wires. You need a new length of wire and connectors. If the insulation has 3worn away you might also find a blown fuse. M.....
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