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overdrive

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69tr

Jedi Trainee
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I Just got my 69 TR back on the road after a 2 year re-do. I took it out for a short shakedown ride today and, all and all, it ran pretty well.

The major thing that concerns me is that the overdrive does not engage. While I had it apart I replaced the seal on the plate where the actuator operates. I also replaced all of the enable (or by-pass) switches. Before I put everything back together I adjusted the OD lever by the instructions in the Bently manual. All of the switches are working correctly and the solenoid is operating.

Does anyone have suggestions?

Thanks, Pete
 
Oh cool, another Pete!

Maybe that OD lever is out of adjustment again. Sometimes new parts need readjusting not long after the 1st adjustment.
 
All I can tell you is my experience. After 3 shops "fixing" the overdrive in my 60 TR3A...and draining $500 out of the pocketbook...the overdrive still did not work. 4th shop took about a hour to properly adjust the lever properly. By then the poor adjsutment by the first 3 shops had burned out the
solenoid or relay. Finally...works great. Wish I had found shop #4 first...and had the $$ in my pockets! Gil
 
I went back to readjust the lever and now I am confused.

The Bentley manual says that the overdrive is engaged when the lever on the steering column is in the up position. When the lever is in the up position it takes power off of the solenoid (Yellow/purple wire). I thought that the solenoid had to have power to engage the OD.

It also says to align the lever on the opposite side of the transmission with a 3/16 rod with the OD in. I adjusted with the switch in the down position and the solenoid plunger pulled in.

Overdrive still will not engage. What am I doing wrong?

Thanks, Pete
 
Pete, I just read somewhere, maybe the Buckeye Triumph technical section or on the Quantum Mechanics tranny site, that the 3/16 rod adjustment does not always do the trick and can be off a hair and not allow the OD pump to clear.

About the OD switch lever position - Down is ON, Up is OFF. The manuals have this mixed up, including the owner's manuals.

Have you checked the tranny/OD oil level, or better still, have you drained the old gear oil, cleaned the OD filer, and refilled with 30W Non Detergent motor oil? Since you replaced the seal behind the Solenoid mounting bracket, I suppose you had to drain & fill. OD is sensitive to low oil level, too.
 
Simpson, thanks for clearing that up about the OD switch position. I though I was loosing it. (Well, I still might be loosing it)

I just changed the oil and filled with 30W non detergent. I took out both drain plugs to try to get all of the oil out. The car has not been run since I did that until yesterday.

I might contact Quantun Mechanics and see if they can give me any guidance.
 
Pete the clue is what you didnt do when you had the plate off.You didnt pull out the accumulator springs and piston,and the tiny valve that lets the oilpump put pressure into the chamber.One little speck of swarf and NO overdrive.The valve is the key.It can be done in the car,if the rear of the tranny is jacked up....
good luck
MD(mad dog)
 
I had a problem with my OD when I first installed it in my Spitifre. I had replaced the interrupter/actuator switch since i figure it was so old. I realized the switch wasn't actuating. I removed it and had to take the gasket washer off. Once re-installed without the gasket, it worked fine. Also double checked the od switch and it was fine too.
 
I am making some progress. I removed the tunnel cover to check the operating valve. I seemed OK. I used a squirt can to put oil thru it.

While checking the adjustment again, I saw that the solenoid did not seem to be operating fully or releasing fully. At this point I could get the car in OD by helping the actuator. (don't ask me how)I lubricated all the linkage. It worked a little better but not much. I removed the actuator arm and the grommet to check for a bind and the solenoid still did not act right.

At this point I unbolted the solenoid, held it in place by hand and applied power. The solenoid operated but the plunger would not drop out with power removed. I even removed the solenoid from the bracket and the plunger did not come out until I tapped on it a little.

Now I am cleaning and honing the cylinder and plunger to try it again. John at Quantum said it might be corrosion.

Sorry for the long post. I have a hard time expaining.

Pete
 
I checked the oil in the transmission and it was ok. I removed and cleaned the operating valve. I used a squirt can and pushed oil through it. I cleaned and honed the solenoid cylinder and plunger and they seem to be working fine.

The adjustment is my problem. It seems that the arm or solenoid is binding. No matter how I adjust, it will not operate correctly. Sometimes it will engage and not disengage I re adjust and it will not engage without help but will disengage. I have moved the linkage in and out.

I think my frustration level might have given me a brain block. I will try it again later today, maybe.
 
69tr

Don't feel bad I am right here with you

mine is an "A" type from Quantum worked for 300 miles or so

just pulled the tunnel and have the accumulator and associated bits setting here

on my desk ready to be reinstalled

then next will be a new solenoid


Please let me know your progress and I will do the same

Thx
 
Pete, it's OK if the linkage from the solenoid to the operating valve is a little stiff; the oil pressure on the operating valve should push it closed against a slight resistance from the seals.

I wonder if you aren't fighting multiple problems; the failure to release may be something else like the tiny drainback hole in the operating valve stem being plugged. Might be worth pulling it out to inspect.

As noted, the Bentley procedure doesn't always work. Basically, it assumes that the cam & stem for the operating valve never wear, but they do. Measuring the actual motion at the ball in the operating valve is a more reliable (although much more fussy) method of making the proper adjustment. Nelson's article on the Buckeye site gives more details (but Nelson was not the first to note the problem or it's solution).

I've also had problems with the adjustment moving. That solenoid really packs a wallop, which can cause an apparently tight connection between the lever and shaft to move just a bit every time. I wound up having to replace the lever to get it to hold adjustment.
 
Pete,

I now have my OD functioning

First I put the car on stands
removed everything to expose the trans
leaving the dr seat
slackened the clamp bolt at the linkage
lowered the set screw under the solenoid
( this procedure assumes that all of your electrics work)
start, put in 4
on the left side lever (where Bently says to insert the 3/16)
did not work
but I did find that the lever, that I thought had just a small amount of movement for and aft had much more movement forward, a spring affect
so whilst the car running @ 2500 r's I moved the lever forward and viola
OD,

At that point it was just a matter of putting some tension on the clamp that
the solenoid moves to make the adjustments and noting the position of the lever in relation to the casting around it
tweak and set, ride

From reading your post I would think that you might back out the set screw as that was my issue, not enough movement in the linkage to engage and disengage.

Hope this helps
like I said I know your pain
now on to the test drive tomorrow AM
 
I've been busy with other projects around the house and have not worked on the car for a couple days.

Randal, I removed the operating valve and cleaned it. I also used a squirt can to put oil through the valve. I am thinking about getting a new lever if I can find one.

Tony, I am pursuing the same idea that you had. I have the car on stands and also operated the lever and put in OD. When I get back to the car I am going to try some of the same things that you did. I am also playing with the stop adjustment. The thing that really worries me is that the overdrive might not disengage. I am concerned that it will remain engaged and I will put it in reverse and cause big damage.

Thanks to everyone for your input, Pete
 
69tr said:
I am thinking about getting a new lever if I can find one.
Click to expand...
I got mine at TRF. Looks like they still have them, P/N 502568 on sale for $3.93 until May 21.

Possibly I'm overly anal, but given the consequences of getting it wrong (as you've noted), I would (do) use the "ball lift" method rather than "by guess and by golly".

Note that getting the lower stop wrong can also have expensive consequences. If the solenoid plunger drops too far, it won't pick up when the solenoid is energized. That means it will not rise to the top and disengage the pull-in coil; which will quickly burn up (it draws about 20 amps). Not nearly as bad as breaking the sprag clutch of course, but still irritating. I added a fuse to the solenoid circuit so hopefully the fuse will blow before the solenoid burns up; if it happens again. (Grit inside the solenoid can have the same effect.)
 
The solenoid in my 1958 TR3A (marked LUCAS 1954) stopped working the day before I was to leave home here in Montreal for VTR in Portland, Oregon in 2000. So I removed the defective solenoid jury rigged a coat-hanger wire to manually pull up the lever arm that the solenoid usually pulls up. I ordered a new solenoid from a major US TR parts supplier in CA to be mailed to me in Portland. I put it in when I got to Portland and got home with no issues. A total of 7,250 miles. About 1,000 miles after I got home, the new one failed so I returned it. The replacement they sent me only lasted about 1,000 miles, so I took it apart and found gobs of white silicone used as a sealer or insulator in the top end under the rubber top cap. One of these gobs had come loose. It was the size of a pea and it was lodged between the blades of the contact switch in the top. I removed this "pea" and it's been fine since.

You never guess where or how the gremlins can get into your TR.
 
It shouldn't be that hard. I put the 3/16th rod in to align the lever on the right side of the transmission and the overdrive will engage. Pull the rod out and the out and the overdrive dis-engages. This is with the operating lever loose at the solenoid, the rear wheels on blocks and in 2nd gear with engine running. The solenoid seems to be pulling the alignment lever in but not far enough.

I guess the lever might be slipping when I tighten the clamping bolt. I will try it again later. Right now we are getting ready for my mother's 85th birthday party.

Frustration level rising.

Thanks, Pete
 
Once again when you have the accumulator apart there is a CRITICAL little check valve down in the bottom of it that must be clean!!!It stops the oil from going back into the oil pump(loss of pressure,heck, NO pressure)call it a bleed back valve, but dont ignore it.
And just in case you dont think that Don Elliott uses his over drive to the max,I can tell you about getting passed on the road to VTR 2000 in Or.The three of us were keeping up what we considered a good pace when the boys from Montreal passed us in their tr3's, like we all were down a cylinder or two...
MD(mad dog)
 
MD, I removed the solenoid bracket and replaced the gasket. I did not remove the accumulator. The OD was operating before I did this. To be honest I was afraid to remove the accumulator because I didn't know how much trouble I would get myself into.

If I don't have any luck otherwise should I pull the bracket off and remove the accumulator? Is this something that can be done with little risk? I don't want to get in over my head.

If I don't accomplish something soon I am going to order a solenoid and lever.

Thanks again, Pete
 
Pete,I have seen a lot of A types that stopped working for a little speck of swarf in this bleed-back valve.The A doesnt have the sophisticated filter system that the J has,and can get off line all too easily.Some A's had a little round magnetic ring in the filter housing that helped since swarf is a common and somewhat natural thing.
MD
 
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