Overdrive problem.

[Richard the old one]

I have noticed that my O/D has been reluctant to release a couple of times recently. It may be linked to being on a hot day and might be when the O/D has been engaged for a relatively long time. I am aware that if it does stay in that I must not reverse the car as serious damage may result. The Haynes manual indicates the problem could be cause by a "blocked control orifice" I do not think this is the problem because the O/D is currently working correctly. "Sticking cone clutch" If this is the problem should I just treat the o/d a bit more roughly? or "an internal fault" This does not help me.

I am looking for any suggestions.

[misterp]

Hi Richard,

I had a very similar issue (viewtopic.php?f=4&t=31278) and advise given to me on here (and the TR register) was to first things first..change the oil.

Secondly, I removed the overdrive 'sump' plate, and removed each of the plugs in turn, cleaned, replaced the O-rings and replaced.

BTW..an adjustable angle grinder pin spanner works well in getting the plugs out if your wondering.

Prior to my engine going pop...it was working like a dream and Im 99% sure that changing the oil would have fixed the issue on its own..more belt and braces approach if you change the O-rings as well.

Im sure you may have seen this already, but the Buckeye article is a great reference if your a hands on person...
http://www.buckeyetriumphs.org/technica ... 1/JOD1.htm
http://www.buckeyetriumphs.org/technica ... 2/JOD2.htm
http://www.buckeyetriumphs.org/technica ... 3/JOD3.htm
http://www.buckeyetriumphs.org/technica ... 4/JOD4.htm

Hope it helps.

[Jon Tilson]

I'd be looking at the solenoid O rings as my first port of call....

Pretty unusual though on a 1500....my spits on about 130 k miles, never touched and still sweet in and out as ever.

Long periods of indolence too. Its maybe a tad slow on the first time after the winter layup, but I have a policy of exercising it
pretty soon in the first drive...

Jonners

[Mahesh]

Just for reference I had a similar problem on my overdrive,

The switch on the gearstick was getting stuck in both directions,
easy to check it's just a make/brake contact, take switch off and
just pinch together for on, and release to disengage, just dont short out
on the gearknob or gearstick.

Or remove switch and connect to multimeter and test continuity in both
states.

[Richard the old one]

In response to Mehesh -I do not think it could be the gearstick switch as I am almost certain that at one point it stayed in overdrive when I changed down into second and the power to the solenoid would have been broken by the gearbox overdrive interlock switch as soon as I changed into second as the interlock is in series with the gearstick switch.

In response to misterp - My O/D works perfectly most of the time so it is somewhat different from your problem but many thanks for the Buckeye article.

In response to Jon - I must read up on taking out the solenoid if it plays up again.

[Mahesh]

I would also check the o/d switch on the gearbox, (in case of intermittent sticking)

The solenoid removal needs a very thin flat spanner, Overdrive services used one on mine,
and were able to change the solenoid from underneath the vehicle, I do believe they sell them,
but you may as well just borrow one for the number of times it may be used.

[Jon Tilson]

Drop the cross member and be pre armed with a special thin spanner....

Bit of a git of a job to be fair...

Jonners

[GTS290N]

I had the overdrive sticking only when very hot - in my case it was a faulty solenoid.

[Richard the old one]

I do have a spare o/d unit so I will have to get it out and see if I have a thin spanner to start with. It does not sound like an easy task to tackle without a pit or hoist.

The only other problem I have had over the years that I have been driving dolomite's with O/D was a gearbox inhibit switch that used to go open circuit when it got hot.

[Richard the old one]

I have checked that I have a thin spanner to get the solenoids out and have ordered new O rings for my spare solenoid but I have one question. When I read the Official Triumph repair manual and the Haynes manual there is no reference to draining the O/D before removing the solenoid. It was expecting to have to drain the o/d but if I do not have to do this it makes it a lot easier.

I have not yet crawled under my car to check on the access.

[Jon Tilson]

You might get a little dribble but most of the oil drains back into the box when the pump isn't working.

You may be able to get at it with the cross member in situ but I usually take them off to get access.

Jonners

[Richard the old one]

I have two spare O/D's. When I tried a thin spanner which I had on the first one it was easy to get at it and I was able to get the solenoid off. However I decided that I would take the solenoid off my other spare O/D as that was not fitted to a gearbox. This time however I could not get the spanner in as a thinner copper washer had been used to seal the joint between the solenoid and the body of the O/D. I thought all was not lost as I had seen that Moss sold a tool for removing the solenoid. When I got this home I did discover that it was slightly too large across the flats for my liking. Today I attempted to remove the solenoid on my car only to find that I could not get the tool in as there was insufficient clearance between the solenoid and the tunnel. I thought that I might be able to get the tool in if I dropped the rear end of the gearbox/O/D but unfortunately the sub-frame does not allow the gearbox/O/D to drop very much. At last nights get together with other triumph owners I was told that other triumph owners had removed solenoids by just grasping the body with a pair of mole grips as the body is quite strong so as a last resort I attempted this. It was a good job that I was watching what I was doing as the body started to move but the nut did not move. Luckily I stopped before I did any damage. The outcome is it is back to the drawing board to see if I can come up with some other way to get at the solenoid nut without having to drop the sub-frame or do some other major work.

In the mean time I am going to use the o/d a lot to see if this overcomes the problem of it sometimes being slow to disengage when the weather is very hot or the o/d has been engaged for relatively long period.

[80Sprint]

put your spanner on a grinder and it will fit..

[Richard the old one]

So simple why did I not think of that!! Many thanks for your help but I will have to see if I can get a spanner on the nut with the O/D fitted in the car.

[Richard the old one]

I have had another attempt to remove the solenoid but I have not been able to shift it as I have been attempting to do this with the car on axles stands, so it looks as if I will have to take it to the local garage. I have talked to one of the mechanics who suggested that I changed the gearbox/O/L oil first as he thought that might solve the problem. Unfortunately that did not solve the problem.

Currently I am tide up with a family problem but I will update everyone when I finally get the solenoid changed.