Jump to content

Recommended Posts

6 hours ago, John McCormack said:

I'll keep that as an option thanks Ralph. The circuit should still be broken by the isolator switch when the box is out of 3rd or 4th. By my thinking there would need to be a power source between the isolator and the solenoid to keep the solenoid engaged electrically and there is no such source on that short wire to the solenoid.

I haven't take the tunnel off yet, just been working from underneath. If I need to I will check the wiring throughout as you suggest.

Maybe I am reading it wrong, but according to my wiring diagram the solenoid is operated directly from the relay, and the isolator switches only complete or break the relay operating circuit. If the yellow and green wire running from the relay on inside of battery box up and across the back of the instrument panel to the o/d switch touches earth anywhere it would earth out the relay operating circuit and engage the o/d permanently in all gears. Just saying, I know what the back of the dashboard looks like with masses of wiring running hither and thither.

Ralph

20210403_081323.jpg

Link to post
Share on other sites
Posted (edited)
4 hours ago, NCS_TR3A said:

John, you said you cleaned it out with WD40, was it quite rusty. Mines been in for years but it's clean inside, shiny. The seal looks like the one in the photo attached to the plunger. That is for the A type overdrive. 

Neil

Screenshot_20210403_080356.jpg

Thanks again Neil.

The solenoid appears clean inside but I flushed it out with wd40 to make sure.

The seal is long gone, I don't recall seeing one there for at least 10 years. I just googled images of the solenoid and it should have a seal as per your diagram. I can't see a seal listed separately.

I can get a new solenoid through the Australian Register for a very reasonable price. As this one has been used for at least a decade without the seal a new one is warranted.

Edited by John McCormack
Link to post
Share on other sites
3 hours ago, Ralph Whitaker said:

Maybe I am reading it wrong, but according to my wiring diagram the solenoid is operated directly from the relay, and the isolator switches only complete or break the relay operating circuit. If the yellow and green wire running from the relay on inside of battery box up and across the back of the instrument panel to the o/d switch touches earth anywhere it would earth out the relay operating circuit and engage the o/d permanently in all gears. Just saying, I know what the back of the dashboard looks like with masses of wiring running hither and thither.

Ralph

20210403_081323.jpg

Thanks Ralph. I'm not good at electrics but I think I see your point, and I should have checked the wiring diagram rather than rely on my failing memory.

I had forgotten that the switch and interlocks actually make the earth to complete the circuit. If it earths between the fuse box and dash switch the circuit will be made permanently.

Further, if it shorts between the switch and interlocks it will stay engaged whenever the switch is made. Obviously a danger if you leave the switch in the engaged position and select reverse.

Very valuable advice indeed.

Link to post
Share on other sites
On 4/2/2021 at 4:26 PM, NCS_TR3A said:

Rob, thanks and your memory is correct. I took the plate off today to check and have attached the photo that confirms the seal is on the inside. I thankful you posted this before I was ready to refit, a far easier job on the bench. I did follow the process of removing the bolts a bit at a time due to the spring that sits behind it. I do also note that the o ring I have from Moss is not quite the same shape as the one I took out. The old one is more of a square section and thre moss one is more a normal (circular) one. Need to get a new gasket before refiting but thanks for positing the correct method. 

Neil

IMG_20210402_162606.jpg

Well took mine apart today and found no seal at all fitted. I had supplied them to the rebuilder with the new bracket so not happy. BUT i found half of a thrust washer laying just in side so again do i trust a return or take it to another rep company. Whilst they repaired the gear box they said they could only flush and clean out the overdrive but not test it.

As my engine and box is in the rebuilt chassis and no body on yet it is easy to get to.

Roy

Link to post
Share on other sites

That's nonsense, it is easy to test an overdrive. It needs to be on the gearbox, & you need oil in it, then just attach a motor (cordless drill works fine) to the input shaft, in top gear, spin it up, engage overdrive & watch / listen for a speed change.

I did just that on mine last year before refitting it, & did the same to a friend's Alpine gearbox

Bob

Link to post
Share on other sites

And Pete and Tom Cox test overdrives as Bob has described, but, because they handle a great many, I seem to recall that they use a mains-driven motor rather than a cordless drill.

Ian Cornish

Link to post
Share on other sites
39 minutes ago, ianc said:

And Pete and Tom Cox test overdrives as Bob has described, but, because they handle a great many, I seem to recall that they use a mains-driven motor rather than a cordless drill.

Ian Cornish

Yes they have a purpose built test rig with a robust mains electricity  motor to get the od pressures right up. 

Link to post
Share on other sites
On 4/3/2021 at 4:34 PM, roy53 said:

Well took mine apart today and found no seal at all fitted. I had supplied them to the rebuilder with the new bracket so not happy. BUT i found half of a thrust washer laying just in side so again do i trust a return or take it to another rep company. Whilst they repaired the gear box they said they could only flush and clean out the overdrive but not test it.

As my engine and box is in the rebuilt chassis and no body on yet it is easy to get to.

Roy

Take it to ORS https://www.overdrive-repairs.co.uk/

They are the best at it.

Stuart.

Link to post
Share on other sites

ORS. Solved all my o/d problems after several other ‘specialists’ had been paid. I drove  up to the workshop and stayed two nights in a bnb. Interesting pub in Coventry and a great answer 

Use ORS. Richard & B

Link to post
Share on other sites

Ian did you just send the o/d or the complete box ?

 

My problem is the half thrust washer . is it from the overdrive / rear section or is there one in the box?

it looks like part 83 in the moss book, also one shown between 75 and 76 but not mentioned in the parts list. 76 says thrust washer but points to a gear cog.

As you can tell i don't do gearboxes so all advice welcome.   Specialists are 3 hrs from me.

Roy

Link to post
Share on other sites
5 hours ago, roy53 said:

Ian did you just send the o/d or the complete box ?

 

 

I sent just the OD unit.  I had bought a 2000 saloon box with O/D on the bay for £50 and I sent the O/D to ORS for them to check it out.  As it happened the unit was fine and they charged me £500 to convert it to a TR unit.  I took the box to Pete Cox and he rebuilt it for a very reasonable sum including putting in a TR input shaft instead of the Saloon version.

Rgds Ian

Link to post
Share on other sites

Back to my overdrive issue. Although it worked OK to start with it proved to be intermittent and would drop out on some bumpy roads.

Sometimes when testing statically in the garage the overdrive did stay on. It never stayed on when driving.

Off with the tunnel and after 20 or so years without attention there were a few suspect connections and the solenoid wire insulation was broken at the solenoid. The wire was so brittle it broke off from the solenoid when I tried to disconnect it at the bullet connector.

In with a new solenoid.  The rubber seal interfered with the operation when fitted snugly to the solenoid so I moved it down on the plunger under the bottom face of the solenoid. It still seals against the solenoid so should prevent most **** getting in. Checked the od adjustment which was good.

The bullet connector to the solenoid could be made to break down by shaking it so I replaced it with a more robust connector. The isolator wire connections were coated in gunge so I disconnected and cleaned them. Above the tunnel the relay connections were also suspect so needed cleaning. 

A few minutes testing on axle stands and it tested OK. Tunnel back on and a 20 minute test drive including over some bumpy sections and all seems good.

We have a Register coffee morning tomorrow so I'll take it for a long test run, weather permitting.

Link to post
Share on other sites
18 hours ago, roy53 said:

Ian did you just send the o/d or the complete box ?

 

My problem is the half thrust washer . is it from the overdrive / rear section or is there one in the box?

it looks like part 83 in the moss book, also one shown between 75 and 76 but not mentioned in the parts list. 76 says thrust washer but points to a gear cog.

As you can tell i don't do gearboxes so all advice welcome.   Specialists are 3 hrs from me.

Roy

I would just send the whole thing and have done with it.

Stuart.

Link to post
Share on other sites
9 hours ago, John McCormack said:

Back to my overdrive issue. Although it worked OK to start with it proved to be intermittent and would drop out on some bumpy roads.

Sometimes when testing statically in the garage the overdrive did stay on. It never stayed on when driving.

Off with the tunnel and after 20 or so years without attention there were a few suspect connections and the solenoid wire insulation was broken at the solenoid. The wire was so brittle it broke off from the solenoid when I tried to disconnect it at the bullet connector.

In with a new solenoid.  The rubber seal interfered with the operation when fitted snugly to the solenoid so I moved it down on the plunger under the bottom face of the solenoid. It still seals against the solenoid so should prevent most **** getting in. Checked the od adjustment which was good.

The bullet connector to the solenoid could be made to break down by shaking it so I replaced it with a more robust connector. The isolator wire connections were coated in gunge so I disconnected and cleaned them. Above the tunnel the relay connections were also suspect so needed cleaning. 

A few minutes testing on axle stands and it tested OK. Tunnel back on and a 20 minute test drive including over some bumpy sections and all seems good.

We have a Register coffee morning tomorrow so I'll take it for a long test run, weather permitting.

Sounds like a good result. Hope it passes the coffee morning test. 

Neil

Link to post
Share on other sites
11 hours ago, John McCormack said:

Back to my overdrive issue. Although it worked OK to start with it proved to be intermittent and would drop out on some bumpy roads.

Sometimes when testing statically in the garage the overdrive did stay on. It never stayed on when driving.

Off with the tunnel and after 20 or so years without attention there were a few suspect connections and the solenoid wire insulation was broken at the solenoid. The wire was so brittle it broke off from the solenoid when I tried to disconnect it at the bullet connector.

In with a new solenoid.  The rubber seal interfered with the operation when fitted snugly to the solenoid so I moved it down on the plunger under the bottom face of the solenoid. It still seals against the solenoid so should prevent most **** getting in. Checked the od adjustment which was good.

The bullet connector to the solenoid could be made to break down by shaking it so I replaced it with a more robust connector. The isolator wire connections were coated in gunge so I disconnected and cleaned them. Above the tunnel the relay connections were also suspect so needed cleaning. 

A few minutes testing on axle stands and it tested OK. Tunnel back on and a 20 minute test drive iplunger and biorencluding over some bumpy sections and all seems good.

We have a Register coffee morning tomorrow so I'll take it for a long test run, weather permitting.

Sounds promising John. Thinking more about it I now I recall that what must be well over 30 years ago I had a problem on the 4A with the Type 'A' overdrive not disengaging. It turned out not to be an electrical issue, I found that the solenoid plunger was stuck in its uppermost position and would not fall under its own weight when de-energised. I stripped the solenoid, finely polished the plunger and bore and coated the plunger with powdered graphite as a dry lube before reassembly. I remembered having read somewhere that problems were encountered by the Works 2.5PI saloons on the 1970 World Cup Rally with o/d plungers sticking due to dirt and/or misalignment. As belt and braces I added a very light return spring (too weak to overcome the force of the holding coil) to the solenoid lever to help pull the plunger down when the solenoid is de-energised. I have had no further solenoid issues to date.

Wish I were joining you for the coffee morning - where is it this month, Common Ground perhaps. I look forward to another ride in the long door although to be fair it didn't seem to be going too badly last time!!

Tim

Link to post
Share on other sites
13 hours ago, tim hunt said:

Sounds promising John. Thinking more about it I now I recall that what must be well over 30 years ago I had a problem on the 4A with the Type 'A' overdrive not disengaging. It turned out not to be an electrical issue, I found that the solenoid plunger was stuck in its uppermost position and would not fall under its own weight when de-energised. I stripped the solenoid, finely polished the plunger and bore and coated the plunger with powdered graphite as a dry lube before reassembly. I remembered having read somewhere that problems were encountered by the Works 2.5PI saloons on the 1970 World Cup Rally with o/d plungers sticking due to dirt and/or misalignment. As belt and braces I added a very light return spring (too weak to overcome the force of the holding coil) to the solenoid lever to help pull the plunger down when the solenoid is de-energised. I have had no further solenoid issues to date.

Wish I were joining you for the coffee morning - where is it this month, Common Ground perhaps. I look forward to another ride in the long door although to be fair it didn't seem to be going too badly last time!!

Tim

Thanks Tim,

I suspect I had a similar problem with dirt and oil creating a gunge in the unsealed solenoid. The old solenoid cleaned up is working perfectly on the bench, I replaced the broken wire. I can't think of a logical alternative for it staying on. After the staying on experience the previous weekend it didn't do it again on the road.

The dropping out was probably a coincidence occurring at the same time as the staying engaged. The connections were in poor condition and were the reason for it dropping out on bumpy roads.

I took the car up to our regular coffee at Pie in the Sky at Cowan this morning. The od worked perfectly there and back in all conditions. We even had a torrential downpour to contend with.

I have spoken with a few owners here and none are aware of an od staying engaged as mine did for about 45 minutes over many road conditions. 

 

Link to post
Share on other sites

Hi John,

very envious of your coffee morning at Pie in the Sky. It looks wonderful. But how come there isn’t a gallery photo of a load of TRs outside?

Rgds Ian

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.