The Peerless & Warwick Discussion Forum

mikerf · Status: Offline

Overdrive removal

nigel c · Status: Offline

Hi Mike (numpty!)

Yes they are a fickle thing, only because you cant get to them easily..if they were presented on a plate they would never go wrong. Not heard of anyone taking just the overdrive off in suitue, not sure

Questions:

Is it an A or J type

what oil are you using

has it been "touched" or just washed and fitted

A good person to run your thoughts past is Tom at Pete Cox Sports Cars. He rebuilds all mine (I have a spare spare on the shelf if you want to buy biggrin ) and he might have some ideas you may not have tried.

Tom 01527 522646

mikerf · Status: Offline

Hi Nigel. Yes, you called it. numpty indeed.

It's an A type o/d and filled with the correct (according to all info I've read) oil. Can't remember exactly but it's probably SAE 90.

I did contemplate calling Tom as PCSS reworked my top cover to accept a switch for the reversing light (you may recall this conversation).

I actually took the box (with o/d fitted) to a local trans shop who checked it over for me and declared it in good nick. TBH, the box works fine and there are no issues there. Looking back, I think it's doubtful they checked the o/d. If they did, they should have realised it's not operating.

I really, REALLY don't want to pull the whole engine/box out and can live with the o/d not working for a while but it's still something I'd want to get sorted in the longer term.

I'm a bit surprised that I've not had someone get back to me on the viability of removing the o/d in situ, I would have thought that someone somewhere has tried it. It looks like it should come out easily enough. Take off the prop shaft and it looks as if it would lift out easily but who knows?

Is your spare A type? If so, what would you be looking for? Outright purchase or exchange?

PM or email me your thoughts.

Mike

Car155 · Status: Offline

Mike,

The overdrive unit needs to slide straight back about 8" before it can be lifted or turned so I doubt very much it could be done while in the car. You need to source a pressure tester and check to see if the unit is building any pressure. There is a 7/16 nut on the top right side if the overdrive. Below is the operating lever. This is where the tester is screwed in.

Good luck,

Greg

mikerf · Status: Offline

Hi Greg.

I saw this pressure tester on a youtube video (someones rusty beauties? Something Eastern European?). But despite searching, I can't find one in the UK. The only available item I've seen for sale is in the USA. I have, however, slackened the bolt you speak of and there is pressure as the oil pushes out past the bolt if it's not fully tightened.

nigel c · Status: Offline

Mike, a little alarmed to your hazy memory to what oil you may have in it. I have always used SAE 30 in mine and it works very well. SAE 90 IMHO opinion would be way to thick?

Frank · Status: Offline

I've just removed the sae90 and replaced it with sae30, on Nigels reccomendation.

With the thicker oil, the O/D went in like a rocket, but wouldn't come out again. I have a J type.

On an A type, there's a gauze filter above the big casellated nut on the bottom. Item no 12 on the Moss diagram.

I think the pump falls out when you remove it......

F

mikerf · Status: Offline

Hi Nigel. Age doesn't come alone, you know.

In fact, I did actually speak to Tom at PCSS yesterday and mentioned SAE90 and he was ok with that although I should have said HYPOID 90 which I pretty sure is what I have in. Quote from the Duckhams website "For all A Type o/d gearboxes, 40 grade gearbox oil is best but if you can't get any then Hypoid 80/90 will work. The overdrive likes this but the gearbox might have a heavier change due to the higher viscosity. "

Anyways, he suggested a number of tests which I'll try and, specifically, getting a pressure gauge to check the oil pressure in the box. He also suggested a couple of contacts one of whom I called right after speaking to Tom. He's given me other tips including how to check the operation of the pump without removal of the o/d AND how to use a right angle (blunt) pick or similar to check if the steel ball on the pump plunger is free. Apparently, this can be another problem area.

As this would necessitate draining the oil, I may take the opportunity to change to a lighter grade.

Not sure when I'll get around to all of this so may be motoring on just the 4 speeds for the foreseeable but I'll keep th site posted.

One thing Tom did say was that you'd need a minimum of 9 inches clearance to remove the o/d (preferably 10) so it looks like it would have to be an engine and box out job if I eventually need to replace the o/d.

Car155 · Status: Offline

Mike,

Here is a link to a web site of a UK company I buy parts from to rebiuld ODs. They have the gauge set up for 60 lbs. In reguards to the oil to use, if it is a gear oil it should be the GL4 designation. GL5 and above has an additive that is corrosive to yellow metal. That would include the Syncros and several bushings in both the trans and the OD. I use a synthetic oil from Redline, MT-90. There are other brands that make the GL4 in synthetic as well. Most of the racers in the States are using the Redline variant.

The best web site I have found to read and understand the A and J overdrive units is the Buckeye Triumph website. Link provided. They give you the information you need to test your unit.

www.buckeyetriumphs.org/

www.overdrive-repairs.co.uk/product-category/a-type-spare-parts/page/2/

Hope this helps,

Greg

mikerf · Status: Offline

Hi Greg and thanks for the links.

I actually spoke to a guy from o/d repairs yesterday and he offered me a money saving tip. I don't need a gauge to check the pressure. With the rear of the car on stands and in 1st gear, remove the plug that the gauge would go into and check to see if the oil pushes out (which it should do) , if you put your thumb over the hole and oil still pushes out, there's enough pressure. If not, pumps not working. But there are other fixes he's suggested before pulling the box.

Re oil type for the box & o/d, I've had as many opinions as people I've spoken to ranging from Nigel's SAE30 right up to SAE80 with everything in between. An that's from guys who specialise in either od/ repairs or parts.

Frank, I'd be really worried if the pump fell out from the sump because, by all accounts, it shouldn't.

The other tip I got from Overdrive Services (whom Tom at PCSS directed me to) was to remove that sump plug and strainer, drain oil. With the car on a ramp and working from underneath, elevate the rear wheels and have someone rotate them. Shine a light up into the sump plug hole and check for up and down motion in the pump. If it moves, it's working. Next test is to get the pump in it's topmost position and, using something narrow and right angled, check that he ball that sits at the end of the pump plunger is free. Apparently, these can stick if left unused for a long time (as mine has been).

So, lots to try before I resort to robbing the piggy bank for a recon.

One final suggestion I was given, and this sounds a bit brutal to me, was to drive the car and drop the clutch pedal as if you were trying to free off a sticking clutch plate. Might free off the cones??? Not sure about that one.

nigel c · Status: Offline

great that you're happy to take on the role of Gearbox Guru for us all Mike biggrin

mikerf · Status: Offline

Wait until I've had a chance to try all this out Nigel.

This has the potential to go horribly wrong.

Btw, Greg's recommendation of Buckeye Triumphs (which I'd never heard of or visited before now) is a really good one. Lots of technical stuff.