Cheers John for the write up looks like the place I took her to didn't exactly fix her no wonder she wouldnt go in gear.
Can I name names as to the garage that wanted to charge me £300 for the repair/ rebuild? Not sure whats happened with the selector forks they should be the good ones off the freelander box, the stripped bolts were not there when I took it in for sure as I changed the top casing for a spare, after a dodgy inspection hole/ drain hole as I done it up to tight with the ratchet gun and it umllered the hole. Basically took the box and a load of spares to a garage in Bristol that specialises in boxes and left with what I gave John to fix after fitting with no joy and 2-4hrs of garage labour to pay.
Looking forward to getting her on now after I get the threads heli-coiled.
Longer freelander final drive
Torsen Type B LSD
Updated bearings
Once again John thanks much appreciated
Wayner

 

Another top quality thread :unionflag:

 

Most definitely. I really enjoy your threads John - keep it up!

The inner workings of a gearbox are something I've rarely seen and find them to be a work of art.

 

Nice write up John-they actually look quite simple boxes to work with.

 

interesting thread, i've got a ford gearbox laying around id like to dismantle for my own education.. any special tools needed?

 

Good idea. That's exactly how I learnt. Self taught. Back around 1972, I bought a scrap gearbox from a local breaker yard. Cost me 50pence. Sounds cheap, but, that's about 1/4 the cost to fill the tank in my Mini 1000 back then. Money well spent. Prior to that, I worked on much smaller gearboxes ~ Motor cycles. That was an enforced education following too many clutchless gear changes... That's another thing I no longer do... most uncool... and costly ....

 

Did you find out what was wrong with the original selector forks?

 

No, they look OK just 'felt' loose. The little hair spring arrangement I've not seen before on any PG1 Box I've worked on.
..

 

1st Class

Great quality pics and top notch info.

Wife dont mind you ripping off her towels....

Get on and do it, sort it and learn....way to go.

Nice job. Clean work.

Topdog

 

Great quality pics and top notch info.

Wife dont mind you ripping off her towels....

Get on and do it, sort it and learn....way to go.

Nice job. Clean work.

Topdog

Thanks for the compliments KevinM/Top dog and other folks.

Thanks to an evolving ever more lazy and uncaring Nation, the MGs and Rovers are an endangered species... extinction only a matter of time. The Nation's loss.. We've become good at losing things...:angry:

Our 'worthless' cars are more highly regarded elsewhere in the world. Only this week, I've sent a few small old Rover used parts to faraway places such as Argentina, Denmark, Germany and Spain. Those folks are delighted to be able to keep their cars going with little parts they are unable to find in their countries. It gives me pleasure to help them when I can.

I do these illustrated threads in the hope that in some way I can help keep a lot more of these fine old cars going a few years longer ~ because I know they're worth it.

By the way, those are my towels .. I have a few of my own now...

Now retired, with my wife still working, I often do the weekly shopping. I have the time for that now. If I see some good quality end of line Towels on offer in the supermarket I get them. Sometimes my bargains are so nice my wife commandeers them for the house ... rascal!

More time means I can prepare meals for the family, roast dinners, curries the lot. Very satisfying to see their plates clean particularly my wife and younger son who are a bit fussy where food is concerned. Cooking and fettling old cars appeals to my creative 'bent'...Oh Matron ....... For much of my working life there was an end product but, mostly unseen and far less creative and tangible unlike cooking and keeping old cars going. Wouldn't want to do either full time though.
.

 

Getting the threads heli-coiled this week so should be going in the zr next week looking forward to the difference in ratios and LSD, should be one nippy little zr with a wee bit of tuning, selector forks were out of the freelander box, funny though I know the garage changed the fifth gear/ reverse synchro mech so maybe the problem was the selectors not the mech.
All good now just needs chucking on the zr.
Spec of the box is>
Pg1 diesel box.
Freelander longer final drive.
Torsen type b diff.
Steel caged bearings.

Going into my lightweight ZR express diesel running
Sdi's.
Stage 2 Hybrid turbo.
Full custom exhaust.
Open cone.
Decat.
Water meth injection kit.
Ported manifolds.
Box and car should be good for where legal 132mph, it's my daily runner so can't go to crazy but she'll be going and tracks and drag strips to show what a half decent old MG ROVER can do.
Cheer up too John as a nation I think we still have a lot to proud of engineer wise, Formula 1 factories and people like BAE, Rolls Royce, McLaren and lotus etc...
Take a look at forge auto sports for a little company doing things in the UK not far from you read a good article about them the other day.

Love the cooking also too, as I work nights I quite often end up if its raining not under my collection of cars and in the kitchen listening to some tunes and creating some tidy dinners for he family.

 

.
Cheer up too John as a nation I think we still have a lot to proud of engineer wise, Formula 1 factories and people like BAE, Rolls Royce, McLaren and lotus etc...
Take a look at forge auto sports for a little company doing things in the UK not far from you read a good article about them the other day.
.

...

Yes we do indeed. Of course and I've found the Folks at Forge very helpful.

Nobody is more keen to see our F1 teams finish in front of the rest, especially those red jobbies with the image of a Donkey dancing in custard on them... :lol:

All of those and many others you don't mention have much to admire about them.

It's just that we've dropped the ball in so many other ways that frustrates me occasionally

Back on track. Let us know how your "Express" shapes up with the modded TorSen PG1 fitted.
.

 

What would a diesel gearbox be like in a 1.8 k series ZR ? Anyone know ?

 

In a petrol manic with the diesel ratios and final drive. You'd have a very long legged driver with that set up ... The very high 5th gear... Ideal for long motorway cruising work where economy is the main thing but you'd have to use the lower gears a lot when speed drops or the engine will struggle.

On average, petrol engines rev 30-40% higher than an equivalent diesel and so the gear ratios are tailored to suit those differing characteristics.

 

Do you know the speed in fifth gear per 1000 rpm between the diesel and petrol gearboxes ?

 

Depends on size of wheel used. Measure the rolling circumference and by using the ratios and final drive, you can work out the differences in speeds.

Over on Rovertech.net there's a sticky showing all the various ratios and final drives on Rover/MG gearboxes. Not seen it for years but, it should still be there.

Someone may have already worked out that for you ~ try a search. I've seen those speed/1000 rpm figures somewhere. If the diesel has the same size wheels as the petrol, you can glean the information that way.

 

Every article I have read on gearboxes says "don't attempt to repair yourself", "Special Tool BG1324 required", "send it to a specialist" etc. Yet you can do this in your back yard with a socket set and a small hammer! If I had a hat on I would be taking it off to you MGJohn.

 

Pssst .... wanna buy a hat? Got nice one going cheap.

... Thanks ...

P.S. That 50 pence I spent on buying an old gearbox all those years ago was money well invested.

 

There's more.. some things come in threes so they say.

There's more.. some things come in threes so they say.... :yikes:

=====================================================

Having reassembled this Diesel Spec + TorSen for another Rover enthusiast a couple of weeks ago, I thought that would be the last PG1 I would be working on for a while. Then my son who uses his high mileage 620ti for work tells me his car has lost 5th gear. He has two spare ( worn ) 620ti PG1s with "bearing troubles" apparently so I split the casings on one and discovered the various bearings I could see without removing the Differential were all good condition steel caged items. Good premium quality too. They looked and "felt" fine. More checks to follow. I'll check the hidden differential bearing tomorrow to see how that shapes up. So far so good for that box. I'll get that checked and when he removes the faulty one on his car, this will be ready to go straight on.

I then turned my attention to the other PG1 which was the original one that came with the car when he got it about seven years ago. The nearside Differential bearing was cageless and as soon as I split the casings, the full extent of the damage cause by the worn and broken up bearing became apparent. A number of teeth on the Crown Wheel were broken off.

The bearing on the top of the countershaft was interesting because it was steel caged. It's the one with the groove in the outer race to accomadate the C-Snap ring. As far as I know, this gearbox has never been worked on since it left the factory. Thus, the steel caged bearing could be the original factory fitment. Here's a close up showing the details :~

An NTN OPG2 ... ?? I wonder if these can still be obtained.

By the way, the broken off pieces of the Crown Wheel's teeth were lodged in the top of the gearbox having been thrust there as the Crown Wheel rotated :~

This is what I removed :~

This is the broken up Nearside Differential Bearing which allowed the Differential to oscillate out of true and break off those Crown wheel teeth :~

Moral: At the first noisy signs of Differential Bearing wear, stop using the car and get it repaired before much more serious damage occurs.

By the way MGJohn, when working single handed, how do you hold the prongs on the C-Snap ring apart to allow the casings to be split. Like this ... ... :~

Where there's a will, there's a way...

 

Nice tip for holding the c clip open needed three hands when doing mine.
Getting heli-coiled this week and should be in next will report back, only one of the holes needed doing the other just needed re taping bit of a bonus.
Now must get back to fixing the water meth kit.
Nice to see you've got another PG1 to play with. My mechanic said it was a nice job you did too, they thought i'd taken the box to another garage I said no took it to a Rover specialist

 

I completed the check of my son's better 620ti Gearbox and all the usual suspects bearings looked and felt like new except the big one on the outer end of the input/mainshaft. That one looked like new but, looks can be deceptive. Using petrol, I washed that bearing which then looked in even finer condition....

This is the one I refer to although this is on a different gear cluster :~

Then was able to see how much play was present. Quite a bit when compared to the new one which had no detectable play at all as to be expected. I will fit a new steel caged replacement and reassemble the box tomorrow and my son can do the swap at his leisure.

His other badly worn gearbox will need a good replacement Crown Wheel as well as all the replacement new bearings. My son may simply put the good type B TorSen into his Rover Metro VVC.

 

Bit late to the party, but its great reading stuff like this, you read all the warnings as its been said, then you read something like this and you see why we are in danger of losing what makes/made this country Great, innovation and resourcefulness!!

Was the same through all the years I was running 924/44's, all you ever heard was "ooo that'll be expensive if it breaks", well yes it will if you take it to a garage that changes £60+ an hour labour.
Doing it yourself is so much more satisfying that handing over a months pay!

In my early days I broke a few cars, but you certainly learn quicker that way lol

That's a great write up John, keep it coming

 

Thanks for a great and informative thread regarding the gearbox disassembly and fault finding.

MGJOHN,what could be the cause of a very noisy reverse on a PG1 GEARBOX?
It selects reverse without any problems but as soon as you start moving backwards it becomes noisy and if youre reversing on an incline it gets even worse?

all help and suggestions gladly appreciated.
ps its coupled to an Lseries diesel engine[freelander1 2wd]

 

Very hard to say remotely without experiencing the car and the noise itself.

Could be any number of things. Might not be gearbox related.

What sort of mileage and what level of maintenance has the car had since new? Has anyone drained the gearbox of its lubricant to see if it has sufficient quantity or any at all. I have known a few PG1s to give BIG problems because their lubricant has all drained away over thousands of miles via worn seals.

 

Ive only had the car a few weeks now
,but its definately gearbox related.I jacked the front wheels of the ground and tested it that way listening where the noise is coming from ,at 1st suspected it was coming out the IRD unit,luckily not.

Will drain and check gearbox oil level over the weekend.

 

Ive only had the car a few weeks now
,but its definately gearbox related.I jacked the front wheels of the ground and tested it that way listening where the noise is coming from ,at 1st suspected it was coming out the IRD unit,luckily not.

Will drain and check gearbox oil level over the weekend.

did this the weekend past ,oil level was on correct level and type so I suspect the idler gear has been damaged

 

Looking more closely at the selector fork assemblies on this gearbox, they felt a little loose when handling them and something else was different too. There was a small hairspring on the assembly which I'd never seen before. Here it is in this close up picture; right in the middle :~

That small hairspring "mystery" to me at least partly solved.

Browsing various Rover Gearbox threads, came across a Rover manual extract about this little assembly. It reads :~

De-Encrypted it should read :~

104. Interlock assembly ~ Later Gearboxes.

105. Gear selector - 5th/Reverse Gears/with reverse brake.*

106. Spring - reverse brake.*

107. Lock Plate - reverse brake.*

108. Taptile Screws - reverse brake.*

* Gearboxes with reverse brake fitted.

Reverse Brake !!! ??? Not come across this term before ~ guessing here, does it slow the reverse idler or what?

Anyone enlighten me on this "reverse brake" fitted to some later PG1 gearboxes apparently ?

 

taken of another site


the PG1 has a reverse brake using the 3/4 syncro hub, and a little 45* ramp to stop/slow the gears spinning before engagement.


in the freelander 97-01 workshop manual there is a detailed description of the operastion of the reverse brake

 

Ahah ~ thanks for that. Clever ... if it works.

I suspected something on those lines as I've noticed that if you wait in neutral a short while to allow the gearbox internals to settle before selecting REVERSE, there's less chance of that crunch sound then. What also helps is having a clutch in good condition. Any signs of clutch drag, maybe as a result of a worn slave cylinder seal not fully releasing the clutch or poor cable, causes that crunch noise when selecting reverse on the PG1. Even very slight clutch drag will keep the gearbox internals moving in neutral.

After renewing and bleeding the little seal in the hydraulic slave cylinder of the Rover 620ti in the family, it is possible to select reverse .... silently.

 

just a pity that on the Freelander1 the master and slave cylinder is a sealed system and theres no bleeding nipples ,you have to replace the whole system if theres problems

 

im planning on changing the clutch and pressure plate in the next month or 2 ,so while the gearbox is out ill take the casing of to get a closer look at the insides.
on another note ive already enquired at our local LAND-ROVER agents what will the cost of an idler gear and worst case mainshaft be.their reply is a 6-12 week wait as theyll have to import it !!!!

 

SO i started yesterday[friday]afternoon to disassemble the gearbox/IRD/SUBFRAME

 

AFTER A LOT OF STRUGGLING and fighting with overtightened bolts i finally got the gearbox out and stripped it to see whats the noise.
As i suspected the reverse idler gear has damaged teeth

http://img823.imageshack.us/img823/2732/21042012001.jpg

http://img823.imageshack.us/img823/2732/21042012001.jpg

http://img823.imageshack.us/img823/2732/21042012001.jpg

http://img696.imageshack.us/img696/1391/21042012002.jpg
http://img826.imageshack.us/img826/4486/21042012.jpg

 

cant figure this photo uploading out,can someone please tell me where im going wrong


strangely enough my gearbox has the reverse brake on the 4th gear aswell as taper bearings on the diff.

 

cant figure this photo uploading out,can someone please tell me where im going wrong


strangely enough my gearbox has the reverse brake on the 4th gear aswell as taper bearings on the diff.

try this

 

thanks for that ,where im struggling is at the go advace option .what do i need to select to make the pics appear?

 

Hmmm ..... someone has been impatient or heavy handed.

If that Reverse Gear Idler is the same item as fitted to Rover 620ti PG1 Gearboxes, I have a spare one in good condition.

 

I think the problem might have come from the previous owners, driveway was very steep downhill and no way of turning around att the bottom so there was no choice but to reverse it out.this happened for about 9years daily