Gearbox Rebuild

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rbgosling
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Gearbox Rebuild

Post by rbgosling »

Since my last post on the subject was already at 3 pages of questions, suggestions and ideas before I even started, I thought it better to start a new thread documenting the actual process.

First, some brief background - For the last couple of months my car has been jumping out of 1st gear more often than not when pulling away from a standstill - so much so that I've pretty much given up on 1st and now start off in 2nd. The enforced 3-week break resulting from the COVID-19 pandemic provided an ideal opportunity to carry out the work while I wasn't depending on the car.

First off - there are instructions on how to do this in the Workshop Manual. Don't bother. They describe each step in minimal detail, and assume the use of several special tools. I have used this pair of videos on YouTube, which walk through the whole procedure step-by-step, and basically I've watched each step, copied what was done, and moved on.

How To Rebuild a Toyota W58 5 Speed Transmission - Part 1
How to Rebuild a Toyota W58 5 Speed Transmission - Part 2

These also include various tips and suggestions, and don't assume you have any special tools. It does assume you have access to a hydraulic press, and at the time of writing I've got to a point I can get no further without this. You'll also need a gear puller, which I did already have.

I could only find one supplier in the UK selling rebuild kits for the W58, and they wanted about £500 for it. There are a number of sellers in the US selling them for around $100, even with the shipping and import tax I got mine for about £150, delivered in a couple of weeks. The link to the kit is W55 W56 W58 Toyota Transmission Rebuild Kit 5 Speed 1978-91 (BK162WS). If the link doesn't work, the seller is usa.industries, but if you just do a search on W58 rebuild you'll see several options.

This is what the kit looks like:

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

First job - remove the entire engine and gearbox assembly. Having done this 3 years ago for my engine rebuild I should know how to do this... and pretty much got it all right.

Things to remember to disconnect include:
  • The gearstick. This is the one I forgot last time, and couldn't work out why the engine wouldn't move very far!
  • Reversing light switch on the gearbox.
  • Speedo drive.
  • Two wires connected to the back end of the cylinder head, that it's hard to see until the engine starts moving.
  • Engine earth strap.
  • Power steering. Due to the inaccessibility of the pump with the engine in place, I chose to disconnect the hose ends connected to the fluid reservoir and the rack.
  • Exhaust. I managed to separate it between manifold and downpipe, but this can be a PITA, and it is possible to remove the engine with the downpipe still attached.
You'll need to remove the coolant, power steering, and windscreen washer reservoirs from the nearside wing, they get in the way.

I've used two different hoists and found that neither could get close to removing the engine over the front. However it does come over the near side easily enough, with the hoist on maximum reach and the road wheel removed so it doesn't get in the way of the hoist's access. Definitely takes two people, one to operate the hoist and the other to manoeuvre the tail of the gearbox carefully out of the engine bay. Of course, if you have a ceiling-mounted hoist it's a different matter!

N.B. drain both engine and gearbox oil before removal. I didn't drain the gearbox oil (couldn't find a socket to fit the drain plug - think it's 25mm, got one on order - so I left the oil in). Turns out the gearbox seals against the propshaft as it enters the gearbox; with the propshaft slid out, there's a massive hole out of which all the gearbox oil will drain all over your driveway. Or, worse, the common driveway you share with your neighbours... (luckily the guy opposite has a Midget, a Massey Ferguson 35, and a grey Fergie he's in the middle of restoring, so he's sympathetic!)

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

Next step - separate the gearbox from the engine. Not much to this, undo the nuts, break them apart slightly with a pry bar, then slip them apart.

Removing the bell housing is straightforward too. If you can get the bolts loose. They will be tight!!

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

Now we get into the meat - this was yesterday. First job was to pull off some ancillary bits - reversing light switch, speedo drive, bias springs, gearlever housing. All fine except the speedo drive didn't want to budge. Turns out this is not a problem, the rear cover comes off fine with it still in place.

Then remove the 9 bolts that go from the rear cover, through the centre plate, to the front cover. Well, 8 came out fine, the 9th the head sheared off, once enough grunt was applied to it. Oops. Might call that a dowel from now on.

Then the rear cover came off. Enough for one morning (in the afternoon I play stay-at-home dad, for now, while my wife gets on with her many tasks)

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

More disassembly on Tuesday. Got the front cover off, and removed the rails and forks. Got the 5th gear assembly off the countershaft no problem with my basic 2-arm puller.

The next step, according to the video, is to move the reverse gear off its splines on the main shaft, which will give access to the screws holding in the retainer plate for the main shaft. He did this by whacking the end of the main shaft - see from 26:20 in the video. Well, this didn't work for me, the reverse gear stayed stubbornly put with no sign of movement at all after several enthusiastic whacks with a lump hammer.

Fortunately I have made a friend via a local classic car Facebook group, he lent me the engine hoist and also has a hydraulic press he is willing to lend. I'll need it anyway to get the 5th gear off the main shaft, so hopefully I can find a way to use it to shift the reverse gear too. That's the next plan, for Wednesday.

In the third photo, see the amount of rust on the bolt that broke while splitting the gearbox, still sticking out of the front housing (at the back of the workbench). Odd this, as the other 8 were clean as a whistle. But if this is what stopped the bolt turning then there may still be a chance of getting it out - I'll give it a try.

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

Wednesday - limited progress. I used much of my allotted time going to pick up the hydraulic press that I have been very kindly lent (plus shopping and other chores while I was out and about). Only actual progress was to press the reverse gear on the main shaft off its splines - the task that the video suggested could be done by hammering on the end of the shaft, but the press I feel does a much better job.

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

Thursday - got the rest of the gearbox disassembled. The hydraulic press is a godsend - used not only for the 5th gear as advised by the video but several others. I feel much happier using this than whacking stuff with a hammer, and the job certainly wouldn't be possible without it. Now I've tried one I'm tempted to get one of my own anyway, even without needing it for this job - I've seen them for around £60 on eBay.

That didn't take too long, so I thought I'd get the worst of the crud off the outside of the casings. Wasn't bothered about getting them too clean - they can't be seen, this car is for driving not showing, and they'd get filthy soon enough. Yet.... once I'd got started, and seen how easy the crud comes off, it was not really possible not to keep going! Far from immaculate, but looking much better than they did - and most importantly, reduces the risk of getting filth on my hands and introducing it into the 'box during re-assembly. I'll clean the rest tomorrow.

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

Pete Boole
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Re: Gearbox Rebuild

Post by Pete Boole »

You're right Richard - a hydraulic press is one of the most useful tools for the workshop. Good to see the right tools being used for the job! You're making great progress :D. Have you identified any obviously worn parts yet?

Pete

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Re: Gearbox Rebuild

Post by rbgosling »

Pete - nothing visibly damaged that I can tell. Gears look like new. I guess the syncro rings could be a bit worn around the edges, enough to cause problems but not obviously visible.

Friday's progress: First a bit more part cleaning. Work through all the piles of bits, identifying what's in the rebuild kit and putting the new parts in place of the old parts within their assembly. Then a start on re-assembling the main shaft.

Bit of a cock-up initially, as the 1st gear syncro ring got out of position with the syncro sleeve while I was trying to press on the bearing, which I only noticed when the bearing wouldn't press on as far as I thought it ought too (and neither the 1st nor second gears would spin on the shaft!). Managed to get the bits off again, re-align, and put back on, all looks good now.

I don't plan to do anything over the Easter weekend, so back on to it on Monday!

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

Easter Monday - no progress, Heather was feeling pretty crap (no, not the C-word!) so I got to be Daddy / Teacher all day.

Tuesday - better progress. Finished re-assembling all the shafts, and got them installed into the centre plate. Made a start on installing the rails and forks, but came to a halt with the 5th/reverse fork - I'd rather mangled the roll-pin when removing it, and I'm still waiting on delivery of a replacement. Should be here tomorrow at the latest, promises eBay, but we'll see, these are not normal times. I probably could have got on with other bits while I'm waiting, but I'd rather stick to doing everything in the exact order in the video, for fear of missing/forgetting something if I start going out of sequence.

I went rather hotter with heating parts to help them slip on more easily - 150deg C with the main shaft reversing gear, and 200deg C for the main shaft 5th gear and the counter shaft gear and 5th gear syncro assembly. Even at those temperatures the gears on the main shaft didn't slip on straight away, and I preferred to use the press than to tap them on like the video. The reverse gear on the counter shaft slid right on, and the 5th gear syncro went on with only very slight tapping.

I'd hoped to get all the heating done while Heather was out for a walk with the boys, but she came back before I was done. I think the smell of burning oil in the kitchen would have given me away anyway!!

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

Friday (yesterday) - got fed up of waiting for the roll pin that is now two days past the last delivery date, and decided to press ahead with whatever else I could do. Note the old screwdriver stuck through the roll pin hole - both to hold the fork in position, and to ensure I don't thoughtlessly close the 'box up with the roll pin not yet installed!

Turns out "whatever else I could do" wasn't much. Got the other two rails and forks installed. Next job was to install the front cover - but this is where I should have watched the video more diligently before I started. An anaerobic gasket sealant is recommended, and I don't have any in stock. Cue another eBay order, and a wait until next Wednesday at least for it to turn up.

At least today (Saturday) the roll pins have arrived!

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

Stuck with a week of unwanted no-progress - I needed some gasket sealant and eBay delivery times are not currently what they usually are. Finally arrived a couple of days ago, but I was enjoying myself with the children too much over the weekend to find any time for the 'box.

Anyway, this morning I got the front and rear casings back on, and the front cover in place (amongst other chores). Good thing I noticed the speedo drive gear lying around my workbench, I don't think the video reminds you to put that back on!

Next tasks - gearlever housing, then I can re-attach the 'box to the engine. It'll be another day or two before I can get it back in the car though - I found two head-to-exhaust-manifold studs missing, I ordered some new ones which arrived this morning but they are too long so I'll have to wait until shorter ones arrive before I drop the engine back in the car.

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"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

Pete Boole
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Re: Gearbox Rebuild

Post by Pete Boole »

Good work Richard. Did you get the broken stud/bolt out of the casing? Looking forward to your report on the finished article.

Pete

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rbgosling
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Re: Gearbox Rebuild

Post by rbgosling »

Yeah - the broken stud came out with surprising ease, turns out it was the rear cover it had corroded to rather than the thread. Ran a drill through where it had corroded to clean the hole, and sourced a replacement bolt.
"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2004 Jaguar X-Type Estate

Esprit2
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Re: Gearbox Rebuild

Post by Esprit2 »

Richard,
In message #5, there are 3 images that failed to upload. At least I can't view them, but all other images show up. Is there something in those photos that is worth an effort to try posting them again.

Regards,
Tim Engel

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