Blimey. All I did was blink and seven months passed by. Well to be accurate I got distracted renovating a bathroom and, because of my well-documented inability to focus on more than one task at any given time, work on the Triumph pretty much slowed to a stop. However, the stars are gradually aligning – spring finally seems to have arrived and Mrs Rusty is overjoyed that we once again have a functioning toilet so I’m sensing an opportunity to sneak out of the house whilst she’s not looking and have another poke around in the oily depths.
Before I go any further I should probably add a small update on my previous post – despite my best (some may say heroic) efforts, the Triumph didn’t make it to the All British Day. Once I had finished faffing around with the cooling system I made a last-minute executive decision to try to sort out the clutch which bites about 5mm from the bottom of the pedal travel and makes the car a bit difficult to drive. The day before the event, and in the hope it was a hydraulic problem, I swapped over the known good master cylinder salvaged from the TC, fitted a brand new 7/8″ bore slave cylinder procured from Chris Witor and bled the system thoroughly but this had no effect on pedal travel. I presume that the problem is inside the bell housing – most likely the tapered pin securing the clutch release fork to the cross shaft has sheared and needs to be replaced. It’s a gearbox out job then. Luckily/annoyingly I’ve been there before…
I feel I’m about to experience a case of Déjà vu…
As I hadn’t driven the car a long distance before, and I had no idea whether the problem would get worse as everything warmed up and leave me stranded with no clutch, I decided to take the modern to the All British Day instead (yep, I’m a coward like that). On the plus side this meant I could go with family in tow, making me much less of a Larry-no-mates than I would have been solo. The ABD was great fun, so many cars (including a great display of Triumphs) to see – and I could tell by the look of general ambivalence on her face that the wife loved it too.
Yellow Stag anyone?
So, whilst I haven’t had a chance to do much actual work on the car, it has needed to be shuffled around my vast estate a few times to make way for plumbers digging up my driveway and this has drawn my attention to the less-than-healthy condition of the engine. It knocks a bit when starting from cold (they all do that sir) and it enjoys spraying my driveway with a fine mist of oil from the exhaust pipe each time it runs. I’ve had my suspicions about the existing lump since I bought the car – the oil was black and filthy, the filter canister contained no paper element and the valve gear was caked in an appetising layer of black sludge (I did buy it from a breakers don’t forget). Out of morbid curiosity I’ll run a compression test and, if I’m feeling really fancy, might hook up my oil pressure gauge just to see what’s going on but seeing as it’s not the original block supplied with the car from new (the engine number is from a PI) I have no particular concerns about swapping it over for something a bit less crap.
I have my suspicions about this particular lump of iron and sludge…
As luck would have it, my garage floor is still adorned with the 2500 lump I removed from the TC prior to it ‘moving on’. Whilst I don’t know much about the history of this engine it has a nicer aura than the one that’s currently in the car. When it came into my ownership the oil was clean, the filter element was new and the valve gear was sludge-free. The block and head also seem to be sporting various new gaskets, new freeze plugs and a fresh(ish) coat of paint which makes me wonder if it has been rebuilt at some point in the past. Annoyingly I didn’t run a compression or oil pressure test on it whilst it was up and running in the TC but it didn’t knock from startup or spray oil from the exhaust and has no discernible fore-aft play in the crankshaft so my money’s on it being a safer bet in the long run.
The TC giving up its innards.
So, seeing as the gearbox is going to have to come out to fix the clutch I thought I might as well go the whole-hog and swap the engines over at the same time. I also have that newly-rebuilt OD box sitting all seductively in the corner of my garage which might as well be put to good use and swapped in too.
So, that’s the to-do list sorted for the coming weeks then, but what about more immediate progress? Well, to give myself an ‘ooh, something is happening’ ego boost I decided to start small and swap out the front wheel bearings. Having been off the road for 10 years or so, the bearings needed to at least be stripped, cleaned and re-greased so I thought I might as well go the extra mile and fit new ones. The replacement Timken bearings were sourced from Chris Witor a couple of parts orders ago and have been sitting on the shelf in my garage ever since.
Ready and waiting to go.
The replacement process begins, as with all good stories, with the jacking up of the front of the car and securing it on axle stands. The brake caliper needs to come off first – it’s technically held on with two bolts but removal and refitting is much easier if the bolts holding the strut to the vertical link are loosened slightly too. Once they’ve been slackened, the caliper can be unbolted and suspended from the front coil spring by a length of wire to avoid any tension being put on the brake flexi hose.
Just hanging around.
To remove the hub itself the dust cap needs to be levered gently off of the centre of the hub, exposing the castellated hub nut. The split pin securing the nut to the stub axle can be pulled out with pliers, after which the nut can be removed leaving the hub free to be pulled straight off. This process may or may not leave the inner bearing roller and/or grease seal attached to the stub axle – if so they can be pulled or gently tapped free. If the bearing rollers have remained in the hub, they can be pulled out leaving just the races, which are a press-fit in their seats. Each race can be tapped out from the opposite side of the hub through the two small notches that BL kindly machined – I have a handy box of long carriage bolts stashed away for such purposes.
Removing the old bearing races.
You’ll probably find it cleaner and easier to see what you’re doing if you remove as much rancid old grease as possible from the hub assembly first – especially if a previous owner or their friendly mechanic has stuffed the cavity full of the stuff as is often the case (and by all accounts completely unnecessary). A few bold taps of the hammer, alternating between each side of the race should see it pop right out. Be bolder if not. Repeat for the other race et voilà – the disassembly process is complete. Enjoy a pat on the back and have a beer.
Here’s what you hopefully be looking at…
Despite having new bearings to fit, out of curiosity I cleaned off the old bearings and their races to see what condition they were in. Whilst not showing heavy wear or damage, the races showed some signs of light scoring and heat-related discolouration so their replacement was definitely due. The grease also smelled a bit burnt and around the bearings it had a very low viscosity, resembling more of a heavy oil than a grease. Whether this was age or heat-related deterioration, or the wrong type of grease had been used at some point in the car’s maintenance history I don’t know, but it felt good to be cleaning it all out.
Probably about time for replacement.
The first step of reassembly is to drive each of the races into its seat in the hub. There are several ways of doing this – you could use a hydraulic press (easiest, but I don’t have one), you could drive it in with a suitably sized socket, or you can drive it in with a punch of some description. Whichever method you choose, the aim is to ensure the race is fully seated in the hub without inflicting even the slightest damage to the surface on which the rollers will run. Being the daredevil maverick I am, I chose Option 3 and used the same non-hardened carriage bolt that I used to remove the races to drive them home – tapping the races progressively into the hub, working around the top lip in a 12, 6, 3, 9 o’clock pattern. This has to be done extremely carefully as it would be very easy to slip and scratch the bearing surface rendering it scrap. Taking it slow and steady I got away with it – the obvious change in note of the hammer tapping the race being the signal that they had bottomed out in their seats without a single slip, scratch or bludgeoned finger. Another celebratory beer? Thank you, but not whilst I’m working with tools…
The next step in the assembly process is to pack the new bearing rollers with a dedicated wheel bearing grease – I used a Timken grease as presumably they are best placed to know the lubrication requirements of their own products. Again, there are a couple of options here – you can buy a fancy bearing packer contraption or you can do it the fun, messy way. I chose the latter of course – this involves placing a nice big blob of grease in the middle of one palm and with the other hand biting away at the blob with the outer edge of the bearing roller until fresh grease is pushed through and out of the other side (see picture below). This is repeated progressively around the circumference of the bearing until it is fully greased. I then also run the grease around the rollers with my fingers to ensure they are covered. The races installed in the hub also get a coating to avoid dry spots.
Next the grease seal needs to be fitted to the stub axle – I went for the decent ones with leather inserts available from Chris Witor. These can be a bit tight and therefore tricky to fit, but a very light smear of grease and some gentle persuasion with a small hammer around their perimeter saw them sitting where they should be.
At this stage the inner bearing roller can be slid over the stub axle – it might need a careful tap if there is a small lip for it to slide over (although if there is significant wear to the stub axle it might be time to consider a replacement) but I am reliably advised that it shouldn’t be an interference fit. Once the inner roller is in place, the hub assembly and outer bearing can be installed, followed by the large washer and castellated nut (although don’t fit the split pin just yet). Give both sides of the brake disc a good going over with some brake cleaner to remove any wayward grease and re-attach the brake caliper (don’t forget to tighten the strut to vertical link bolts to the correct torque).
The end result…
The final step in the process is to adjust the bearing – tapered roller bearings should not have a pre-load (i.e. an axial force which is great enough to remove play in the bearing components), nor should they be too loose. The tightness of the hub nut determines the pre-load on the bearing – the aim is to find the ‘sweet spot’ in which the nut can be locked by the split pin that will allow a very small amount of detectable play. The threaded portion of the stub axle has two holes drilled through it at right angles, meaning there are 12 positions in which the split pin can lock the nut in any 360 degree revolution.
My technique, and there are many, is to temporarily fit the road wheel and then tighten the hub nut with a socket to ensure that all bearing parts and the rear grease seal are seated correctly. Next I back the nut off again until there is free play in the bearing and then very gradually re-tighten until the point at which all the play is removed. Finally I back the nut off until the next available hole for the split pin is available – in this position if the wheel is rocked from top to bottom I should just be able to feel some movement in the bearing (if there is still no movement detectable then I back off again to the next hole). Remember with taper roller bearings that a little bit too loose is generally better than a little bit too tight but, as a rule, if you can hear the movement then it’s probably too loose.
It can sometimes take a few attempts to get this right and the bearings should also be re-adjusted after a few miles to ensure that any additional play gained through the seating of the bearing components is accounted for (so make sure you order a couple more sets of split pins as they should not be re-used).
So that’s my update – both front wheel bearings are replaced. The next jobs on my list are not so small. Watch this space…