Having driven 30,000 miles in the fifteen years since the last rebuild (by Ian Bancroft) it was time to give BBM69 a Major Service. A short list of snags has accumulated over the years and as we are planning a trip to Brittany, this seemed a good time to sort them out.
Number one was to tighten the steering wheel nut properly. Every year the nut has been tightened by withdrawing the centre tube 10cm and using an open ended spanner. This was never very successful. This time it was intended to take the tube out completely and tighten the nut with a socket, fix it for good. Another thing was to add a spacer at the top of the tube to stop it rattling. It had a piece of leather round it but that seemed ineffective.
The petrol gauge has become more erratic as time goes by so that needs fixing. Different gauges have been tried but all seem to give different readings.
The flasher units need to be checked as they are getting corroded and are not as bright as they were.
The backlash in the back axle is excessive, giving noise on overrun, so that will be looked at.
Both seat squabs need looking at to have some holes patched.
The double front shock absorbers need adjusting.
A spare gear lever is carried on long journeys, is it the correct one for a four speed Ruby box? That needs to be checked.
Two core plugs in the head are weeping so they will need to be replaced.
No doubt other items will crop up as the Annual Service and Regular Attentions are carried out. See below.
Having disconnected the leads at the junction box the centre tube was removed complete with cable, this raised another snag, the cover on the cable had worn through. I obtained some four core cable and replaced it. Some tape was wrapped round the tube, at the top, to prevent rattles, this replaces a worn leather bush. After this job the flashers were twice as bright! There must have been a bad connection somewhere. At the same time the pinch bolt that clamps the central tube was replaced with one with a deeper head to make it easier to get a spanner on it.
Steering wheel connections
Having drained the radiator and block the two core plugs were drilled at 1/4” and levered out with a screwdriver. The seats were cleaned out and new core plugs fitted. They were seated in gasket compound. The plugs were expanded with one good blow to a drift slightly smaller than the plug, placed centrally to it.
Next job tackled was to check the front brakes and steering. The hubs and the back plates were removed. To make them easier to work on.
Both nearside and offside brake cams and bushes were worn. I found that the replacement bushes were oversize. I pressed one in and it burst the old aluminium housing. Luckily a spare was to hand. I measured the bush and housing and found the interference fit was over five thousand of an inch. Too much for me. The housing was left as it was and the outside diameter of the bush reduced to give a fit of plus 2/3 thou. They were then pressed in. The internal diameter of the bushes then needed opening out to allow the new cams to move freely. This was tackled with a sharp drill then cleaned up with 700 grade wet and dry to polish. New pins were fitted. All the moving brake components were lubricated with copper grease before assembly.
TWO WORN CAM SPINDLES
The brake cams and bushes in the rear axle were fine. They had been replaced when the back axle was rebuilt.
Having finished and having refitted the hubs I thought I would have a look at the front brake cable to see if it was wearing. The cable looked fine but the swivel fork that holds the quadrant did not. The threaded portion has been bent at some time and does not look fit for purpose. This is a Mission Critical, (in the modern parlance), item. If it brakes all front braking will be lost. The one spare that was available looks just as bad.
A new threaded portion was welded in to the better fork. How the part got bent is a mystery. Nothing looks close enough for it to foul on, perhaps it has been hit by something on the road, we have been over some rough tracks. Having looked through the parts book, 1406D, it became apparent that the front brake rope swivel, as they call it, was an after market product and did not have the bush in the centre as it should. Having thought about it the after market swivel has been retained. It turns out it is easier to adjust the brakes using the nut and lock nut.
Setting up the brakes was completed by adjusting the shoes at each wheel. BBM has each wheel set up with the least clicks back to free the brakes. Other information says always take three click back, the choice is yours. Having set up as described a trial run was carried out. The car pulled markedly to the nearside. The nearside brake was let off one click and the offside taken up one click. The brake lever return springs do not seem to be doing the job required. They are new ones that have been on the shelf for some time. I sorted through all my springs and fitted the best ones. New springs may be made from piano wire. After a run with brakes in use the heat of the drums was as follows:
NS rear hot
NS front cool
OS rear warm
OS front warm
The NS rear was backed off one click. Having driven 30 miles the brakes are all cool, Brakes were hardly used. Next is to check again down hill.
The track rod was removed complete, having loosened the securing nuts two or three threads they were started moving by drifting them out with a lump of lead. This was repeated until the levers could be withdrawn. Once removed it was clear that there was too much play in the pins and bushes. On closer inspection the bushes were found to be fine, but the pins were were slightly worn, these were replaced. After this no horizontal movement was evident. The clevis pin slot on the new pins were shallower than the original pins so the clevis pins were filed down to give a good fit. The track rod was refitted with new lock washers.
The drag link connections were inspected and found to be satisfactory, I did replace the front side tube spring as it was shorter than the new one.
I then started to look at the problem with the petrol gauge. Having some spare gauges and a spare sender I set them up in the workshop. They worked as they should do, zero to full. I then slaved the spare sender in the circuit on the car. The gauge read under as it has been for some time. I then fitted the spare gauge and it read fine with the spare sender so I have re-connected it to the tank. I will not know for sure until the tank is filled again. After filling the tank it is clear the problem has not gone away. The tank sender may well have to be replaced. But not before the trip to France. I have since fitted a replacement gauge that is accurate, but sticks at zero occasionally! Some you win some you lose. I have since found out that the empty and full stops get sticky, I have sleeved them both with wire insulation and they are now fine,
Crown wheel and pinion backlash
The rear axle backlash has been checked and decreased. This was measured at the hardy spicer it needs to be 1/16 of an inch at at 7 inches from the center of the joint. It has reduced the noise on gear change and over run.
Setting up the backlash, in this case off the car but the same procedure works on the car. the Ruby has a hatch over the rear hardy spicer coupling
Spare gear stick
The spare gear stick has been tried and tested, it is fine and now lives behind the rear seat with the spare half shaft and head gasket.
Body rot check
Having inspected the body work, an area in the “boot” needed repainting. The luggage rack was removed and the lower part of the ‘boot’ painted after treating the bare patches with red lead. The gaps in the boot were sealed with tape, a lot of dust and gravel has been collecting in the bottom.
The opportunity was taken to tidy up the cables that run through the area.
The two front flasher units were stripped and both found to be very corroded. New ones have been fitted and the cable connections checked, they were also painted with preservative. The rear units were fine. I have since fitted electronic flasher relays, they have made the flashing rate and start up much better.. I did have to fit a suppressed HT though to prevent interference.
Having completed the service to my satisfaction I asked my local garage to check BBM over. It is difficult to be sure all bearings, joints and fastenings are serviceable and secure when crawling about under the car. They agreed enthusiastically and indeed did it free of charge! So good having a small helpful garage on the doorstep. They found all in order.
Spare parts list.
Annual service form.
The front shock absorbers were set using a torque wrench.
Road springs were lubricated with graphited penetrating oil.
Back axle, gearbox and engine oil were drained and replaced with clean oil.
New spark plugs were fitted.
New points were fitted.
I still need to sort out the leather seat squabs!
While in Brittany on holiday the pressure release valve (see below) in the radiator header tank jammed shut. (probably as I had used radweld). Pressure built up and blew out one of the core plugs I had fitted. Lucky really as the radiator may have split! I left the cap loose after replacing the core plug.