Monday
The BAR manager called. He said that my SPCNS had been approved and that I’d have to make an appointment for a follow on inspection. Also to make sure that I have a PCV valve fitted (which I do).
Friday
I made the follow on appointment only after I got the diff seal fixed – its set for 7:20am on August 15th (Thursday).
I spent a couple of hours researching the seal in the internet. Turns out I need a different seal part number = 33-10-7-505-603. It appears this seal is used on more obscure european BMW models, so its not common in the US. Here’s the spec on the 2 seals:
p/n OD ID width
33-10-7-505-603 78mm 44mm 10mm <—this is the one I need.
33-10-7-505-604 90mm 44mm 10mm
I had mentioned earlier that I’d seen oil coming from the dif, so I had a closer look and it appears to be coming from the right side shaft seal. Here’s a picture, but you can’t see much.
Differential oil seal failure
Talked to Jon at Caterham & he told me that the differential is made by BMW for a series 1 and the fastest way to get one would be to go to a BMW dealership. So I ordered a couple of seals online from a BMW dealer in Phoenix. In the meantme, I topped up the oil level in the diff, it seemed to take a lot – but it was with a squeeze bottle & 3/8″ tube. Part number on the diff is 7514992 – this is not recognized on the BMW website, but when searching on google, it recognizes it as a BMW differential.
Hub hanging on paracord
The seals arrived this afternoon. I inspected one and it looked the same and the ID fitted exactly on the (throw-away) shaft that I had previously removed from the diff when I installed the drive shafts.
So, about 6pm I set about replacing the seal. Removed the RR wheel, then stripped off the disk caliper assembly & hung it by a bungee cord. Disconnected the anti-roll bar attachment and then undid the 4 bolts holding the de-dion ear to the de-dion tube. I hung the hub assembly by a rope from the roll over bar.
The driveshaft slid out of the diff with a slight tug. I inspected the seal, but saw nothing major wrong with it. Anyway, I removed the seal (destroying it in the process) – these things don’t come out easy!
I went to fit the new one – but the outside diameter was too big – see picture. New one on left, old one on right.
Oil seal mismatch
The BMW part number for the seal is 33-10-7-505-604. This part is supposed to fit most/all 2012 BMW series 1, and specifically the 128i. I guess they use a different differential to mine.
So my car is sitting on jack-stands awaiting a new seal – I sent an email to Jon to order one, he has none in stock – it’ll have to come from Caterham UK, which may take a while.
I finally connected with the manager at BAR. He told me that they were waiting on one inspector to return back to work this Thursday. This inspector needs to look over my paperwork. He said he’d call me back on Monday or Tuesday next week.
Found this butterfly on the front grill after the Sacramento trip.
Butterfly
Wednesday
While I was optimistic that I’d found a fix for the speedo, it started mis-behaving again.
Thursday
Dot & I drove to Sacramento for the smog referee inspection. We took I80, because we wanted to get there in plenty of time.
Driving I80 to Sacramento. Note the temp gauge – not good.
Dot, not too happy in a helmet
Dave the driver
Got my helmet on
We found the referee office at the American River college fairly easily, 30 minutes early, so we went out to McD’s for some breakfast & coffee.
I called the referee phone number in the office as instructed and he showed up a few minutes later with his assistant. He wanted to see the paperwork (DMV, CHP, receipts etc.) which I provided. He wanted to see the VIN. Then he took lots of pictures and excused himself for 45 minutes to inspect the paperwork and make copies. When he finally came back, he said they needed more time to review the information and provided a letter stating that I need to reschedule another appointment at a later date. I was shocked, no reason given, no advice on whether the car was plumbed OK, no defective items pointed out. So a day wasted and a 250 mile round trip for nothing. Bummer.
Referee at work
So we left and headed for Placerville, where we met up with my old buddy Sal Dioro at Starbucks and spent an hour or so catching up.
We then headed home via Mormon Emigrant trail to Hwy 88, on to South Lake Tahoe & then home on Hwy 89 along Tahoe West shore. The first 2 roads had almost no traffinc and were windy in places, so it was a great drive back. The traffic started as we got close to South Lake Tahoe and the fun was mostly over.
Now, most of this time the speedo had gone from intermmittant to non functional (pegged at 0). So, think, think – it only goes wrong when it gets hot. So to try and prove this, after we got home, I waited a couple of hours and set out at 7pm – speedo working fine!
Friday
I slept on it and decided to go out in the heat of the day armed with a can of freeze spray (used for diagnosing electonics circuits).
This afternoon (hottest part of the day), I went for a drive up to Cisco Grove on old Hwy 40. As usual, when cold the speedo worked fine and continued to do so for about 25 miles, then started to go intermittent. I drove another 5 miles to make sure it was truly intermittent, then pulled over and thoroughly doused the speedo with freeze spray. Turned around to head home and the speedo was working fine, for about 6 or 7 minutes, then it started to go intermittent. More freeze spray, and its OK again. Repeated 4 or 5 times on the way home.
So I think, I’ve proven that there is some heat sensitive component in the speedo, that is failing when it gets to a certain temperature. This is a typical IC failure symptom, as I’ve used freeze spray to identify faulty components on circuit boards in the past.
Monday
I had gotten feedback on the speedo issue from Jon at Caterham in Denver. He thought is was an electrical connection problem & asked me to check all connectors and check that I had a good ground.
I checked, connections were good. I installed a 2nd ground strap from the battery to the chassis.
Tuesday
This morning, when I set out, first time of the day and cruised slowly to the freeway & slowly accelerate up to 70mph, everything seems fine – the speedo indicates true speed & no flickering. I drive 3 miles to downtown Truckee & do some errands. On the return trip, cruising 1/2 mile to freeway, speedo OK. On the entrance to freeway, I punch it, getting to 70mph quickly, and the speedo is intermittent (flickering around the 20mph range). On leaving the freeway, stopping, then driving at slower speeds and lightly accelerating the speedo seems to perform better, but I’m still seeing some flickering.
More feedback from Jon: ” It really sounds like a loose or partially broken connector somewhere.
You might want to try to isolate it by removing the speedo from the dash and then reconnecting it underneath the dash so you can hold it in your hand. Find a safe place and drive the car and move the connector, shake the speedo, etc to see if the problem is there. I have found a badly spliced wire in the little rectangular plugs on the speedo before”.
So, I unplugged & removed the speedo, checked the connectors and plugged it back in. I checked the speedo casing and measured the resistance to ground and got an infinite reading. So the casing is not connected to the ground wire on the plug. To be sure, after I installed the speedo back in the panel, I ran a crocidile clip cable from the speedo casing to ground.
Wednesday
Had a 7am appointment with the dentist in Tahoe City, 20 miles each way. It was cold, next time I’ll wear gloves as well as a jacket, & maybe a scarf. The speedo behaved perfectly on outbound & return trips. Noting that I drove smoothly without violent accelerations.
I checked that the heater works, not too hot, but when I turned the fan on, the engine temp guage went down. Which may mean I’m over-cooled.
I noticed a few drops of oil on the garage floor (again – I’d seen this before as well). Appears to be coming from the diff. I wonder if this is due to it being full just after I installed it and the excess oil had not fully drained to the level when I re-fitted the bung.
Tomorrow, I have to drive to Sacramento to have the smog referee inspection. This will be the first long drive. We’ll see how we get on.
Saturday
Alex found a 1977 Chevy C10 truck and bought it to restore. We drove him to Gardnerville to pick it up.
Sunday
Checked out Alex’s truck this morning. First thing to do will be to install a full exhaust system with catalytic converters , we’ll need 2 of them as the V8 engine has 4 headers on either side. What a contrast to the 7, I didn’t need to jack it up to climb underneath. I sat in Alex’s truck parked right behind my 7….I couldn’t see the 7 at all! So, I’m going to have to be carefull driving next to big trucks. See pictures…
The 7 from the underside of Alex’ truck
Objects closer appear bigger than they really are
Contrasts
Little car
Friday 5th July
I adjusted the speedo sensor yet again. Won’t bore you with details.
Wednesday 10 July evening
Took the car out for a drive up Mt. Rose. It was a fun drive once I got to Mt. Rose highway itself, but there was lots of traffic in Kings Beach, Crystal Bay and the road to Incline vilage. Mt. Rose highway has lots of bends & hairpins which was the best part.
Mt. Rose highway scenic overlook (Lake Tahoe in background)
On the way back the speedo started going intermittant again, at one point it was showing 70mph when I was doing 50mph, then when I stopped at a traffic light, speed indicated was 20mph. So, I’m beginning to think the problem may be the speedometer itself.
On the way home driving past Nothstar, there was a turnoff to the Ritz Carlton. This is a road from hwy 267 to the hotel at the Nortstar mid mountain camp. It was a blast, up & down with tight corners and virtually no traffic.
Wednesday
Went out early morning to get some coffee & bagels with Dot. Noticed that the speedo was starting to go intermittent again.
After breakfast, went out to adjust the driving seat for a better fit. It needs to move back a little. Took the seat out, & noted where the seat adjustment was getting hung up at the back of the RH runner. Also the RH seat belt mount was in the rear mount hole rather than the front one (this could have caused some seat movement blocking). Moved the seat belt to the forward mounting hole. Drilled 4 new seat mounting holes at 2″ back from the existing holes. Used 1.5″ wide x 6″ metal re-enforcement at each hole to provide some support rear of the hole to potentially assist rearward movement of the seat, hot glued in place to locate them while the seat went back in. Re-fitted the seat, it went in much easier than the first time in April. Achieved getting the seat back about 1.5″, which is a much better sitting position. (note, the picture was taken several months later when I had to take the seat out).
Seat mounting holes
Bolted mat fixing
Got some double-sided tape to glue down the driver side mat, which was shifting forward under the pressure of my feet & getting in the way.
In retrospect this did not work well. The glue eventually started giving way and making a sticky mess. I finally removed the glue & cleaned up, then fixed the mat in place with bolts passing through an aluminum rail, the mat and the floor. (picture at right).
Dot had bought me some barefoot sneakers from REI, these were much better for driving but still having some trouble overlapping pedals – I could definitely use an extra 2″ of width in the pedal box. Tried bare-footing to feel what foot position is optimum to avoid hitting the gas when braking. It appears that my right heel needs to come further back when braking to avoid my right little toe hitting the gas pedal. I’m getting overlap of my feet when clutching & braking together – not a problem if my left foot goes down on the clutch first & the right big toe overlapping (the left big toe) when on the brake. Clearly my feet need to be at least 1″ less wide than they are.
Put some weather stripping at the back of the nose where the bonnet fits ( there was some abrasive marks there).
Before adjustment
After adjustment
Finally adjusted the speedo sensor, it initially looked like it wanted to go in 1/4 turn, but on tightening, the sensor led was on all the time- so I adjusted back, ending up with the sensor coming out a little less than1/4 turn. See the before and after pictures and the red painted line on the sensor.
Went out for a test drive. Speedo was normal (no intermitancy). Seating position much better. I noticed that when stopped with the engine idling the front bonnet rattles where I had installed the weather stripping – I’ll have to investigate a better solution.
Dave's 7 build 