Thursday, 18 April 2013

Getting head

My Bedford CF transporter was running sick. The old 2.3 was way down on power, usually sounded like it was running on three at best, and would backfire like a vegetarian full of Guinness. When I tried to adjust the tappets, I found that there wasn't enough adjustment left to put enough gap on the exhaust valves. Bugger - looks like I'm not the only one receding. 

I have another two Bedford CFs that aren't going to be seeing the road any time soon, neither of which will miss its cylinder head, so I picked the nearest and relieved it of its head, then took it along to a local engine place. A few days later I got back a lovely clean head with hardened valve seats and reamed guides..

On Sunday, after the Curborough jaunt, I started on the transporter. I drained the oil, removed the filter, then drained the radiator and removed it. You don't need to remove the radiator, but it gives you a bit of extra working space and gave me the opportunity to back-flush it for good measure.


Jeeez, the guy who painted this didn't believe in wasting any masking tape... Mind you, he did succeed in making a spray paint job look like the worst kind of brush-job. Not even a brush so much as a chewed twig. Anyway, once the radiator's out the way, access is pretty good.



After everything's disconnected, you just remove the cambelt and rocker cover, then the cam carrier lifts off wholesale... and if you're lucky, the followers stay on top of the valve stems and don't drop into the gravel.



Then you have to remove the exhaust manifold to get at the outer row of head bolts, but this was surprisingly easy. Then 10 head bolts let you take the head off complete with intake manifold. With the head on the bench the problem became pretty clear.



Not only were the valve seats receding, number 4 exhaust valve was missing a big chunk. Yeah, it really doesn't think much to this unleaded petrol lark. So, before opening the nice, new Payen head set, I thought I'd just check the new head lined up nicely on the block. Hmmm, it really wasn't keen. So with both heads on the bench I got the caliper and drill bits. Right, on the "new" head, the holes for the locating dowels were a tight fit on a 9.5mm drill bit, whereas on the bust head you could wiggle a 10mm drill bit in there. Maybe the dowel holes need drilling out? I wasn't going to risk my expensively-reconditioned head to me with a hand-held drill, so I popped over to James's where there's a massive drilling machine and somebody who knows how to use it.



This photo looks very cool and industrial, but doesn't convey the fact that it took at least an hour to get the head level and clamped to the bench before the drilling could commence. It took over an hour of build-up for about 90 seconds of drilling. We didn't draw any sexual comparisons there at all, of course.

The following evening, I went back to the unit with my freshly drilled head. First I took the intake manifold off the busted head, which would be very easy if it weren't for the thermostat housing which, naturally, is cheap, nasty alloy and the bolts corrode into it. I had to persuade the manifold with a blowtorch before it'd release one of the bolts.



You have to take the thermostat out of the way because, believe it or not, one of the bolts for the intake manifold lives behind it.



Yes, a steel bolt lives inside the water gallery, sealed by nothing more than a copper washer. Anyway, with the intake manifold to one side, I went to trial-fit the "new" head. Still it won't seat. Bugger. Back on the bench I looked at both heads side by side.... just a f**king minute. Out with the caliper. Yep, the dowel holes aren't in the same positions on both heads. They're only out by about 5mm, but the "new" head ain't going on the old dowels. Could I just forget the dowels? No, as it happens, because some of the water jacket steam holes don't line up either! Out with the caliper again, and off to check the engine on CF#2 that I'd relieved of its head. Bore x stroke = ... well bugger me bandy and call me Dorothy, it's a bastard 2.0. The DVLA think it's a 2.3, the guy who sold it to me said it was a 2.3, even the letter L cast into the block says it's a 2.3 (though L could also designate a 2.0, according to the Haynes manual. Thanks, Bedford). So, lesson learned - a 2.0 head doesn't fit on a 2.3 block.

Now what? I suppose I'll just have to see if CF#3 is a 2.3 and rob the head off that. Off I trot to CF#3, and set about removing the head. Now clearly this CF hasn't been buggered about with at all - the 53,000 miles looks to be genuine, no chopped wires, no cable ties, it's all factory. The exhaust manifold still has those bend-over locking tabs on the bolts, which is nice to see but unbending them took the thick end of an hour. Taking the rad out was a revelation - not only was the a truly diarrhoetic dribble of frightening brown sludge from the rad, but also I have never seen hoses or a thermostat housing quite so caked with that white crystalline gubbins.



Anyway, when the head finally came off, I tentatively explored its inner dimensions with the caliper. It was a 2.3, and seemed to be in very good order! I did a triumphant run around the yard,waving my arms about like a footballer's goal celebration and breaking into an impromptu chorus of the Goons' Ying Tong Song. No, I don't know where that came from either.

So I know have three headless engines. It's like Ozzy Osborne's been round. I'll be refitting head #3 this weekend, with a bit of luck. It also means that if anyone needs an expensively-reconditioned unleaded head for a slant-four Vauxhall/Bedford, I have one for sale. If you want the short engine to go with it, you can have it, but you'll have to be quick...

Eugene

Sunday, 14 April 2013

Sundays have mornings?!

Apparently, 9 o'clock appears twice on a Sunday, just like every other day! I know, it was a surprise to me too, but I got my rancid arse out of bed at an almost churchgoing hour this morning for a special trip out.

Near my workshop is Curborough Sprint track. It's a lovely little place, no grand facilities, but a pleasantly green place to go to watch a few interesting motors. Quite by chance, I happened to spot that they were running an "Introduction To Sprinting" day, where you could turn up in your road car and give it a go. Anything for a chuckle...


Sprinting falls into the same bracket as hillclimbing - it's solo against-the-clock competition. The day (and most of the events at Curborough) are run by the Shenstone and District Motor Club, who are a lovely bunch, and the whole place has a really nice vibe to it - a bit like Shakey County. There's nothing pretentious about the place, but there's a tea wagon, some half-decent bogs and not too many potholes. The track itself is racing-grade asphalt and really nicely prepared.

There were plenty of people there to try out this free trial offer, predictably loads of Minis, Super Seven-type things, Subarus and Evos, plus a couple of frighteningly fast Honda hatchbacks, but there were dozens of people just out for a giggle in the daily. The guy behind me had a Rover 820 on LPG, and one guy was there in a Mondeo and hadn't even bothered to take the bike rack off the roof. There was a nice Rover-powered Pop but I didn't see the owner and didn't see it on track.





We were all grouped in batches of about 12, and first off we were told all about sprinting, the hows, whens and wheres. Then we moved on to another guy who talked about all the paperwork you'd need -  sprinting requires an MSA Class B licence - and club membership. Then onto the scrutineer, who gave us a bit of gen about the rules and regs using a Volvo marked up with dayglo arrows! Very effective. One thing that struck me was that, in roadgoing Production class, you've got to run road treads from a prescribed list of manufacturers; no slicks, else you're bumped up to Modified and have to have a roll cage and all that jazz.



Some of the regular competitors were there in their road cars, and we got to jump in for a couple of trips around the track with someone who knows what they're doing. I got shown around by a single-seater racer in his Passat towcar - a diesel, automatic estate - and his sightseeing "lap", conducted whilst talking over his shoulder to the newbies in the back seat, was probably quicker than me in the Mustang at full chat.



Then you get to have a go in your own car with the instructor sat next to you. You sit at the startline until the light goes green, then tonk it up the long double-apex left, a shallow right, then into a sharp right-left called the Molehill, then a deceptively tight right-hand hairpin and there's a quarter-mile straight back to the finish line. In your head it takes about five seconds; in reality, the course record is something like 27 seconds, my instructor's tarmac rally Escort does it in 33, and I probably did it in about 50.



I had a couple of goes, and it was proper good fun. It also highlighted that the uprated springs and dampers have made a mighty difference. At a messy approach to the top hairpin, I approached too fast and was late turning in. The instructor said, "You're going to go off, you're going to go off... " then the car turned in beautifully, I powered it out of the corner and he just said, "Oh... okay then."

These sprints are damn good fun, but they ain't cheap. After your race licence and club membership, it's at least £70 per day for a sanctioned sprint meet, and you should get 4 runs - two practice, two timed - or more if it's not a packed schedule. That doesn't seem like a lot of track time, but I suppose £-per-minute it's not that different to drag racing... I did enquire about track days, and the secretary of the course told me about private "club test day" hire... but more about that later. The venue's website is www.curborough.co.uk if you fancy a gander.

Eugene