BMWs are Dumb

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The machine shop called to say that three valves were bent, and they were having trouble locating replacements. I quickly browsed all the German car part sites, and most of them didn’t have any intake valves in stock, but ECS tuning did. That should have been a warning sign, but I just ordered them with overnight shipping and figured it’d be fine.

They called shortly after delivery to let me know that the exhaust valve was correct, but the intake valve was the wrong size. After much searching, it turns out that the 6mm intake valves on the M42 were only used for one year, and they’re NLA from BMW. After much searching, it turns out that Rock Auto, of all places, actually has some aftermarket ones readily available. They don’t, of course, list the valve in a part search for my car, but once I managed to find the magic part number (RV1359), they appear. And unlike most sites, Rock Auto actually lists all the relevant dimenstions in a diagram, so I was able to be sure they were the right ones before ordering. Unfortunately, while RockAuto would happily ship next day, they said they wouldn’t ship for 3 days.

Luckily, they lied, and the shop got the valves on Friday, in time to return the head to me on Saturday.

Not good as new, but hopefully good enough:

A continued annoyance when reassembling this thing: BMW can’t be bothered to mark TDC (or anything else) on the M42 crank pulley. Just… why not? Yes, the stock flywheel has a hole that lines up with a hole in the case that you slot a tool through to lock the crank in TDC, but I don’t have a stock flywheel. And you still have to locate TDC to stick the tool in. This seems like the most basic thing you do to make an engine serviceable. I’m so over BMW. Problem solved for now:

I got it mostly bolted together on Saturday evening (at least everything with sealant on it) so it could cure overnight. Finished up Sunday morning. Cranked it over to prime the oil system, got 30PSI of oil pressure on the starter motor. Then flipped on the fuel pumps and hopped out to leak-check the fuel system.

I had a geyser of fuel spraying from one of the braided stainless hoses on the firewall. It had leaked there once before, and tightening the connector fixed it. It did not this time.

I pulled the fuel hose, cut an inch off the end and reattached the AN fitting. An even bigger leak. Curious how I bungled that so badly, I did it again, and it leaked again. This time when I pulled it off, I noticed the rubber hose inside was cracked several inches. I cut it off past where it was cracked, reattached the connectors and tried yet again. This time the geyser came from the middle of the hose. At this point, I’d probably been screwing around with this hose for 3 hours, I was drenched in fuel and furious.

After looking it up, apparently it’s normal for this stainless braided rubber fuel hose to disintegrate after just 5 years? This stuff is probably as old as the original build (2007), but what the hell? OEM rubber fuel lines often last 40 years with no problems! I think the fact that it spent a year drying out when the engine was disconnected is probably the biggest problem.

Anyway, AN-sized braided fuel line isn’t something that auto parts stores seem to have in stock. I ordered a bunch of replacement stuff from Amazon, this time PTFE (teflon) which supposedly lasts longer than the rubber. But it won’t get here until tomorrow. And registration for Rally Colorado ended last night.

So, I went ahead and registered even though I have no idea the car even runs, much less drives. I have 9 days. I’m sure it’ll be fine?

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