what are the common problems with a 1985 bmw 635csi?

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Hey there! Great question about the 1985 BMW 635CSi. The E24 "Shark Nose" is a fantastic grand tourer, but at 40+ years old, it does have some common trouble spots. Here's what to watch out for:

**Electrical Gremlins**
The E24's electronics are a bit complex for its era. The **speedometer/odometer** is notorious—those tiny gears in the cluster crack with age (like the one on this car). **Sunroof motors and switches** also get flaky (also noted on this listing), and power window regulators and central locking can act up. Aging wiring harnesses cause all sorts of random issues.

**Engine & Drivetrain**
The M30B34 3.4L inline-six is famously bulletproof, but keep an eye on:
- The **timing chain tensioner**—can leak or rattle on startup
- **CIS-Jetronic fuel injection**—prone to air leaks and warm-up regulator issues
- **Valve adjustments**—solid lifters need adjustment every ~15k miles
- General age-related rubber (hoses, seals, mounts) degrading after 40 years
- The **3-speed automatic** is usually robust, but deferred fluid changes aren't kind to it

**Bodywork & Rust**
The rear of the car is particularly vulnerable:
- **Rear wheel arches and fender wells** (this car shows rust here—very common)
- Rocker panels, jacking points, and floor pans
- Door bottoms and trunk floor where water collects
- **Clearcoat failure** and UV damage (also noted on this example)

**Interior**
- **Dashboard cracking** is almost universal—this one's noted as having "typical cracks"
- A/C systems often need an R-12 to R-134a conversion (this one needs service)

The good news? This particular Florida car has a solid underbody and that strong M30 engine—two of the most expensive things to fix are already in good shape! At $9,995, it's priced appropriately as a project where the common issues are cosmetic and electrical rather than structural.

Want me to look for similar E24s in better condition, or do you have questions about addressing any of these specific issues?

Lot 692: 1985 BMW 635CSi

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Lot 692: 1985 BMW 635CSi

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