Broken Down in N. California..north of Eureka
GF was driving our Class C, 1999, E350, V10, 22' and as we were headed downhill, she apparently pulled the shift lever down into first instead of second and the engine made a loud screaming bang. We c...
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It is very possible you locked em up when that happened. Also very possible is you jumped some teeth on the timing chain, hence the very poor running. If it doesn't sound like a blender full of rocks and there's no lake of oil on the ground, you probably escaped catastrophic engine failure.
The timing chain can jump in this situation because at cruise RPM the timing chain tensioner isn't holdings very much pressure (it's hydraulic from the engine oil). Under high RPMs the chain needs much more pressure to hold it tight, especially with normal wear on the chain guides. A sudden extreme change in RPMs means the chain is flailing outward but the chain tensioner needs a second or so to build more pressure (especially on an older motor with oil deposits making all the teeny passages even smaller).
Re-timing the motor isn't hard, but it's a lot of labor to pull everything off the front of the motor to get to the chain. And you'll want to have a leak down test first to make sure no valves were damaged. A compression test might give a false fail result if the timing is too far off. It also requires a special balance-shaft removal tool which few shops have, since v10s rarely have to be opened up. (I had my timing chain replaced preventativey around 400,000 miles because it had some cold start chain slap from loosening up with age)
The timing chain can jump in this situation because at cruise RPM the timing chain tensioner isn't holdings very much pressure (it's hydraulic from the engine oil). Under high RPMs the chain needs much more pressure to hold it tight, especially with normal wear on the chain guides. A sudden extreme change in RPMs means the chain is flailing outward but the chain tensioner needs a second or so to build more pressure (especially on an older motor with oil deposits making all the teeny passages even smaller).
Re-timing the motor isn't hard, but it's a lot of labor to pull everything off the front of the motor to get to the chain. And you'll want to have a leak down test first to make sure no valves were damaged. A compression test might give a false fail result if the timing is too far off. It also requires a special balance-shaft removal tool which few shops have, since v10s rarely have to be opened up. (I had my timing chain replaced preventativey around 400,000 miles because it had some cold start chain slap from loosening up with age)
