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Old 05-12-2018, 10:10 AM
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Diseasel300 Diseasel300 is offline
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Quote:
Originally Posted by Shern View Post
Stretched the overflow valve spring a couple weeks ago and I've since noticed my engine running slightly cooler. It's hovering a hair above 80, whereas previously it sat around 85. Unless I'm getting some new combustion efficiency and stepping on less pedal, I can't figure out a correlation.

Likely a total fluke, but anyone else experience this?
Unless the spring were so collapsed that you had no fuel pressure in the fuel rack and had extremely late injection timing as a result (you would have been seeing a good quantity of grey smoke that disappeared when you stretched the spring), it's all coincidental.

If you had enough fuel pressure in the rack to fill the injection elements to capacity prior to the stretch, then stretching the spring did nothing to the injection quantity or timing.

All things considered, assuming that the spring stretch helped in some way, diesels burn hotter with more fuel injected.
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