larger fuel return hoses/ caps on the 7.3 vs 6.9 IDI

86f2504x4

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I'm putting a 7.3 where a 6.9 once was. I would like everything to look as original as possible. I also already have a new 6.9 return kit in hand... Is there any reason not to use the smaller return hose/ caps for the 6.9 on the 7.3 engine?
 

IDIBRONCO

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To add a little more here, and this is just a guess, I'm guessing that they switched to the larger return lines when they eliminated the hard return line for the IP. There was more fuel going through the return lines now so it made sense to make them a little bit larger.
 

86f2504x4

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Thanks, folks... I had forgotten the early 7.3 had the small lines, and I hadn't studied the large line setup well enough to realize that the IP hard line was no longer there. Since I don't have a steel return line assembly available for the IP, I'll go with the later 1/4 inch plumbing.
 
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