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IO360 A1A FUEL LINE ROUTING

ERJDriver

Well Known Member
Good morning,

Just got my engine back from aerosport. Something is different with the fuel divider for sure.

My routing before was was fuel servo, then fuel line out of servo ran aft then came up and through the aft baffle to the fuel divider.


Now it looks like it goes from the fuel servo up through the inner baffle between 1 and 3 to the fuel divider.


How are you alls routed? Wondering if mine before was wrong/vans way/ or just the builder doing his own thing
 
Mine comes up from the servo through the intercylinder baffle between 1 & 3 to the fuel divider.
 
The new configuration is far more common, though the install on my 6 goes back and through the rear baffle. Unsure about pros and cons, but believe the longer line allows more heat to be absorbed by the fuel and will take longer to flush out after a heat soak.
 
The "stock" configuration from Lycoming, with a front mounted - horizontal sump is to route the fuel line from the top of the servo up through the inter-cylinder baffle located between #1 and #3. It's been this way for at least 25 years (looking through old pictures).

A long fuel line run isn't "wrong", just more prone to vapor locks, messy wet fuel soaked injectors after shutdown, hard hot starts...

EDIT: updated to include configuration specific information. Rumor has it that Lycoming produced the same configuration of the same model engine twice -- but that's just a rumor, not borne out in fact.
 
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Exhaust and servo type may dictate routing. If you have the Vetterman cross over, you may not have the clearance to go between the inter cylinder baffles.
Mine runs back and through the rear. I do not, and never have had, hot start issues. Make it as short as possible if you go that direction.
 
Exhaust and servo type may dictate routing. If you have the Vetterman cross over, you may not have the clearance to go between the inter cylinder baffles.
Mine runs back and through the rear. I do not, and never have had, hot start issues. Make it as short as possible if you go that direction.
Hmm...No issue with Vetterman X-over on my IO-360-A1B6's (AV). Perhaps the PV's ( -B1/M1B ) are tighter.

Did you route to the "top" or "bottom" of the servo body?
 
Hmm...No issue with Vetterman X-over on my IO-360-A1B6's (AV). Perhaps the PV's ( -B1/M1B ) are tighter.

Did you route to the "top" or "bottom" of the servo body?
Sorry, I have a Silverhawk Vertical induction. The port is out the back. Not common.
 
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