Honda Pilot - Honda Pilot Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
29 Posts
Discussion Starter · #1 ·
This is to document engine replacement in a 2009 Pilot AWD with a standard J35Z4 replaced with a 2012 Odyssey J35Z8 engine. (If you want to dork-out, here are the vins: 2009 pilot vin: 5FNYF48949B025834 2012 Odyssey vin: 5FNRL5H41CB103761)

Firstly, I'm speaking from ~35 years or wrenching & machining experience both as a profession and as a hobby. Though I have a lot of hand tools, I no longer have a lift or anything fancy that makes this otherwise impractical for others.

Though a z4 for z4 engine may be ideal, it is not the only option, however I was unable to find a suitable replacement (<100,000 miles, & <$2500), so under advice from other mechanics, I went with a z8 engine from a 2012 Odyssey (85K miles, $2200 delivered, 9 month warranty).

In a nutshell: the swap works and works great. Nothing to worry about- just practice good wrenching and error to using the Z4 parts when there are differences.

Here are some notes:
*Use the z4 engine wiring harness
*Use the z4 crankshaft timing gear (z8 has different marks!)
*Can use either serpentine belt tensioner (newer style tensions is so much nicer to use than the older one...)
*Oil level sensor above the oil pan is in a different location by about 1"- Z4 wires easily reach but may need to re-seat them in the zip tied bracket. (this is on the firewall side of the engine, behind the motor mount). All other oil pressure sensors are same pressure and identical etc.
*all bolts bolt-up otherwise (flex plate, bell housing/tranny, engine mounts, oil pan, etc)
**flex-plate bolts are not equally spaced- may need to try it a few times until all 8 bolts line up.
*engine mounts- heads'up: they are different, and the odyssey didn't use the same holes. I had to chase the holes (12 x 1.25) as they were a bit grungy, yet were tapped otherwise.
*same injectors (reseal while you can!)
*z8 exhaust and intake manifolds are the same, including attached electronics
*Catalytic converters are different! So stick with the z4's.
*same water pump, and timing belt kit between the two
*cooling manifold & t-stat are same. Heater hoses from TB to T are the same, but T to car are unique
*check part #s- make sure the throttle body, VCC, etc are the same. My donor engine (z8) had identical parts.
*z4 ECM works with the z8 engine without issues.
*vacuum manifold heater & transmission vents are different- stick with the z4.
*cams: The cams are different with the z8 being more aggressive at higher rpms that the z4. No different with respect to the swap.
*need to have it re-aligned after this procedure.

Around town driving appears to be identical, however, acceleration (like at a freeway on-ramp or passing on a 2-lane road) is noticeably quicker with the the z8.

Notes for the procedure- I followed the factory service manual, however I did not remove the radiator or fans, nor steering wheel, but I did anchor the steering wheel so it didn't turn once the steering rack was removed. Using a engine hoist, lower the complete engine, transmission and subframe in one package- I lowered it onto long 2x4s, allowing it to be easily slid out from under the vehicle. Then carefully raise the car- I used large 20-ton jack-stands and 6x12 wooden blocks (headers end cuts) as backup. You'll need to raise the car about 40". Once raised, slide the engine out, and then lower the car (for safety!) Reverse the procedure to install. Feel free to email me any questions.

On a side-note, this is a great opportunity to freshen the engine mounts and suspension, and replace all fluids.

-Matt
North Idaho
 

·
Registered
Joined
·
9,519 Posts
This is to document engine replacement in a 2009 Pilot AWD with a standard J35Z4 replaced with a 2012 Odyssey J35Z8 engine. (If you want to dork-out, here are the vins: 2009 pilot vin: 5FNYF48949B025834 2012 Odyssey vin: 5FNRL5H41CB103761)

Firstly, I'm speaking from ~35 years or wrenching & machining experience both as a profession and as a hobby. Though I have a lot of hand tools, I no longer have a lift or anything fancy that makes this otherwise impractical for others.

Though a z4 for z4 engine may be ideal, it is not the only option, however I was unable to find a suitable replacement (<100,000 miles, & <$2500), so under advice from other mechanics, I went with a z8 engine from a 2012 Odyssey (85K miles, $2200 delivered, 9 month warranty).

In a nutshell: the swap works and works great. Nothing to worry about- just practice good wrenching and error to using the Z4 parts when there are differences.

Here are some notes:
*Use the z4 engine wiring harness
*Use the z4 crankshaft timing gear (z8 has different marks!)
*Can use either serpentine belt tensioner (newer style tensions is so much nicer to use than the older one...)
*Oil level sensor above the oil pan is in a different location by about 1"- Z4 wires easily reach but may need to re-seat them in the zip tied bracket. (this is on the firewall side of the engine, behind the motor mount). All other oil pressure sensors are same pressure and identical etc.
*all bolts bolt-up otherwise (flex plate, bell housing/tranny, engine mounts, oil pan, etc)
**flex-plate bolts are not equally spaced- may need to try it a few times until all 8 bolts line up.
*engine mounts- heads'up: they are different, and the odyssey didn't use the same holes. I had to chase the holes (12 x 1.25) as they were a bit grungy, yet were tapped otherwise.
*same injectors (reseal while you can!)
*z8 exhaust and intake manifolds are the same, including attached electronics
*Catalytic converters are different! So stick with the z4's.
*same water pump, and timing belt kit between the two
*cooling manifold & t-stat are same. Heater hoses from TB to T are the same, but T to car are unique
*check part #s- make sure the throttle body, VCC, etc are the same. My donor engine (z8) had identical parts.
*z4 ECM works with the z8 engine without issues.
*vacuum manifold heater & transmission vents are different- stick with the z4.
*cams: The cams are different with the z8 being more aggressive at higher rpms that the z4. No different with respect to the swap.
*need to have it re-aligned after this procedure.

Around town driving appears to be identical, however, acceleration (like at a freeway on-ramp or passing on a 2-lane road) is noticeably quicker with the the z8.

Notes for the procedure- I followed the factory service manual, however I did not remove the radiator or fans, nor steering wheel, but I did anchor the steering wheel so it didn't turn once the steering rack was removed. Using a engine hoist, lower the complete engine, transmission and subframe in one package- I lowered it onto long 2x4s, allowing it to be easily slid out from under the vehicle. Then carefully raise the car- I used large 20-ton jack-stands and 6x12 wooden blocks (headers end cuts) as backup. You'll need to raise the car about 40". Once raised, slide the engine out, and then lower the car (for safety!) Reverse the procedure to install. Feel free to email me any questions.

On a side-note, this is a great opportunity to freshen the engine mounts and suspension, and replace all fluids.

-Matt
North Idaho
Thanks for the interesting read.
Any photo during the process?
 

·
Registered
Joined
·
29 Posts
Discussion Starter · #5 ·
Oh yeah here is why it was swapped. See the stuff in the oil ? The Ian has about 1/2” of metal particles: three spun main bearings Two burned valves too. 220k miles.
139437
 
1 - 5 of 5 Posts
Top