Gen II to Gen I engine transplant

[RadioHowie]

Is it feasible?

I know the fueling system is entirely different, but would the Gen I throttle bodies work on a Gen II?

And would there be other issues, such as coolant plumbing, electronic connections, including ECU sensors.

Anyone with a good opinion?

Wild *** Guesses?

 

[Toecutter]

Wild *** Guesses?

What could go wrong?

 

[ponyfool]

Having had the engine out of my 2nd gen, I would primarily be worried about motor mount locations. I believe the engine is a part of the stability of the FJR's frame.

 

[SkooterG]

Why?

 

[C&C]

Same engine, different electronics, right??????????

 

[ionbeam]

I looked into a Gen II replacement but due to sensors, a little plumbing and other little details I decided not to go that route. The most significant known issue is the VSS sensor is missing from the Gen II engine, the motor mounts are an unknown (to me). As a bonus you get a higher output stator, but give some back when you need a Gen II R/R and it won't fit the Gen I location.

The TB rack and exhaust will hook right up.

The things I learned when searching for a used engine.

Things I learned about searching for a VIN 1.

VIN 2

VIN Decoding web site: Here.

Yamaha does not sell a complete engine, you can only buy parts. Yamaha does not associate an engine block number with a frame or VIN number.

 

[RadioHowie]

Why?

Dead Gen I. Possible good price on late model, low mileage Gen II replacement.

Is that the "why" of which you asked?

 

[RTSR1/FJR]

Why?

Dead Gen I. Possible good price on late model, low mileage Gen II replacement.

Is that the "why" of which you asked?

From what I've learned, Gen II will fit phycically as long as you use Gen I mounts. FI will interchange. Only question is the VSS as mentioned. There is a plug on the GenII where the VSS was on the Gen I. Just don't know if there is anything behind it to trigger the VSS. I compared everything from my buddy's '06 to my '03.

 

[Geezer]

How about you just swap the head from the Gen 2 onto your Gen 1?

 

[RadioHowie]

How about you just swap the head from the Gen 2 onto your Gen 1?

That is a possibility, but what if there's bottom-end, piston or rod damage?

Then a 1 to 1 swap makes a lot more sense, if it would work.

 

[ionbeam]

How about you just swap the head from the Gen 2 onto your Gen 1?

That is a possibility, but what if there's bottom-end, piston or rod damage?

Then a 1 to 1 swap makes a lot more sense, if it would work.

Having hammered my engine just about as bad as can be, I can say that after TWO engine removals to inspect the reciprocating parts as well as the crank shaft no damage was found. It would be a pretty good gamble to anticipate the lower engine parts are ok. We did find stuck piston rings but that most likely was independent of my valve 'incident'.

The cylinder head can be swapped with the engine in the frame, a major benefit. It's tight, but can be done. My cylinder head had one bolt, front, center that had to be drilled out and that was a b!tch to do. After all that work we then discovered that my engine was going to have to come out anyway.

 

[RadioHowie]

How about you just swap the head from the Gen 2 onto your Gen 1?

That is a possibility, but what if there's bottom-end, piston or rod damage?

Then a 1 to 1 swap makes a lot more sense, if it would work.

Having hammered my engine just about as bad as can be, I can say that after TWO engine removals to inspect the reciprocating parts as well as the crank shaft no damage was found. It would be a pretty good gamble to anticipate the lower engine parts are ok. We did find stuck piston rings but that most likely was independent of my valve 'incident'.

The cylinder head can be swapped with the engine in the frame, a major benefit. It's tight, but can be done. My cylinder head had one bolt, front, center that had to be drilled out and that was a b!tch to do.

Alan,

Glad you hopped back in on this. It certainly gives me an option I didn't have yesterday.

Just for hypotheticals, if you had to re-live this issue, would you feel comfortable just swapping heads?

RH

 

[ionbeam]

Just for hypotheticals, if you had to re-live this issue, would you feel comfortable just swapping heads?

My engine situation was not the same as yours, my cam chain was off the crank gear when we opened the cover. There was clear evidence that the pistons had very forcefully hammered the valves. When we removed the cylinder head with the engine in the frame there were strong valve marks on the piston domes. The pistons weren't damaged but they were significantly marked.

With the cylinder head off we spun the crank feeling for any looseness or mechanical irregularities (hint, hint). While we didn't find anything that was really alarming, based on the damage I elected to buy an insurance policy against Bad Surprises and paid to have the engine pulled and inspected. There were no problems found but it did allow us to change all the stuck piston rings.

After my engine was put back together it had massive vibrations, this time Yamaha paid to have my engine pulled and inspected a second time. The problem was eventually tracked down to too many alignment marks on the balancer lobe and insufficient factory documentation leading to my front engine balancer being set 120° out of phase.

Given your situation, I'd first pull the head and then rotate the engine feeling for mechanical looseness or roughness. If the crank spins smoothly all you are looking at is a head job -- err, a cylinder head rebuild or replacement. I'm guessing a cylinder head rebuild with machine shop costs, all new parts and a Yamaha shop assembly will run $700 to $1.1k. I've got the parts and price list someplace.

Edit: With the cam chain removed from the crank and cams, and spark plugs out, you can do the crank test with the heads in place. The only thing that this test can't tell you is if the crank flexed and kissed the crank bearings. Mine did not bottom out on the crank bearings and it really got whacked. The rod bearings and wrist pins looked good too.

 

[Ramblin Man]

I hate to even ask this question. Assuming this is on your own dime and you decide to rebuild your head, you going with stock Yamaha parts or you going with aftermarket valves guides and seals?

Someone said a gen II head will bolt right on a gen 1 block? that real and for true?

 

[SkooterG]

Dead Gen I. Possible good price on late model, low mileage Gen II replacement.
Is that the "why" of which you asked?

Kinda.

Yours is dead? Have I missed some thread?

 

[RadioHowie]

Dead Gen I. Possible good price on late model, low mileage Gen II replacement.
Is that the "why" of which you asked?

Kinda.

Yours is dead? Have I missed some thread?

You've probably been out riding.

"Sigh" wish I could.

HERE

Another typical too long RH thread. At least stick with it through Post #33.

Great bedtime reading.

 

[Allnight]

...
You've probably been out riding.

"Sigh" wish I could.

HERE

Another typical too long RH thread. At least stick with it through Post #33.

Great bedtime reading.

Great bedtime reading??? You just kept me up for the last hour, and now I'm gonna have nightmares! Thanks a lot!

(And sorry for the troubles, but please keep them to yourself. Last time I had a pucker moment, I told another rider, and their next ride they did, and it kept going for 3 or 4 people.)