Engine swap: any advice?

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Aasland

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I've been living with a non-functional 2nd gear (worn gear dogs) for about two years now, and I'm sick of it, and I got a deal on a used 2007 engine, so I'm going to swap the engines out (I have a 2006). I did consider splitting my existing engine and just fixing the transmission, but it has 98k on it so this way I get a fresher engine too. Also, new engine is complete with throttle bodies, but is missing a stator and the oil cooler is broken. I can salvage both of these off my 2006.

At the moment I'm doing lots of reading and I don't see anything technically beyond my limits, but I do have some questions, and I would like any advice that will make this easier.

  1. Swap in the updated CCT from my 2006.
  2. Add the stator from my 2006 if it doesn't look burned
  3. Swap oil coolers
  4. Once I have the exhaust off, I'll cut the cat's out, I hear it helps with the heat harbored down there. Any reason not to do this?
  5. Looks like I can drop the engine with the bike on the center stand (I will put a 1/2" board under it to get a little more clearance)
  6. I'll remove the front wheel for extra clearance and prop the axle up on a car jack.
What else - is there something else I should be doing while I'm in there, to make things easier?

 
I did an engine swap on an FZ1. One word of advice. If you're going to do it on the center stand leave the front wheel on and get a good wheel chock for added stability.

 
While the new engine is on the floor, do a cylinder leak down test before doing anything else. You really want to know that the new bullet is live. Passing that, do a valve check/adjustment and check the cam chain tensioner.

Why is the stator missing? If it was due to cover damage you need to check the rotor. While doing the valve check rotate the engine and verify the rotor turns true. Due to the awesomeness of the magnet you can't use anything magnetic anyplace near that bad boy and really, seriously watch out for pinched fingers 'cause it BITES.

Why is the oil cooler broken? Did the engine run without oil pressure?

When you are putting the new engine in, pay attention to the plastic bits that run around the front of the frame. If they do not stay in place any later work around the cooling system and horns will be real hard.

Do you have any reliable history about this engine?

 
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When you change the CCT, take the right cover off and tie wrap the cam chain. Don't chance a skipped tooth........ might as well do a valve check while you're at it and it's easy while on the bench..........

Take a look at the Reviving a Wounded FJR thread..........

 
I did an engine swap on an FZ1. One word of advice. If you're going to do it on the center stand leave the front wheel on and get a good wheel chock for added stability.
To keep the bike from moving forwards and coming off the centerstand?

 
Take a look at the recent thread by Streethawk. Although he split the cases for the repair, still lots of great information to reference..

--G

 
I did an engine swap on an FZ1. One word of advice. If you're going to do it on the center stand leave the front wheel on and get a good wheel chock for added stability.
To keep the bike from moving forwards and coming off the centerstand?
And side to side stability as well.
I was thinking getting the wheel off would be nice for access, but in looking at Streethawk's posts, that doesn't appear to be necessary (thanks escapefjrtis!)

 
While the new engine is on the floor, do a cylinder leak down test before doing anything else. You really want to know that the new bullet is live. Passing that, do a valve check/adjustment and check the cam chain tensioner.
Good idea. The donor has 26k miles on it, I will do the valves, plugs, tbs, leakdown, etc. before putting it into the bike.

Why is the stator missing? If it was due to cover damage you need to check the rotor. While doing the valve check rotate the engine and verify the rotor turns true. Due to the awesomeness of the magnet you can't use anything magnetic anyplace near that bad boy and really, seriously watch out for pinched fingers 'cause it BITES.
The cover is missing because the previous owner crashed and the forks bent into the right side of the engine and cracked the stator cover. Seller claims the stator is straight .. I will verify ...

Why is the oil cooler broken? Did the engine run without oil pressure?
The fork that broke the stator cover also pulled on a cooler line which pulled it out of the oil cooler. I'm hoping that the tip-over switch worked correctly ;-)

When you are putting the new engine in, pay attention to the plastic bits that run around the front of the frame. If they do not stay in place any later work around the cooling system and horns will be real hard.
Plastic bits. Got it.

Hey I noticed Streethawk pulled his entire upper fairing around the dash off - is that necessary?

Do you have any reliable history about this engine?
Only from the seller who bought it at auction. Like nearly any used engine, there will be some element of crapshootery involved. I'm hoping that all goes well and this engine will last for many more years. If not .. it has a 14 day warranty... and the price is low enough to justify it for the transmission parts alone, if I get motivated enough to crack two cases. Or simply taking it apart and selling it for parts (heads, stators, throttlebodies cases etc).

 
Why is the stator missing?...While doing the valve check rotate the engine and verify the rotor turns true...
...the forks bent into the right side of the engine and cracked the stator cover. Seller claims the stator is straight .. I will verify ...
Not just the stator, the rotor on the end of the engine crank should be checked.

When you are putting the new engine in, pay attention to the plastic bits that run around the front of the frame. If they do not stay in place any later work around the cooling system and horns will be real hard.
Plastic bits. Got it...Hey I noticed Streethawk pulled his entire upper fairing around the dash off - is that necessary?
It's not absolutely necessary, when you start accessing bolts 'n screws up around the steering head you will be able to answer this one for yourself.

Do you have any reliable history about this engine?
Only from the seller who bought it at auction. Like nearly any used engine, there will be some element of crapshootery involved. I'm hoping that all goes well and this engine will last for many more years. If not .. it has a 14 day warranty... and the price is low enough to justify it for the transmission parts alone, if I get motivated enough to crack two cases. Or simply taking it apart and selling it for parts (heads, stators, throttlebodies cases etc).
I once had that attitude. This rookie pulled out the engine bomb remnants from his frame and installed a warranty engine, transferred all the aux. pieces from the bomb onto the warranty engine to complete it only to find that the warranty engine had a leak down rate of 65% on two cylinders (>92% would have pleased me). Out of the frame comes the warranty engine, off come the bomb parts. Pallet the warranty, notify the seller (who was very good about it) and ship 'er back. Locate another engine with assurances that it is a Gen I and they already did a leak down test. I asked the seller for a copy of the salvage and insurance papers, through this I find out the engine was in fact an '07. Then I find out there is a crushed plate on the back of the engine, and then another crushed plate... It began to smell worse and worse. I wasted almost 8 weeks during this fiasco. Finally I saw the light and rebuilt the bomb. The bomb is now approaching 100k miles.

 
Let's say your current engine will go another 100K... are you happy with that? Pretty reliable I'd say, but since you have to pull it anyway, time to peek into the intakes to see if there's build-up on the intake valves, and other things you can look at while it's out on the floor. IF it were me, I'd be trying not to pull the cylinder head off as I just hate to disturb that unless forced to (just my mindset).

The tranny parts you'll need to fix second gear are relatively cheap..... probably $300-400 including gaskets and misc. The worst of the job is all the labour time.

Your choice of course, you have to weigh all the factors in your mind.

 
Let's say your current engine will go another 100K... are you happy with that?
Yes, and I have no doubt that it can do that. The oil analysis consistently comes back clean and the compression is high.

I've pulled heads and blocks on other engines (new rings, carbon removal etc) and yeah, that's not a route I want to go.

The tranny parts you'll need to fix second gear are relatively cheap..... probably $300-400 including gaskets and misc. The worst of the job is all the labour time. Your choice of course, you have to weigh all the factors in your mind.
Well ... I've seen the parts prices about double that, but more important to me is the time required to split the engine and perform the repair. I can probably get the new engine installed before the snow melts, but splitting the cases may take a whole Minnesota winter. That's a choice I don't have to make yet.

 
Going through the factory manual ... I see it lists the following for "Engine Removal" - are these necessary?

  • Throttle bodies
    - Do these need to come off to clear the frame?
  • Water pump
  • Starter motor
    - Isn't this nicely buried between the engine and the transmission?

And is this tool necessary:

  • Pivot Shaft Wrench
    - To loosen a "spacer bolt". Looks like a 14-15 mm nut to me ... or is there something underneath it?
 
I think the throlttle bodies can stay but I would remove them and clean while your at it.

No on the starter and water pump. I would remove the starter and clean it up inside and bench test it. If you don't want to send it to me and I'll do it and turn it around in a day.

 
Going through the factory manual ... I see it lists the following for "Engine Removal" - are these necessary?

  • Throttle bodies- Do these need to come off to clear the frame? Yes, you'll probably need to pull them to have access to the leads feeding the starter motor. Easy enough to remove.
  • Water pump Nope, that can stay
  • Starter motor Nope, it stays put.- Isn't this nicely buried between the engine and the transmission? Good thing few FJR owners have reported starter issues, eh?

And is this tool necessary:

  • Pivot Shaft Wrench- To loosen a "spacer bolt". Looks like a 14-15 mm nut to me ... or is there something underneath it? IIRC I accomplished this with a large flat blade screwdriver without issue. YMMV. I think it was a slotted spacer that I'm sure Yamaha has a spanner tool for.
Leave the front wheel on while dropping the motor; the frame is easy enough to manipulate around the motor with you and a buddy. You may find it easier to carefully lower the motor with a floor/motorcycle jack, then lift the front of the bike up over it. Remove the front fender though, or else the exhaust studs can scratch the paint while removing the engine. DAMHIK.

 
Ok. Got the new engine, all looks good. Stator is straight.

Now for the leak-down test.

What is an acceptable value on our engines?

I do have an issue with the leakdown test adapter I have (the OTC model) ... it has a hose that screws into an adapter which screws into the spark plug hole. The 10mm threaded adapter fits a 17mm 11/16 socket; it's pretty tight in that spark plug hole, I don't have any 17mm 11/16 sockets that fit in there.

I have a few options:

  1. Threadlock the adapter to the hose and hope it doesn't get stuck in the head
  2. Find a very thinwalled 17mm 11/16 socket
  3. Buy the $150 motion pro kit (has a 10mm thread on the hose)
  4. Make my own tool that fits in the sparkplug hole,
Thoughts ?

 
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I think the throlttle bodies can stay but I would remove them and clean while your at it.
No on the starter and water pump. I would remove the starter and clean it up inside and bench test it. If you don't want to send it to me and I'll do it and turn it around in a day.
I'm in a time crunch to get this engine started within the 14 day warranty period .. so I will just use the starter that's in there.

 
My compression gauge came with a selection of adapters including the 10mm thread that could be clipped to the leak down gauge. When I needed to do a compression test my 10mm adapter and only my 10mm adapter went MIA. After I no longer needed it, there it was, sitting right where it should have been. If your leak down tester will take clip on type adapters LMK and we can compare notes and see if my adapter will fit your tester, if it does we can work something out.

With a cold engine that may not have been run in a while, 85% should be minimally acceptable(1) anything over 92% is great and 94% to 96% is as good as any mass produced engine is likely to get.

(1) If the leak down is in the 85% area, listen through the crank case, like at the oil fill hole. If you hear air leaking here the rings are not seating, but this is probably OK and a little Ring Free over time and just running the engine should take care of this. If the air is leaking past the intake valves you will hear it in the throttle bodies, this isn't so good. If you hear it leaking past the exhaust valves it's not as big an issue as the intake valves. It could be carbon on the valve seats or the back of the valves. It would be worrisome if the exhaust valves were so far out of adjustment that they are starting to leak. You will likely hear air leaking everyplace, just try to assess how much each area is leaking. I use an audio amplifier to help listen, you may have one around your house but misnamed as 'tubing' or 'pipe' ;)

 
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Bah. One good cylinder, one mediocre (19%, through the rings and exhaust valve), and two with no compression (through the intake valves).

"GREAT COMPRESSION" my @ss.

However .. seeing that I have another bike with a good head on it .. I'm thinking .. why not swap heads? It looks trivial, much easier than paying a couple hundred to send the engine back and start over, or cracking open the transmission. It can't be much worse than when I rebuilt the KZ1100 head and put new pistons in it ... maybe $100 in gaskets and new bolts.

Thoughts?

EDIT: After a beer my brain started working better.

I did check the valve clearance; the leaky valves did have some clearance there so they weren't much worn, and not held open by the camshaft. The timing chain was OK, so it hadn't skipped teeth, presumably the valves aren't bent.

Why not pull the head, clean it up, put it back on with the old gasket and bolts, re-test the leakdown? If all is good ... pull it off, get a new gasket and bolts and button it up for good? Then I'll also get to look at the cylinders.

 
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