Engine switch

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philellis123

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My 2006 engine needs to be rebuilt or replaced according to my local shop. I found a 2004 engine on Ebay that is at an OK price. My question is, can I switch out the 2006 engine with the 2004?

 
The question is why? There will be some differences that may or may not be a major problem but why take a chance when used Gen II engines come up quite regularly. Not to mention the fact that the 2004 engine could turn out to be a "ticker" - not a high percentage but there are more than just a few.

What happened to the old engine? How many miles on it?

 
How much is that engine? If you're not doing the swap yourself, I'd have to believe you could find a running Gen I for about the same cost as an engine plus labor to swap - it's going to take some time.

 
RossKean,

My 2006 has 131,000 miles. Not really sure what happened, but after a wet compression test at the local shop I was informed that I have 3 cylinders running at 100psi, and one cylinder running at 70. I was told that ideally, they should all be over 200. Supposedly, the valves were all in spec., and I change the oil out regularly, so I really don't know what happened. I am missing my steed terribly, and was just considering options to get her fixed. I am not mechanically inclined, so any work will be done by a local shop.

Eflyguy,

The engine is local to me, and is listed at $550. The local shop said that an engine swap would take 6-8 hours, at $95/hour. If I was going to get another bike, I would just save up and get a newer Gen 2. Just considering some cheaper options that let me keep my current baby.

 
The 2004 engine is not a direct swap. There are differences in controls including neutral switch, gear indicator. ECU is different and I am not sure if the Gen II ECU could be used or not. Also differences in stator (lower output). Not sure what else.

Is your bike noticeably low on power? My '07 has a fair number more miles than yours and continues to run just fine (in my opinion). I have no idea what the compression is for each cylinder and I have no intention of trying to find out. If I knew that compression was below spec, I would probably start to imagine all sorts of issues!

If I was in the position of having to swap an engine in my bike, I would probably see if I could find a Gen II engine with fewer than 60,000 miles or so. The few extra hundreds of dollars could get quickly eaten up in labor time if the engines weren't 100% compatible. As it is, they are charging more than the cost for the engine just for labor.

Is this something you would care to attempt on your own with a Gen II engine?

 
FredW,

I originally towed the bike to the shop because it would not start, after trying for a week and half. Up until that point, the bike had been my daily driver, so it had not been sitting for any length of time. The battery and stator are new.

RossKean,

You have officially talked me out of considering the swap with the 2004 engine, thank you for educating me on the differences between the years. I think I will continue to save my money and either get a newer engine or a newer bike.

 
The reason that I asked is because the readings are atypical of any normal type of failure. Normally when you have compression failure it is in one or two cylinders, not all 4, in an in-line 4 engine. Before I invested the amount of money it will require for an engine swap, Id think about getting a second opinion. You wouldnt go in for open heart surgery because you general practitioner hear a murmur would you?

Unless... you know you had a cam chain slip and heard the valve damage happen. Thats a whole different bag of worms, and could affect all cylinders.

 
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Adding to what Fred said - other than a catastrophic event such as a cam chain slip (due to CCT problem or incompetent service), compression loss doesn't happen overnight. It also doesn't render an engine instantly useless after working fine the previous day. Possibility of flooding which makes starting difficult (try WOT). Could lower compression by washing oil off cylinder walls.

 
If the engine is still running and you are happy with it I say ride it untll you want to sell it, or sell it now, it or get a second opinion. You might consider a engine leak down test as compression test are not conclusive and prone to unreliable results. In the link it says, "Compression testing is a crude form of leak-down testing...."

 
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RossKean,

Well, I'll be damned. At your suggestion, I went out and tried to start my bike at WOT, and after 3 tries she STARTED! Son-of-a-bitch, she has been sitting for 2 months now, and maybe, just maybe, there was nothing wrong to begin with :( My bike is in a detached garage and it is currently 20 degrees outside, so I let her run for 5 minutes then shut her down. I sure hope she starts tomorrow, that would make me one happy camper. I will also be changing local shops to do maintenance and diagnostic work for me. THANK YOU for the suggestion!

 
RossKean,Well, I'll be damned. At your suggestion, I went out and tried to start my bike at WOT, and after 3 tries she STARTED! S
RossKean for the slow clap. He wins the Internet this month!

Philellis, I'd encourage you to visit a dedicated thread about was he was talking about here. I call it Fast Starter Syndrome. 5 minutes should be good as it warmed it up.

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Adding to what Fred said - other than a catastrophic event such as a cam chain slip (due to CCT problem or incompetent service), compression loss doesn't happen overnight. It also doesn't render an engine instantly useless after working fine the previous day. Possibility of flooding which makes starting difficult (try WOT). Could lower compression by washing oil off cylinder walls.
A compression test on a flooded engine will give false readings. A true reading is at operating Temp.

 
Yeah, it all became clear once it was known the change was sudden. First post was asking entirely the wrong question! Could have asked, "Why did the bike run fine one day then fail to start, and now shows very low compression?"

Not directing this at the OP, really, just saying it so maybe in the future, items like this (too late for you, philellis123) will start with what happened, rather than what some unknown party thinks the user needs.

 
Jeebus! I'm late to this one, but as soon as I read posts 7 and 9, I thought, FSS. The fuel taking the oil off the walls would help account for the low compression test. Effing bikes barely have any compression when that happens. That's why the starter spins them so fast.

Man, I'm glad you asked. It would SUCK to dump a perfectly good engine for something unknown, especially with the money involved!

 
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Phil, it would be a fine public service to inform your repair-shop or dealer of this.

 

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