Gold Wing Engines - When to Separate the Engine Cases

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Rednaxs60

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This subject is well discussed in old and new threads alike on the various forums. The issue is generally because a person found an older Gold Wing that is a barn find, been sitting for a long time, and such, and the engine will not turn over. The prevalent mindset is to use a "magic potion" of whatever to try to free the rings from the cylinder walls.

This is necessary before any work can be started such as changing timing belts, starting the engine to determine how it operates, and such. A lot of the threads indicate that the engine is out of the frame when this process is being done.

The issues do not end with the engine being freed up. If the piston rings are stuck when you purchase/acquire the bike, the piston rings are probably going to be gummed up, or whatever in the piston ring grooves such that the rings will not "float" in the grooves and seal against the cylinder walls like these should. Oil leak by and smoke on start up are two indications the rings are not sealing as intended.

Once you get the engine rolling over, should you continue with the process, separate the case and look inside. Once you have the engine out of the frame, have the heads off to check the cylinders - this is done a lot engine in frame or out, the next step to separate the engine cases is not that difficult. You've already done the hard part.

Having the engine out, heads of and the rear case removed for clutch work and such is also another scenario. Now you have really got the engine stripped down. Add to this having the water pump cover off to check the water pump or to replace it. Now you are looking at some 70% of the work to get to separating the cases done.

I've read threads where a person will take the engine out to refurbish the heads, or to do the clutch, and ultimately asks the question what else should I look at, or renew. We all dance around the subject of separating the engine cases, and doing a ring job. Rings are an inexpensive item and a good machine shop can help source a set of rings and fit them. Canuckxxxx used the rings from an early model Chev Tracker in his 1100 rebuild, $22.00 CDN for the ring set, good price.

There are many considerations regarding separating the engine cases, or doing any work on the engine where you remove covers and such. You need the OEM service manual. You can do the job without this manual, but there are lots of detail(s) in the manual that are good to know, especially when joining the engine cases after the internal work/inspection(s) are done. You need the tools and work space to do this, and the confidence as well. These are not complicated engines, but do look and seem intimidating when you start down this road.

You don't have to replace any connecting rod or crank journal bearings. These seem to stand up to the rigours of time very well. You can hone the cylinders and use the same piston ring set again, not optimal, but has been done on many occasions. An engine gasket set is a must as well.

So why is it that the prevalent mindset is to not separate the engine cases and check the inside of the engine. Seems that it is alright to remove the rear engine cover, heads, and water pump cover to do work. Lots of recommendations on what to inspect and renew with the engine in or out of the frame, but when we get the that last huge hunk of aluminum called the engine case, we come to grinding/screeching halt.

There are lots of reasons not to separate the engine cases, some of the threads have mentioned that it's a bear of a job. I was fortunate when I separated my cases in that the cases separated rather easily. Kept hitting the case with a wood dowel, gingerly of course, until I saw a crack where the cases joined.

Timeline for open/inspect/close is solely dependent on what you find. I had two seized bearings that I had to replace. Did the con rod and crank journal bearings, new primary chain, new primary sprocket rubber dampers, new rings, hone the cylinders, a very good refresh all round. I did a lot of work internal to the engine, but I'm also keeping the bike for the long run.

Purchasing another used engine of the same vintage is just that, a used engine with an unknown history. A used engine is always less expensive, but it is a used engine with an unknown history. Taking your engine apart, inspecting the internals, maybe new rings and a cylinder hone, have a good look at the con rod and crank journal bearings, put back together and you know exactly what the heart of your bike is like.

My reason for starting this thread is not to be vilified as a heretic of the prevailing mindset, but to discuss why the response to the question of rebuilding an engine, or should work be done internal to the engine is more often if it ain't broke don't fix it, or cheaper to look for a used engine - no such thing as a good used engine, no telling what you are going to get.

I would not discourage anyone from separating a Gold Wing engine case to do work/inspect the internal part/pieces. It is; however, a major project that requires the person to define the project scope and such to ensure a good recipe for success. If it is too daunting, don't do it, if not too daunting go for it.

I know we live in a throw it away society, we don't fix what we have, we throw it out and get something else to do the job. I must mention that it is very gratifying to do the work, and have it turn out well after the fact.

Having mentioned the above, comments/opinions are appreciated. Don't shoot the author, maybe a keel hauling or such.

Cheers
 

mcgovern61

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I'll add this...when your engine starts to sound like it is a diesel engine rather than a gas engine, it might be a good time to split the case:

Listen to the tapping/knocking at 3-4K. Mind you, I am purposely throttling hard to make it tap and I am speed shifting since I am holding the camera in my left hand. This engine kept right on running:

https://www.youtube.com/watch?v=2SyhI7BDnhE


In this video, it is a cold startup and you can hear the bearings rattle initially until the oil pressure comes up. Surprisingly, no smoke and 150 compression on all 4!

https://www.youtube.com/watch?v=pksFHj4mLu8


Ok, one more for the noisy engine! Listen to the internals on this one:

https://www.youtube.com/watch?v=iS-71Bs_1Oc

 

mcgovern61

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So.....I split the case and found that there was Gold in them thar bearings! :smilie_happy:

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Piston skirts had a little bit of play as well as the wristpins and maybe even the connecting rod bearings..... :smilie_happy:

I didn't need plastigauge to check clearances, I was able to use a standard ruler. :smilie_happy: :mrgreen:

https://www.youtube.com/watch?v=XjnwxRwnU08
 

Rednaxs60

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Nice videos. My reason for rebuilding my 1200 engine was a planned one - keeping the bike so I wanted to bring it back to as close to when it left the factory. Was running well, but did have a couple of noises I could not identify. The only question was when. Last year afforded me the opportunity to move the rebuild schedule up. Had been buying new parts/pieces over time to lessen the pain of bulk buying for an older motorcycle.

I would submit that the time to look at the internal engine components is when you have to, or want to. When I was learning about mechanics, never was one, but the time I spent learning at my Father's garage has been invaluable over time. He mentioned on more than one occasion that if you rebuild the top end, heads, you should do the bottom end, keeps everything in balance. An engine is all about balance. Keeping everything as close as possible to the same condition pays off later on.
 

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