84 gl1200 Engine change.

Information and questions on GL1200 Goldwings (1984-1987)
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1984 GL1200I Interstate

84 gl1200 Engine change.

Post by starfleetengineer » Sat Mar 19, 2011 5:16 pm

Well, it's taken awhile to get this done. But for those who don't know, I suffered a stroke on Feb. 9. so this has taken me awhile to do. Let me recap the reasons for the change. When I bought the bike it ran good, but, it had a funny noise coming from the back of the engine. It sounded like marbals rolling around in a cardboard box or a decial engine. A few people listened to it and had no clue on what it was. at idle I had 12.75 volts charge and the noise. When the rpms' are rasied the voltage goes to 14.2+ and the noise goes away. I was told it could be a carb sync problem. I noticed that the tank had a little rust in the bottom so I decited to remove the carbs and clean them and clean the tank. When I removed the float bowls I found crud in their. I decited to replace the jets and the mixture screws too. After cleaning and replaceing things I put the carbs back in and set them. Now 2 problems. The noise is still there and now it runs like crap. Before I didn't even have to use the choke to start it. Now I have to use the choke and it sounds like it's running lean. But it uses gas like it has holes in the hose. On one test ride, I stoped at 7/11 to pick up a dew, and bam! She wouldn't start. The stater quit. Now I was thinking that the noise I hear is the stater coming apart. So I got an engine. It took me 4 days to get it done. I Had problems with the engine going back in the mounts. Went from an 84 engine to a 86. The starters sit diffrently on the case. Had to cut the plug off my old engine that comes from under the front right of the engine. The new engine had a female plug. It may have 6 wires in it compaired to the old one that has 3, but it works fine. Now with the engine in and warming up. I took the back of the other engine off. :o :shock: OMG you wouldn't beleive what I found. The magnetic hub for the stator was still on the stator when I pulled the cover off. The nut and washer were in the stator. The threads in the nut where mashed down. But the threads on the stator shaft are fine. Now I know what my noise was. Lucky it didn't explode :D Now that the engine is warm I set the idle drop, but it was weird, I had to have the screws out almost 4 1/2 turns. Now I sync the carbs. The vac was very eratic and low only about 10 - 15 inches. When I took it out for a test run it would pop in the air box, and had a lack of power, unless I put the choke on. Hum, same problem as on the other engine. Floats are set at 7.5mm. Thursday morning I decited to pull the carbs back out and recheck myself. Everything looked right and clean. Now I am a little tired because of the stroke, my stamina isn't what it was, so I took a break. I was sitting thinking what did I miss. Then I thought, I didn't have the fuel problem, till I changed the jets. Now mind you this is the second set of jets. The first ones where too big for the engine so they sent me the right jets for an 84 gl1200. I looked at the old jets, 112 and 125 and the mixture screws looked a little differant. So acting on a hunch I put all the old stuff back in. I put the carbs back in and ran her till hot again. I set the mix, or idle drop. Now the screws are set at 2 3/4 out. Big diff! I set the carb sync. I mad at the vac gages cause I tried useing diff damping valves and they leak. I finaly set it by ear, listening to the engine and then to the exh out the back. Yes I know this isn't the right way, but understand after my stroke, I have a shorter temper :cry:.
I let the engine cool back down, then started back up. No choke needed, and when I added choke it tried to kill the engine. I took it out on the road. She ran like a dream :D :D . No hessitation no poping, no back fire. She has more power now than before. I hear a very slight tick in the valve covers and on cold start up " after sitting over night" she has a slight knock for 1 to 2 sec's in the lower end. I have contacted the guy I got the engine from since it has a warrenty. I have learned alot with this expearance.

1. You don't have to change your jets, unless they are messed up.
2. Listen to what others have to say. what they have to offer is gold.
3. If you have an idea of what you think it might be, don't dismiss it. It's your bike and you know the sounds and how it runs.
4. Take the time to do it right. Short cuts are just like "Excuses" ;) We all know what that means :)
I will post the picks I took.

Engine Change
Engine Change

Magnetic hub on stater
Magnetic hub on stater

Nut and washer behind the stator
Nut and washer behind the stator

How many times do I have to tell ya,,, The right tool for the right job!

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Re: 84 gl1200 Engine change.

Post by Mooseman » Sat Mar 19, 2011 9:00 pm

Thanks for the update. Lots of good information....
Enjoy the ride. They are all good, just some better than others.

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Re: 84 gl1200 Engine change.

Post by WingAdmin » Sun Mar 20, 2011 7:27 pm

Excellent! Glad to hear the news! I know this has been a big and at times frustrating project for you! Now get out and ride! :)

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