Combining a 77 and 78 engine to make one.

Discuss everything about Honda GoldWing. Feel free to ask any question related to GoldWing.

Moderators: CYBORG, Oldewing, robin1731, Forum Moderators

Post Reply
elslimdiablo
Chrome Member
Chrome Member
Posts: 195
Joined: Sun Feb 21, 2016 7:36 pm
Location: Delaware

Combining a 77 and 78 engine to make one.

#1

Post by elslimdiablo »

I have a 77 gl1000 engine that had a broken ring score up the cylinder wall. I also have a 78 engine that appears good. (I have not opened it up yet to check it out though)
I know to use the cams, upper valve train and carbs from the 77, but is there anything else I need to swap over? Thanks- Slim
1977 GL1000, 1200 transplant, sold
1976 GL1000
1975 CB360T(in the family since new and restored)
1975 GL1000
1974 CB360
1961 T20 Tiger cub SL
1959 T20 Tiger cub S
03 Shadow Spirit 750
User avatar
ritalz
Honored Life Member
Honored Life Member
Posts: 4090
Joined: Sat Jun 25, 2005 10:22 am
Location: St Louis, MO

Re: Combining a 77 and 78 engine to make one.

#2

Post by ritalz »

The rear engine cover if you want to retain the kick starter.
Al

2003 Goldwing Daily Rider
1975 Goldwing 'Max'
1984 Goldwing New Bagger Project
1976 Goldwing 'Grocery Getter' Sold
1985 Goldwing Interstate 'NCC-1985' sold
1981 Silverwing Sold
1982 Goldeing Project Sold
1981 Goldwing Parted Out
1983 Goldwing Project Sold
1973 CB500F Long Gone
1966 CL77 First Street Bike
http://www.ngwclub.com/gallery3/index.p ... ans/ritalz
elslimdiablo
Chrome Member
Chrome Member
Posts: 195
Joined: Sun Feb 21, 2016 7:36 pm
Location: Delaware

Re: Combining a 77 and 78 engine to make one.

#3

Post by elslimdiablo »

Yea, that's already on the list. Are the timing marks on the cranks the same?
1977 GL1000, 1200 transplant, sold
1976 GL1000
1975 CB360T(in the family since new and restored)
1975 GL1000
1974 CB360
1961 T20 Tiger cub SL
1959 T20 Tiger cub S
03 Shadow Spirit 750
User avatar
wingrider
SUPER BIKER!!!!
SUPER BIKER!!!!
Posts: 3724
Joined: Thu May 24, 2012 12:15 pm
Location: Maple Lake, MN USA

Re: Combining a 77 and 78 engine to make one.

#4

Post by wingrider »

The timing marks will be slightly different between the two years.
2002 1800 Wing
2001 Valkyrie Interstate
1978 1200 EFI Wing with Motorvation Coupe Royale sidecar
1977 1200 Wing cafe/bobber project
1974 Suzuki GT550
User avatar
ericheath
Honored Life Member
Honored Life Member
Posts: 9580
Joined: Wed Jul 29, 2009 11:20 am
Location: Winnipeg, Manituba

Re: Combining a 77 and 78 engine to make one.

#5

Post by ericheath »

Ignition timing marks have five degrees difference. 75-77 is 5 BTDC and 78-79 is 10 BTDC.

Mechanical advancers are different, keep the one with the 77. (371)
Whatever I suggest here should be given ample time for a moderator to delicately correct. I apologize in advance.
77 WING, 1200 engine with 77 heads, cams, gl1100 foot pegs, Magna V65 front end, 764A carbs, [-gone Suzuki M109 monoshock--, replaced with gl1100 shocks] gl 1200 swing arm, gl1500 final drive, wheel and rear brakes Valkyrie seat, Meanstreak tank, Sportster pipes, Power Arc ignition off crank.
77 Wing. black
83 Wing, in pieces
"Continuing education is important even if the subject matter is fairly useless (as in this case)."---Greg Foresi
elslimdiablo
Chrome Member
Chrome Member
Posts: 195
Joined: Sun Feb 21, 2016 7:36 pm
Location: Delaware

Re: Combining a 77 and 78 engine to make one.

#6

Post by elslimdiablo »

I think I'll swap the crank assemblies to keep things where they should be.
1977 GL1000, 1200 transplant, sold
1976 GL1000
1975 CB360T(in the family since new and restored)
1975 GL1000
1974 CB360
1961 T20 Tiger cub SL
1959 T20 Tiger cub S
03 Shadow Spirit 750
User avatar
ericheath
Honored Life Member
Honored Life Member
Posts: 9580
Joined: Wed Jul 29, 2009 11:20 am
Location: Winnipeg, Manituba

Re: Combining a 77 and 78 engine to make one.

#7

Post by ericheath »

That makes it a pretty big job. If you want the five degree mark, just cut the distance between T and F in half. Others here have used a chisel to score a line in the crank.
Whatever I suggest here should be given ample time for a moderator to delicately correct. I apologize in advance.
77 WING, 1200 engine with 77 heads, cams, gl1100 foot pegs, Magna V65 front end, 764A carbs, [-gone Suzuki M109 monoshock--, replaced with gl1100 shocks] gl 1200 swing arm, gl1500 final drive, wheel and rear brakes Valkyrie seat, Meanstreak tank, Sportster pipes, Power Arc ignition off crank.
77 Wing. black
83 Wing, in pieces
"Continuing education is important even if the subject matter is fairly useless (as in this case)."---Greg Foresi
User avatar
pierce
Run Executive
Run Executive
Posts: 1288
Joined: Sat Dec 03, 2011 3:07 pm
My Album: pierce
Location: Madison

Re: Combining a 77 and 78 engine to make one.

#8

Post by pierce »

I think using the earlier crank and pistons, the whole shebang is a good idea. The end of the 77 crankshaft has the addition of the Kickstart mechanism. Not just the rest case.

I would also switch out the tensioner to the 1200 to reduce chain rattle.

If you are fairly mechanical, and time to yourself shouldn't take more than a day with prep.

Complete gasket set, ebay 120 maybe. Order used tensioner off eBay, a few dollars. Oil, oil filter, plugs and new coolant , belts and permatex gray to seal the case. Good to go for around 200.

See you in a few hundred thousand mies.
1976 GL1000
1978 Gl1000
elslimdiablo
Chrome Member
Chrome Member
Posts: 195
Joined: Sun Feb 21, 2016 7:36 pm
Location: Delaware

Re: Combining a 77 and 78 engine to make one.

#9

Post by elslimdiablo »

I already have the 1200 tensioner and will be taking some of the winter to get the job done. Im also thinking of getting the valves and valve guides done in the 77 heads for piece of mind. Thanks guys!
1977 GL1000, 1200 transplant, sold
1976 GL1000
1975 CB360T(in the family since new and restored)
1975 GL1000
1974 CB360
1961 T20 Tiger cub SL
1959 T20 Tiger cub S
03 Shadow Spirit 750
User avatar
delling3
Gold Member
Gold Member
Posts: 1177
Joined: Mon Sep 17, 2012 8:14 am
Location: Sterling Heights, Michigan

Re: Combining a 77 and 78 engine to make one.

#10

Post by delling3 »

Not wanting to hi-jack this thread, but I have a question reflecting my ignorance here. If the idea is to swap the crankshaft from engine 1 to engine 2, do you use the bearing shells from the donor engine, or the destination engine? Does it matter? I know that there are different bearing sizes. Is the size based only on the crank, or just the crankcase, or both?
delling3

1979 Yamaha XS750SF

Previous:
1978 GL1000 - JUNE 2017 BOTM: Sold
2006 Kawasaki Concours: Sold
1995 Kawasaki Concours: Crashed/totalled.
1976 GL1000: LAST RESTORATION, sold
1981 Honda CB900F Supersport: 3rd restoration, sold.
1979 Yamaha XS-750F: 2nd restoration, sold.
1982 Honda FT-500 Ascot: First (only) new bike. Family forces sale.
1973 CB500 Four: First restoration, long gone.
1972 Suzuki TS-100: First bike, sold.

Only dead fish go with the flow . . .
User avatar
CYBORG
Moderator
Moderator
Posts: 24536
Joined: Mon Jan 14, 2008 12:52 pm
Location: Muskegon mich

Re: Combining a 77 and 78 engine to make one.

#11

Post by CYBORG »

The "size" is in every engine. Back in the day called blueprinting. Both crank and rod bearings are Matched to the block and the crank. By color of the bearings. The difference in size from color to color is very small,......but different. The marks on the block are the factory determined colors for each block/crank combination.
Just changing a crank and block combination from one engine to another might work, as the differences between colors is very small, but defeats the original intent of the factory, and could limit the life of the engine
1978 custom GL1000
1977 custom with 1200 engine
1985 gl1200
User avatar
CYBORG
Moderator
Moderator
Posts: 24536
Joined: Mon Jan 14, 2008 12:52 pm
Location: Muskegon mich

Re: Combining a 77 and 78 engine to make one.

#12

Post by CYBORG »

If bearings were readily available in all colors, a factory fresh engine could be built. But in my experience, they are not. If you can find a source for all different color bearings, let me know. I have been looking for a long time
1978 custom GL1000
1977 custom with 1200 engine
1985 gl1200
User avatar
robin1731
Membership Admin
Membership Admin
Posts: 21724
Joined: Mon May 29, 2006 8:31 am
Location: Decatur, Indiana

Re: Combining a 77 and 78 engine to make one.

#13

Post by robin1731 »

A whole lot easier to just mark the crank you have.

Even if it all took the same bearings it would be a lot easier to mark the crank. Swapping it all out is a lot of work just to have the timing marks in the correct location.

.
1976 Goldwing Super Sport
1985 Honda Elite
1976 KZ900 Dragbike
1992 ZX7 Dragbike (KZ900 style motor w/NOS)
and a rotation of various purchases
Randakk approved Carb Rebuilder
elslimdiablo
Chrome Member
Chrome Member
Posts: 195
Joined: Sun Feb 21, 2016 7:36 pm
Location: Delaware

Re: Combining a 77 and 78 engine to make one.

#14

Post by elslimdiablo »

I measure out engines when I pull them apart for rebuild to see what it will need. I will use plastigauge to check the crank bearing clearance and go from there. I would like to retain the kickstarter if possible, but if things don't measure up in the swap, then I'll just have to do without. ( not a deal breaker, just love the idea of a kicker)
1977 GL1000, 1200 transplant, sold
1976 GL1000
1975 CB360T(in the family since new and restored)
1975 GL1000
1974 CB360
1961 T20 Tiger cub SL
1959 T20 Tiger cub S
03 Shadow Spirit 750
User avatar
delling3
Gold Member
Gold Member
Posts: 1177
Joined: Mon Sep 17, 2012 8:14 am
Location: Sterling Heights, Michigan

Re: Combining a 77 and 78 engine to make one.

#15

Post by delling3 »

From my first reply, I know that engine bearings are basically unobtainium. Once you pull a motor apart and start into plasticgauge, the assumption is that you can get bearings. Not so (at least for now) with 4-cylinder wings. I would lean towards using the bottom end of your donor engine as-is. Unless you have already confirmed that it needs a full rebuild. Then I might start looking for another donor. That's me, YMMV. I had a '76 with a kicker, and now have a '78 w/o. I would prefer to have it (for emergency use), but on the 'Wing they ain't very user friendly, and I don't think I would tear down a motor just to have a kickstarter. I would simply swap the top end/valve train, and mark the flywheel. Robin and Cyborg are far more experienced than I, and unless I mis-read their replies, I think they agree. In any case, good luck with your project!
delling3

1979 Yamaha XS750SF

Previous:
1978 GL1000 - JUNE 2017 BOTM: Sold
2006 Kawasaki Concours: Sold
1995 Kawasaki Concours: Crashed/totalled.
1976 GL1000: LAST RESTORATION, sold
1981 Honda CB900F Supersport: 3rd restoration, sold.
1979 Yamaha XS-750F: 2nd restoration, sold.
1982 Honda FT-500 Ascot: First (only) new bike. Family forces sale.
1973 CB500 Four: First restoration, long gone.
1972 Suzuki TS-100: First bike, sold.

Only dead fish go with the flow . . .
Post Reply

Return to “GoldWing Tech Discussions”