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Re: GL1100 - HELP !!!

Posted: Sun Aug 11, 2019 1:41 am
by maury
I've been reading and looking today. I've purchased used heads before and rebuilt them - no problem.
I have never purchased a used piston and I'm wondering how they generally work out.
I haven't seen where new pistons can be purchased.

First thing is pulling it apart and looking things over before any purchases. Just wanted to get some opinions from the wise wrench turners out there.

Re: GL1100 - HELP !!!

Posted: Sun Aug 11, 2019 8:06 am
by robin1731
maury wrote:snip...…….
Like I say, running it on the starter now, it sounds very tight.
Doing that is just spreading the debris around inside the engine. Not a good idea.

.

Re: GL1100 - HELP !!!

Posted: Sun Aug 11, 2019 10:35 am
by maury
Thanks
Yeah for sure.
I only did that a short few seconds after things went bad.
Since getting the head off, only hand turn to see the movement and check the walls of the cylinders.
All is very smooth both in rotation and appearance.

Re: GL1100 - HELP !!!

Posted: Sun Aug 11, 2019 2:09 pm
by maury
Anyone able to guide / suggest things about purchasing pistons?

Re: GL1100 - HELP !!!

Posted: Sun Aug 11, 2019 4:15 pm
by robin1731
Probably easier to get piston/rod combo. You need to get the wrist pins pushed out of the piston to change them. It takes heat and a press to do it. Any engine machine shop could do it.

If you can get a combo where the rods have the same code as the ones in your engine now you can just use that piston/rod set. But you will need check piston to cylinder wall clearance no matter what you do.

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Re: GL1100 - HELP !!!

Posted: Mon Aug 12, 2019 4:43 pm
by maury
I don't know what the codes on the pistons actually mean.
The set in the engine currently - 468 S18
I'm finding - 468 S20, 468 S21, etc but none with "18" on the end.
Will any of these work?

Thanks

Re: GL1100 - HELP !!!

Posted: Mon Aug 12, 2019 9:52 pm
by robin1731
Not the pistons. There is a mark/code on each rod, the crank, and the engine cases. Those all need to be checked to see which bearing you need. In your case you need the mark from the rod and the corresponding throw on the crank. This is all explained in better detail in the service manual.

Since bearings are hard to find the best case for you would be to take the engine apart. Then see which mark the rods have which need replace. Then try to find rods with those same marks. That way if your bearings are still good you can just reuse the ones you have.

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Re: GL1100 - HELP !!!

Posted: Mon Aug 12, 2019 10:09 pm
by maury
I have the engine apart.
I misspoke/typed, the numbers I stated are on all the rods to the pistons.
The numbers on my rods and those on ebay are very close (only difference is the last 2 digits of the 6)
I'm new to this rod/piston thing and don't want to buy something incorrect.
I'm going to get the manual to read up on this.
Thanks so much

Re: GL1100 - HELP !!!

Posted: Mon Aug 12, 2019 10:49 pm
by maury
Ok,
In your reply you stated, "Then see which mark the rods have which need replace."
What mark are you speaking of?
In the manual it states to use a rod with the same weight code (that's all I see).
These are a 1 or 2 or 3.
My question now is this -
If I replace both the piston and rod with a used one. Does it matter what the weight code is?

Re: GL1100 - HELP !!!

Posted: Mon Aug 12, 2019 11:00 pm
by Explorer
In the Partzilla fiche it shows letter codes for con-rods and and color codes for big-end shells.

https://www.partzilla.com/catalog/honda ... ate/piston

Re: GL1100 - HELP !!!

Posted: Tue Aug 13, 2019 5:41 am
by Old Fogey
These pics are from a GL1000 but I believe the GL1100 will be the same.
crank 1.jpg
crank 1.jpg (142.29 KiB) Viewed 243 times
Crank 2.jpg
Crank 2.jpg (146.59 KiB) Viewed 243 times
Personally, in your neck of the woods where there is a reasonable supply of spare engines, that is the route I would go. I have an engine here where a piston really chewed on a valve, bending the rod. The crank has now a runout well beyond service limit.

Re: GL1100 - HELP !!!

Posted: Tue Aug 13, 2019 10:52 pm
by maury
Thanks very much !
But from the holy book itself (Honda shop manual).
Page 8-12
"When replacing a connecting rod, be sure to use a new rod having the same weight code"
Picture shows the side of a rod (just like your picture above) with arrow pointing to the number - states - "Codes may be 1, 2 or 3"

Then,
Page 8-16
"Record each connecting rod I.D. code number. Codes may be 1, 2 or 3."
Picture IS THE SAME EXACT AS I DESCRIBED FROM PAGE 8 - 12.

So........
It's a weight.......no it's an I.D. number !!

Could very well be a typo - I know they exist in a lot of tech publications.

I don't see where the weight of the piston itself matters. So I'm going to buy a couple used pistons and have them swapped to these rods that were on the engine originally.

Thanks everyone !!

Re: GL1100 - HELP !!!

Posted: Wed Aug 14, 2019 10:20 am
by Old Fogey
If it was a 1000 I'd be saying change the rods as well, but the 1100 rods are more substantial so you should be ok (I hope).

Re: GL1100 - HELP !!!

Posted: Wed Aug 14, 2019 11:59 am
by Sidecar Bob
maury wrote:Thanks very much !
But from the holy book itself (Honda shop manual).
Page 8-12
"When replacing a connecting rod, be sure to use a new rod having the same weight code"
Picture shows the side of a rod (just like your picture above) with arrow pointing to the number - states - "Codes may be 1, 2 or 3"

Then,
Page 8-16
"Record each connecting rod I.D. code number. Codes may be 1, 2 or 3."
Picture IS THE SAME EXACT AS I DESCRIBED FROM PAGE 8 - 12.

So........
It's a weight.......no it's an I.D. number !!

Could very well be a typo - I know they exist in a lot of tech publications.

I don't see where the weight of the piston itself matters. So I'm going to buy a couple used pistons and have them swapped to these rods that were on the engine originally.

Thanks everyone !!
I found the same thing a couple of years ago when I had to deal with a bent rod
https://www.ngwclub.com/forum/viewtopic.php?f=1&t=63395