Hydro lock, low compression

Information and questions on GL1100 Goldwings (1980-1983)
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Joined: Sun Oct 04, 2015 3:36 pm
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Motorcycle: 1982 Gl1100

Hydro lock, low compression

Post by knockdolian »

Hi all, hope everyone is staying safe. Well 1982 1100. Pressed the start button yesterday to get a large clunk then nothing. Pulled the plugs and turned it over to get a huge squirt of fuel from No2 cylinder. I’ve taken the carbs off to give them a clean. Plenty of orange brown sand in the Bowles. I have a new inline filter and the needle seats have filters too. Put new seats and valves in about two years ago. While the carbs are off thought I’d do a compression test. I know I should probably have done it sooner but didn’t have my tester at the time
So cold test
1, 145
2, 125
3, 145
4, 135
Now I do know that the low reading could be down to a couple of things and do plan to check everything. Is there any way of checking for a bent con rod without striping. What reduction would I expect if I have bent it or will a 1100 wing starter motor not bend a rod ? Thanks in advance

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Re: Hydro lock, low compression

Post by DenverWinger »

I wouldn't worry about it. Bent con-rod from hydrolock in a 4cyl wing is extremely rare.
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Re: Hydro lock, low compression

Post by Rambozo »

More likely is that the difference in compression is from the fuel washing off any oil film between the pistons and cylinders.
Also be sure to change your oil before starting it up as I'm sure some fuel leaked past the rings into the crankcase.
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Re: Hydro lock, low compression

Post by Solo So Long »

Pull the plugs. By hand, turn the engine over and check the depth of each piston at bottom and top. They should all be the same. If you bent a rod (highly unlikely), that piston will be lower at bottom and top.

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