Honda GL1100 Water Pump Replacement

| 6/24/2013 4:58:00 PM

1975 Honda GL1000 

When the new-for-1975 Honda GL1000 was introduced, it was the world's first mass production water-cooled, shaft-driven flat-four motorcycle. Evolutionary and revolutionary, it employed proven practices in an entirely new package.

One of those practices was water cooling, up to then seen on only a few motorcycles, including the classic 2-stroke Scott and Suzuki's GT750 2-stroke triple. The Honda GL1000 was a hit, with some 100,000 sold in the U.S. during the model's 1975-1979 production run.

Honda followed the GL1000 with the 1980-1983 GL1100. Slightly larger and with more creature comforts, the GL1100 was mechanically very similar to the GL1000 and continued the GL's reputation for solid engineering and bulletproof reliability.

Sponsored by


Yet as reliable as those bikes were — and still are — the youngest Honda GL1100 is now pushing 34 years of age and the oldest GL1000 39. Time flies when you're on two wheels. And as these were bikes made for touring, a typical GL1000 or 1100 today can easily be approaching — or exceeding — 100,000 miles. These bikes amass high miles with ease, but like any bike they have critical points of maintenance that are often overlooked.

On the GL, one of those points is the water pump. An obvious sign that replacement is nigh is a slight coolant leak from the "weep" hole in the front engine cover, directly below the water pump. When the water pump's seals start to fail, coolant will pass into the front cover and out this hole.

4/22/2015 11:28:08 AM

Goldwing GL1100 engine knocks on take off and is quit thereafter.

8/20/2013 1:48:49 AM

I wrote the same procedure up on my web site: One important step you left out that is found on later 1100's that have the neutral switch mounted inside the front cover, is aligning the neutral switch with the shifter crank. Failing to do this before reinstalling the front cover will result in incorrect or no neutral light functionality.

Richard Sunnbobb
8/19/2013 5:38:17 AM

A very well written article about a gritty little job. Good work, and thanks.