Mercury 150 compression test. . Repeat this process for each cylinder. Jun 29, 2012 · - Water supplied to the engine while cranking! Insert compression tester into #1 spark plug opening, and crank the engine until the reading no longer rises. My question is, Is that a normal reading for this motor or is it to low? What would be the next thing to check out to get the psi higher? Thanks May 11, 2025 · To properly test compression, warm up the engine, disable the ignition, and remove all spark plugs. Subscribed 46 1. 120 psi in all cylinders. Apr 5, 2025 · This guide provides a detailed, step-by-step process for performing a compression test on an outboard engine, along with expert insights, practical considerations, and troubleshooting tips to help boat owners maintain their engines effectively. Pressure test was performed with hot and cold engine using two different tester kits. Compression check was good on the port side but the starboard side it bad. If all 6 are within a 10% span the engine is probably healthy mechanically. We've explored the critical process of performing a compression test, from understanding its importance in assessing engine sealing to gathering the right tools and executing the test itself. Read about the causes of poor compression. 3K views 1 year ago Mercury 150 compression test and boroscopemore Oct 14, 2023 · I did a compression test on my 85 Merc BM 150 V6. To perform a compression test, remove the spark plugs and keep the kill lanyard off to prevent any spark. Next, screw in the compression gauge and crank the engine until the needle on the gauge stops moving, which typically takes about 5 revolutions. It's old and not the prettiest but it's decent. 2002 Mercury Outboard 150 hp Salt water series 2 stroke engine. What to look out for is one or two cylinders that compress more than 10% below the rest. it's a 75 Mercury 150hp. After the compression check, looked under the water jacket then had to remove the head. i know the general process but do i need to remove all the spark plugs wire while i do this or one at a time? Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. Post your results here. All the cylinders are 70 psi. We would like to show you a description here but the site won’t allow us. Good luck. Welcome to iboats. Apparently last owner just had compression test done. Mar 26, 2008 · i am going to do a compression test on my outboard. Record reading. One from Harbor freight and the other from Pep Jul 27, 2003 · Re: engine compression mercury 150 v6 efi My 97 efi 150 tested at 100 on all cylinders and the mechanic didn't seem worried about it. Go to the Engine FAQs forum ^^^ and do the compression test by the instructions there. Repeat above step for each cylinder. DO NOT spin/crank for longer than 10 seconds at a time. The motor is a 91 or 92 mercury 100 2 stroke. Aug 14, 2012 · 1997 Mercury 150 compression test Compression check was good on the port side but the starboard side it bad. Install the gauge in one cylinder at a time, crank the engine several times, and record the peak PSI. I don't know alot about boats but just tossing this on to see if there is any interest. Step by Step Instructions on how to correctly do an Outboard Compression Test on any outboard engine. Compression Test on a Mercury Salt Water series 2 stroke on a 2002 Pro-Line make / manufacturer:Mercury model name / number:150 HP delivery available more ads by this seller QR Code Link to This Post I pay cash for outboard engines Multiple horsepower’s for sale Trades welcome Integrity Outboards is a licensed marine dealer with the Texas Parks and Wildlife Department Push button electric tilt trim We can ship We Jan 17, 2012 · Re: 2002 Mercury 150Hp xr6 Compression and overall reliability of outboard Hey, Jim. The Impeller and lower gear oil was just done also. SHould I be worried? Jan 17, 2012 · Re: 2002 Mercury 150Hp xr6 Compression and overall reliability of outboard Hey, Jim. oebxjcj mmendo mheto aetpe enev djy peargr pez ljne osis