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ContinuousWave: Whaler Performance
89' 150 Johnsons, just keep going and going!
|Author||Topic: 89' 150 Johnsons, just keep going and going!|
posted 12-21-2002 11:25 AM ET (US)
A few months ago, I posted several messages regarding low compression in 1 cylinder(60-75)on starboard motor. The port motor is in good shape. I spoke with several mechanics and friends who all had different opinions, rebuild, and repower, etc. One opinion in particular was the cylinder may have been that way for years, and I should just run it-gently.
So, I had the carbs cleaned on both motors, tune up, waterpumps, thermostats, and decided to seatrial before winterizing. The rpm's were up on both and TEMP was down, the boat ran great, cruised nicely at 3500rpms at 27mph. However at idle I noticed the temp did rise abit but, not in the red...If I can get a couple of years out of these I'll be happy...Just thought I would share this experience. The real test will be this summer, thats taking too long to get here...Any similar experiences?
posted 12-21-2002 05:38 PM ET (US)
Hommy I just repowered with a new 2002
150 johnson and have my old 150 evinrude
1990 runs great but needs a water pump
if you want it
I will let it go cheep. I might part it out
will let you know. gvisko
posted 12-22-2002 07:22 AM ET (US)
I run a '92 evinrude 225 on my Outrage 22, 6 cyl. loop-charged (your 150 is a 4-cyl, I think, but also loop-charged and generally technically similar to my motor).
Upon winterization this past fall (before de-carbonizing) I ran a compression check and found all my cylinders to be running between 80# and 90# which is significantly lower than the 100# to 120# I thought I should expect. Through the kind help of Clark Roberts here on the forum and his discussion with an OMC expert, I came to understand that my compression was OK, as a number of OMC loopers of that era left the factory with an intended compression in that range.
So your compression may not be all that bad, especially if your other cylinders are at least down close to the range of the one you reference. The bigger issue or concern would be if the one cylinder is significantly more than 10% lower than the average of the others. Even then I would undertake a strong de-carbonizing (or maybe two) in the event you just have a stuck ring or something similar before I'd be terribly concerned.
posted 12-22-2002 10:47 AM ET (US)
gvisko, Thanks for the offer, I will keep you in mind. Where are you located?
kingfish, These 150's are v6's and the compression on the remaining cylinders were around 90lbs. A mechanic used "power tune" on the low cylinder to try and bring it up but didn't work. On seatrial they both ran well, top speed was 42mph at or above 5500 rpms.(These engines are on a 25' Outrage cuddy/whalerdrive) The whalerdrive allows the boat to get on plane easily, 3000rpms at 20mph.(slow but comfortable)
Another mechanic told me his uncle ran his 200 hp Evinrude while 1 cylinder wasn't firing, this went on for entire season and he wasn't aware of it until he winterized the engine.
posted 12-22-2002 11:10 AM ET (US)
Thanks for the clarification - I knew that at one time, but I think my memory has been operating on the "full cup" theory for some time now. Every time something new gets added to the database, something old flows over the top and is gone...
So the benchmark would be if your low-reading cylinder was significantly more than 10% bekow the average of the other five rather than the other three.
How did your mechanic use power tune on just the one cylinder?
posted 12-22-2002 08:44 PM ET (US)
I'm not sure how he used the power tune. He thought it might increase the compression...This mechanic said, "the motor could last a day or a year, its unknown how long that cylinder/piston will last". A friend of mine using a special camera was able to look inside and see what appeared to be scoring on the cylinder wall. These motors have approx. 650 hours and haven't seen any real prevenitive maintence until I got them.(They've been sitting for the last 2 1/2 years) I changed all the fuel filters, lowergear oil, plugs, powerpack on port motor, waterpumps, etc. I'm hopeing I'll get a couple of seasons before I repower or go with a remanufactured powerhead... I'm really amazed at how that starboard motor ran. The boat is winterized now, and won't be back in the water until March.
|Tom W Clark||
posted 12-22-2002 08:53 PM ET (US)
Don't hold your breath waiting for that motor to die. It is a really robust design and can wthstand a lot of abuse. I had a 1990 Johnson 150 that ran, and ran well, for over an hour with no oil at all. Good luck trying to kill your 1989.
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