i recently purchased a 1978 17' silverline Nantucket with a 1977 johnson 140HP. The model number in the mounting bracket is missing but i think the model number would be: 140ML77 or 140TL77. I am going to get the shop manuals once i find them locally (can't bear to spend $70US just on shipping). But in the mean time i would really like to take it for a spin.
but i am a preventative maintenance guy. so after i started her up on the muffs i notice there was no "pisser". i noticed there were two holes water came out at the top of the gearcase pointing down (that looks like it would be submerged).
How do i know that water is circulating? (noticed a small pool on the right side by gear case shifter, will have to track that leak down later).
I should mention i have an old johnson 1973-1989 4-235HP shop manual i've been using. has a lot of good info but not as specific to the engine i have.
This is my first big v4 until now it's been 9hp.
i could take some pics and upload them if need be.
thanks and great forum!
Last edited by cdn-pk; May 25th, 2009 at 08:50 PM.
Reason: added some info for clarification
The factory did not put telltales on these engines till 1978, when they redesigned the outer exhaust cover with the hole. An easy solution is to find a 1978 or later outer exhaust cover and swap it for the one on your engine. Hold your palm just behind the exhaust relief ports in the midsection. After 45 seconds or so on a cold engine, the thermostat will open and water droplets will form on your palm. You know that the stats work, but still do not have a good idea about the impeller. I'd ask around and see if anyone has a laser temp gun you can borrow while you test run it on the hose. You are looking for 140-150 on each head at idle.