Overheatin question on 1979 140 Evinrude Crossflow

[emoney]

Ok, so today was "shakedown cruise day" (it was on the U.S. calender if you didn't see it) and we took the "new to me" boat out. On the way out, after idle speed of about
3/4 of mile (long channel), went WOT, all was well. Had the motor trimmed way too
high and started really porpoising (took me forever to remember that 'down' eliminates porpoising....duh) and all of a sudden it shut off. Hmmm? So, like any good red blooded novice boater, I restarted it and again, WOT, of course with more porpoising. She shut down again. This time I noticed the "key is in the ignition" warning buzzer. Hmm, I didn't know boats came with those. But, I decided to let it sit for a spell. Long story short, after I got my head out of "you-know-what" it dawned on me that the buzzer was the overheat buzzer. We floated for about an hour, turned the key to the first click and there was no buzzer and decided to head back in. On the way back, I finally remembered to trim down, dropped the RPMs to 4000 and she cruised all the way back,
into the channel and up to the ramp with no issue.

So, what do I look for first? There's a steady stream of water coming out the "pee hole"
and the cover didn't feel warm to the touch. This motor was recently worked on, in the carbs, fuel pump, fuel system arena as well as new plugs, timing check etc. There wasn't a new water pump installed, however. Can the water pump be going bad but still have a steady stream of water coming out? Did I bring on part of the issue with the severe porpoising and the WOT? Help a brother out, will you? Oh, and thanks!

 

[boobie]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

If it was my boat I'd take it back out again and run it with the t/t set at the correct angle and see what it does. You could have been picked up some aerated water when it was porpoising. Do this before you get to deep into it.

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

You know, I thought the same thing because it was smooth as a kitten coming in. I've also thought of something else; it could be a thermostat sticking issue, couldn't it? I say that because when I put it on the muffs to flush it out (about 3 hours after we used it), it started, ran, idled like a dream and again, steady stream of water out the "pee-er". Also, and this is something I could be imagining, but it seems like last night when I had it on the muffs, the water coming out of the tell tale was warm and just now is was nice and cool. Which one is correct? Because, if it's supposed to be cool, then I would think that would point me to a malfunctioning thermostat on the way out that freed it self on the ride. Does this even make sense or am I thinking wrong?

Also, and forgive my redundancy, but the porpoising, could it cause the engine to run hot because the motor, is in essence, coming up out of the water on every up roll? I'm ready to replace the water pump, impeller or the thermostat if folks think I should. I'm all about NOT breaking down (ain't we all)

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Ok, I've thought of another related question if I may. What would cause a "lot" of water to come out the exhaust relief ports? Unless my memory is really failing, it seems as if it was doing that last night on my motor, but not tonight during the flush out. Last night's "muff test" was only 1-2 minutes as I just wanted to make sure the batteries were up and that she'd turn over. Which she did immediately,
I'm proud to say. Now, if I just get her to cool down.........

 

[emdsapmgr]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

A strong telltale indicates that the water pump is getting fresh water to the powerhead. It does not mean that it won't overheat. You need to have water circulate through the powerhead in order to keep it cool. The cooling water goes through the block, then into the thermostat housing, then out the block. If you have stuck thermostats, water won't be able to exit the block. One/both sides of the block will overheat. Internal water passage blockages can restrict water flow in the block also. If the rubber water diverters by the cylinders deteriorate or get out of position, you can get an overheat. I'd borrow a laser temp gun, or rent one from an auto parts store. Run the engine and check the head temps. When idling, the heads should be between 143 and 155. When planing, the powerhead temps may go down from these temps. It's normal for water to exit the exhaust relief holes in the upper midsection-esp when on plane.

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Ok, I'll try to do that today and then check this afternoon. Can someone remind me the process of testing a thermostat? I remember it has something to do with boiling water. Also, are the t-stats tough to get at on these motors? And, are we saying I can rule out the water pump since it's flowing through the system, if nothing else?

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

I'm sure I'm just overlooking something, but where are these "rubber water diverters" located? Or should i say, what am I looking for?

 

[daselbee]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Emoney...yes...the thermostats are very tough to get at. They are below the bubble back exhaust chest cover, tucked way up under, and are barely accessible (if at all). Very bad design. Guys have actually drilled the lower cowl to get a socket in there. Putting it back is a very tough challenge, because those springs have quite some minds of their own.

If I were you, I would first get an infrared heat thermometer (30 bucks at HarborFreight), and test the temps all over the heads (not the head covers...the heads themselves) AND get a temp reading on the thermostat housing itself. That is where it should read 140 or so when the motor is warmed up. It will idle cooler than 140, but WOT should not go above 140, 150 or so.

In other words, verify first if the motor is really overheating. The warning buzzers are dumb indicators.

The water deflectors are rubber tubes/hoses that are installed in the cavities around the cylinders down below the heads. You have to take the heads off to inspect them or replace. If the water passages around them are clogged (sand, calcium, junk) it can cause your symptoms. They are only supposed to deflect water in certain specific areas of the innards of that block.

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Glad to hear HarborFreight carries these as they're becoming my favorite store.
I'm assuming I need to put the boat in the water to get an accurate temp reading, or can I do so on the muffs?

 

[daselbee]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Muffs introduce air. Try using a large trash can along with the muffs. You don't have to submerge as far, and the water in the trash can covers the muffs so air doesn't get in.

Or better yet, in the water.

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

I will try to get this done tonight and post my results. Thanks.

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Well, for some reason, I can't get my pics to upload off my phone into my laptop, otherwise, this reply would've been replete with color photos!! Anywho....I stopped and bought the IR Temp "gun" (w/Laser!!!) at HF for $39.95 on sale, plus tax of course....fired up the motor and let it get nice and warm. Sorry, but I couldn't get this beast's lower unit into my big garbage can so it was muffs only. Back to the results: As soon as she started, there was a heavy stream of water coming from both exhaust relief ports, and then after warming up, the starboard side stopped (or slowed to a minute amount) and the port side was starting to slow. Temperature readings where 133-134 degrees on the Starboard side and 131-133 degrees on the Port side. Both sides began to cool a degree or two after what seemed like the T-stats opened so I can assume this means the Tstats are functioning? Since those temps weren't "high", is the consensus that I should just get back in the water and watch what happens?

As a reminder, it's about 3/4 of a mile out the channel at "No Wake". Do these older V4's tend to run hotter at idle? Maybe this had something to do with it? Because again, after I sat a while and let it cool, she purred like a kitten all the way back and it was the same trip coming as it was going, minus the over throttle and porpoising. (I'm also so happy to say she, again, fired right up as soon as I turned the key.....woohoo!!!)

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Ha, figured out my "pic" issue;

As you can see, good steady stream from the tell tale. And, just because I'm proud of it, here's a pic of the boat itself (like that really helps)

 

[emdsapmgr]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Those head temps do not indicate an overheat at idle. Maybe just a little cool, actually. The water flow out of the exhaust relief ports looks normal. It is always possible your overheat was due to running over something-like a plastic bag. When that happens again, make sure you raise the engine for inspection. Those bags tend to hang on if the engine is in the down position and the boat is moving slightly forward. Time to take it out on the water, armed with your laster temp gun. V4's run warmer at idle-all the cooling water must go thru both stats. When you get up on plane, the pressure relief valves open, flooding the powerhead with additional cooling water. Your temps should go down somewhat when on plane.

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Wow!!! Now I've uploaded my very first Youtube Video. Is anybody else proud of me??
http://www.youtube.com/watch?v=WpLRd6oA2G4

Thanks, emd....I've put the temp sensor on the boat and plan to do just that. Hopefully tomorrow night. I still wonder if all the over-throttling/porpoising didn't affect it on the trip out as well. I'm so new to the boat, and any power boat in the Gulf, that I'm hoping it was a lot of operator error. I'll get back to you as soon as I get her out. That's the only drawback to "water-testing" around here. Your choices are to keep it on the muffs and learn nothing, or head out hoping you don't have a major issue. Maybe I can get my neighbor down the street to follow me out and back??

 

[Fed]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

My V4 90 has almost no water coming out of those holes at idle RPM and I've been led to believe that is normal.
If 'no water' is correct then I'd think you have no thermostats or relief valves fitted.
Why don't you test it on the water using a proper trim setting.

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

One final question (for now anyway), is there any chance there is a malfunctioning temp sensor, i.e. warning buzzer? I thought about this when I was out and floating waiting for her to cool. I didn't take the lid off, but the cover sure didn't seem very warm at all when the buzzer did sound and she stopped. I'm assuming these have a pretty strong sensor in them for her to just shut totally off, like you turned the key off, when that buzzer went off. And, tell me if this is right, the buzzer would start to sound as soon as you went to the first turn of the key, the spot before ignition. That's how I knew it was ok to restart, because when I went to the first click, there was finally no "buzzer".

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Yeah, I've seen guys say that "both" are actually correct. When she warmed up, there wasn't any water coming out the exhaust relief. In the video, you'll notice the starboard side port had stopped already. Water test is forthcoming (hopefully tomorrow night)

 

[Fed]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

I believe a lot of water only comes out of those holes at high RPM.
If the motor is still hot then one click of the key will make the alarm sound.
The alarm switch is only for the alarm and it will not stop the motor so you have something else to look for in regard to that.

 

[emoney]

Re: Overheatin question on 140 Evinrude Crossflow

Re: Overheatin question on 140 Evinrude Crossflow

Fed, I think we have different motors, that operate differently (wait...what?). From what I understand, on the 140hp there's an "ignition kill temp switch", that shuts the ignition off to the motor when it gets too hot. Now, I'm never one to disagree when it comes to matters that I know little about, like this one for example. But from everthing I've gleaned from searching here at iboats, and other places, that switch is definitely there. Don't know exactly what determines when it engages, etc.