One bank alot hotter then the other.

[Franki]

Hi guys, <br /><br />My V4 has a problem at the moment.. <br /><br />The Starboard bank is much hotter then the port.. <br />even after only 2 minutes of running.<br /><br />I can keep my hand on the port side more or less indefinately.. but the starboard side I can only keep my hand on for a minute or two..<br /><br />This is on water muffs, so its possible that I am just not getting enough water up there..<br /><br />Should I be looking a the thermostat here????<br /><br />rgds<br /><br />Franki

 

[ob]

Re: One bank alot hotter then the other.

May very well be a thermostat issue with the bank that seems to be running hot.Was this determined by a touch check on warm engine?Should run around 145 degrees or so depending on model and make.Perhaps the cooler bank is running too cold if you can leave your hand on the head cover indefinately.A specific make , year model, and horsepower would be beneficial.

 

[Franki]

Re: One bank alot hotter then the other.

My Name is the engine model.. 100ESL72. 100HP Johnson 72 model.. <br /><br />and I meant to say that the starboard bank can only hold fingers on for a 2 or 3 seconds. not minutes..<br /><br />I am disconnecting the water hose from thermostat to starboard bank, and going to try and flush it. (hook up hose to the head.. see if it flows freely.)<br /><br />For the thermostat to be feeding the port bank, shouldn't the starboard be getting fed as well?<br /><br />I have two temp guages, one on each bank, problem is one is Celcius and the other Farenheit...<br /><br />I don't know F... <br /><br />This was tested by putting my hand on the head after running on water muffs for 2 or 3 minutes...<br /><br />Water was exiting out of the outlets correctly, I am thinking perhaps its just not getting enough water up on the muffs..<br /><br />Had revs stilling at about 1200 rpm for two or three minutes before testing for heat...<br /><br />Any ideas???<br /><br />regards<br /><br />Franki

 

[OBJ]

Re: One bank alot hotter then the other.

Hi franki...judging from your handle - franki100esl72 - I'm going to say you have a OMC product 100hp. Port side on the V's generally run a little cooler than the starboard side. From what you said, you can keep your hand/fingers on the port side pretty good but can only for a couple minutes on the starboard side. If the engine was running good temp measured from the flat area just behind the top of the head, it should be in the area of 140 to 145 degrees. You can lay your finger on it and it will get uncomfortable after several seconds. From what you said, it would appear to me that both sides may need T-stats on both sides as they are not warming up at all or very little. On the other end, there may be nothing wrong at all. Have you checked it under way and have you ever gotten the over heat alarm?

 

[ob]

Re: One bank alot hotter then the other.

Engine needs to be in water,under load ,to verify whether temp is excessive.A thermo melt stik of 163 degrees is a quick easy test.If you are unsure when thermostats were last changed they're due.

 

[Hooty]

Re: One bank alot hotter then the other.

Sears has a non-contact infrared thermometer that reads in F* and C*. Here in the U.S. it sells for $80.00. Real handy tool.<br /><br />c/6<br /><br />Hooty

 

[Franki]

Re: One bank alot hotter then the other.

Thanks guys, <br /><br />I get one of them temp gun things I think..<br /><br />could prove handy in future..<br /><br />regards<br /><br />Franki

 

[ledgefinder]

Re: One bank alot hotter then the other.

Post-1977 OMC V4s had a separate themostat for each bank, your's has same system for both sides. Manual says, as stated, cylinder wall should be about 140 degrees, you can set your hand on them for about 5 seconds.<br /><br />DHadley & others who actually know what they're doing get concerned about running too cool - leads to wear. I, who don't know squat, think about all those thermostat-less Mercs up until the 1980s and don't get too wound up about it. Sounds like you're running too cool, maybe losing some power, smooth idle, wear concerns, etc.. <br /><br />On the other hand, you're in Perth, Australia in February - sun, 19 year-olds in bikinis, etc.. Here in the eastern US, we have 4 feet to snow on the ground with more forecast.

 

[Franki]

Re: One bank alot hotter then the other.

Incidently guys..<br /><br />I just checked, I think the problem is that the muffs are not sealing against the leg properly...<br /><br />I just left the engine at a fast idle. (nearly 1500rpm) for 20 minutes and the starboard bank got no hotter... still I could not keep fingers on without some pain for more then 3-5 seconds..<br /><br />The temp guage on that cyl indicated about 140-145, so I am guessing thats alright..<br /><br />Still, the other bank was alot cooler. It was warm, but had no problem keeping finger on it.. <br /><br />the only thing I can think off, is that I had the port bank head off two days ago, and cleaned it right out, all the water channels and removed carbon all around.. but that shouldn't be making that much difference.. I'd guess the temp diff is about 10 degrees.. does that sound right?<br /><br />rgds<br /><br />Franki

 

[OBJ]

Re: One bank alot hotter then the other.

Franki...get it on the water as ob suggested. I don't think you have a problem but check it out just to make sure and make yourself comfortable with the engine.

 

[Franki]

Re: One bank alot hotter then the other.

Thanks guys<br /><br />This is my first time out on the boat in almost a year.. wish me luck...<br /><br />Its also the first time I've had a tacho, speedo and two temp guages... so I should be fine.<br /><br />Thanks again.. keep your fingers crossed for me, in an hour I will be on the water.<br /><br />Also, I just checked, the over heat alarm works, I disconnected it from the head and earthed it.. the horn went nuts, so I think we can safely say its working..<br /><br />regards<br /><br />Franki

 

[93bronco]

Re: One bank alot hotter then the other.

just a quick note- if you plan on running on muffs for anything other than a quick flush i would get one of those flushing mufflers from overtons.com about $43.00. really helps with the backpressure and keeps noise to a minimum. and than still i wouldnt run it to long on that either. or get a big enough container to use as a make shift test tank, which is the best way if not in water.