3208 running hotter than it should

[steve miller]

I know these engines run on the hot side for diesels. Under load (steaming)
she got up to 195 running her around to Old Harbor from New Harbor (B.I.). She ran at 180 last year. We just put a new impeller and thermostats in, and cleaned the heat exchanger. Aside from a faulty sender or gauge, what the heck could it be?????????????

I came here with this question, due to the high quantity of engine genius types!! :)

[Bob H.]

Steve, Impeller in one piece when it came out? If no, maybe bits plugged up cooler. Zincs in one piece? Intake good and clear? Screen or strainer? I had an I/O that ran hot turned out to be shellfish that grew in the oil cooler, shallow slip stirred up mud every time, that mud had tiny shellfish, plugged up cooler but good. Got a laser temp gun? just to double check your gauge reading. BH

[Brewster Minton]

New thermostat is wrong setting??

[steve miller]

the impeller came out in one piece, I have a laser gun (which I have not yet used to check with), and the pencil zincs were in one piece. The intake drew water freely in my yard before launching. The thermostats are 180 degree u nits, as per factory........wtf!!!!

[In Memory Walter K]

Make sure the intake hose on your raw water pump is not worn/frayed where it is clamped down. I had air seep in at high rpms, thus lessening weter flow. Any doubt, cut it back and reclamp.

[Bruce]

Look at the raw water hoses to see if they look bloated over normal size, it could indicate a blockage in the raw water circuit all the way to the risers.

Also if this is your first real time running it after the thermo install you could have air in the closed system. From time to time I've had issues with 3208's and getting them bled properly even with the bleed valve on top.

Did you check the pump cam for finger wear?

Does the exhaust steam at cruise?

[TailhookTom]

Steve:

I had the problem Walter referred to -- clamp wasn't tight enough and temp ran a little hot. Replaced the worn clamps and cooled right back to termostat operating temperature.

Tom

[capt2kids]

Both engines doing the same thing? Hotter than before?
Use the laser gun, my 3208's said running at 190, but with laser gun, both running at 170 at cruise, and 165 idling along.

[steve miller]

That's some good info...thanks!! The raw water intake hose has a frayed end, it's in crappy shape. I had no idea air needed to be bled from the cooling system!! (ahem). I didn't see any steam at cruise from exhaust; there seemed to be a good flow of water, and it was lukewarm. Also.....pump cam? finger wear? I'm clueless!!!

Another thing, I didn't use muriatic acid when cleaning heat exchanger.....gonna get some & try that.

Again, thanks for heading me in the right direction.

[Capt.Frank]

I don't know how the risers are on the TA, but my risers we clogged up bad last time I had temp problems. Changed the risers and temp dropped back to 170-180.

[steve miller]

I don't know how the risers are on the TA, but my risers we clogged up bad last time I had temp problems. Changed the risers and temp dropped back to 170-180.

I guess I'll take a peek at the risers as well. BTW, what were yours clogged with?

[Capt.Frank]

I guess calcium? I don't know realy. I know gas motors only get 5-7 years around here. I got over 20 on 3 out of 4 not bad. Here are some pictures of mine. The new ones were a different style then these two clogged ones with small holes.

[steve miller]

It seems that the temp sending unit and/or gauge is bad. Once I washed the heat exchanger w/muriatic, I fired her up & headed out. It went right up to 200 degrees and beyond. But when I shot the engine with the temp gun, it was under 180!! I have a new mechanical gauge & sender which'll go in as soon as the rain stops. Thanks again for all the help.

[Charlie]

I have a set of mechanicals in the engine room. When in doubt look at the mechanical gauge. The IR gun is a great tool as well.