Genset temperature

[Tenor]

I have a 1965 Kohler 7.5KW gasoline genset - formerly Marine, converted to radiator.  The radiator is remotley mounted in the former air conditioning bay, and the genset is in the first baggage bay.  I just built an enclosure for it and I'm trying to determine wheter or not I need better ventilation.  According to the people I have bought parts from, the thermostat should keep the engine at 170.  So, I'm trying to determine exactly WHERE it should be 170 with my IR gun.  The outside temp is about 65 degrees.

Here are my readings -
Radiator tanks - between 130 and 170
Radiator Lines - between 130 and 170
Engine Block - between 190 and 215 (very close to the water cooled exhaust manifold for the higher reading)

My electric gauge is reading just over 190.  It mounts in a brass extension tied into the cylinder head.  (Could that be giving me a false reading?) I just put a new radiator cap on.  The old one was puking at 180.  The engine is running smooth, without any visible exhaust gas. 

I was getting these readings while running a fridge, 2 roof airs, my Xantrex 4024 in charge mode and it was bulk charging my house batteries.  That's as much of a load as I can imagine running.  Maybe I'm being paranoid, but I'm about to do my first dry camping and I've never relied on my genset and inverter. 
Thanks in advance!

Glenn

[JackConrad]

Glen,
   Temperature senders are usually installed in the engine just below the thermostat and installed so that the thermocouple part of the sender is in the flowing coolant. I would shoot the temperature of the thermostat housing (engine side of the thermostat).
   When does the coolant flow through the exhaust manifold? on its way TO the radiator or FROM the radiator. the coolant should flow through the exhaust manifold on its way the radiator (after leaving the engine), so it does not re-heat the water entering the engine.l  Jack

[Tenor]

Jack,
The cooland does flow from the exhaust manifold to the radiator. That hose shows abut 170. The return line shows about 130. I'll shoot the head at the base of the thermostat housing this morning. Unfortunatly, there doesn't seem to be a spot in the head any closer than it's current location for the thermocouple other than the side of the head. However, it is in a T that I had attempted to run a heater core from. I left it on when I removed the core. I'll get the thermocouple right into the head too and report back. Thanks!

Glenn

[Tenor]

So here's the update.  I moved the thermocouple in and checked the temp on the head immediatley below the thermostat housing.  It reads 190.  My electric temp gauge reads the same or a little less, and the mechanical gauge installed in the side of the head toward the rear of the engine is also reading 190.  The outside temp is 50 degrees.  I'm running the same load on the genset. 

So, it seems the enclosure isn't too much of a problem, but perhaps I need better cooling to keep it at 170?  I'm running an automotive fan pushing air into the radiator and have a squirrel cage fan in an enclosure behind evacuating out the hot air.  Any chance on a hotter day, the genset would just run hotter?  Both last night and today, it sounds great.  No heavy exhaust, no misses.  Maybe I am being paranoid?

Glenn

[Jriddle]

The thermostat in your gen may be a 190 deg. I would check that before you make any changes. Sometimes it is stamped on one side. They may have given you the wrong one. What do you get for reading under no load and fast Idle?

John

[Tenor]

The thermostat is definitley 170.  I bought it from the only dealer in the midwest and it requires a special adpter housing to install, so no doubt there.  I have not tried running it witout a load.  I'll try that and post.  Thanks!

Glenn

[Tenor]

OK -
After further testing, it runs right about 170-175 under a light load according to the gauges.  Light load being the inverter charging house batteries.  Looks like it's going up to about 180 with an air conditioner on.  Thoughts?  Thanks!

Glenn

[JackConrad]

That sounds about right for engine temperature.  If you are concerned about compartment temperature (as opposed to engine temperature), you can remote the radiator to a position out side the compartment and greatly reduce the compartment temperature.  Jack

[Tenor]

Jack,
The radiator is remotely mounted.  It's about 2 feet away from the genset and they have seperate enclosures/shrouds.  Do you mean that running around 190 under a full load is OK?  I just want to be sure.  I'd hate to have it start creeping up above that if the outside temp was 95.  I really appreciate the advice!

Glenn

[JackConrad]

Most water cooled gasolene automotive engines are OK to about 220-230 depending on the how much pressure the radiator cap is set for and usually run abouy 180-210, so I would think that should be fine for your engine.  Maybe someone more knowledgeable about Kohlers will reply.  Jack

[Blacksheep]

Going down the road my gen runs anywhere from 180 to 190 depending on how hot it is out side. Sitting still it runs a constant 180. I have a large squirrel cage fan bringing air in from underneath the bus on the curb side directing that air thru a bulkhead directly over generator head and then I have an electric fan pushing air OUT away from radiator thru another bulkhead and back down thru the floor exiting the bus underneath on the drivers side.

Couldn't tell you if this is the right way or not but it has worked very well for the last 6 years!

Ace

Oh it's a very old 12.5 kw kubota made by Wrico that we we fortunate enough to keep from our other bus!

[Tenor]

Jack, - I'm running a 13lb cap.  Still OK?  Thanks!  Ace, I'm not sure how to apply your knowlede here, but I appreciate it!

Glenn

[JackConrad]

Jack, - I'm running a 13lb cap.  Still OK?  Thanks!  Ace, I'm not sure how to apply your knowlede here, but I appreciate it!
Glenn

Should be, the higher the pressure, the hotter the water can be before it boils.  Jack

[Tenor]

Final update (I think! )
I bypassed the water cooled manifold and what do ya know - with 2 roof airs, 4024, and fridge it stays at 170-175!  I attempted to run it without the pusher fan, but the temp climbs back up to 190.  The pusher fan will bring it back down slowly.  I now need to put a temperature controlled switch on the pusher fan to automate that system.  Thanks to everyone who helped!

Glenn