GENSET RAN HOT

[sivrtnge2]

I decided to take the coach out for dinner and bowling on Thursday night. I ran the genset for approximately 2 hours. As we pulled into the parking lot i could smell anti freeze. I checked and noticed blue color smoke from the genset exhaust. i checked the temp gauge and saw that it was passed the 250 degree mark. i immediately shut the genset down. I checked for leaks...found none. I checked for water in oil...found none. i checked for oil in water...found none. i started the genset yesterday...the exhaust was clear and the temp was around 180.  Please give me suggestions as to what it could have been and what damage might have transpired? it as a 20kw powertech. 

[H3Jim]

Where is the radiator located, and what direction does the fan blow air through it?

Check the airflow through the gen set radiator.  I suspect that when the bus is moving, that air currents prevent air from passing through its radiator.  It that's true, you might try reversing the fan so it doesn't fight the flow through it.

[Len Silva]

As well as figuring out wht it overheated you need to find out why it didn't shut down.  I'm quite sure that all Powertechs have a shutdown circuit.

Len

[sivrtnge2]

Ok. I found my belt was broken, lying in the bottom of the shrowd. I also found that the water travel outside of the genset under the coach and back to a second reservoir between the drive axles. This coach was built by Cauldwell Coach. Is this normal

[sivrtnge2]

I put a new belt on today. I ran the unit for about 20 minutes. It ran hot again...I noticed smoking onthe left side (exhaust side) of the engine. It was definately a steam type smoke. I guess need to start looking for someone locally to check it out and probably rebuild it. I just dont understand...it runs so smooth and quiet. no skip, sputter, or nothing!!! Someone please give me more insight!!!

[JerryH]

Sivrtnge2:

I had a genset issue recently as well.
Was at Penn State tailgating, genset was running -- before then, never really had any issues with genset, but then again ... never really did fully go over it as I should have.

So the genset is running, then I hear noise and start to smell a smell -- coach door was open.  I run out and it's over heating ... antifreeze running out, the works.  I immediately shut down the genset.

I wait until it cools.  I check the coolant levels and they're waaay down.  I check the oil and it's low as well.  I am thinking, "Oh crap... hope it's not screwed."  After it cools, I add necessary coolant and oil.  I start genset again, it runs fine.  I keep an eye on the temperature gauges inside the coach. Within short order, it's encroaching 200.  I shut it down.

When I return to home, I start to troubleshoot it.  I find a leak at the top of the rad along a seam.  It was shooting coolant all over the flex exhaust.  You really couldn't see it when the genset was retracted inside the coach -- but once the exhaust got up to temperature ... you could see and smell the coolant shooting on the rad.

Suffice to say ... the rad needed to be re-cored, which we did.  Found a kink which leaked exhaust into the baggage bay -- took care of that.  We were on a roll and kept on going with fixes.  The genset operates fine now.

I know you've probably checked these but ... I'd replace the thermostat, or at least test it.  Check the rad for leaks.  What about the coolant water pump?  Our genset, once started, kicks on a squirrel cage which draws in exterior air, across the rad, then out the bottom of the coach.  If yours has a similar type blower, I'd check to insure that no air flow is impeded.  Although you said fan belt, so I assume it's a typical fan attached to engine at the rad?

When we re-cored the rad, they tested it before doing any work.  They called me and told me it tested at less than 70% -- not sure how they test it, but clearly 100% is better than 70%.

Good luck,
Jerry H.

[sivrtnge2]

Can the engine be pressure tested???
--
BILL

[bobofthenorth]

sounds more like a leaking rad or rad hose to me - but I'm a long ways away and guessing so ultimately its just a WAG

[sivrtnge2]

THE GENSET IS FIXED . COST ME A FORTUNE  ::(A CHINESE BUFFET DINNER AND 2 GALLONS OF ANTIFREEZE). It was an air bubble in the system. GO-FIGURE !!!
--
BILL

[TomC]

That has happened to me twice with my 10kw Powertech.  Once on initial start up, and second time when changing the anti freeze.  Both times had to start and stop to "burp" the engine about 6 times before it decided to run right.  On the top of the thermostat housing is a release twist valve.  When the engine starts climbing, shut it down and slowly (with gloves on) crack that valve until coolant comes out then close and restart.  Takes a few minutes but eventually will start working correctly.  Good Luck, TomC