Generator shutdown

Desertrider · 06-28-2010, 11:36 AM

I have a 2007 Sightseer 30B with the 4000 Microquiet Generator. While driving the motorhome, the generator shuts itself off in temperatures above 95 deg F.The oil level is good, the air filter has been replaced. The only thing I see is that the air intake panel on the generator housing is very close to the side access door on the motorhome.
Could it be that while driving the air needed to cool the generator is being sucked away as we drive? Possibly a vacuum situation.

Desertrider

**RV Wizard** · 06-29-2010, 02:38 AM

Hello Desertrider and welcome to iRV2.com. We are glad to have you join us here and we look forward to reading of your adventures and experiences. I am sure you will enjoy the website and forums. Take care and keep us posted.
One thing I have learned is "anything is possible". I am sure you have the access door properly in place and that the gaskets are in good condition. You may want to experiment a little and fabricate a scoop that would force air into the generator as you drive and see if that correct the over heating issue. Good luck and let us know how you come out.

Desertrider · 06-29-2010, 01:28 PM

Thanks for the support RV Wizard. I have a plan in place for that very scoop!

Free Bird · 06-30-2010, 11:56 AM

Hello There, Saw the problem you are having and thought this might be worth a try. Had same problem. Gen would shut down while riding. Took to dealer for $500. service. Same problem again. They replaced carb, fuel filter, plug, adjusted reed valves, oil, etc. Ran good until next long trip. Same problem again. This time 1000 miles from home. Runs out after fuel up and about 3/4 full tank. Now what.?? Pickup tube too short ? Can't access top of tank. Fuel line cracked or plugged? Seems Ok, but would require major job to replace. VOILA !!!!! Guess what. Former owner replaced fuel cap with locking cap. I always hated those. Replaced original cap and BINGO, works fine. Must have not been cap was not venting, and after 100 miles or so, there was too much vacumn in tank caused by main engine drawing fuel and generator pump unable to pick up fuel as it is only about a 2 to 2 1/2 pound pump. HAVING PROBLEM ? change fuel tank fill cap. Besides, locking caps are an invitation for a desperate thief to punch a
hole in bottom of fuel tank and take what he wants and let rest run out on ground.
P.S. I do hve a Microquiet 4000 in a 2001 Georgetown Class A

AFChap · 06-30-2010, 12:06 PM

An Onan generator will normally have an error code when it does an unplanned shut down. The code is read by a series of blinks on the start button. If you check your manual, it should tell you how to check for the code, and then how to interpret it to find out what it is telling you. That would save a lot of guessing...

Desertrider · 07-06-2010, 09:49 AM

Thanks AFChap. I appreciate you help.

Although I did fabricate a duct system and it seemed to work well, we are still having the same problem. I looked for a fault code within the 5 minute window. None found. I'll be taking it in to the dealer this week. Have a long trip planned at the end of the month, so need all systems go.

RVDude · 07-06-2010, 10:16 AM

desert - You'd be getting a fault code (the flashing light code like afc said) if it were a high temp shutdown or any other Genset triggered shutdown.

I think freebird has your ticket! Try leaving your gas cap in but not anywhere near tight and go for a hot drive and see it that does the trick. If so, hit a NAPA and get a new (vented) cap. The genset electronics will not know of a fuel starvation situation and will not flash a code but the genset will sure shut down.