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Topic: Onan 6.5nh-3cr/16004p  (Read 381 times) previous topic - next topic

Onan 6.5nh-3cr/16004p

I have a 1986 GV with a 6.5 propane generator. When the generator is running, it is louder than normal and exhaust is not coming from the exhaust pipe. The exhaust is coming out the left side bottom of the generator which looks like a blower, so my first thought is that i am missing a plate that covers the blower making the exhaust come out of the exhaust pipe. I got under there today to check to see if the exhaust pipe was connected properly and it appeared to be connected, but it was difficult to maneuver under there so i am not 100% certain. I will take a pic in the AM, but just wanted to know if the exhaust should be coming out of the bottom of the generator at all? Or if i need to inspect the connection again?
1986 GV 36' w/ 3208T Cat
Build #2614

Re: Onan 6.5nh-3cr/16004p

Reply #1 –
The blower you see is the cooling fan as that generator is air cooled. The opening you see needs to be left open to properly cool the unit. Now the exhaust pipe is most likely broken inside the case. You will need to remove the covers and see if/where the exhaust is broken.  This sure needs to be looked at before the exhaust escaping could cause overheating of the electronics.

Mike

 
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Onan 6.5nh-3cr/16004p

Reply #2 –
Or fumes in the coach.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Onan 6.5nh-3cr/16004p

Reply #3 –
Quote from: John44 –
Or fumes in the coach.
Absolutely, the exhaust needs to go outside coach.  Do not use until fixed.  Carbon Monoxide will kill you.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Onan 6.5nh-3cr/16004p

Reply #4 –
And, if your Onan is like mine, the absolutely deafening noise is coming from the fan air intake.
The exhaust is not the culprit on these models.
It is so loud that we can hear it running almost a city block away from the coach.
Relining the compartment doesn't stop the noise. I tried that. No luck. also
I also added an extension to get the exhaust out from under the coach and away.
The noisy cooling air intake can only be reduced by adding external baffles to change intake sound direction. Each 90* change in a sound wave will reduce the decibels.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Onan 6.5nh-3cr/16004p

Reply #5 –
Quote from: Michaelther4 –
.... and exhaust is not coming from the exhaust pipe.

THIS is the critical bit of information. The noise issue is secondary.

As already mentioned, this is an important safety issue.  Carbon monoxide poisoning should not be taken lightly.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Onan 6.5nh-3cr/16004p

Reply #6 –
Quote from: Michaelther4 –
I will take a pic in the AM, but just wanted to know if the exhaust should be coming out of the bottom of the generator at all? Or if i need to inspect the connection again?

The exhaust comes out of the exhaust pipe.  The flywheel has fins that draw cooling air over the finned cylinders and exhausts the warmed air straight down onto the ground.  There's a black plate on the top of the engine that will give you access to the intake and exhaust pipes.  It's solid pipe all the way around to the end of the muffler so if you can wiggle the muffler, the pipes broken.  But then again the muffler is bolted solidly to the engine.

Who did you choose as executor?  Asking for a friend.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.
 

Re: Onan 6.5nh-3cr/16004p

Reply #7 –
Thank for all of your input.  I believe I have figured out what is going on.  Where the exhaust pipe coming from the generator goes into the muffler the end cap has come off of the muffler, so the exhaust is coming out there prior to going through the muffler.

Mike T.
1986 GV 36' w/ 3208T Cat
Build #2614