Multi Symptom Generator problem

[jmacstack]

I have 20 Kw Kohler Generator in my 1987 Newell. Here's the issue: Sometimes it will start up just fine from inside the coach or at the generator itself. If I shut it down and try to restart, it will run at slow idle and run for a few seconds, up to 30 seconds(appx) and then shut itself down. This happens hot or cold. During this slow idle period, I am unable to shut it down using either switch. Sometimes when I try to fire it up, I get nothing but a click. I fired it up the other day to go 3 miles to a business and when I got to my destination, it had shut itself down. When I was running it those 3 miles the oil pressure gage on the instrument panel for the generator was pegged off the scale. I have replaced the merge solenoid. I have replaced the fuel relay in the controller box on the back of the engine. I have recently changed the oil and all fuel filters. I have cleaned all grounds I could find. All fuses are good. House batteries are charged. Does anyone have any clues about what I can try next? Thanks, Jennifer

[encantotom]

hi jennifer. a few questions.

1. a 20kw generator is not the normal one in a 87, a 12.5kw one is. so is the engine a yanmar? once you get it working, i have some questions about how it is integrated into the coach, but those are for later.

2. a simple question, but you are using the switch to "warm" up the glowplugs for 30 seconds of so before you start it, right?

3. when did the problem start? after doing any of the service?



tom

[Richard and Rhonda]

Jennifer,

Look at the solenoid that turns the fuel off and on. I had similar issues. Mine would start and stumble. And then one day it wouldn't stop running. It turned out the rod from that fuel solenoid to the lever on the fuel injector pump had come loose.

The solenoid is kind of hidden, but it is on the side of the engine with the injection pump. Look for a round solenoid, an adjustable rod coming out of it that is connected to lever that moves back and forth.

I'll send you a PM with my cell.

[HoosierDaddy]

Hi Jennifer,
I would investigate the oil pressure gauge issue. I think it is set up so that if the oil pressure drops it will shut the engine down. Check oil level and viscosity first, then the oil pressure sender and related wiring. I have found that my '78 Newell relies on 12V from the chassis batteries to activate the fuel solenoid.
Good Luck,
Dean

[HoosierDaddy]

Also...My 78 has a glass fuse located on the back side of the front panel of the box on top of the generator (12Kw Kohler/Perkins). You cannot see the fuse. I was having similar start/run problems when a bit of corrosion caused an intermittent 12V supply through that fuse. I found that there was no 12V supply at the dash switch when the fuse was malfunctioning.

[jmacstack]

Thanks for all your ideas. Tom, this coach was re-powered and yes it is a yanmar engine. I serviced this with the previous owner in Ohio,(Walter Preston) before we headed home to Montana. All systems were good to go. The problems started in Iowa.

Dean, I have isolated my fuel solenoid power origination and it is from the house batteries. I have checked and re-check that glass fuse.

Here are some more thoughts: I have zero resistance to the hold in coil at the fuel solenoid. I do not have 12 volts from the control box to that lead. How is this possible? If I had power I should have no resistance. Early on in this dilema, I checked the house batteries. There was no noticeable water in ANY of the center cells of ALL batteries and there was a bit of water in the rest of the cells. I put almost 4 gallons of distilled water in these batteries which are 5 years old. Could this be the culprit? I have not had them load tested. I now have the coach plugged into 50 amps and am waiting to check on if they can receive a full charge. I may have to replace them. The 2nd leg light on the panel above driver's seat is flickering and the other leg light is strong on.

Richard, I have ordered a new fuel solenoid to the tune of $238.00. Seems a bit steep to me. However, if I am not getting 12 volts to the hold in lead of that solenoid, replacing it will be futile. I was recently told that 6 volt deep cycle batteries are better than 12 volt. Currently I have 12 volt. If I have to replace the house batteries, should I replace them with 12 or 6 volt?

Thanks for weighing in on this head scratcher. Jennifer

[fulltiming]

I am not sure which batteries the 87's used. If they are 4-D's or smaller, changing to twice as many 6 volt golf cart batteries would work well for the house batteries. The 90's models use 8-D's and I have had great luck with the AGM 8-D's. They are expensive and heavy but they hold up well.

[encantotom]

gee, maybe having been in iowa was the issue? sucked some corn in the genny? (thats from an iowa boy). the coaches i have seen of that year have had 8D's. with the coaches that have battery boxes versus pull out racks the issue is making any battery other than the original size fit in that box.

wallys 88 has has battery boxes that stick up, mine are recessed. i considered putting a different one in but it wasnt going to fit. so i found a deal on 8D AGM's of 400 each and put them in the coach side. i was a cheapskate and put regular batteries in the starting side and got them at Sam's club for if i remember right about 130 bucks apiece. interstate brand.

btw, the 8D's weigh over 150 pounds apiece, so get some help to take them out and put them in. the 6v deep cycle are easier to find by far but you will have to make new battery cables as well.

the lead acid batteries do not like to be charged with no fluid in them and will destroy themselves. if they were dry and had been charging, good chance they are toast. load testing is not as easy as you would think since you either have to drive the coach somewhere and unhook the battery or take it somewhere.

the flickering light on your panel is nothing more than the light ending its useful life. i have replaced all mine and most of the gang here has replaced a few of them. they are 2-3 bucks each if you know where to buy them. (we can help with that)

tom

[fulltiming]

Jennifer, you mentioned that you had double checked the glass fuse. I would try replacing it. I have seen fuses that looked good, ohmed out OK but failed under load. Not typical but it can happen.

[Richard and Rhonda]

Jennifer,

Disconnect the arm on the solenoid and open and close the fuel shut off arm manually to see if that remedies the problem. If it does or doesn't that will help in the diagnostic.

[Wally Arntzen]

Jennifer, my 88 has 8D batteries. I replaced all of them with Catepiller maintainance free ones and also use the power pulse battery saver to extend the life of them. These batteries cost in excesss of 550.00 each but are super batteries. I have been using the power pulse saver long before Newell started putting them in all of there coaches. They are less that 100.00 each and they really do extend the life of a battery.
Tires and batteries are costly items but both are extremely necessary to be in good condition when running these coaches.
There are a lot of options on batteries but I strongly recomment that you get as good a battery as you can afford.

Thats my opinion and i'm sticking with it.

Wally

ps, Tom is a good friend who has spared no cost to make his coach beautiful with no cost sparred and I don't understand why he admitts he put in cheap batteries. LOL

[prarieschooner]

Changing out Batteries can be a very expensive proposition and you just purchased the Coach. Basically there are two types of House Batteries that I would choose Flooded Lead Acid (one that you add water to) and Absorbed Glass Mat (AGM).
When you stated 6 Volt you were most likely talking about Golf Cart or Deep Cycle Flooded Lead Acid Batteries. This type of Battery is relatively inexpensive while the Charging System of your Coach is probably already set up for them.
The AGM is a sealed Battery and has an Extended Life if taken care of properly and these are getting more popular. The AGM Battery is much more Expensive and the Charging System should be set up for this type of battery.
When you get to the Staring Batteries I am not sure that it is worth the Extra $$$ to go with AGM Batteries. A good pair of 8D Batteries is hard to beat and you can get a deal on them at any Battery Dealer. I paid about $125.00 each for a Commercial Grade and plan on changing them out in a couple of years.
For the House I chose to use TROJAN T105 6 Volt Batteries and paid around $125.00 each with a total of 4. These are much easier to lift than an 8D and usually last much longer if taken care of (check the level and use Distilled Water). These should last between 3-5 years with care but I have some that were installed on my Boat that are still in good condition after 7 years.
Since you just bought the Coach I would recommend that you replace the Batteries with ones of the same type. You can always up-grade to the AGM type in a few years and they will most likely be less $$$ because there are more resources for this type of Battery every day. You will also be able to replace the Charging System over time and not need to incur the Cost of replacing both at the same time.
This is my Opinion and like Elbows we all have them.

[encantotom]

I did put in AGM batteries as i said in my coach side. i was able to find a smokin deal on them of 400 each, but i did have to make new battery cables as they were lugs versus A posts, but i kept the old cables so i can switch back if i need to.

the "cheap" batteries were still high quality interstates for the starting side. it would have been nice to put agm's there too, but as wally said, i have spared no expense in many regards in refurbishing my coach, and i chose to put the money elsewhere....oh yeah, that was for my kids in college....

put agm's in the coach side and it will be best as long as your charger can charge the agms right, for the starting side do what you can afford and feel good about.

i also put in the power pulse units on each bank of batteries. i know wally has one on each battery, so he gets double goodness. they are supposed to make the batteries last twice as long by desulfiding them.

or do whatever you want as long as you feel comfortable with it.

and as wally has taught me to say....thats my 2 cents worth and i am sticking to it"

btw, wally has really spared no expense on his coach as it is BEAUTIFUL and has lots of upgrades he has done.

mine is just a heavy camper in comparison......

tom

[jmacstack]

Hello to all who have have shared their ideas, questions and expertise on my multi-symptom generator problem. Here is the solution!

1. Purchased 6 new 12 volt deep cycle batteries for the house. Ouch!
2. Added a batteryminder. Well worth the $99.00(Northern Tool)
3. This generator has 1304 hours on it. I was looking hard at the fuel solenoid, the K25 relay which feed the fuel solenoid(replaced with new) and possible causes of low-voltage to the control box. Here's the fix: The fuel solenoid arm is attached to the fuel solenoid on one side(left) and the other side(right) is linked directly into the fuel pump. The shaft inside the fuel pump has a spring and a(shoot can't remember what it's called) but it fans in and out in a circular motion to activate and de-activate the fuel pump. This particular apparatus spins on this shaft. If the generator is run for long periods of time with no load variation the shaft will wear a groove around in one spot causing this circular apparatus to hang up in start up as well as shut down on the groove that is created by constant spinning in one place. The repair is a removal of that side of the fuel pump and rebuild and re-install. The action of fuel solenoid arm is very sticky and does not feel springy at all. Since I ordered a new solenoid I knew what it was supposed to feel like. There is also a spring in that side of the fuel pump which could break which would cause the same symptoms and stickiness.

Lesson: Do your laundry, turn on all lights, watch TV and cook all at the same time to load that genny up!

This repair has been a head scratcher and I hope posting the solution will help someone else from going bald! Thanks a million for all you help! Richard you were in the right area right out of the starting gate!

[Richard and Rhonda]

Absolutely,

Thank you so much !!!!!! Not only did you post the fix, but you gave plenty of details on what to look for. YOu have officially lost your rookie status :-)

You rock !!!

My gennie is sometimes recalcitrant on starting, and I have focused on the solenoid. I now will move it by hand and see if it has the sticky syndrome.

[encantotom]

Richard is always spot on. thanks Jennifer for posting what fixed it.

it is great to have another person to guide us on how to fix stuff.

later

tom

[tuga]

My generator problem is a little different:

1. In 93 degree ambient temps my gen runs at 210-225. It will run for 48 hours like this. However at night it does run at 180 when ambient temps fall to 77 degrees.
2. If ambient temps get hotter it shuts down at about 230 degrees; this is probably right.

This morning, after running for 48 continuous hours, it slowed down, strained a little, then died. Ambient temps were 88 degrees and since it was early morning the operating temps were 175-180. I checked oil and water - all o.k. I started it up and it ran for another 30 minutes (operating temps 175 degrees) ambient temps 88 degrees. It stopped again after about 30 minutes so I just left if off.

It used to run all day at 180 with ambient temps 70 degrees
then 200 with ambient temps 80 degrees
then 210 with ambient temps 90 degrees
then 225 with ambient temps 93+ degrees

So it looks like I have TWO PROBLEMS:

1. Overheating during hot ambient temps
2. Shutting down for no apparent reason

Any suggestions?

[chockwald]

I'm assuming your genset is a diesel, so I'm not sure what optimum operating temp should be, but 220+ seems high. I would not think it should go up that much even with temps in the 90's. Mine, which is fueled by propane, runs constantly at 180-185 when it is 70-100 outside.

[HoosierDaddy]

Tuga,
Shutting down sounds like a fuel problem. I would check:
the fuel filter etc.
the fuel rod solenoid
the Murphy switch

It seems that the cooling ability is marginal so it might be time for cooling system maintenance. I dont think it should ever run over 200. flush and clean radiator, new thermostat, belts and hoses, water pump. Check squirrel-cage fan..make sure it is running up to speed, belt, bearings etc.

These two problems may not be related.

[fulltiming]

I concur with Dean. Your generator should not be running that hot so the generator radiator and fan would be the two primary suspects. I find that load makes more difference than ambient temperature on the generator's operating temperature. With only 2 air conditioners on, mine will run at about 180 degrees at 80 degrees or 100 degrees outside. When I turn on all four airs, the temp will go up.

[tuga]

I concur with Dean. Your generator should not be running that hot so the generator radiator and fan would be the two primary suspects. I find that load makes more difference than ambient temperature on the generator's operating temperature. With only 2 air conditioners on, mine will run at about 180 degrees at 80 degrees or 100 degrees outside. When I turn on all four airs, the temp will go up.

Michael,

This past weekend when we were tailgating in Baton Rouge all four compressors were running all day. I have 2 basement SCS double compressor units. In moderate temps only 1 compressor will run, but when the temps rise the second compressor will kick in.

It was 93 degrees and humidity was about 85% this past weekend! In addition the parking space that I was in only allowed 2" of air space between the concrete and the generator oil pan!

In those conditions, what do you think your generator operating temp would be? Mine was at 225 degrees. At night, the operating temps went down to 180. Do you think that I have an overheating problem? Or was it just too hot for a gen to run under those conditions?

[Richard and Rhonda]

Tuga,

Sounds like you were putting a major load on the gennie with all four AC's running, people in and out of the coach, and no cooling space. The temp and humidity you quoted puts a big load on the AC units.

The gennie slowly stumbling and stopping sounds like a fuel problem. If the overtemp sensor kicks in, it shuts the fuel solenoid off, and the engine will stop quickly.

I would replace both fuel filters as my first order of business.

[tuga]

I'll be doing that this morning Richard. I know that the ambient temps were high but I have been using the coach in this parking spot for the last 5 years, and this is the first time that the operatiing temp was this high. After I change my filters and oil this morning, I am going to test the operating temps again by letting it run for a few hours with the front end lowered all the way down to simulate the parking spot at LSU. If it overheats again (which I think it will) I will start to examine the thermostat, remove radiator and have it rodded and cleaned, & check the blower for proper air flow.

Tommy at Newell suggested reducing the air intake in the p/s bay by installing a piece of aluminum that would cover half of the vent in the door. I will try that if the above fails.

I agree with you and others that it is a fuel problem. I have ordered a new 12v fuel pump from Kohler and if that doesn't do the trick I will check the water pump next (thank you HoosierDaddy). Some of my Prevost buddies have had this issue and in all 3 cases the fuel pump was the culprit, so that is why I am attacking that first.

How is your project going with your series 60?

[tuga]

How do I go about testing my water pump? And where is it located on the generator?

20 KW Kohler (Model # 20CC067-RV)

Thanks,

[Wally Arntzen]

Tuga, it may be the fuel filter. I have been dealing with this fungas problem for a couple of years and a couple of times mine would go into a hesitation mode and changing the filter always sloved the problem. I run mine with all three air conditioners and the electric heater on and never go over 185 degrees regardless of the outside temperature.
I think if you are starving the unit due to a bad filter it could affect the temperature.

[HoosierDaddy]

Tuga,
The water pump on mine is belt driven on the front of the engine directly behind where the radiator fan would be mounted on a conventional application. The first indication of a problem will be coolant seepage around the shaft where it enters the pump body. I remove the radiator cap (before the engine heats up) start it and allow it to reach operating temp (coolant will probably "boil over" the radiator as it warms) If you monitor the temp of the upper radiator hose you can tell when the thermostat opens...it will get hot almost immediatly....I just touch it every minute or so and can feel the difference. Once the thermostat opens you will be able to look inside the radiator and see the coolant circulating. If that all checks out the pump and thermostat are probably working properly. To avoid any problems "on the road" I just replaced the pump,hoses,belts and had the radiator cleaned when I first bought my '78 because it had high hours on it. Once you have it all apart it's not hard to do.

[tuga]

Reminder: I changed oil & all filters yesterday.

As luck would have it we had a fairly cool morning, about 79 degrees. So I had to wait to test my gen cooling system until this afternoon when the temp was around 86 degrees.

I removed the radiator cap, started the generator, turned on both ACs, both stove burners, the dryer, and unplugged the shorepower cord. I was drawing 50 amps on each leg! 100 amps total - the gen was loaded up! I watched the water in the radiator and very soon it started to move around back and forth - NOT circulating - just moving around and bubbling a little.

Next, I felt the top hose close to the thermostat; it was hot and I touched it every few minutes to see if it would get burning hot. I couldn't tell much difference thru the entire test; it seemed about the same temp everytime I touched it. So since it didn't get too hot to touch, I assume my thermostat is bad and I will change it. Newell service told me not the run the gen when the slide drawer was open for a long time, so I retracted it while I was running the test. I left the radiator cap loose on top of the radiator neck.

After 45 minutes of running with a load the operating temp was 190 degrees
After 1 hr it was 200 degrees
After 1 hr 15 minutes it held at 200 degrees. If the ambient temp was around 93 like it was this past weekend @ LSU the operating temp would have been around 210 or 220 like it was in Baton Rouge.

At this point I removed all loads and just let the generator run drawing 0 amps. 45 minutes later it was running at 180. I think we can clearly assume the higher the ambient temp the higher the operating temp (unless you have a super human generator).

Sooooo.... it looks to me that my thermostat is bad and is not opening. I changed it about 2 years ago and I will change it again. I have seen water flowing in a radiator (cap off) before and mine was NOT flowing. There was a good bit of wind from the gen blower and at first I thought the wind was moving the water. It looks to me like the water pump is working at about 50% capacity; if that's possible. Before I change the water pump I am going to have the radiator cleaned and inspected and I am going to change the hoses (keeping the old ones as spares).

The slow movement of the water could be caused by 2 things: a clogged radiator or a marginal water pump. Since it is less expensive to clean the radiator I will start with that.

I would be interested to hear others thoughts.

[prairieschooner]

Tuga,
I am sure that you know this but.......I always check my Thermostats by looking to see if it was Closed. Then I would Heat some Water to about the Rating of the Thermostat. I would then submerge the Thermostat and it should Open. Then I would remove it and see it Close.
Simple but effective test. I do this to all new Thermostats prior to installation.

[HoosierDaddy]

Steve you just reminded me of something my dad would do....
Place a deep pan of water on the stove with a thermometer in it.
Manually force the thermostat open just far enough to stick a heavy string through about 1 inch or so then allow the thermostat to close thus pinching the string.
suspend the thermostat in the water by the string and turn on the heat.
When the thermostat opens it drops to the bottom of the pan. At that time check the water temp!!!

[tuga]

Steve & Hoosier,

Great idea! I checked the thermostat last night in a pot of boiling water and it opened. When I turned off the fire and added cold water it closed; so it works.

I will try your 180 degree temperature method this morning.

I removed the radiator last night and will bring it to a radiator shop to be tested and cleaned as needed this morning.

Thanks,

[prairieschooner]

It was my Grandfather that taught me this and yes I forgot the string.
Sometimes simple is best!

[tuga]

I got a call from the radiator shop this afternoon; they found 2 leaks in the radiator. One leak was in the top tank (fixed it by soldering) and the other one was where a tube met the bottom (fixed it by soldering). Next they are going to remove the top tank and "rod" the tubes out. This will break up and flush thru all of the rust, gook, etc. that builds up inside the core. The mechanic told me after he rods it, it will be as good as new.

I think my problem is fixed; but we'll see.

John Clark w/Newell had a few suggestions: check the generator door for air leaks (this is the part of the fiberglass front cap that has NEWELL written on it). If the gasket on this door is leaking it will cause the gen to run hot. Next, check the belts for tightness. And lastly, verify the accuracy of the VDO gauges by using a non contact infared thermometer.

John also suggested that I change the fuel solenoid on the gen for my "bogging down" problem. It is an intermittent problem (is there any other kind?) He said that the fuel solenoids get weak over time. I ordered one today from Chuck Clark in parts.

It sure is nice to have a great company like Newell Coach and the members of this forum to fall back on. Ron Skeen gave me a call today and shared his thoughts. Thanks Ron.

I love my Newell!

[tuga]

I checked the generator door on the slide out. It was leaking air profusely! That has been the cause of my overheating problems all along (for 5 years). It will be a simple fix once I get the proper gasket material from Newell. It takes a special gasket; one that has slit in it so it can fit onto a metal rib that is at the bottom of the generator compartment.

If your generator runs hot during high temps but runs cool when outside temp is under 80 - I'll bet you 8 to 1 thru a nickel in a doughnut that you need a new generator door gasket.

Since we have cool weather now, I won't need the new gasket until next summer. But, I have it on my list next time I go to Newell.

[encantotom]

i ran the genny all day today while driving. it got up to low 190's when all air conditioners were running. it was pretty warm out today.

tom

[tuga]

Tom,

Would you do me a favor? Please check your generator slide door gasket for air leaks. Just run your hand around the outer perimeter of the generator slide door gasket and feel for leaks. I would just like to know how many Newells are leaking air at this point.

Forrest is going to check his and let me know.

If anyone else out there would like to participate we could see if this is a common problem.

I'll post the results to this post by editing it each time someone reports.

1. Tuga - leaks air
2. Tom - very little leaking
3. Forrest - very little leaking
4. Steve B. - very little leaking
5. Clarke - no leaks
6. Dean - no leaks

[RussWhite]

Hi Tuga,

I have been following this thread with interest. I am still a little too banged up to do much outside. Could you please explain in some more details how the air flow works on our vintage generators? I only have a very basic understanding that the air is pulled in through a grill work on the curb side front bay and into a squirrel cage blower. From there I am just not sure how it gets to the radiator on the generator or where exactly the gasket is you are talking about. A picture might be nice with a written explanation. As soon as I can and understand what you want me to check I will add my input to your poll. Thanks, Russ

[rheavn]

Tuga,
I have followed your thread & will be interested in the results of the radiator rodding. I have never seen my genset temperature guage over 180 no matter how hot or number of a/cs running, but you're a little hotter & humid down south.
I performed an air leak test with the following results: I thought I could feel a little air leaking at the front cover on the upper sides & top, but very little. I used a paper towel around the areas I could feel it & it didn't move. I used a length of toilet paper & I could now see a very small amount of pulsating air leakage on the top & upper sides. No air was leaking on the lower sides. The side vents for the squirrel cage had a tremendous movement in of air.

Hope this info is helpful................

[folivier]

Just checked mine. A little amount of leaking at the top corners and bottom corners. Looking at the gasket it looks in good shape, but it is one continuous piece. It turns 90 degrees at the top corners. I may add a small piece at the corners to see if that stops the leaking but I haven't had any problems with overheating.

[tuga]

Hi Tuga,

I have been following this thread with interest. I am still a little too banged up to do much outside. Could you please explain in some more details how the air flow works on our vintage generators? I only have a very basic understanding that the air is pulled in through a grill work on the curb side front bay and into a squirrel cage blower. From there I am just not sure how it gets to the radiator on the generator or where exactly the gasket is you are talking about. A picture might be nice with a written explanation. As soon as I can and understand what you want me to check I will add my input to your poll. Thanks, Russ

Russ,

It is a very simple concept: the blower sucks air in to the squirrell cage and pushes it into the generator compartment. The cool air pushes the hot air out of the compartment via a duct directly under the generator. If air escapes out thru the front of the generator compartment door the generator will run hot because all of the hot air is not being exhausted out of the bottom.

The gasket is visible when you open the generator door (slide out). It is glued to the outer perimeter of the opening and the generator door mashes up against it when the generator door is closed.

While your generator is running, pass your hand around the edge of the fiberglass door (has Newell written on it) and determine if you feel any air escaping. When I walk past mine it will blow my hair (the little I have left). That's how badly my gasket needs changing!

Sorry I don't have any pictures.

[RussWhite]

Tuga,
Thanks - Is all this air that goes in somehow forced through the radiator before it all ( hopefully ) leaves through the duct work at the bottom?

[tuga]

Tuga,
Thanks - Is all this air that goes in somehow forced through the radiator before it all ( hopefully ) leaves through the duct work at the bottom?

Russ,

I am not really qualified to answer that, but here goes. Yes, I would assume that the hot water in the engine travels into the radiator when the thermostat opens and allows it to enter. Then, the cool air is blown around the radiator tubes and directed across them by the fins. This air cools the tubes and the water inside of them. The heat that is given off is removed by the movement of air and is exhaused out of the bottom of the compartment.

I never completely understood why Newell doesn't put a fan in front of the radiator to draw the air across the fins. I'm sure they have a good reason though.

[folivier]

Looks like the generator compartment is pressurized by the squirrel cage blower. The only outlet is through the radiator then ducted (in front of) out through the bottom. I was surprised also when I first looked at my genny and there was no radiator fan.

[HoosierDaddy]

I did a little research before modifying the cooling system on my '78 Newell. The issue is noise suppression. The more turns the cooling air makes going in and coming out the less engine noise that is able to escape the "box".
The squirrel cage fan helps in three respects. It allows for a lot more air movement with less noise than a typical engine fan, eliminates a direct path through to the box, and by "packing cool air into the box some of the surface heat of the engine is exhausted throught the radiator and out the bottom.
I was able to dramatically reduce the gen noise outside of my '78 by adding metal-work around the perimeter of the radiator to seal it to the front of the box, then I closed off the traditional grill and modified the front cover so that it drew air in from below the front bumper instead of directly in the front.

[chockwald]

I have a fan on mine that pulls air through the radiator, and yes, it is loud if you are outside near the front of the coach. Inside it is not that noticeable. Driving, of course, you don't hear it at all. The compartment surrounding the genset is not sealed, and is open on the bottom, front and rear...top and sides have insulation.

[encantotom]

i did check mine and i have a small air leak on the bottom 4-6 inchs on both verticle sides. not enough to matter i dont believe but i will play with it some when i get home.

tom

[RussWhite]

I checked mine also and have a very small leak at the top two corners. Otherwise it is tight all other places. The amount of air exhausted in the proper location is very impressive. Thanks for making me aware of this potential problem. Russ