Bummer, now we are having cooling issues on our genset. `

[John316]

Folks,

We are heading west on I80, right now.

Our generator is a EPS 20KW quiet box model. It is situated to where it exhausts the hot air from the rad, down through the floor. The shroud that puts the air through the floor, is the shroud that EPS has designed. They said that they engineered it exactly for that purpose (they had VERY specific instructions on opening sizes, etc).

The only way that we were able to fit the generator in, was with the rad towards the front of the bus. The generator takes the air for cooling in from right under the engine (you catching my drift?) So the hot rad air exhausts right infront of the air intake (meaning the hole cut in the floor right under the engine).

So the challenge is to get the hot air out, and get the cooler air into the engine. I think if we get that figured out, we will be made in the shade. We tried putting a mudflap, that I cut down, between the rad output, and the air "intake." That didn't help at all, and just made things worse (maybe because it was pushing air up working against the rad fan?). I had the mudflap at a big agle to try to push the air out to the side, but it was a nogo.

Ideas? Suggestions? Comments?

Also that was the only way we could mount the genset with the rad infront. We worked and worked, to try to get things different, but it didn't go. Also, we don't have anywhere where we can remote mount the rad.

Thanks a lot.

God bless,

John

[steve wardwell]

is there any way to pick up air from the other side of the bus? say your gens to port. how bout a grill in the floor to starb with a  blower pulling air from there to feed the gen on the port...(box it all in and have a false floor on the starb side and open to port) you could put your flap between the holes and you would'nt pull air sideways.......In our bus we pull air from the starb  floor with a blower  and push air out on the port floor with the  rad.fan in a box tight to the floor.....2 years ago when we were running warm and days were 95-100 deg  we increased the in opening and solved our heat issues....s.....

[bevans6]

I completely don't understand where your gen set is, or where the air is feed from/to, sorry.

Brian

[steve wardwell]

he has his hot air exhaust in front of his air intake so the heat is looping and overheating .I think he has to offset to stop the looping

[bevans6]

You shouldn't pull air in from the floor, since it's about the strongest low pressure area around the bus when it is moving.  Changing the air intake to anywhere else will help that.  It's possible the airflow through the rad is just not sufficient.  But so hard to say without seeing the install., so just guesses on my part.

Brian

[robertglines1]

heat rises...grill to outside from compartment? possible to be closed off during non heat stress times...

[John316]

Thanks for the replies, folks. Keep em coming. So far so good.

I will try to get pictures of the setup tomorrow.

Just to answer a couple of quick questions. The rad has enough of an outlet, because EPS sized it. EPS was the one that engineered the shroud, and it is fancy. So per Kubota and EPS specs, we have enough air. We do just fine sitting still (we can put a load on it, and stay under 200). It is driving down the road that we have the issues.

Thanks again for the suggestions. It gives me something to chew on for awhile.

God bless,

John

[TomC]

Since the hot air coming off the radiator is under pressure from the radiator fan, use some sheet metal to make a duct that moves the hot air to one side to the point that it won't be recirculated back into the genset.  Good Luck, TomC

[buswarrior]

All your cooling "engineering" is being ruined by hurtling down the highway.

It sounds like the install has game ending flaws.

The hot output being ahead of the intake, under coach.... you already have found out what that does. Whatever you try to install to divert this mess is only going to get ripped off or feed some large amount of dirt into the gen rad, making more trouble.

Kick yourself, hard, and then do it again, because you really didn't kick yourself hard enough the first time...

Ok, now that I've done the Lord's work,  is it possible to spin the thing around, front to back, so the hot goes out the back and the cold comes in the front?

Take some pictures and get 'em on here so we can get a better idea of some potential solutions.

There's enough coolant in the generator, isn't there?

happy coaching!
buswarrior

[John316]

Gents,

Thank you all for your comments and suggestions. We actually think we have it solved. We called EPS, and explained the situation to them. The gent that we worked with said we shouldn't be having that issue. He said they have had their gensets in EVERY imaginable configuration, with no issues.

As I mentioned below, we had installed some mudflaps to try to help cool the genset. The problem was, that we installed a mudflap aft of the radiator output. So driving down the road, air was being rammed up into the rad (backwards) and was prohibiting the hot air from exiting like it should. The other flap was at an angle to try to scoop air over into the intake (are you lost yet? ). After we did those two mudflaps, the cooling was worse then ever. We removed them and were back where we started.

Anyways, the gent at EPS told us to try installing the flap IN FRONT of the rad. (This way it would be "blocking" the air the as you drive down the road.). He also said to install the other flap BEHIND the generator. This created a low pressure area under the genset.

So far it seems to cool just great. This goes right along with what Clifford was telling Wal todo with his genset.

I will try to get pics up someday.

God bless,

John

[Ericbsc]

I have an onan quiet diesel with the same set-up. I have had a few issues with cooling on the road also. Mine pulls air un fore and exits aft. Is it possible to turn your unit around so it is pullin air in in front and exits back. I know everybody suggests that the air not come in from the bottom, but that is the way these units are designed to operate. I tried the scoop thing and it didnot help. I added a 350 cfm in the generator compartment itself and routed the injection air inlet outside. That seemed to word. See where the unit pulls air into the filter. Mine was inside the unit. It was pulling hot air into the unit. I moves the intake and added an outside intake.

[John316]

Eric,

Thanks for the comments. I like the idea of moving the air intake. Good one.

We really wanted to install it to where it was exhausting hot air out the back, and the intake was on the front, but we had a problem with that. All of the routine maintenance items are on that side. If we flipped it, then we wouldn't be able to change the oil filter, fuel filter....etc. We thought hard how we could change the install, but it was a nogo.

Anyways, it looks like EPS gent helped us get the issue fixed. Time will tell.

Thanks for your help.

God bless,

John

[Hcklbery]

My genset and air circulation solution was to get a Honda 2000 and then a blower fan from Walmart (not an oscillating fan) and place both in the compartment where the big AC evaporator radiator thingamabob use to be (after I put an aluminum plate down for a floor) and situated the blower about 6" behind the gen where it exhausts (doesn't expel hot enough air to cause concern for the blower) and not only does the blower suck in the exhaust but in expelling it out of the compartment it also keeps the air circulating. I've been in some hot summer days and no problems.
btw that blower sucks air in from the side and expels it out of a directional controllable front louver.

[Lin]

This post certainly emphasizes the importance of correctly understanding aerodynamics in relation to cooling issues.  It is really amazing what a simple mudflap can do.