Hi, On some web sites backpack blowers had the nickname "Bad Boy" due to their noise. I actually have a Redmax 8001. I am not a pro gardener but have alot of trees and leaves to shift come autumn, actualy right about now. Yes it does make alot of noise, but it is OK if you wear some ear protection. I use those small yellow disposable sponge things AND a set of STHIL ear muffs. I also use the same ear protection when I am running my Honda HRC216 mower too. I find it alot less tiring when all the noise is cut out. As for power, I think you can never have enough. I think the Redmax 8001 is about the most powerful there is. If you have any more power the weight will sort of get to you. The only down side I see on the Redmax is the weight. It sort of gets to me after about 45 mins of use. Then again I am a wimp.... The Redmax has so far been very reliable and I am on my third season with it. All the best, Mike.

When the effluent rises it has some velocity, and hence momentum. When it enters the hood it has a tendency to "reflect" and curl downward and potentially escape. If the hood is deep enough (top to bottom) and the hood fan flow is high enough (cfm) the curling effluent will remain captured and will be exhausted. The barrel design in the picture looks to me (without examining one) like it has adequate depth. W.r.t. ya think's question a few messages up: First I would say that the change from vertical to horizontal should be as large a radius curve as you can fit to minimize pressure loss (as well as noise). The effluent momentum (which is a vector) is being changed in direction. This is akin to stopping it and starting it up again. If it can slide along a curve, the momentum loss is significantly less. There is one commercial ducting source I came across once that uses 90-degree transitions, but embeds a curved shape within the duct to improve the flow. I find it hard to answer the question of what questions to ask. Usually, the answers aren't available. Ideally, one would want to know the fan curve (flow vs. static pressure) and try to estimate all the pressure losses (including the pressure one might pull the house down to with or without make-up air) to see what the real maximum flow rate will be. This can then be compared against estimates of effluent generation rate calculated from the reference below. The power used might be adjusted to represent your cooking style, as rarely would one have all burners on maximum and cooking at the highest pan temperature. One thing is certain, flow rate in the hood has to at least equal the flow rate from all the active burners and pans, and arguably should be higher due to imperfect effluent collection. Implied above is that the hood manufacturer can supply pressure loss of the filters vs. flow rate, as well as that of the hood transitions. Getting that data, even if it were ever measured, would be unlikely, me thinks. I suggest that various hoods be "audited" in showrooms to gain a feel for their noisiness versus their designs. The reference worth reading, even if one doesn't intend to use it for calculations, is "Thermal plumes of kitchen appliances: part 2 cooking mode," by Risto, Hannu, and Pekka. (I've found it on-line whenever I've looked for it. Part 1 is also interesting.) If you do use it for calculations, please note the following apparent errors in their Equation 1: The constant should be 0.05 not 5. The units of phi should be kW, not W. (these corrections make their tables consistent with the equation) You will need a scientific calculator or counterpart software to do the exponents (unless you are very old school and know how to do logarithms). You will also need to convert BTU to kW and cubic meters per second to cubic feet per minute. This is left as an exercise for the student. [insert sociopathic laugh here] kas

IÂll share what I am doing about makeup air. I need to qualify this with the fact that we have not closed the house yet so performance is still to be determined. I researched commercial installations. If you are obsessive I recommend http://energy.ca.gov/reports/2003-06-13_500-03-034F.PDF. A recommended setup is to replace about 80% of the exhaust air with makeup air at the cooktop. Pulling the rest of the makeup air from the room seems to improve capture. We have a sealed combustion oil fired boiler and no fireplace so I am not too worried a slight negative pressure. Even with new construction there is still some infiltration. For example, the baths and laundry are vented to outside. Another thing to consider is the temperature of the makeup air. In cold climates it may be desirable to temper it. I am going to try it with no tempering, but I have made prevision to add a duct heater if it is required. My plan was to pull the makeup air from the outside; however, my builder suggested we pull it from the unheated attic. He thinks that increasing the air exchanges in that space would be a good thing, IÂm not sure. There are lots of ways to deliver the makeup air. One of the better ones is to deliver the air under the cooktop. My cooktop will be mounted in such a way to create a 6" x 40" channel under it. The end of channel is covered with a decorative grate. The air flows under and to some extent through the cook top, around the front, then up and out the hood. This pattern creates very effective containment of the plume.

I took the valve cover off, again, and checked the tightness on the rocker arm stud. It was tight with no indication that it had ever come loose or backed out. I think it was just the locking screw for the rocker arm nut had not been tightened properly in the past allowing the nut to loosen and the lash to get "way huge". As for Walt's comment. You may be right. When I was first starting to trouble-shoot my problem I noted a ~5/8" OD rubber hose that comes from the engine having come loose from the ~1/2" fitting it connects to on the carb. I attached it and secured it with a hose clamp. I would guess that this is something like a PCV valve line on an auto engine. Anyway, connecting it did nothing to solve my problem. I have not had the engine running w/o the cover/air filter on since the valve lash was adjusted, so I don't know if the gases pulsing out the air intake still happens, but I have had the air cleaners off of plenty of carb-equipped cars in my 64 years and I have NEVER seen air pulsing out the carb with the engine running like I saw with this tractor engine. In any case, with the piston moving up and down inside the engine, you will have alternating positive and negative pressure and so no net air movement inside (other than from rings blow-by...and this thing does not have enough hours for bad rings...I hope). Anyway, she runs smooth and quiet now. I down-loaded the Briggs owners manual and parts manual for this series engine. If you have a service manual, I would love to have a copy. Will contact you at your e-mail. Thanks! One caveat is that the cheap Chinese tach/hour meter I use says that it idles at 4200 rpm now (meter set to one revolution per spark pulse due to the magneto ignition on this thing firing each revolution). I know it is supposed to be governed to 3400 rpm and 4200 would be too high. Don't quite trust the meter, though, as the idle just sounds "right" and not too fast. Ordered another $10 tach/hour meter and if that one says 4200 rpm idle, too, I may adjust the governor. Thanks to all for suggestions and comments!