Put your concerns to rest. So long as you have sufficient space for the filter to mount up without chafing or rubbing any part of the machine (that could damage the filter body) you will be OK. As pointed out above, having an "anti-drain back" valve (check valve) incorporated into the filter is important. I personally think it is also important that the filter media be of a "waterproof" material (and Wix, to name one, uses waterproof media). ALL internal combustion engines produce water as a byproduct of the combustion process. During "cold start up", a significant volume of this water gets past the piston rings and into the crankcase where it becomes entrained into the lube oil. Usually this is a "temporary" condition as the water is later evaporated back out of the oil as the temperature of the engine and lube oil rises higher than the point where liquid water can exist. This phenomenon does not normally have any effect on filter media that is NOT WATERPROOF, especially in air cooled engines (because of their characteristic higher operating temps), as the water in the oil never remains there long enough to soften or weaken the filter media to the point of "matting over". Cold engines that are started up and shut back down without the engine ever reaching operating temperature are the ones most likely to suffer from water induced filter degradation (or failure). Liquid cooled engines that have a defective head gasket can have water contaminated oil before the complete failure of the gasket makes the defect apparent "otherwise". Liquid cooled engines that are operated with the thermostat removed (or stuck open) will also suffer more from this type of degradation because the engine "runs too cold" for longer time before heating up enough to evaporate the water from the oil. "Matting" of the filter media occurs if the (non waterproof) fibers of the filter lose some of their "structural strength" due to becoming pliable when they absorb water. As the fibers settle (pack down) on top of one another, or swell up in diameter, the filtration rating will increase (catch smaller debris) temporarily. It is "temporary" because once it gets "matted", it can no longer flow the same volume of fluid it was intended to. As the matting effect increase, the filter bypass valve will unseat, allowing some unfiltered oil to "bypass" the filter media altogether. A matted filter might bypass oil during a cold start up due the the inability of the media to flow the viscous, cold oil, and then resume filtering the oil once the oil warms and "thins out". Matting can also lead to tearing or rupturing of the filter media, which then allows some of the trapped debris, and sometimes, bits of the filter media, to be transported out of the filter and into the very engine components that are are supposed to be protected by the filter. Oil filter manufacturers (that use non-waterproof media in their oil filters) hide behind the disclaimer "it's an oil filter, not a water filter" to defend their choice of materials, and (hopefully) for most folks, the fine detail of "waterproof versus non waterproof" media will never become an issue.

Sorry if my last post sounded abrubt (not intended), re-read and I should have worded it differently. I do appriciate the help. About the possibly overfilling it. That would seem to be good news considering the alternative. I've changed the oil before and it never did this...but maybe. I'll go back out and add some oil well below full and see what happens and just keep adding little by little. If in fact I overfilled it is there a mess inside the enginge that could harm the motor when I finally get around to starting it? You understand that when the oil started leaking I hadn't ran the engine at all yet, right? In other words would it be leaking w/out ever starting up if overfilled? Going now to re-read oil filling instructions.

The subject of grease collection in ventilation hoods is a complex one and subject to significant research and measurement. My generalization of some reports I've found is that neither screens or baffles collect more than about 30% of the effluent, and that which is collected comprises the larger droplet sizes. The hope is that the smaller sizes stay in the air stream until exhausted. There are hoods that use baffles backed by other media that collect more of the the total particle distribution. There are ventilation systems that just suck all the stuff into the ceiling and use strong UV to inert it before exhausting it. So baffles are not the only game in town, but are considered adequate for many applications so long as the duct velocity is kept in the 1000 - 2000 feet per minute range. kas

The heatpump has 02 date on it, so it's 8yr old or less. when I flip the switch on and off the fan in heatpump doesn't always work. I tried like 6 times and it turned on by itself only once or twice. Also, I noticed that the circuit breaker (inside the house) makes a noise every time the fan is trying to start. Is that normal for circuit breaker to make this noise? The lights in the house flicker when it makes this noise, but once I start it up with the stick everything is back to normal. I had an oil service rep over at my place and he said it's normal for lights to flicker, but at that time I didn't know that the fan doesn't work. now I wonder if it really is normal. Another strange thing - it 70 inside and 70 outside, but when I tried to bring the room temperature to 68 the air coming out from the ducts wasn't cold enough, not nearly as cold as it was in the summer.I ran AC (with fan running) for about 45 min, but it's not the ice cold air that I was getting in the summer . Thanks