House Calls with the RV Doctor
By Gary Bunzer
March 2007
Dear RV Doctor:
We just purchased an RV with an Onan Marquis generator. We went to change the oil for the first time, and after warming up the generator, we could not get the oil to drain any faster than a drop at a time. We opened up the drain valve and unscrewed the filler cap. Other than that, we’re not sure what to do.
Kandie Nield
Hagerstown, Maryland
RV Doctor: Kandie, I hate to be the one to ask this, but are you absolutely sure the crankcase is not simply empty or very low on oil now? I’d suggest pouring in about half a quart, leaving the drain valve open, and watching to see whether the new oil immediately drains. If it does so, that generator was quite low on oil when you went to change it. However, if the new oil does not drain normally, then you apparently have a blockage inside the crankcase or in the drain valve itself. You can try using a flashlight and mirror to see whether any blockage is visible. If not, it may necessitate having the generator removed from the coach and the oil pan taken off for a thorough cleaning. But first pour a quart of cleaning solvent or very light oil into the crankcase and stir it around with a screwdriver, reaching through the dipstick/cap cover. Perhaps that will dislodge or dilute any sludge blocking the drain opening. You may even try to snake a flexible wire up through the drain valve in case the blockage is only located there. Be sure to flush it thoroughly and to fully drain everything in the crankcase before adding fresh oil. Don’t forget to replace the oil filter as well.
Loose Lags
Dear RV Doctor:
The mounting holes at the awning rail on my motorhome are stripped. I don’t know how the roof is constructed behind this rail. Do you recommend just installing larger lag bolts, or do you have a better idea? Right now, 1/4-inch-by-3-inch lag bolts are installed.
Sal Lugo
Wurtsboro, New York
RV Doctor: Sal, most motorhomes are reinforced in those areas where awnings are typically installed. A wooden support usually is built into the wall (and near the floor line) to accept the awning mounting screws. If your lags are simply stripped, try removing the upper brackets and plugging the existing holes with a 1/4-inch wooden dowel. Apply some carpenter’s glue to the dowel before you hammer it in. Be sure it fits snugly. If it appears to be loose, wedge some shims in alongside the dowel. Trim off any portion of the dowel that sticks out. Once the glue sets, simply reinstall the same lag screws after drilling 1/8-inch pilot holes. Seal the open holes with silicone before installing the awning bracket.
If the internal framing consists of aluminum or steel studs instead of wood supports, you may have success simply by going to a larger 5/16-inch lag screw, as you’ve suggested. You’ll have to drill the holes in the mounting assemblies larger to accommodate a larger lag.
If the sidewall/roof area is not beefed up or properly supported internally, it may be necessary to “bolt through” the entire sidewall. This can be accomplished by fabricating a 6-inch-square aluminum plate with holes drilled to match the spacing of the mounting holes in the upper awning bracket. The plate should be about 3/16-inch-thick. Ideally, it can be hidden inside a cabinet. Instead of lag screws, it will be necessary to use 1/4-inch bolts, nuts, and washers “” long enough to pass through the awning bracket, the sidewall, and the interior plate. Not the most aesthetic fix, but effective. Hope this helps!
Limited Longevity
Dear RV Doctor:
We are shopping for a used motorhome and would love to have some guidelines for how long major components should reasonably be expected to last. Recognizing that there will always be wide variations because of usage levels, maintenance done, and hours spent in campgrounds with poor voltage, etc., how long might refrigerators, air conditioners, generators, awnings, water heaters, water pumps, etc. last? We’re looking at a 7-year-old Damon with only 23,000 miles on the chassis and 107 hours on the generator. But we wonder how much we might have to spend over the next couple of years. Should the roof air conditioner likely be good for a few more years, or should we just replace it now even though it works? Ditto for the other bigger-ticket items.
Keith Bryan
Grant, Florida
RV Doctor: Boy, Keith, that’s like asking how long is a piece of rope! But at least you did phrase your question in context. I’m of the opinion that when cared for properly, RV components can last a long, long time. Regular preventive maintenance practices can really prolong the useful lifespan of just about everything on the coach. How long? Like you stated, it depends on the treatment it has received during its life.
I am personally wary of LP-gas-burning appliances approaching 8 or 9 years of age. Some components do wear out over time. One hundred hours on the generator is not outlandish; however, I’ve always said non-use is worse than abuse in many cases.
With any used RV, I would heartily recommend that a predelivery inspection (PDI) be performed on all the components in and on the motorhome prior to signing on the bottom line. This procedure will reveal compelling issues that can then become a bargaining chip for negotiating the final price. I’m also of the opinion that just about anything can be repaired or, at worst, replaced if need be. But I would never replace a major component until absolutely necessary. A 7-year-old unit is not that old, especially with such low mileage. So I would think your chances are good that most everything will be in working condition as it stands. But again, a thorough PDI will reveal any shortcomings with the LP appliances and the major systems. Consider it cheap insurance to PDI the rig prior to taking ownership.