RV Repair – Tips for Inexpensive RV Repairs (Part 3) RV Batteries Explained!

There are different battery types for very different purposes. In this article we will be referring to the “chassis” battery and the “coach” battery.

A “chassis” battery starts the engine and runs the automotive systems in either the motor home or the tow vehicle. A “coach” battery powers the lights, furnace, water pump and other 12 volt devices in the coach.

Engine Starting battery – this type of battery is constructed to supply a high amount of current in a short amount of time, as when starting a cold engine, and then it is recharged immediately by the engine alternator. The internal plates are thin to allow more contact area with the acid solution. This allows a great amount of chemical reaction to take place in a short period of time. The starting battery does it’s job very well but will perform poorly as a coach battery.

Marine Battery – this type of battery is constructed in a similar way as the starting battery but the internal plates have more support built in to withstand the pounding of a boat going over rough seas. This battery is required to provide high current to start the boat engine, so it is essentially a beefed up starting battery.

Deep cycle/RV battery – this type of battery is built to supply relatively smaller amounts of current for relatively long periods of time without being recharged immediately. The internal plates are thick and robust to supply this continuing current but the power is distributed over a longer time span. A deep cycle battery will require a longer recharge time at a lower current level to be fully and safely recharged.

Multiple RV Batteries

Connecting Multiple RV Batteries

When installing more than one battery for use with the 12 volt RV system, it is recommended to purchase the batteries at the same time. The batteries should be matched with regard to capacity, brand, and age. This will give you the best possible life from your RV battery bank.

RV Battery Voltages

RV Batteries are constructed to supply 12 volts or 6 volts (for the purpose of this article).

In most cases two six volt batteries will have about 20% more capacity than two similar sized 12 volt batteries. This is due to the larger plates that are built into a six volt battery.

RV Battery Circuits

Two 12 volt batteries are connected in a parallel configuration with the two positive terminals connected together and to the positive trailer lead. The negative terminals are connected together with the trailer negative lead.

Two six volt batteries need to be connected in a series circuit in order to get the 12 volt needed to run the coach system. In this case the trailer positive lead is connected to the positive terminal of the first battery. The negative terminal of that battery is connected to the positive terminal of the second battery. Finally, the negative terminal of the second battery is connected to the trailer negative lead. The size of the jumper wire should match or exceed the size of the trailer leads.

RV Battery Polarity

It should be noted that the positive lead from the trailer is normally the black colored wire(s) while the negative lead is the white colored wire(s). This is sometimes confusing, as most automotive applications use red as the positive and black as the negative. Polarity is very important to the electronics and the various motors in the RV and must not be reversed.

Note: battery terminals (or posts) are marked with a plus sign for the positive terminal and a minus sign for the negative terminal.

To make it even more confusing, makers of after market items, such as solar panels will have the red wire as positive and black as the negative.

Before disconnecting your RV battery for any reason, it is suggested that you tape the wires together near the terminal that they are attached to and then mark them with respect to what terminal they go to. This will avoid confusion and reversed leads when re-connecting the terminals.

Foundation Repairs – How to Repair Pier and Beam Foundation Problems

The procedure to repair a pier and beam foundation properly requires a thorough inspection of the crawl space. The crawl space is the area beneath the floor that has pier supports, girders, sill plates and joists that need to be visually inspected for termite damage, dry rot, mold and proper engineering.

A structural engineer should be involved in the inspection and repair analysis to insure the proper repair is outlined correctly. Expansive clay soils can move the independent areas of the foundation and crawlspace causing distortion in the structure and leaving signs of foundation movement in different degrees. Plumbing leaks and poor drainage are contributing factors that can influence the clay soils causing them to swell and compromise the supporting elements of the structure.

The repair method is dictated by the findings in the inspection that the engineer outlines in his report. A repair must follow the engineers outline to insure longtime performance of the end result. Using sub grade materials can result in a failed longtime repair causing costly future expenses to maintain the foundation.

There are different types of pier and beam foundation construction depending on the interior and exterior loads the structure is carrying. The size of the girders or beams along with the size of the joists dictate the design layout of the pier and beam structure. The larger the joists the further the girder supports are allowed to be spaced. The larger and deeper the interior girder supports or piers the further the allowed space between piers.

Ventilation is critical underneath the floor to reduce the effects of moisture in the wood elements and mold. An engineer should include in his report if the ventilation needs to be increased and how many, type, size and locations of vents to promote proper ventilation. Improper ventilation can result in reduced longevity of the wood elements resulting in future avoidable expense.

Drainage correction in areas of ponding water within 10 feet of the structure should be addressed by the engineer. Poor drainage can cause the crawlspace area to accumulate standing water especially if the ground surface elevation underneath the floor is lower than the exterior ground surface elevation, A french drain is usually recommended to address drainage issues around the foundation where your trying to lower the water table.

Pier and Beam foundation are classified as deep foundations. They have builders piers beneath their exterior grade beam. The pre-construction piers are installed before the exterior footing of the grade beam is poured giving the exterior beam extra support and a deeper foundation. Diameter and depths of the piers vary depending on the loads and geographical locations. Most builders piers I have run into on pier foundations are attached to the grade beam footing with rebar even though Engineers recommend to not attach the footing to the piers.

When built in areas with expansive clay soils void boxes are implemented under the footing to help allow the clay soils to swell without lifting the structure. Soil tests are done to determine the amount of swell in the clay soils called PVR ( Potential for Vertical Rise). In Irving TX there are areas that have as much as 13 inches of swell in the soil.

The problems with repairing a pier and beam that foundation companies run into are usually with older structures with brittle concrete footings. If a repair is done with push piers using the weight of the structure the grade beam will not be able to take the stress required to install the piling without damaging the footing. Concrete pressed pilings are problematic when installing because pier and beams are light structures and proper depth is hard to achieve. I have run into the same problem installing steel piers either the structure is to light or the beam gets damaged from the flex of the beam during the driving process.

A drill pier or helical pier works for installing without compromising the integrity of the concrete in that they are not a push pier installation but are limited to the depth they can achieve but are still a better alternative. The main focus should be on proper maintenance regimens after the repair to help keep the moisture content more stable after the repair is done.

Re-shimming the crawlspace should be done with steel shims as they will not compress or rot. Solid concrete blocks should be used in lieu of cinder blocks. Engineers do not like to see concrete cylinders unless they are poured in place band are reinforced with rebar.

Another type of pier and beam structure is called a block and base foundation. A lot of homes that were built in the 1800’s and early 1900’s were of this type of construction with bois d’ arc piers. I still work on these type of foundations today. They are well ventilated most of the time because they have a skirting instead of a concrete perimeter beam. If installing new pads it is recommended they either be poured in place or the foundation of the pads need to be buried a minimum of 6″ beneath the soils surface to prevent the pads from tilting over time.

The History of Automotive Repairs – Why We Need Trained Technicians in the Collision Repair Industry

Vehicle History Overview

  • They don’t make them like they used to.

The First Cars

  • The first motor cars were nothing more than a buggy and engine (Generally repaired by blacksmiths and carpenters. These cars were very expensive, which only the wealthy could afford)
  • Model T was the first car mass production on an assembly line in 1908 (Ford’s Vision was to produce an affordable car the average person could purchase)
  • Model T’s came in black only to keep the costs down. (The price came down once the assembly line was streamlined, but in 1908, the cost for a Model T started at $825. By 1913 the cost of the car reduced to $550)

Cars in the 1960s

Cars were made the same basic way up through the 60s

  • Body Over Frame
  • Rear Wheel Drive (Same concept, but the cars were very big, bulky, and heavy)

Except people in the 60s wanted SPEED! They achieved this with Big Block Motors, which created a lot of Horsepower. (The Birth of Hotrods, Rat Fink, Flames, and Pin Striping).

Cars in the 1970s

  • The government place strict fuel economy and emissions control laws
  • Customers demanded cars with increased fuel economy
  • New laws and customer demands started the automotive explosion of engineering ideas and changes in the automotive industry

Changes to comply with Demands and Laws

  • Smaller bodied cars and smaller engines
  • Aerodynamics (Increase Fuel Mileage)
  • Lighter cars by using different materials and designs
  • More work-hardened areas created during formation of panel (Body Lines)
  • Safety

Construction of Interstate Highways + Higher Speed Limits + More High Performance Cars = Accidents and More

Deaths from Auto Accidents

Federal Laws were passed to regulate safety. These laws included:

  • Installation of seatbelts
  • Safety glass windshields
  • Head restraints
  • In 1979, the first driver side airbag was introduced
  • Airbags are mandatory in motor cars produced after 1990
  • Unibody Torque Boxes: Allow controlled twisting and crushing
  • Crush Zones: Made to collapse during collision (To act as an absorber, absorbing the impact)

Modern Day Cars

  • Carbon Fiber Parts
  • Aluminum Parts
  • More Plastic Parts
  • High Strength Steel
  • Boron Steel
  • Unibody Construction
  • Space Frame Construction
  • Computer
  • Hybrid Cars

Now they even have cars that will tell you when you’re lost, where to turn, Parallel Park for you.

Conclusion

While the modern day cars appear to be made cheap and unsafe, they are actually designed to crush or collapse, while transferring the energy around the stronger passenger compartment to protect the passengers from injury.

There is considerably more damage to modern day cars during a collision than the older vehicles, which gives the perception that “they don’t make them like they used to”. However, in reality the cars are taking the impact instead of the passengers.

The lesson was designed to give you a little history, but to also emphasize that just a hammer, dolly and a few wrenches are not going to repair today’s cars. We need highly trained collision repair and automotive technicians to repair today’s vehicles.