1977Monashee wrote:
Hey Guys and Girls!! I am really new to Rving, as I just bought my first RV last year!!
I bought a 1977 Monashee, on a dodge MB300 chasis. Class C. It has a V8 318, automatic transmission. I bought it in saskatchewan, and drove down to nashville and then back to ontario which is where I live. It has 104 669 kms on it right now. It ran great and only had minor problems. The spedometer sometimes "doesn't catch" once im at 60mph, it floats back and forth between 50-70 mph and makes a loud, annoying noise..... The rear main seal also has a slow leak which I think Im going to replace soon. I have done a little research and have never seen another Monashee model? The camper was made in Penticton BC, and the frame made at the warren factory.
Have any of you ever heard of the Monashee Model??? Any thoughts or comments are much appreciated!!
Regards,
1977Monashee
Pictures please.
Three components in the speedometer system: drive gear, cable, and instrument. The drive gear in the transmission is plastic but is probably okay. The cable may be worn, dry, or gummed up and should be cleaned and greased before thinking about replacement.
The instrument in the dash is a mechanical revolution counter that may be gummed up. They sometimes develop a "dead spot" at the vehicle speed most commonly driven. You could try cleaning and lubricating it. It's a non-electrical clockwork device so it's somewhat delicate.
The same mechanism was used on all Mopar vehicles for decades. The differences between various model is in the bezel and faceplate. (You can convert it from KPH to MPH and vice versa by just replacing the faceplate.) Chrysler parts departments may still have new ones available, as well as parts stores. You might also be able to find NOS speedometers on eBay. Otherwise, hunt the junkyards and craigslist for Dodge, Plymouth, Chrysler, Imperial, and Fargo vehicles being parted out.
I actually have five or six speedometers buried somewhere in my storage sheds. I know one has a damaged odometer due to being melted by sun heat. I'm holding on the rest to use the one in best shape in my current project. I probably could spare one but cannot attest to the condition of any of them. (i.e., it'd be best for you to find one locally.)
You probably have a 318-3. The -3 was an industrial engine, which had stronger components in the basic 273/318/340 block. (The 360 has larger mains so used a different casting and oil pan.) The most important part is a forged, rather than cast, crankshaft. Crankshafts gain strength with use and forged crankshafts start out stronger than cast or billet. Simply put, a used forge crankshaft is the best thing you can lay your hands on, which is why racers desire them and have made them hard to find.
The best way to determine if you have a -3 is look for "318-3" stamped into the front of the block on one bank just below the head. It may also be listed on a data plate under the hood or encoded into the VIN, assuming the engine wasn't replaced at some point. (It's not uncommon to find a -3 was replaced with an ordinary 318, although this is fairly uncommon in motorhomes.)
If you have the engine rebuilt, make sure the rebuilder keeps the same crankshaft during the rebuild.
Make sure the oil leak is from the engine and not the transmission. There is a dye you can put in the engine oil to find the source of the leak, using a special light and glasses. The kits sold in parts stores are usually used to detect coolant leaks, with different dyes sold separately for oil leaks.
The most common source of oil usage on 273/318/340/360 engines is disintegrated valve stem seals. Fortunately, these can be replaced without pulling the heads and should be tried before pulling the heads. (If you rebuild the heads, you should also re-ring the cylinders to avoid transferring the problem from the valves to the rings.)
Replacing the valve stem seals involve pulling the valve covers and using air pressure through a spark plug fitting to hold the valves in place.
The techniques mention in the two previous paragraph are described in detail in various books and websites so I won't go into detail here.
Advancing the timing a few degrees on your engine will improve your gas mileage, as long as it doesn't cause the engine to ping. Likewise, slowing to 50 or 55 mph will boost your mileage. (Both lessons learned on my '77 B-200 318, although I tended to ignore the speed recommendation.)
Ignore mileage for determining oil change frequency. Change the oil every three months when in use and just before putting your motorhome in storage. Unburned hydrocarbons collect in the oil and turn to acid when exposed to moisture. On highway travel, the engine warms up long enough to evaporate the hydrocarbons and moisture and expel them via the PCV system. Short (in-town) trips allow them to build up and, subsequently, corrode engine parts when not in use.
Elsewhere in this thread are lots of info on keeping your motorhome running well.
