I just bought a Coachman Class C RV that's based on a 1986 E series van, which is my first Ford. I'm assuming it's on an E-350, as it has a dually rear axle. My main questions are about the engine, which I was told it's a 460 and it supposedly has a bad ignition module. The module is a finned aluminum box, that I was told is a common issue with that year. I haven't taken possession of the RV. I haven't looked close at it or started to work on it. The first thing I plan to do is a compression test and replace the spark plugs. I prefer regular copper NGK plugs if they're available. Has anybody had bad experiences with them in old big blocks like the 460? What's the typical real world compression numbers for a low mileage carb RV engine in decent condition? Any tips for diagnosing the ignition system? I plan to start with the basics like grounds and power and do a full tune up. If I keep this RV long term I plan to convert it to Diesel, likely a 7.3 IDI. If the engine is in good condition is it worth anything? Any chance it's got a 4 bolt main block?

 

How many miles on the clock?

If you’ve tested/test for spark (?) (none present or weak), the ignition module can be easily removed and tested prior to a replacement. Most quality parts houses have the test equipment for ignition modules.. Pickup coil inside the dist can be a culprit as well, but generally if a no spark condition the module is the more common suspect and should be proved out.
I’d make an attempt to start it and take it for a test drive to evaluate its condition if it’s sat for any real length of time.

A diesel conversion would be a huge task, fairly expensive, more so without a donor truck or if the sourced IDI donor engine is in need of a refresh. You’d need much more than just the engine, trans, and fab/source to make any swap possible.
Many years ago we used to install Perkins and Detroit diesels in later 70’s F Series trucks, well before Ford had any offerings. Even with more simple or pre electronic engine management /fuel controls, a sizable job.. State Emissions May come into play If applicable.

460 is a good platform, although not bashful about consuming fuel, a decent power/torque contender to push the house down the road.. A 7.3 IDI turbo/non turbo was a little shy on output, and other than MPG may not yield much better performance if any..

 

43,000

I haven't done any work yet. The seller played around with it, gave up and sold it cheap. It's been sitting for a few years at least, so it could be as simple as a wire chewed up by mice/rats. Is there an aftermarket or upgraded factory module that's better? If it has failed at 43,000, that's pretty sad.

I'm a Diesel guy and don't believe that our normal junk US spec "gasoline" (really gasohol) is an appropriate fuel for a vehicle that may sit unused for long periods. Non ethanol fuel is hard to find and costs more then Diesel, even with the cost of adding the sulfur back into the Diesel is factored in. I'm down for engine swaps and plan to buy a donor truck or van. I may even swap both engines and resell the donor vehicle. I'm also down for rebearing and reringing engines. I'd only consider the IDI as I don't believe in computer controlled Diesels. FL is an emissions free state.

I will probably look for a used Banks kit, although I don't plan on cruising on the freeway at 80 or pulling long uphill grades in the fast lane.

 

Hello Andrew
They built the 460 from 1968 through most of the 90's
both carb and FI versions.
compression test is a good idea. change all belts hoses HT wires.
put the original Ford plugs in the damn thing. if all is well, you could put a Holley sniper EFI on it.
I don't know what state you live or what you can do with a car, but you could put a Mallory HIE distributor in it
if possible.
6000 Lb and you worry about fuel !
Best