Hello glorious folk of this forum, first post here, getting straight to business:

There is a 1975 E250 with the 460ci 385 V8 in it and a camper conversion up top from that era as well. 132K miles, fair state. Attached is a photo.

My questions:

1. I am having it inspected on June 2 of 2016 at a place that was recommended for their ability to assess frames and frame issues. What should I look for and what questions should I ask about the frame itself and things like rust or damage or excessive wear? Looking underneath it, I can see the differential has surface rust on it and things do look a bit corroded, but I can't tell what's surface and what's not. Will a reputable shop tell me as much?

2. I don't care about the motor as my intention is to pull it out, clean it up, and sell it, to fund a diesel conversion, most likely the Powerstroke 7.3L. What should I watch out for when it comes to assessing the appropriateness of this rig for such a dramatic transfusion?

3. Can anyone tell me about doing suspension conversions on this thing? I would REALLY like to have an independent multi-link front and rear, but I don't know how feasible that is on this kind of vehicle. I understand it's more expensive, I'm just interested in knowing when it becomes radically impractical to attempt.

4. Anything else I should know before I take the plunge?

Thanks for reading, hope I don't sound like too much of a douche! It really seems like an awesome van...

 

Welcome to the site

Looks like a clean van. You live in the rust belt?
A reputable shop should certainly be able to tell surface rust from rust from that would/could affect the frame and body 'structurally'.

Back in the 70's we used to do Perkins and Detroit diesel conversions into mid 70's F series trucks, Allison auto's and manual gear boxes. A diesel conversion is a large task, more so if your planning on a electronic controlled power plant like a later SD PS. A manually injected, no modules, would be less of a build, less money, but also, generally less performance. Suspension, trans, cooling, fueling, driveline changes all come into play. As does 'room' for the power plant swap. What generally saves time and money is if you can find a donor for the M/Y you plan on converting from/to.

Dramatic,, is a good word to describe the task at hand, and generally a good knowledge of fabricating/ welding helps as well. Not to mention a good shop to work in since down time, part sourcing, fab work, heavy lifting and staging for fit all will take time. More so going into a 70's rig.

kinda like the old Harley question,,, how much power and speed can I get?? Depends on how much money you want to spend, and how much time you want to invest.

Back in the day when we used to convert the 70's F's over to diesel, we used to have to hand fabricate the engine adapter plates to bell housing/ trans, mounting points,/ hardware, and just about everything else the transplant diesel needed to work, drink, and breath.

 

Hey Hayapower, thanks for responding, sorry for the late reply (notifications...)!

I live in northern California, north Bay Area. According to climate data for my area:

"The relative humidity typically ranges from 40% (comfortable) to 97% (very humid) over the course of the year, rarely dropping below 18% (dry) and reaching as high as 100% (very humid). The air is driest around October 3, at which time the relative humidity drops below 53% (mildly humid) three days out of four; it is most humid around November 13, exceeding 96% (very humid) three days out of four." ¯\_(ツ)_/¯

All good points on the diesel conversion, my thoughts are basically gutting what-all's in there (that 385 seems like it'd be a fun project to learn to rebuild a motor on, low stakes for me since I'm not interested in using it at the moment, so I can take my time on it and such), and the donor vehicle makes a lot of sense. I'm fluctuating between a Cummins 4BT or ISB, and a Powerstroke at the moment, more time to put a finer point on either argument later though. The goal is efficiency and power, so going the hard road with electronic injection control will probably be the way I go really.

I know how to weld most processes (gad/stick/MIG/TIG) and cut with either oxy-acetylene or plasma, but I haven't done that stuff in a long time and never did it professionally. I can operate most heavier tools but don't have specific knowledge or training on machining, so I'd be outsourcing what's too technically complex for me. Probably gonna be a lot... My main concerns are doing anything on a 40-year-old frame that would weaken the whole thing structurally--cutting this off or welding this on, and somehow introducing heat-stress or other weaknesses in the whole thing, so I'd like to figure out what's the best way to learn about where the stress points are, what could use reinforcing, what should not be touched and what's generally safe to modify.

Another question: how in the hell can I get registration information from like Carfax or something on a VIN number this old? Standard attempts to decode this VIN have been futile so far, I'm just trying to find out if it was registered to someone who lived on the coast with the salt spray air or up in Tahoe where they salt the roads... Doesn't seem like it but I'm not really a good judge of that stuff as I said.

Thanks for reading!

 

I grew up for the most part in the North Bay, Novato for 35 years, Petaluma and Rohnert Park for a few more. I' m about an hour and a half from the Oregon border now.

4BT may be a bit under powered for that weight rig. Problem during conversions is usually clearances. The Cummins is gonna be long and tall. Going into a van body may be more of a challenge.

Frame cutting, reinforcements, sectioning, boxing, double plating, are done all time in conversions, stretch limos etc. Dending on what/where the alterations are made would depend on the now needed support and reinforcement level.

You might be able to go to DMV and have them look at the last owner/s on record. Small fee/ doc for them to check.
I would think if it were in a corrosive environment long enough to weaken the frame, it would have shown up by now in the body panels as well. Surface rust on the frame, probably a given. Flaky, blistering frame sections or collection points, would be another story. That said, to make room, and carry the diesels extra bulk, you'll need to add/remove some iron..

 

Nice, I'm in Napa Valley myself! My intention is actually to drive it up and stay in the Portland area for about a week at a time or so!

And crap.... Flaking you say? I did see some of that on a bit of the rear undercarriage and differential... I guess I'll wait to see what the shop says on Thursday, but now I'm a bit apprehensive...

My gearhead friend was relating to me about his turbocharged 4BT that was good for something like 400hp/lb.-ft or the like, so it sounds like there's more tweaking to be done on those, but strangely they seem to weigh more than the powestrokes... Dunno, still figuring that out, thanks for the input!