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GMC Vandura Fuel Delivery System Questions

I have a 1986 GMC Vandura 2500 Tra-Tech Conversion Van (3 speed auto). It was given to me because the Rochester Q-jet fuel inlet threads were torn up. Not just cross threaded were they, but much of the metal is gone. It appears the "fix" (a self tapping filter housing) will hold for the moment, but I don't know for how long. I have to drive it at least 15 miles to keep the van. Afterwards I can take an indefinate amount of time to properly repair the beast. I intend on towing in the nearby mountains the heaviest trailer it can safely haul (I have that figured at about 3500 with my setup, and it has done so throughout it's life since new to my Grandpa, now I'm 30 and married with children so the van would be a plus for family vacations!!!).

Considering the carburetor will at least have to have a new body and be rebuilt (the cheap way out), I was wondering how easily I could upgrade to throttle body fuel injection. I have no desire to pay thousands for a kit (note: kids), but I have read that GM vehicles can often be upgraded by simply using a donor car. This van was offered with TBI, and I'd be willing to scrounge those parts, but am I likely to run into any major differences other than changing out parts? I am very familiar with how mechanical fuel systems work, but I need work on my electronic injection knowlege (ironically I'm a computer major, but not in automotive electronics). I have a 99 Jeep Wrangler that I'm willing to take apart to study (I will need to put it back together, so I cannot intentionally sabatoge it for study, but disassembly is okay). It has TBI. I'm open to the critical teachings of the experienced at hand :)

It should be noted that the van appears to have left the factory as an

85 GMC Vandura Cargo Van, and returned as an 86 GMC Vandura Conversion Van, so I'll need to know if there were any major differences in the two years.
Reply to
teachknowlegy
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The reason for the difference in the year is because the original van was sold as a base cargo unit, it then went to the conversion shop and was completed. Because the conversion added seats and other items to the van it also changed it's vehicular type. That means that is has to be reinspected and they issue a different title.

For the conversion you won't need a lot of parts. You will need the computer and wiring harness for a TBI unit. You will need the intake and TBI unit itself. The fuel pump you have may work depending on what pressure it operates at (test it to see what it has now). You will be changing the distributer. The handiest way is to grab the book for the vehicle and match the items.

Reply to
Steve W.

Thanks, that definitely cleared up some other issues pertaining to what I can legally do with the vehicle here. Aparrently as a passenger van the rules about moving about the van during trips changes a bit in this state (VA) vs. a cargo van that has been converted by a DIY. Did you know that the state police here told me they consider the converted vans just like RV's (living quarters) and won't bug you about seat belts and open containers if there are no other disturbances? I'll never let anyone drink in my van while in motion, but I thought the comment was interesting. I grew up with the idea being in the van children are free to swap seats or lie down in bed, but in the other cars you are belted driveway to driveway using this same van.

Thanks here, too. I have decided to stick with a rebuilt used replacement carb for the moment, but will be considering TBI as a future upgrade plan. I have learned a great deal about this van, and it turns out that I have plenty of power in theory with the carb. If I experience fuel delivery problems in the mountains I will reconsider this again. I have also thought about "greener" alternatives even, ultimately converting to propane or natural gas as a fuel. I would think the carburetor would need to go in that case.

Another note is that GM has declared that van capable of towing 8800 lbs (per several dealer's notes) minus the converted weight difference, and DMV claims VA allows 10,000. I would be scared to place that kind of load behind it. If the van can tow a lot more than

3500, I'd probably be willing to put a 5-6000 lb. travel trailer behind it. Any ideas?
Reply to
teachknowlegy

Mine is rated to tow 5,000 without any problem. Keep in mind that the rating assumes that the body and supports are in good shape. Rust on the GM van bodies (especially on the rocker panels) through the 1995 model year also compromises the towing rating. That is because they are a unibody vehicle and don't have a true frame under them.

I would go by what GM says for tow rating, they built the vehicle. Also check the brake ratings to see what you actually have. Also look at the rear axle rating.

Reply to
Steve W.

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