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Diesel swap 97 d21
Posted: Wed Jan 13, 2016 10:19 pm
I have a 97 nissan d21 pickup extended cab 5 speed 4x4 2.4 L 4 cylinder. I am wondering what would be the best options for a diesel engine. I would like to have more power and be able to comfortably drive 70 mph on the highway, if possible. I am really looking for millage and more power. I would also like something relatively simple, if possible. I am okay changing motor mounts and things of that nature but i am no wiz when it comes to electrical so any advice will be greatly appreciated.
Re: Diesel swap 97 d21
Posted: Sat Jan 16, 2016 6:35 am
Welcome to the forum.
A couple of thoughts on your "project".
First off, there is no real "drop in " option for any of the diesels to your truck.
The oil pan will be one of your biggest hurdles to overcome, although there are a couple of guys on here that have made their own pans and have had success with that, it was however ( as I recall ) a bit of a "process" to get it done and not leak.
As for Power.
Your 4 cyl gas engine makes much more power than one of these little diesel guys, unless of course you turbo charge it and that is a possibility as well, as again, some guys on here have done this with good success. It was not cheap to do and some fabrication was involved to get it done.
Then you have the marriage to the transmission to deal with as your bell housing will have to be changed over to accommodate the diesel. Not impossible, but again, a bit of a process, and that's not including the transfer case hook up.
Electrical will have to be done as well. There will have to be a vacuum pump of some sort installed in order to operate your brakes, HVAC, etc. If you can find a diesel that still has the operating alternator with the vacuum pump on the back of it that will work, but not certain about the plug configuration and hooking all that up. Can be done of course but will require some research. There are electric type vacuum pumps available and that would allow you to use your existing alternator once you fabricate a mount for it to fit the diesel. Hopefully the V belt pulley will be compatible with the diesel. Power steering mounting will also have to be dealt with.
Wiring and timer for the glow plugs, fuel shut off, etc. as well.
Then there is the fuel supply, and not certain how or what your existing fuel tank is made from but that may have to be changed because of the corrosive nature of diesel fuel.
There is a thread on this forum someplace that deals with that issue. Not an immediate issue, but long term can cause some problems.
You will also have to plumb in a return line to the tank. If the present tank has an "in tank" fuel pump that would have to be removed as it is not made to deal with diesel fuel, and would create too much pressure to the diesel fuel pump and could damage the lift pump. Diesel fuel filter assembly would have to be affixed at some point as well.
Not certain what side your exhaust presently runs along, but with the diesel it will run on the drivers side.
The above are a few things that just quickly came to mind. There will be other issues as well I am sure.
I have a 1987 D21 2wd with an SD25 in it. It does OK with mileage as I usually achieve around 37mpg Imp
(7.6L/100km) in the summer months and 32mpg Imp (9/100km) winter.
Not all that great, but not horrible either.
(If your looking for vw tdi mileage/torque it wont happen with this engine)
This engine in this application desperately needs about 5lb of boost. I am living at around 1200m (4000 ft) and it has a tough time pulling some of the hills around these parts at even 80 kph, the hill out of town I am down to 60kph in 3rd gear. I'm not certain where you live or what your elevation is but, 70 mph (112 kph), in my opinion, would be ambitious and a strain on this engine because of the sustained higher RPM and, you cant gear it any taller without losing HP/Tq.
Kind of a catch 22.
I still have the 14 inch wheels on the truck to maintain some of my mechanical advantage.
So in conclusion..........
My personal opinion would be to look at converting your truck to the V6 option that was available then. Still would have some major changes to do under the hood with mounts, exhaust, wiring, electrical, transmission etc, but, still less than swapping to a diesel. All the V6 conversion pieces required would be available from either Nissan or from a junk yard. Perhaps the lesser load on the V6 from the 4 would translate to a bit better mileage, or perhaps the same with more HP.
I wont even go into the diesel engine spare parts thing.
Hope this helps.
You can search this site for what some of the members have done to put these engines into different 4X4 applications and read the processes and creativity they went through to achieve it.
Again, not impossible, but not simply purchasing parts and bolting on either.
Good luck and keep us posted on your progress or your decision.