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New to me sd22 powered 720, need some guidance.


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I picked up a '81 720 KC with a SD22 in it.


I've replaced the mechanical fuel pump and cleaned out the fuel lines.


Fuel injector pump solenoid unit has been replaced with a choke cable connected to the spring linkage the solenoid arm used to be connected to.


It starts and idles great with a small amount of white smoke on first start of the day.


It's anemic as all hell in first and reverse gears, I know these things only had 60hp when new, but it almost dies when letting the clutch out in first or reverse. I basically have to rev a bit and dump the clutch to get going from a stop reliabily.


Anyone have any ideas? Thanks!

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Yea, you have to give it some pedal to get it going,you don't have to dump the clutch, you just let it out slowly, you will get used to it, so is your daily driver an automatic?


These small SD22 engines are not very powerful, they have the torque of an L20b but they are severely lacking in HP, both my Datsun diesel trucks have SD25 engines, they are definitely better than the SD22, but still lacking in HP, so after driving my 521 kingcab for several years I finally turbocharged it successfully, here are a couple threads about the journey I took getting to where I am today, all the victories and defeats, it has been a long journey.








I helped my friend turbocharge his SD22, I was not impressed with the result, but it was only here one day, given time I suspect I could have figured out what the issue was and found more power, but he doesn't live near me.

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I had a 1982 Datsun 720 SD22 diesel powered truck, my only complaint was the lack of power on the freeway, 70mph was close to being floored, I sold that truck as soon as I got the 521 kingcab with the SD25 diesel engine going, the SD22 powered truck would be great for people that like driving 55mph and it gets really good mileage, 35mpg is common on the freeway, and I got 25mpg in the city no matter what, but the freeway I only got 27/28mpg as I wanted to go the speed limit(70mph), now with the turbocharger I get 30mpg going 75mph, if I could drive 55mph I would likely get close to 40mpg.

You will get used to letting out the clutch while giving it some pedal even though it seems like a granny gear, it is not a granny gear, it's about the same gear as a gasser except the gas engine will rev up to 4500rpms easy, out diesel engines don't like it over 3000 rpm in in any gear except 5th, it sounds over revved at 2600rpms or higher in 1st thru 4th gears.

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This is the Isspro tach I have on ebay, I am not saying buy this one, but I am very happy with mine, but I don't know if this one comes with everything you need, none of them on ebay say if they come with the kit that has the glue on magnets/glue/sensor/mounts, mine came complete, now it appears they are sold separately.



If you go to this link below and scroll down it says frequently bought together.


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No just a standard bed, just ment it being a truck vs a car with good gas mileage. My last truck was a v6 '99 Ford ranger, fun truck; 18mpg highway...


Also wewy those are expensive for some tiny rare earth magnets and a Reed switch! That's like $5 in parts!

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I don't know what they are made of, I just know I am happiest with that Isspro tach, mine was around $150.00 complete when I bought it directly from Isspro(across the river from me). 

I also have a Tiny Tach, but my 2nd one has never worked properly and they didn't want to fix it, so I don't suggest them anymore, and when the internal battery goes dead you need a new one, I was unhappy that when I let off the pedal it switched to total hours instead of dropping in RPM like my first one worked


Them SD22 engines got really good mileage under 60mph, and it wasn't so bad on level ground, but when it came to going up a hill it drove me crazy.

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