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Discussion Starter · #1 ·
After hunting at the junkyards for months, I have finally found a 1982 Maxima Diesel in a nearby U-Pull it junk yard.

I decided to take today off from work, because I have been putting in a lot of hours, and my wife and 15 year old son are very demanding of my time. I had just one important thing going on at work, so I took th day off. I got to the junkyard at about 9:30 (it's about an hour and a half from my house). There really weren't too many Z's or interesting cars there today. As I got to the last row of foreign cars THERE is was. A Maxima with the Diesel badge on the side. I was in the back. Do I dare look to see if the engine is still in it. O.K., let's see. THERE IT IS. Is has the funny shaped valve cover with DIESEL on it, and the odd shape head with the head bolts on the outside.

Oh, brother!! Now, I have my work cut out for me. And, I was going to go into the office for a while to do that one thing I have to do. Oh well, this is more important. I have my cell phone. They can always reach me if they have to.

Rubber gloves on, let's rock and roll. Working for about an hour, RING, RING, RING. Cell phone. Biggest client, Needs me to call her back and spend an hour going over some reports. Can't stop now. I agree to call her back in an hour. Still not done pulling engine. What to do? So I go to a local Office Depot, where you can receive and send faxes. My secretary sends me a faxed copy of the report. I call the client. We go over everything. She is happy. I fax changes of the report back to my secretary and go back to the junk yard. WORKING, WORKING, WORKING. Almost 5:00 P.M. Engine finally out. I wheel it to the front office of the junkyard. I can buy the whole engine for $99 dollars, plus core charge. I ask if I can buy just the crank. YES!! Much cheaper (I didn't ask). BUUUUTTT!! IT's 5:00 o'clock and the junkyard closes at 5:00. What to do? They say If I come back tommorrow when they open at 9:00, the engine will still be there and I can pull the crank. I can't wait.
 

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here's my funfilled adventure!!!

Sounds like a good deal coop.I
loved the part about puttin'
your most important client off
to work on your Z quest for more
displacement!!! HAHAHA Glad
you got your priorities
straight!! I also found a 82
maxima diesel in the want
ads. The guy said it ran rough
and it did. Anyway I got the
whole car for $200 and proceeded
on my way home. I looked like
james bond goin' down the
highway with smokescreen in full
force..HAHA Anyway it was
runnin rough and started slowing
down on the interstate and I
barely made it to the off ramp.
After exiting, it stopped
completely in the middle of
traffic;NO Problem i'll just
push it right?WRONG All four
brakes had locked up.So there I
am in the middle of the road
just a 1/4 mile from the Highway
patrol with a car with no
taillights, Busted
windshield,three bald
tires,outdated inspection
sticker,a tag off another car
and some drug stickers on the
back saying Altered State of
Mind Talk about sweatin'
bullets!!! Anyway the good Lord
must have been lookin' out for
me, cause 2 minutes later a tow
truck came by and rescued me
from some hefty fines!!!
Although the tow did cost me
$50, mainly due to having to put
the locked up wheels on a dolly.

I thought I would get
lucky and only have a bad diesel
injector pump....turned out the
rod had broken due to the idiot
not changing the oil. The
resultant goop had blocked the
main oil supply to the #2 rod
which caused it to sieze and
then snap off.Needless to
say,the surface of the crank rod
journal was less than perfect,
although the crank rang true
when tapped with a hammer, so it
was'nt cracked at least!! I was
able to sand and smooth out the
rough spots on the crank, but
the thought of investing $3000
or more on a proper 3.1L engine
based around this crank just
didn't seem like a great
idea.SSoooooo whats a guy to
do....I know, build a JUNKYARD
DOG 2.9L!! I had a bottom end of
a 280 engine with a two piece
crankshaft(one too many wide
open throttle speed shifts)hehe
which had some good stock
pistons and a good bore, so with
a few unorthodox mods, I hope to
have this thing runnin' by march
I've shaved the piston tops
.015 and balanced the pistons
and rods so that they all weigh
exactly 1445 grams, so this
should help with the less than
ideal rod ratio and positive
deck clearance. Since the head
was shaved .070 a few years back
I will be using two head gaskets
with a felpro shim in between to
give me approx.10.7:1compression
ratio. Anyway ,if I get this
thing runnin' strong my total
cost will only be about $300!!!
But if not and it blows up the
first run, I'll just chalk it up
to the school of hard
Knocks...real hard knocks!! hehe
Later,norm
 

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Think twice about that Diesel Crankshaft!

You realize that crankshaft will need a lot of work done to it before you can use it right? The diesel cranks are very heavy, if you get it try weighing it and compare it to a normal Z crankshaft. The cranks are intentionally heavy in a diesel engine, they used compression in order to ignite the mixture. They need to have a lot of momentum in order to do this efficiently, Thus the extra weight. The diesel engines have a low redline because of this as well(check it out for yourself). It can be done, just do it right or you'll end up breaking stuff. Just thought I'd give you a heads up, I did the same thing you are doing and found out later this info and decided not to do it because it would cost hundreds of dollars in labor to get the crank lightened, turned, and balanced.
Good luck,
Tim Deesen
 

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Re: Think twice about that Diesel Crankshaft!

I've heard arguments both ways in the lazy rev vs torque arguments. I have a diesel crank and when I weighed it compared to a stock l28 one the difference was less than two pounds. Do I have a modified crank already, or is the weight argument just a rumor? I seriously doubt my crank has been lightened, it looks totally stock and came out of a stock diesel maxima. Maybe its more a factor of where the weight is located. Someday I'll build it and see how it performs. It's not like it's a major stroke increase. Only adds about 100cc's to a stock bore. The 3.1 and 3.2 numbers come from a combined stroke increase with a near maximum overebore. Plus most conversions also use the heavy cast truck pistons which might contribute to the bad rep. Who knows?
greg
71 240z

> You realize that crankshaft will need a lot
> of work done to it before you can use it
> right? The diesel cranks are very heavy, if
> you get it try weighing it and compare it to
> a normal Z crankshaft. The cranks are
> intentionally heavy in a diesel engine, they
> used compression in order to ignite the
> mixture. They need to have a lot of momentum
> in order to do this efficiently, Thus the
> extra weight. The diesel engines have a low
> redline because of this as well(check it out
> for yourself). It can be done, just do it
> right or you'll end up breaking stuff. Just
> thought I'd give you a heads up, I did the
> same thing you are doing and found out later
> this info and decided not to do it because
> it would cost hundreds of dollars in labor
> to get the crank lightened, turned, and
> balanced.
> Good luck,
> Tim Deesen
 

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Tim:Someone misinformed you!

Tim ,I just weighed the crank and it is only a little over 1 pound heavier than my 280 crank(weighed both pieces) arghhh.Anyway I think what someone was trying to tell you about was the heavier diesel rods which you dont use anyway,and the much heavier flywheel(37 lbs)as compared to 280 flywheel of only 23 lbs.I will be using my old 19 lb 71 240 flywheel.Thanks for your input though,had I not weighed it myself, I would have been worried if someone had then told me what they told you. Later, norm
 

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Re: It does not weight more

> Tim ,I just weighed the crank and it is only
> a little over 1 pound heavier than my 280
> crank(weighed both pieces) arghhh.Anyway I
> think what someone was trying to tell you
> about was the heavier diesel rods which you
> dont use anyway,and the much heavier
> flywheel(37 lbs)as compared to 280 flywheel
> of only 23 lbs.I will be using my old 19 lb
> 71 240 flywheel.Thanks for your input
> though,had I not weighed it myself, I would
> have been worried if someone had then told
> me what they told you. Later, norm

Yes, tim, I concur with Norm. After my extensive 3.1 buildup, I know the weights are within the normal tolerance of such. The slight weight increase is because the throw is just that much longer, thus making it slightly more material. The limiting factor in a diesel is the compression ratio,(which is often up around 25:1). They were not designed for high rpms.
I can post more about the 3.1 later, but I have to run out for the day. I have a lot to say about the lazy reving. The biggest factor in that is balancing and the wrong cam for a 3.1. By nature, they tend to peak hp a little lower than a similar 2.8, but it is more, and has a much wider torque curve. With a lightweight flywheel, a great balance,(ie a race shop, who knows L6 motors), and good parts, it willingly revs to over 7k. I usually run it up to about 6800, and shift there. My motor is a little different than other 3.1's, and that is a factor. But I really have to go. If you want more info, I can post it. Check out my 3.1 page if you want to know more.
-Bob Hanvey
 

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Discussion Starter · #7 ·
Went Back Today, Pulled the Crank $17!!!!

> After hunting at the junkyards for months, I
> have finally found a 1982 Maxima Diesel in a
> nearby U-Pull it junk yard.

> I decided to take today off from work,
> because I have been putting in a lot of
> hours, and my wife and 15 year old son are
> very demanding of my time. I had just one
> important thing going on at work, so I took
> th day off. I got to the junkyard at about
> 9:30 (it's about an hour and a half from my
> house). There really weren't too many Z's or
> interesting cars there today. As I got to
> the last row of foreign cars THERE is was. A
> Maxima with the Diesel badge on the side. I
> was in the back. Do I dare look to see if
> the engine is still in it. O.K., let's see.
> THERE IT IS. Is has the funny shaped valve
> cover with DIESEL on it, and the odd shape
> head with the head bolts on the outside.

> Oh, brother!! Now, I have my work cut out
> for me. And, I was going to go into the
> office for a while to do that one thing I
> have to do. Oh well, this is more important.
> I have my cell phone. They can always reach
> me if they have to.

> Rubber gloves on, let's rock and roll.
> Working for about an hour, RING, RING, RING.
> Cell phone. Biggest client, Needs me to call
> her back and spend an hour going over some
> reports. Can't stop now. I agree to call her
> back in an hour. Still not done pulling
> engine. What to do? So I go to a local
> Office Depot, where you can receive and send
> faxes. My secretary sends me a faxed copy of
> the report. I call the client. We go over
> everything. She is happy. I fax changes of
> the report back to my secretary and go back
> to the junk yard. WORKING, WORKING, WORKING.
> Almost 5:00 P.M. Engine finally out. I wheel
> it to the front office of the junkyard. I
> can buy the whole engine for $99 dollars,
> plus core charge. I ask if I can buy just
> the crank. YES!! Much cheaper (I didn't
> ask). BUUUUTTT!! IT's 5:00 o'clock and the
> junkyard closes at 5:00. What to do? They
> say If I come back tommorrow when they open
> at 9:00, the engine will still be there and
> I can pull the crank. I can't wait.
Well,,, I went back today, pulled the crank, and it was only $17!!! Boy, did I get dirty; those diesels are nasty, sooty, pieces of crap. I felt like I wrestled an anaconda and lost by the time I was done. It pulling it wasn't Bad enough, my wife was pissed becaue I didn't get home until 3:00 p.m. Oh well, at least I have my priorities straight.
 

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Hey, ya want to double your money?!! HAHAHA

What a deal!!! I loved the stuff about the pissed off wife.Sounds familiar,hahaha. Wish I lived near your local junkyard,if only they knew a Z freak would have easily given them $200 for that crank.Good luck with your stroker project. Later,norm
 

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fix to your crank problem

I once bought a 240 that didn't run after having it towed home, I decided to try to start it and it cranked right up. about 20 minutes into its first drive it lost power and immediately siezed. It had a fresh rebuild, and I bought it from the guys mother who had no idea what was wrong with it. When I pulled the engine apart, it turned out the guy put both bearings in the #5 cylinder in backwards, and it got no oil at all to that crank journal. The con rod froze to the crank journal.

Anyway, I took the crank to a machine shop and for 150 they added metal to it and ground it back down and polished it back to specs. You'd be surprised what can be fixed.

FWIW, Mike Golding
 

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Re: What year did those come in????

And can that be used in place of the 83 turbo unit in my car. Or is it only interchangeable with earlier blocks/trans/flywheels? I want to rebuild a motor to replace my original motor which has 211K. Something is gonna break sooner or later.
 

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Re: Need some crank advice

I have a crank that I was told would fit an L-28 motor. It was included with a dissambled motor that was included with a car that I purchased. Attempting to assemble the engine the crank seemed to fit length-wise. When I turned the crank the journals were too long and were hitting the inside of the block. Fortunately, I had another crank and was able to successfully assemble the motor. The crank has E30 stamped on it and again it seems to be the correct length but it definitely will not work in a 78 280Z motor. Any suggestions or advice? It is in exceptional shape, has been polished and is available. Any help would be appreciated.
 
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