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1981 300GD
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Discussion Starter #1
Have the engine installed & have done some moderate driving. Overall impressions:

An update for the curious.

After putting in the turbodiesel from an '82 sedan...

1) significantly less low end torque, but much better drivability at 7000-8000 feet above sea level where we live.

2) off-road performance somewhat less, but acceptable for what I do. The variability in the power caused by the turbo is manageable. A little more care is needed in driving, and the days of being able to crawl at a constant speed with constant level of pressure on the throttle are over. Much more active management of the throttle, but it's not really distracting.

3) some further adjustments necessary. I'm not convinced I'm getting everything out of this engine that I should be, so she's going in to the mechanic for a checkup to verify that valves, injectors, filters etc are all in good shape.

4)The 4-speed manual isn't as well suited to the TD's power curve. Needs either closer gears with a lower 1st gear for off-road use or an auto trans that would get the turbo spooled up faster. (Dreaming military 5-speed here.)

5) Bottom line: if I lived at sea level and did substantial off road driving and not much city driving or city driving with hills, I'd stick with the 300D. At altitude or if I did a lot of normal city driving in a hilly part of the country, I'd definitely accept the tradeoff and do the TD conversion again.
 

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230 G BGS 300G TDI
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That bears no resembalance to how I would describe driving my conversion.
I think you may need to.
A. Do as you say and give it a good service
B. Tweek the inj pump, Have it turned up a bit by a competent mechanic
C. Fit ann itercooler
D. Have me ship over the mil box I have lying in the shop.
 

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1981 300GD
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71 Posts
Discussion Starter #3
Update after adjusting valves, replacing all the filters, cleaning the injectors, and replacing the injector pump...

What a difference a little TLC makes. I can actually ACCELERATE going uphill (3-4% grade) in 4th gear.

Going up I-70 out of Denver, the G now outruns my 1995 Isuzu Trooper (barely)

Still think I've lost a little torque at the very bottom (minor, not tremendously noticeable), and I would like the 4 speed's gear ratios to be a tad closer, but that's probably more due to my own driving style and personal preferences. The turbo surge off-road remains manageable - the boost doesn't kick you in the pants, so it's not like you rocket ahead into the next tree. There's plenty of warning, and time to reduce throttle.

Now I think I may need an overdrive....

As an additional bonus, since I haven't dialed the ALDA back down, when people tailgate me going up I-70, I can dust them pretty badly with black smoke. So far noone has insisted on staying too close.

While the normally aspirated diesel would have been fine at low elevations in flat country, I definitely would do this conversion again even at twice the price. Another upside - my wife consents to riding with me now.

BT
 

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230 G BGS 300G TDI
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That sounds more like mine, slap an itercooler on it and see a major difference on the highway.
How did you modify the exhaust out of interest.
And I guess you won't be needing this mil box then
 

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TJs, FJ40s, JGCs, G500
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I might be interested in the mil box - drop me a line over my mail box.

Harald
 

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85 300GD 83 300TD
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Is the engine a rebuilt prior to installation or a used unit? If it is rebuilt it will be a while before you see it's potential power and torque. Did you open the exhaust all the way back? What diameter of pipes are you running?
The exhaust valves on the turbo 617A need to be set a bit looser than the non-turbo motor. I use (engine cold) 0.35mm or 0.014 in. for the turbo exhaust valves and 0.10mm or 0.004 in. intake. These values have worked well for several hundred thousands of miles on our TD Turbodiesel. These motors are very sensitive to valve adjustment and run the best when they are set spot on. If the motor has a newly rebuilt top end check the valve lash again soon.

-Dai
 

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I fully agree with all the above, I dont think they are run in untill about 50000 miles.
? Have you experienced any valve tightening.
? What is your oil consumption like.
 

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1981 300GD
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Discussion Starter #8
4x4rancher - 3/6/2005 10:19 AM

That sounds more like mine, slap an itercooler on it and see a major difference on the highway.
How did you modify the exhaust out of interest.
And I guess you won't be needing this mil box then
Dennis did a custom exhaust that followed the original routing through the gas tank out back. Diameter on the pipe was the same as the sedan the engine came from - believe it was 2.5". It was tight, but it worked.
 

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1981 300GD
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Discussion Starter #9
Dai - 3/6/2005 4:25 PM

Is the engine a rebuilt prior to installation or a used unit? If it is rebuilt it will be a while before you see it's potential power and torque. Did you open the exhaust all the way back? What diameter of pipes are you running?
The exhaust valves on the turbo 617A need to be set a bit looser than the non-turbo motor. I use (engine cold) 0.35mm or 0.014 in. for the turbo exhaust valves and 0.10mm or 0.004 in. intake. These values have worked well for several hundred thousands of miles on our TD Turbodiesel. These motors are very sensitive to valve adjustment and run the best when they are set spot on. If the motor has a newly rebuilt top end check the valve lash again soon.

-Dai
Engine was used with a rebuild about 25k miles ago according to the fellow that owned the sedan. Exhaust was opened to the original spec (2.5" if I remember, but could be wrong)
 

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1981 300GD
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Discussion Starter #10
4x4rancher - 3/6/2005 1:23 AM

I fully agree with all the above, I dont think they are run in untill about 50000 miles.
? Have you experienced any valve tightening.
? What is your oil consumption like.
Haven't driven far enough yet to be able to tell. Give me another couple weeks. Will be driving it to work for a couple of weeks so I get a feel for it.
 

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1981 300GD
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Discussion Starter #11
4x4rancher - 3/6/2005 1:23 AM

I fully agree with all the above, I dont think they are run in untill about 50000 miles.
? Have you experienced any valve tightening.
? What is your oil consumption like.
Haven't driven far enough yet to be able to tell. Give me another couple weeks. Will be driving it to work for a couple of weeks so I get a feel for it.
 
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