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Old 07-09-2020, 06:10 PM
RedArrow RedArrow is offline
Senior Member
 
Join Date: Jan 2013
Location: New York
Vehicle: 1986 Volvo 745 TD
Posts: 900
Default Nice day

Yesterday I ran the d24t engine for over two hours.

Yes, I took videos.
No, no d24 harm was done during the video. Absolutely no revving on a coldstarted cold diesel engine.

The engine was properly and thoroughly warmed up before I revved it. I also confirmed this by constantly monitoring the temperatures using an infrared thermometer at multiple spots: on the engine, the coolant, the cylinder head etc (before and while and after running it). As I said in my earlier post, a strong electric blockheater was also plugged in, for 20 minutes (before firing it up... the engine ). Outside temps were 85F yesterday AND I ran the engine for well over 30minutes before doing any kind of revving.

Recorded by a cheaper cellphone camera, and YT reduced the quality as well, but vids give a good idea about how it runs now.

The engine starts really well, almost literally without cranking. Once it fires up there`s a little smoke that goes away very soon.
It holds idle and runs stable, on all cylinders, no coughing, no misses, no scary knocking at all. This makes me feel good as the refurb was done well and was worthwhile.

Through all these sessions of running the motor, I haven`t noticed gases ending up traveling with the coolant to the reservoir. That`s awesome, and it sounds healthy. Oil feels really new and clean (it is, I use Mobil-1 TD TRUCK fully synthetic 5W40), coolant is clear.
Never stalled and no leaks of fuel (except seeping at cyl 5 injector where I think someone once overtightened the hard line on top, so I need to redo it or fix it or swap it with my spare set).


*************************VIDEOS from yesterday***************************************** *******

Video 1 of 8
This is the `cold`-start. Engine had been sitting for a full day. Fired up without much need for long cranking. Blockheater was On for 20mins (before the start-up). 10seconds of manually operated glowplugs. Pump not loosing prime overnight.
Running on diesel fuel. Timed to 0.94, the coldstart device is functioning.
https://www.youtube.com/watch?v=LtmaQo19sAM

Video 2
WARM engine.
It idles high, yes. Adjusted it later.
https://www.youtube.com/watch?v=i0XFAnGp-k4

Video 3
Still idling high AND THE REVS APPEAR TO BE STICKY, RPMS HANG FOR A MOMENT WHEN I RELEASE THE THROTTLE. RETURNING TO IDLE IS SMOOTH BUT TOO SLOW. Very annoying and not-so-good news if you think of a runaway situation. I did try choking the engine using a wood block in front of the turbo inlet BUT engine would not get fully choked to a full stop. It may have sucked air where the large cotter-pin is. IDK. Very annoying. Especially the sticky RPMS when I release the throttle. Whatever RPMs I rev it up to, doesnt matter to what RPM, it feels sticking right at that RPM for a moment, before start returning to normal idle.
https://www.youtube.com/watch?v=_x0qJfFrZUA

Video 4
How it starts when warm. Idle remains high no matter how much I fiddle with linkage. I first thought it was a low idle situ due to linkage. Then it seemed like a high idle situ. Then it sounded like an overfuel issue.
https://www.youtube.com/watch?v=3__M4tKBY2M

Video 5
Returning to idle is still too sticky and slow. Otherwise it runs great, strong and stable.
https://www.youtube.com/watch?v=u4FX50cd8rM

Video 6
no more sticking of throttle. No more sticky hanging RPM. Runs better. It was the IP adjusting screw being clogged up, sticky and or stuck.
It all solved later: I turned it quite a lot, first clockwise and then back CCW then CW then again and finally set it to almost where it exactly was but a backed off the fuel a bit, then tightened the nut. By doing this seemingly unwanted and excessive turning of the screw, in both directions and multiple times, it all became unclogged and immediately better. No more sticking.
To my taste, it was turned too much clockwise and that might have been the reason why I originally first adjusted the throttle linkage to `shorter`(when I got it running for the very very first time 3w ago). BC my other d24t has CS device disconnected, back then I didn`t think of that as being the reason. But, it was the coldstart device keeping this d24t idle higher at coldstart, plus this IP screw was turned CW too much. Those two, together, caused it to run much worse than how it runs and sounds now. It runs very well. Sounds better in real life than it does in video.
https://www.youtube.com/watch?v=PCHH8Wzh1KE


Video 7
Now, With less fears of a malfunctioning IP fuel screw causing a runaway, it`s time to rev the warm engine.
It had been run for over an hour at this point or closer to 2hrs. It is not cold. Temps monitored.
https://www.youtube.com/watch?v=tHRj5w3zlg0

Video 8
Boring video but may be useful to some of you. Shows the TEMPERATURES I measured after running the engine for an extended period of time (in Celsius). Not much revving besides what you have seen in the videos. RPMs probably reached 5500-6000 at some point but just for a short moment, really. It appears to be real peppy, well adjusted and joy to hear. Nice strong revs that sound healthy. Didn`t eat motor oil, level later found to be the same as before. No sign of noticable blowby. One of the video shows that, too.
It started running cleaner and cleaner every time. Also, probably now the rings started to feel more `at home`, the freshly painted parts all cured and are now baked; deposits of carbon (if any) burnt away, even if at least just a little bit. I`d be confident using this engine for a nice brick Volvo now. I`m very happy with the results.
https://www.youtube.com/watch?v=ZArDeRsn--s

I like the results.
Thanks to all who followed my progress! I`m expecting to be updating this thread at a slower rate from now on. Have some bricks to deal with.
For this forum and its members here, for always being there; thank you. It`s awesome to read answers, get advice, receive help, find motivation and also help each other as much as we can. To keep these d24, d24t cars running.

Last edited by RedArrow; 07-09-2020 at 10:13 PM. Reason: Video links added.
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