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  #21  
Old 02-22-2021, 02:15 PM
ngoma ngoma is offline
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Originally Posted by ukvolvo View Post
Either way i am not expecting a modern style. More powerful truck

The d24 appealed to me as its just such a brute of a old skool engine.
Well yes it is an old skool engine but in a different vein than the old stump pullers. Not much power or torque down low like the common stereotypical old skool diesel industrial engines; these like to rev more, smoother, quieter and less smoky.

You may want to study what the VW 4-cyl diesel gearhead crowd has done with their (similar bones) versions of these engines (the early pre-TDI versions). Much larger population; they have experimented more with VNT, porting, IP, manifold and exhaust mods., etc.
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  #22  
Old 02-23-2021, 04:54 AM
ukvolvo ukvolvo is offline
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Originally Posted by ngoma View Post
Well yes it is an old skool engine but in a different vein than the old stump pullers. Not much power or torque down low like the common stereotypical old skool diesel industrial engines; these like to rev more, smoother, quieter and less smoky.

You may want to study what the VW 4-cyl diesel gearhead crowd has done with their (similar bones) versions of these engines (the early pre-TDI versions). Much larger population; they have experimented more with VNT, porting, IP, manifold and exhaust mods., etc.
I have another 2 restos to finish so no heavy modding haha I will just do my best to get her as nippy as possible

Had a experience this morning that summarised the way it drives well.

Let her run for 10 on the drive to warm but still cold so gently driving but briskly.

On my way and i get stuck behind a turnip crawling, then half way up a reasonably steep hill they pull in and make me brake. Literally from 5th to 2nd gear nothing at all no torque to be had and a huge que behind me as i try to get back up to speed. It literally crawled up to speed up a hill, surely that is not right? It is completely useless on anything beyond flat although alot nippier since my work once going.

I would not dare tow a kitten on rollerskates with this if thats all the torque they have

When cold its a nightmare as you cant use the revs to claw some power


Mick
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  #23  
Old 02-23-2021, 10:45 AM
v8volvo v8volvo is offline
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That does sound much too slow. When running right, even stock, they are reasonably stout. Not fast, but easily able to get up to the speed of traffic with minimal drama.

Either a mis-adjusted injection pump or incorrect cam or IP timing, those would be my vote for most likely. Other common causes for "low power" would be restriction in the intake air, exhaust, or fuel supply, OR a turbocharger issue/failure as you mentioned. HOWEVER, with all of those, you would typically see the power loss be even worse at high RPM, when the engine would start to really choke on the lack of air/fuel flow.

In your case, it sounds like the opposite -- very weak at low RPM, but if you can get the revs up enough, it finally starts to pull a little better. Right?

So it's more probable that it is an engine tune issue for yours. Internal IP misadjustment, or incorrect injection pump static timing, or even external misadjustment of the throttle linkage causing the pump not to reach the full "throttle" setting even when the accelerator is floored. You could check last one that easily enough with a helper. The other checks will require a little more in-depth work.

VERY common with these engines is someone attempting to replace a timing belt or R&R the injection pump without the required special tools and methods, and then the timing is off as a result and majorly affects performance. So on your list of things to check, injection timing (using dial indictator) is near the top. If that is confirmed within spec, then you would proceed to check turbo boost, and then finally to try adjusting the "smoke screw" on the pump and see if you can regain some power. But you only want to mess with those things after confirming correct base engine timing.

If injection timing is found to be wrong then that almost certainly means cam timing is also wrong. At that point you would want to just dig in for the whole timing belt refresh job since you say you plan on doing it anyway, and then continue with further diagnostics after that's done.

Do you ever see smoke from the exhaust? When and what color? How is the cold starting of the engine, easy, difficult, smoky, clean?

Quote:
Originally Posted by ukvolvo View Post
Ive been offered a 3" exhaust for it. I imagine it would sound absolutely, diabolically ludicrous with one standard downpipe to 3" hahaha
Yes they sound wonderful with the exhaust opened up.
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  #24  
Old 02-24-2021, 01:57 AM
ukvolvo ukvolvo is offline
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Quote:
Originally Posted by v8volvo View Post
That does sound much too slow. When running right, even stock, they are reasonably stout. Not fast, but easily able to get up to the speed of traffic with minimal drama.

Either a mis-adjusted injection pump or incorrect cam or IP timing, those would be my vote for most likely. Other common causes for "low power" would be restriction in the intake air, exhaust, or fuel supply, OR a turbocharger issue/failure as you mentioned. HOWEVER, with all of those, you would typically see the power loss be even worse at high RPM, when the engine would start to really choke on the lack of air/fuel flow.

In your case, it sounds like the opposite -- very weak at low RPM, but if you can get the revs up enough, it finally starts to pull a little better. Right?

So it's more probable that it is an engine tune issue for yours. Internal IP misadjustment, or incorrect injection pump static timing, or even external misadjustment of the throttle linkage causing the pump not to reach the full "throttle" setting even when the accelerator is floored. You could check last one that easily enough with a helper. The other checks will require a little more in-depth work.

VERY common with these engines is someone attempting to replace a timing belt or R&R the injection pump without the required special tools and methods, and then the timing is off as a result and majorly affects performance. So on your list of things to check, injection timing (using dial indictator) is near the top. If that is confirmed within spec, then you would proceed to check turbo boost, and then finally to try adjusting the "smoke screw" on the pump and see if you can regain some power. But you only want to mess with those things after confirming correct base engine timing.

If injection timing is found to be wrong then that almost certainly means cam timing is also wrong. At that point you would want to just dig in for the whole timing belt refresh job since you say you plan on doing it anyway, and then continue with further diagnostics after that's done.

Do you ever see smoke from the exhaust? When and what color? How is the cold starting of the engine, easy, difficult, smoky, clean?



Yes they sound wonderful with the exhaust opened up.
Now define wonderful haha as in wonderful and sporty or ricer as you guys say with a 4" backbox loud haha. 3" is huge so its tempting but worrying.

And yes that sums her up well, flat low down. I need to get all the tools together and get setting up it seems. Still haven't tested boost yet as I've been so busy.

Excuse my ignorance but how could the cam timing be out? do you mean by one tooth for example on the belt? I know the ip pump is adjustable of course but i thought cam was fixed unless you like banana shaped valves.

I have found the how to videos confusing for these engines as they jump from cam to pump timing and I would much prefer to do each job separate.

Could you tell me the basic tools needed to do the timing belt, rear pump belt, pump timing and water pump buddy please? Does the injector pump need timing on the clock and in a different way also? like i said the videos for timing jump about a bit. The timing with a clock looks straight forward enough, as a toolmaker I've used it them plenty plenty.

Mick
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  #25  
Old 02-24-2021, 10:40 AM
jpliddy jpliddy is offline
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Quote:
Originally Posted by v8volvo View Post
That does sound much too slow. When running right, even stock, they are reasonably stout. Not fast, but easily able to get up to the speed of traffic with minimal drama.

Either a mis-adjusted injection pump or incorrect cam or IP timing, those would be my vote for most likely. Other common causes for "low power" would be restriction in the intake air, exhaust, or fuel supply, OR a turbocharger issue/failure as you mentioned. HOWEVER, with all of those, you would typically see the power loss be even worse at high RPM, when the engine would start to really choke on the lack of air/fuel flow.

In your case, it sounds like the opposite -- very weak at low RPM, but if you can get the revs up enough, it finally starts to pull a little better. Right?

So it's more probable that it is an engine tune issue for yours. Internal IP misadjustment, or incorrect injection pump static timing, or even external misadjustment of the throttle linkage causing the pump not to reach the full "throttle" setting even when the accelerator is floored. You could check last one that easily enough with a helper. The other checks will require a little more in-depth work.

VERY common with these engines is someone attempting to replace a timing belt or R&R the injection pump without the required special tools and methods, and then the timing is off as a result and majorly affects performance. So on your list of things to check, injection timing (using dial indictator) is near the top. If that is confirmed within spec, then you would proceed to check turbo boost, and then finally to try adjusting the "smoke screw" on the pump and see if you can regain some power. But you only want to mess with those things after confirming correct base engine timing.

If injection timing is found to be wrong then that almost certainly means cam timing is also wrong. At that point you would want to just dig in for the whole timing belt refresh job since you say you plan on doing it anyway, and then continue with further diagnostics after that's done.

Do you ever see smoke from the exhaust? When and what color? How is the cold starting of the engine, easy, difficult, smoky, clean?



Yes they sound wonderful with the exhaust opened up.
hi V8VOLVO i read middle paragraph with interest .saying misajustment of the THROTTLE LINKAGE .as my car after the throttle shaft leak seems to suffer this problem lack of power when accelerator is floored . you mention this can be checked with a helper ,what am i looking for and does engine need to be running , as revs could go to high for my ZF auto box
regards jim
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  #26  
Old 02-24-2021, 12:03 PM
ngoma ngoma is offline
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Now let's don't overlook the questions v8volvo asked. Please answer. They are not joking around, but to help assemble clues to eventually leading us to the actual problem area. Unless you want to sit around benchracing talking about 3" exhaust all day.

Quote:
Originally Posted by v8volvo View Post
Do you ever see smoke from the exhaust? When and what color? How is the cold starting of the engine, easy, difficult, smoky, clean?


Quote:
Originally Posted by ukvolvo View Post
Excuse my ignorance but how could the cam timing be out? do you mean by one tooth for example on the belt? I know the ip pump is adjustable of course but i thought cam was fixed unless you like banana shaped valves.
The camshaft pulleys are not keyed, allowing the camshaft to be clocked to infinite positions.
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  #27  
Old 02-24-2021, 12:12 PM
ngoma ngoma is offline
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Originally Posted by jpliddy View Post
hi V8VOLVO i read middle paragraph with interest .saying misajustment of the THROTTLE LINKAGE .as my car after the throttle shaft leak seems to suffer this problem lack of power when accelerator is floored . you mention this can be checked with a helper ,what am i looking for and does engine need to be running , as revs could go to high for my ZF auto box
regards jim
The same method I suggested in your thread "Cold Start"
https://www.d24t.com/showpost.php?p=14646&postcount=7

Quote:
Originally Posted by ngoma View Post
Here's something else for you to try: (engine off) Have a helper press the accelerator pedal to the floor while you watch the accelerator arm on the IP. While they are holding it to the floor, see if you can rotate the accelerator arm on the IP even further. Is the pedal able to rotate the throttle arm all the way by itself? Maybe there is too much slack in the pedal cable or other (max WOT?) adjustment?
If you didn't understand it you should have mentioned it in that thread. Let's try not to derail ukvolvo's thread here too much. We're already at 3 pages and nothing really achieved.
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  #28  
Old 02-25-2021, 01:32 AM
ukvolvo ukvolvo is offline
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Quote:
Originally Posted by ngoma View Post
Now let's don't overlook the questions v8volvo asked. Please answer. They are not joking around, but to help assemble clues to eventually leading us to the actual problem area. Unless you want to sit around benchracing talking about 3" exhaust all day.






The camshaft pulleys are not keyed, allowing the camshaft to be clocked to infinite positions.

My goodness this engine is quirky, my Dad a mecanic of decades was speechless when I told him it's a morse taper pulley haha. A rant about german engineering followed

Yes agreed exhaust is way way down there priority wise. Never heard of bencracing before, sounds cheaper.

And the car behaviour wise.

Cold starts- Fires excellent once plugs warmed, Sometimes not a drop of smoke sometimes a bit on first start thats white/ blue which clears in 10 seconds maybe

It is not burning huge amounts as the dipstick has not moved in hundreds of miles so far.

I've been told it puts out just a little blue smoke at acceleration at times. When i left my friends drive he said it puffed just a smige on each gearchange/ throttle press as i pulled off slow. I went through 1st and 2nd very slow for what he saw

The main body of it seems good mechanically thankfully and its very likely the timing is out i bet knowing how they are set up now.

It did one unusual thing today. It only warmed up 30-40% on the gauge today after my commute so thermostat despite been done jn 2018 is another job whilst belts etc are done.

My apologies if i miss some questions, i am replying on a mobile mostly at work and typing is fun

Last edited by ukvolvo; 02-25-2021 at 01:35 AM.
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  #29  
Old 02-26-2021, 08:25 AM
ukvolvo ukvolvo is offline
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Quote:
Originally Posted by v8volvo View Post

Do you ever see smoke from the exhaust? When and what color? How is the cold starting of the engine, easy, difficult, smoky,


Yes they sound wonderful with the exhaust opened up.
I answered but didnt quote you bud sorry

It has used a 5-7 mm of dipstick in a few weeks doing daily runs totaling at least 500 miles.
Not too bad.


Mick
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  #30  
Old Today, 01:19 AM
ukvolvo ukvolvo is offline
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Quote:
Originally Posted by v8volvo View Post
That does sound much too slow. When running right, even stock, they are reasonably stout. Not fast, but easily able to get up to the speed of traffic with minimal drama.

Either a mis-adjusted injection pump or incorrect cam or IP timing, those would be my vote for most likely. Other common causes for "low power" would be restriction in the intake air, exhaust, or fuel supply, OR a turbocharger issue/failure as you mentioned. HOWEVER, with all of those, you would typically see the power loss be even worse at high RPM, when the engine would start to really choke on the lack of air/fuel flow.

In your case, it sounds like the opposite -- very weak at low RPM, but if you can get the revs up enough, it finally starts to pull a little better. Right?

So it's more probable that it is an engine tune issue for yours. Internal IP misadjustment, or incorrect injection pump static timing, or even external misadjustment of the throttle linkage causing the pump not to reach the full "throttle" setting even when the accelerator is floored. You could check last one that easily enough with a helper. The other checks will require a little more in-depth work.

VERY common with these engines is someone attempting to replace a timing belt or R&R the injection pump without the required special tools and methods, and then the timing is off as a result and majorly affects performance. So on your list of things to check, injection timing (using dial indictator) is near the top. If that is confirmed within spec, then you would proceed to check turbo boost, and then finally to try adjusting the "smoke screw" on the pump and see if you can regain some power. But you only want to mess with those things after confirming correct base engine timing.

If injection timing is found to be wrong then that almost certainly means cam timing is also wrong. At that point you would want to just dig in for the whole timing belt refresh job since you say you plan on doing it anyway, and then continue with further diagnostics after that's done.

Do you ever see smoke from the exhaust? When and what color? How is the cold starting of the engine, easy, difficult, smoky, clean?



Yes they sound wonderful with the exhaust opened up.
This morning was a cold damp morning. Car started first time but was a little rough for a minute and the car smoked for a minute maybe, Mainly clear white with hues of blue, but when i start her at work theres not a drop usually. I am keeping a super super close eye on water use as ive marked the tank. Hopefully it is merely condensation clearing and it is not using water. My drive is so uneven its hard to get a 100% same read every time.

Could the rough 30-60 seconds be valve stem oil seals and the excess thats dripped overnight burning off? Or injector rough ar start?

I will check every morning now as it usually smokes for a very brief spell blue and is fine.
Mick

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