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  #31  
Old 01-21-2021, 01:31 PM
jpliddy jpliddy is offline
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Default smoke screw

thanks for that post V8volvo . well you may be close to the issues i have . so last thing 1st i changed the fuel filter a few days ago for a VW MANN filter ,no air bubbles now ! when got the car back the plastic cover over the smoke screw was missing , they found it and put it back on ! so do they have to wind the screw off to release the throttle shaft? so they have to reposition it ,
your description seems right . so i woud be willing to try the slight adjustment of the smoke screw with your guidance ,
so i will go down the path of the auto box playing up , and see what the smoke screw path can do if im very careful with it,
good advice on what the wrong path can take you in time and costs the more advice we get we can make a better judgement hopefully
regards jim
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  #32  
Old 01-21-2021, 07:50 PM
RedArrow RedArrow is offline
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Quote:
Originally Posted by jpliddy View Post
thanks for the input .
yes car does not seem to drop down climbing the hill now.
reves are 2300 rpm when climbing hill . if its kickdown problem is that a big job to set up . cold start was good this morning .my friend drove it up the hill this morning said it was not to bad . as it got power on the straight flat.
seems like we are heading back to the lockdown . but i do need a person who knows these set ups really well to look at things from a different angle to say
what he thinks ,!

Completely off-topic (sorry) ... BUT VERY IMPORTANT:

Be careful what you do in the mornings (even on a warm&sunny Summer morning)! I read words such as `coldstart`, `morning`, `RPM`, revs, `climbing a hill` etc.
I really hope that you normally start the car and let it idle for at least 10-15 minutes before climbing hills or getting on any road that has speed limits above 50KM/H. Raising RPM to 2300 soon after the diesel got coldstarted is NOT OKAY, also equally NOT OKAY even if you simply idled without the car moving. Not to mention attempting climbing a hill with a coldstarted diesel engine at 2300 RPM.
Maybe you missed telling us that you let it idle before taking it on that ``test``.

Driving these cars `hard` when cold, is recipe for serious trouble and recipe for very very premature wear internally and will affect major engine components.
A coldstarted diesel engine will not stay healthy for too long for those who drive their cold diesel too hard or simply too `early` (not waiting for it to warm up which usually takes 5-8miles of **gentle** low-RPM driving OR min 10-15mins of idling (often, even longer stationary idling itself won`t even warm up the car to operating temps), but all of this can vary based on temperatures, climate etc. )

Where I grew up we always go to the seller`s house when we buy his/her car and evaluate things before making decisions. Asking questions like how long he had the vehicle etc, how long had he lived at that location etc. Questions that help the buyer imagine what scenarios may have happened daily in the Winters (and honestly every season it happens). This includes learning what profession he has, how many cars he drives, how far from his house the closest major road is (higher speed limits with a cold engine?!!), also checking this: are there any substantial hills in the area en-route to that main road where he would need to drive the car through soon after the coldstart (because of cold climate mornings when an impatient owner can(=will) ruin a diesel engine, simply by climbing that hill with higher than normal RPMs, ruining the engine from the inside out... day by day, slowly but surely. It now may all sound like `ugh such an ocd diesel bug person` , but damage is guaranteed for the owners with bad habits.

I am sure you aren`t one of those bc you had this car for 279000 kilometers already.

I just felt like mentioning this for those who either never had a diesel and they have one now, and for those who don`t think much of what`s bad/best for their diesel car.

Wishing the best of luck to figure out what is wrong with your beloved Volvo.
I also put my bets on the injection pump being misadjusted or maybe a little worn by now. Would also get the injectors rebuilt by a Bosch professional, one future day. makes a huge difference but focus on resetting the IP to the best possible values and dont give up on your rare diesel Volvo.

On a side note, don`t let anyone touch the tranny, or at least not for now. Dealing with issues one by one is tons easier and it makes much more sense than changing multiple setups of several components at the same time, then not really knowing what mod resulted having a certain symptom(s).

There`s a high chance you will get things figured out soon AND you`ll have it running better than before. But if I listen to my heart I must say I personally don`t trust the competence of those who serviced the pump (*based on things you shared with us).

Last edited by RedArrow; 01-21-2021 at 08:28 PM.
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  #33  
Old 01-21-2021, 09:59 PM
ngoma ngoma is offline
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Quote:
Originally Posted by RedArrow View Post
Driving these cars `hard` when cold, is recipe for serious trouble and recipe for very very premature wear internally and will affect major engine components.
Agreed, yes, very good warning. OP understands this, but good to repeat it for others that may not.

Quote:
Originally Posted by RedArrow View Post
I really hope that you normally start the car and let it idle for at least 10-15 minutes before climbing hills or getting on any road that has speed limits above 50KM/H.
Don't agree so much here, as diesel engine will not generate much heat when idling, especially from cold start. Need to work to generate heat. Excessive idling can cause its own problems, namely from Wet Stacking. We have discussed this here before. Better to drive it lightly immediately after the idle smooths out after cold start, progressively working it harder, waiting to boot it hard only after it has thoroughly evenly warmed up to operating temp.

Quote:
Originally Posted by RedArrow View Post
... min 10-15mins of idling (often, even longer stationary idling itself won`t even warm up the car to operating temps), but all of this can vary based on temperatures, climate etc. )
Kind of what I am saying-- idling from cold start won't bring engine up to operating temps in a reasonable time, and runs the risk of creating other problems. So why confuse people?
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  #34  
Old 01-22-2021, 12:22 AM
jpliddy jpliddy is offline
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Quote:
Originally Posted by RedArrow View Post
Completely off-topic (sorry) ... BUT VERY IMPORTANT:

Be careful what you do in the mornings (even on a warm&sunny Summer morning)! I read words such as `coldstart`, `morning`, `RPM`, revs, `climbing a hill` etc.
I really hope that you normally start the car and let it idle for at least 10-15 minutes before climbing hills or getting on any road that has speed limits above 50KM/H. Raising RPM to 2300 soon after the diesel got coldstarted is NOT OKAY, also equally NOT OKAY even if you simply idled without the car moving. Not to mention attempting climbing a hill with a coldstarted diesel engine at 2300 RPM.
Maybe you missed telling us that you let it idle before taking it on that ``test``.

Driving these cars `hard` when cold, is recipe for serious trouble and recipe for very very premature wear internally and will affect major engine components.
A coldstarted diesel engine will not stay healthy for too long for those who drive their cold diesel too hard or simply too `early` (not waiting for it to warm up which usually takes 5-8miles of **gentle** low-RPM driving OR min 10-15mins of idling (often, even longer stationary idling itself won`t even warm up the car to operating temps), but all of this can vary based on temperatures, climate etc. )

Where I grew up we always go to the seller`s house when we buy his/her car and evaluate things before making decisions. Asking questions like how long he had the vehicle etc, how long had he lived at that location etc. Questions that help the buyer imagine what scenarios may have happened daily in the Winters (and honestly every season it happens). This includes learning what profession he has, how many cars he drives, how far from his house the closest major road is (higher speed limits with a cold engine?!!), also checking this: are there any substantial hills in the area en-route to that main road where he would need to drive the car through soon after the coldstart (because of cold climate mornings when an impatient owner can(=will) ruin a diesel engine, simply by climbing that hill with higher than normal RPMs, ruining the engine from the inside out... day by day, slowly but surely. It now may all sound like `ugh such an ocd diesel bug person` , but damage is guaranteed for the owners with bad habits.

I am sure you aren`t one of those bc you had this car for 279000 kilometers already.

I just felt like mentioning this for those who either never had a diesel and they have one now, and for those who don`t think much of what`s bad/best for their diesel car.

Wishing the best of luck to figure out what is wrong with your beloved Volvo.
I also put my bets on the injection pump being misadjusted or maybe a little worn by now. Would also get the injectors rebuilt by a Bosch professional, one future day. makes a huge difference but focus on resetting the IP to the best possible values and dont give up on your rare diesel Volvo.

On a side note, don`t let anyone touch the tranny, or at least not for now. Dealing with issues one by one is tons easier and it makes much more sense than changing multiple setups of several components at the same time, then not really knowing what mod resulted having a certain symptom(s).

There`s a high chance you will get things figured out soon AND you`ll have it running better than before. But if I listen to my heart I must say I personally don`t trust the competence of those who serviced the pump (*based on things you shared with us).
hi red arrow
thanks for that comment. well the hill is half a mile from my house and its DOWN THE HILL when i leave home i so nothing to worry about there
. this is for all of you i messed with the ball stop lever that brings the cold stat on
yesterday . when the engine was hot im sorry it was wrong thing to do came out this morning to frosty weather and engine cold stat did not come on due to the position of the ball stop nut , its given out sunny today so i will let engine go cold and get it working again . hopefully . sorry again thanks for all your patience
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  #35  
Old 01-23-2021, 09:46 AM
v8volvo v8volvo is offline
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Quote:
Originally Posted by RedArrow View Post
Dealing with issues one by one is tons easier and it makes much more sense than changing multiple setups of several components at the same time, then not really knowing what mod resulted having a certain symptom(s).
Well said, agreed.

Quote:
Originally Posted by jpliddy View Post
when got the car back the plastic cover over the smoke screw was missing , they found it and put it back on ! so do they have to wind the screw off to release the throttle shaft? so they have to reposition it ,
your description seems right . so i woud be willing to try the slight adjustment of the smoke screw with your guidance
Yes exactly right, the smoke screw gets removed (or at least screwed a long ways out) in order to disassemble the top of the IP/throttle control system. So they would have had to do this during the service that was performed, and then they would have had to get it reinstalled to the same setting it had been.

Normally the way to do this, if one is working on the IP still installed on engine using "seat of the pants" methods, is to very carefully note the position angle of the smoke screw before disassembly, and then count the number of turns required to remove it from the pump upper section housing. Then one tries to reinstall it in exactly the same position and with the same number of turns, so as to have the system work as it did before.

(This is as opposed to the ideal scenario of bench calibration off the engine, where the pump settings could be configured precisely based on fueling/advance measurements.)

If the folks who worked on your pump didn't use this "count the turns" method, or didn't manage to get it just right, then it is very much possible that the setting is off from what was intended. Or even if they did use it, since there are new parts in the pump and there are lots of other little fine variables that can affect how the pump operates (eg minor changes in the installed position of the upper cover section onto the main pump body), it could still have resulted in a change in the relationship of accelerator position to injected fuel quantity.

All this to say, it would be a good idea to carefully experiment a little with the smoke screw and see if that can get the engine back to running like it did before. It sounds like you know where the smoke screw is on the pump, and how it works. You can try turning it inwards (clockwise) in small 1/8th turn increments (loosening and tightening the jam nut each time), then go for a drive after each change and see what the difference is in terms of response, power, transmission shift points, and exhaust smoke.

Your target with the adjustments is to improve throttle response and power, but not get to the point of excess exhaust smoke under load. If you floor the pedal from a stop and see a steady trail of dark smoke until the turbo boost rises, then you have turned it in too far. It's OK to have a small visible puff of smoke during the transient moment just as you snap the pedal to full load, but it should not do more than that and should clear up as soon as the car is in motion. That is the result you're looking for. Any kind of steady state operating condition should have completely clear exhaust. Excess visible smoke is wasted fuel, and causes very high exhaust and cylinder head temps and is hard on the engine. Don't be tempted to allow it to smoke, even if the power feels good. If you see smoke, you can back the screw off until you get to the sweet spot.

Let us know how that goes. Also be aware that changing the setting of the smoke screw will also result in minor changes to the engine idle speed. After you reach a satisfactory setting for the smoke screw, you may need to then make some final adjustments to the idle stop screw and/or the turnbuckle type linkage rod from the throttle spool to throttle lever and/or the position of the ball stud on the throttle lever to bring the warm idle speed back down to specified range. If your adjustments to the smoke screw cause a big increase in idle RPM, then you will want to make those other adjustments before test-driving the car, so as not to damage the transmission by engaging a gear with the engine racing.
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  #36  
Old 01-23-2021, 10:35 AM
jpliddy jpliddy is offline
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thanks for the information V8VOLVO yes i know where the fuel enrichment is .
i will see what i now think about adjusting that screw .
well latest news , i now have a very slight leak on the cold start at the bottom of where its bolted into the injection pump ,i take it that nut and cold start was removed the garage did say on a car that age and mileage that other leaks may occur i have spoken to garage they can do the job in a week , the leak is wetting the spring a bit and a bit wet on the pump moving on there is another small plate below that spring . SO SHOUD I TAKE IT BACKas i don't like to see any leaks a. but its only small .and hopefully they will fix the leak permanently as the cold start seals is a moving part on the pump it will wear out one day . he did say there are 2 seals on the cold start fitting 1 outer and 1 inner into the pump take it thats correct ,
regards jim
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  #37  
Old 01-23-2021, 01:02 PM
v8volvo v8volvo is offline
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Quote:
Originally Posted by jpliddy View Post
i take it that nut and cold start was removed

...

the garage did say on a car that age and mileage that other leaks may occur

...

he did say there are 2 seals on the cold start fitting 1 outer and 1 inner into the pump take it thats correct
Not necessarily were they removed if the work that was previously done only involved the throttle shaft seal, that's a different area of the pump and the cold start lever/shaft probably would not have been touched.

More likely this latest leak is a coincidence, just caused by age and time same as the first leak, and maybe also by winter weather. Cold temps always make leaks like this worse since the old rubber is harder and more brittle. Wintertime is common season to see new leaks appear, sometimes many all at once, as seems to be happening for your pump. As a matter of fact my 760 sedan also just sprung an injection pump leak a couple weeks ago during a stretch of cold weather.

Hence, the garage is right to tell you that other leaks may soon occur, as we have also mentioned here.

Correct in your last comment that there are two seals for the cold start area, one is a shaft seal similar to the throttle shaft seal, and the other is an O-ring sandwiched between the shaft housing cover plate and the main pump body. Both can leak and should be replaced if you have that area apart, although from your description the main leaker you have now is the smaller shaft seal. It *can* be done with the pump on the car, like the previous leak repair was, but....

As was noted earlier in the thread by a couple of us, at this point your best bet may be to get the pump pulled off the engine and completely resealed and recalibrated by a professional fuel injection service shop. You CAN continue to fix the leaks one at a time as they arise here and there, but doing it that way will be annoying and probably more costly, since you will continually be having to bring the car back for each new leak. Plus, there are also some seals on the pump that cannot be easily/safely accessed for replacement without removing the pump from engine, such as the one on the opposite side of the pump from the cold start area, the drive shaft seal, and the main head seal which can be the biggest leaker of all. And eventually those will give up too, since all the seals are the same age and obviously reaching end of their life. So you'll have to remove the pump from engine someday anyway. Best option probably to bite the bullet and have it all done in one shot, then you don't have to keep watching for and dealing with a continuing series of new leaks. And risking your heater hoses in the process.
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  #38  
Old 01-23-2021, 10:36 PM
ngoma ngoma is offline
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Quote:
Originally Posted by jpliddy View Post
SO SHOUD I TAKE IT BACKas i don't like to see any leaks a. but its only small .and hopefully they will fix the leak permanently as the cold start seals is a moving part on the pump it will wear out one day .
In my experience, they never get better by themselves, only worse. Except only once, where it was leaking when ran on 100% biodiesel, got better after switching to D2. That was a lucky one.
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  #39  
Old 01-24-2021, 06:48 AM
jpliddy jpliddy is offline
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Default cold start .diesel leak

hi just a thought if i was to buy the 2 seals from the diesel engineers ,woud it be safe for me to attempt to fix this latest leak myself bu taking nut of removing the cold start and spring , or is there something more complicated once i pull that from the pump . what do you think do you have any guidance then i can make a decision myself .
regards jim
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  #40  
Old 01-24-2021, 09:57 PM
ngoma ngoma is offline
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Why not?

If you're looking for a warning, here's one:

Like the throttle plate, the cold start lever is on a splined shaft so mark their orientation to each other before you remove the lever so you can reassemble it to the proper position without guessing.

And here's where I will give you:::::::::::::::::::::::::::::

Another plug for Thom Bryant's great photo essay on resealing the Bosch VE IP:

https://thosbryant.wordpress.com/201...-pump-re-seal/

He goes into it in great detail and covers the important points. More even.

Review carefully the section on resealing the cold start lever and see if you are up to it.
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