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Old 08-03-2022, 10:53 PM
coconup coconup is offline
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Question VE refurbished injection pump cold start device saga 🧐

Hi forum, I am in the process of rebuilding a D24TIC engine (my first time) and I bought this refurbished pump off of eBay from what I would think is a reputable seller (6k feedbacks and 100% positive rate).

The pump looks mint, but when I came to the part in the Volvo manual where I have to disconnect the cold start device, I noticed this came already in the disconnected position - despite being under tension. The CSD lever cannot be moved in either direction even when applying a lot of force.

As an extra bit of info (maybe irrelevant), the ball stud on the CSD lever does not touch the downward tab of the throttle arm, so I assume the cold start device is currently in the "warm" position.

Please check this video to understand what I mean: https://www.youtube.com/watch?v=TrSQ86VkxbQ

And here the illustration in the Volvo manual as part of timing the pump:


I contacted the seller (the name is turbo_lv on eBay) and they insist the pump is assembled correctly.

Did anyone else buy one of these and ran into the same issue? Or am I missing something? Very thankful for any tip (or confirmation that this is indeed not right)

Last edited by coconup; 08-03-2022 at 10:55 PM. Reason: Adding ebay link
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Old 08-04-2022, 07:42 AM
BogfordGarage BogfordGarage is offline
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Hi, that's a smart looking pump in the video. Assuming the seller is correct in that it has been set correctly then it my well be that you need to apply a fair bit of force to get the cable stays into the connected position as it is cold, there is an awful lot of spring tension in the cold start device. You will know immediately on first start up if it has been set correctly as the engine will start at about 950rpm and should start quickly without too much or no smoke. Hope this helps and there is something I'm over looking. Cheers
Tristan
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Old 08-04-2022, 10:19 AM
ngoma ngoma is offline
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That CS lever can be extremely difficult to turn unless the IP is spinning.
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Old 08-04-2022, 11:34 PM
coconup coconup is offline
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Thanks for the answers! As I wrote above though, the ball stud on the CSD lever does not touch the throttle arm - which is resting on its screw on the pump body. Am I wrong in thinking this means the CSD is already in the warm position?

If it were in the warm position, I would expect to be able to push the lever towards the cold position (i.e. to the left), regardless of how hard it is to push or pull the metal wire that connects it to the CSD. But the lever itself also won't budge even under a lot of pressure.
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Old 08-05-2022, 10:28 AM
ngoma ngoma is offline
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Can you push the lever in either direction?

I will repeat, "That CS lever can be extremely difficult to turn unless the IP is spinning."
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Old 08-05-2022, 05:26 PM
v8volvo v8volvo is offline
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Quote:
Originally Posted by coconup View Post
Am I wrong in thinking this means the CSD is already in the warm position?
That could be the case but not necessarily. As you can see, there is a large adjustment range for the ball stud on the top of the CS lever that provides the idle speed "bump up" when in cold position.

Thus if that ball stud has been incorrectly adjusted back away from the throttle lever (sometimes we see this if the system has failed in the cold position and someone wants to regain regular idle speed but doesn't know how to disconnect the linkage cable), the CS lever could be in the cold/advanced position without causing contact between the ball and the throttle lever.

The photos of your pump in the ebay auction show that the CS linkage is already disconnected as you correctly pointed out. So, normally that would mean the lever is in the cold position. However, usually when the linkage is disconnected that results in some free movement available in the lever. It also usually causes the lever to rest against its sheetmetal stop tab, which yours is not. I would say that lever is not reaching the fully disengaged position even with the CS cable end disconnected. It's somewhere between what we would think of as the "full cold" position and the "full warm" position that should be obtained when the cable is disconnected like it is. Since this is a rebuilt fresh pump, I guess that means the CS system may have been incorrectly set by the rebuilder and you may need to loosen that cable.

(Or have a Bosch shop do this for you if you are understandably not comfortable playing with the forbidden adjustment. )
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Old 08-06-2022, 12:31 AM
coconup coconup is offline
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Quote:
Originally Posted by v8volvo View Post
That could be the case but not necessarily. As you can see, there is a large adjustment range for the ball stud on the top of the CS lever that provides the idle speed "bump up" when in cold position.

Thus if that ball stud has been incorrectly adjusted back away from the throttle lever (sometimes we see this if the system has failed in the cold position and someone wants to regain regular idle speed but doesn't know how to disconnect the linkage cable), the CS lever could be in the cold/advanced position without causing contact between the ball and the throttle lever.

The photos of your pump in the ebay auction show that the CS linkage is already disconnected as you correctly pointed out. So, normally that would mean the lever is in the cold position. However, usually when the linkage is disconnected that results in some free movement available in the lever. It also usually causes the lever to rest against its sheetmetal stop tab, which yours is not. I would say that lever is not reaching the fully disengaged position even with the CS cable end disconnected. It's somewhere between what we would think of as the "full cold" position and the "full warm" position that should be obtained when the cable is disconnected like it is. Since this is a rebuilt fresh pump, I guess that means the CS system may have been incorrectly set by the rebuilder and you may need to loosen that cable.

(Or have a Bosch shop do this for you if you are understandably not comfortable playing with the forbidden adjustment. )
@v8volvo thanks a lot for the detailed answer. Those are the conclusions I came to as well, I am a bit pissed that the seller keeps on denying any mistake on their end but I guess I'll have to just fix it myself. I will try pouring hot water into the CSD to see if it relaxes at all, so to determine whether it is currently in cold or warm position, and then adjust the setting myself. I found instructions on how to do that at pages 168-171 of the greenbook and I'll give it a shot.

What I'm not fully understanding though is (at least) one thing: is the CSD lever the only thing supposed to move when going from cold to warm? Is everything else static? I guess it's clear to me how the idle compensation works (via the stud) but I'm not fully grasping how the timing advance is achieved.
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Old 08-06-2022, 08:09 AM
BogfordGarage BogfordGarage is offline
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In response to how the timing works I'm sure somone could explain it better than me but... There is a timing piston the lies perpendicular to the rest of the pump drive direction. The cold start lever moves the piston slightly from one side of the pump to the other which inturn rotates the cam plate within the pump housing. This inturn advances or retards the plunger strokes changing when the injection lines are pressured thus making happen earlier in in the other direction later.
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