ACSD: The Mysterious device.. (4 Viewers)

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Calgary, Alberta - Canada
Re: my previous post about RPM increase
https://forum.ih8mud.com/diesel-tech-24-volts-systems/261832-unexplained-increase-rpm.html

The ACSD seems to be the likely culprit. I have done a bit more diggin and it seems that when the thermal wax inside the ACSD fails, it retains the high RPM and the timing advance even after the engine is fully warmed up and that is exactly what I am having after a few exceptionally cold weeks.
Now, I have a few questions and appreciate your input before I go ahead and remove it :

1- Where this mysterious device is located exactly? I know it is on the outside of the IP, but I found no mention of its exact location in the manual nor there was any pictures/drawings. Does anyone have a pic of it to help locate it?
2- Before removing it, is there a way to bypass it to confirm it is cause of the problem. Is there some sort of lever or linkage that can be removed to disable its action temporarily?
3- I read that the blanking plate and other ancillaries are interchangeable with some bits from Volkswagen. Any part numbers available so I can get them from any VW dealer/supplier here?

I did a search on the forum here and found some instructions on how to remove it but didn't seem to find answers to my questions above.. Thanks ....

:cheers:
 
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Re: my previous post about RPM increase
https://forum.ih8mud.com/diesel-tech-24-volts-systems/261832-unexplained-increase-rpm.html

The ACSD seems to be the likely culprit. I have done a bit more diggin and it seems that when the thermal wax inside the ACSD fails, it retains the high RPM and the timing advance even after the engine is fully warmed up and that is exactly what I am having after a few exceptionally cold weeks.
Now, I have a few questions and appreciate your input before I go ahead and remove it :

1- Where this mysterious device is located exactly? I know it is on the outside of the IP, but I found no mention of its exact location in the manual nor there was any pictures/drawings. Does anyone have a pic of it to help locate it?
This is a piccy of the 1HD-FT but the 1HD-T is the same. It's the thermo wax assy in this drawing.

ACSD.jpg


2- Before removing it, is there a way to bypass it to confirm it is cause of the problem. Is there some sort of lever or linkage that can be removed to disable its action temporarily?
Not that I know of.

3- I read that the blanking plate and other ancillaries are interchangeable with some bits from Volkswagen. Any part numbers available so I can get them from any VW dealer/supplier here?
It wouldn't surprise me if most Bosch and NipponDenso (Zexel too?) VE pumps will use the same blanking plates.
 
to the ACSD and from to the block there are 2 by pass water hoses that let the ACSD know when the engine are already warmed ..

If you gonna replace with backin place .. you need to run plugs on the block for those hoses ..

Did you already hech you got water flow on those hoses .. ?
 
to the ACSD and from to the block there are 2 by pass water hoses that let the ACSD know when the engine are already warmed ..

If you gonna replace with backin place .. you need to run plugs on the block for those hoses ..

Did you already hech you got water flow on those hoses .. ?

No, I didn't check, but maybe I should...That's a good point..
If I am to blank off the ACSD, I assume I should just join the two hoses together, no?
Any idea what ID (or OD) are they so I can buy the appropriate fitting beforehand?

Still trying to source the blanking kit. I phone around some Bosch dealers and they will get back to me. Hope they can get them..
I don't know the VW part numbers otherwise I would have stopped by the local dealer to check their stock.

Thanks for your help..
 
l made my own using 1/8" steel.
Simon
Winnipeg
 
I just did this yesterday

You need to remove the trans kickdown cable bracket first to give yourself some room.
Remove the ACSD by taking out the three allen screws.
Remove the coolant hoses and just plumb them together 3/8 union splicer works
Be ready to plumb the hoses together when you take them off because they just keep running fluid.
Also when you remove the ACSD quite a bit of diesel comes out of the ip.
You do not need to buy a blanking plate. Very easy to make. Just use a 3/16 thick piece of aluminun.
Now use the ACSD for a template for the 2 holes that attach the plate to the ip. Just back drill through the ACSD and aluminum. The longer hex screw is not used again, just the 2 shorter ones.
Now cut out the shape of the blanking plate large enough to cover the o-ring that was removed with the ACSD. This O-ring is reused. Cut the aluminum plate with a band saw or hack saw and file to finish.
Be sure the holes in the new plate are debured. The plate must be flat for the o-ring to seat properly.
Put it all back together and remember to pump some diesel with hand pump into the ip. You may need to adjust the idle set screw after this.

Hope this helps
My engine idles better and runs smoother after this mod.

Frank Probst
 
Thanks Frank/Simon..
Good to know that it can be manufactured easily. I guess that's what I will do..
Cheers,
 
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Thanks Frank/Simon..
Good to know that it can be manufactured easily. I guess that's what I will do..
Cheers,

They are easy to make ,but any diesel shop will have them lying about. They all appear to be the same size.
POWER LINE PICS 024 (Medium).jpg
 
Update:
Had the ACSD removed today. RPM went back to normal after being abnormally high.. The blanking plate was off an old Bosch pump, these things seem pretty common to all IP..
Thanks to all who helped me out through this. One less thing to worry about after removing it..

Cheers,
 
Glad you've had a good outcome. :)

Is it worth pursuing getting the ACSD working properly?. I would have thought anything that helps start+idle when cold would be a good thing in CAN. My ACSD does not move as much as it used to but even in the [relatively] mild (~ -5C) winters I get, I find it useful as I'm not playing with the hand throttle as much.
 
Glad you've had a good outcome. :)

Is it worth pursuing getting the ACSD working properly?. I would have thought anything that helps start+idle when cold would be a good thing in CAN. My ACSD does not move as much as it used to but even in the [relatively] mild (~ -5C) winters I get, I find it useful as I'm not playing with the hand throttle as much.

I am sure it is there for a reason, and frankly I am a bit worried about starting in the cold weather here after removing it, but as far as I know, the manual choke should do the same thing. I had absolutely no problems starting the truck down to -25 DEGC and that made quite happy as I was really worried, but let's see what'll happen after it has been extracted.

So far, the truck idles and drives great. I feel full control over the throttle now unlike before when it was high for no obvious reason. I read some posts from fellow Calgarians here who removed the device and they did not report any problems. I'll keep my fingers crosses..
 
very good info.
If anyone can offer some dimensions or part number for the plate, that would sure be helpful.
Otherwise I guess that the DIY out of aluminum is a good plan. No worries about galvanic corrosion with the IP or anything like that?

I'm also looking at that water line to run my Veggio oil heat exchanger. Hmmm.
 
very good info.
If anyone can offer some dimensions or part number for the plate, that would sure be helpful.
Otherwise I guess that the DIY out of aluminum is a good plan. No worries about galvanic corrosion with the IP or anything like that?

I'm also looking at that water line to run my Veggio oil heat exchanger. Hmmm.


These plates can be found on most any VW Bosch pump. If you have a local diesel shop with scrap VW pumps they'll have the plates.
 

That's a great write-up.. Thanks for posting/sharing it..

Wish I saw it before I get this job done. I didn't really know a part number for the plate, I just phone a Diesel shop here and told them the problem and the guy prepared a "kit" for me. I was skeptical that he may not bother replying my call for a 20$ set of parts but he did actually and I even let them do the removal job since it has been brutally cold around here recently and my garage is not heated..
 
can someone make some simple measurements for me?
maybe: distance from hole to hole. or just total width x total length?

I'm going to stop in at a diesel shop tomorrow and try to find one, but it might be real helpful to have a measurement.

thanks
 
can someone make some simple measurements for me?
maybe: distance from hole to hole. or just total width x total length?

I'm going to stop in at a diesel shop tomorrow and try to find one, but it might be real helpful to have a measurement.

thanks

Sorry Sandcruiser, I do not have a measurement for you. I had the shop source and install the plate. But, I suggest that you print out the drawing(s) in the replies above and take them with you to the diesel shop so that they understand what I was talking about.
However, when I called and mentioned the Cold Start Device the tech knew what I was talking about.
 
I think it's common enough, that most Denso IP have the same dimensions. When I got mine, I simply asked for a block off plate for a Denso injection pump (and new o-ring).
 
I'll just hope for the best :)
 

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