Need help with ACSD and expertise wth injection pump

[83bj60]

Hello Folks,

I am posting this as a new thread to consolidate the posts I made in other threads, in the hope I can get some help by the experts with my fuel problem . I hope this post is not too long or hard to read, I just want to make sure I've explained everything as clearly as I can to help in diagnosis.



To sum it up, here's my story so far:

- Last year I disconnected the Thermowax of the ACSD because it was leaking coolant. I left the ACSD in place (Bad Idea, I guess!).

- Over the last months, maybe over the last year, starting has been a bit rougher when very cold, compared to when I first got the truck, but nothing abnormal. At 160,000 km, I am probably due for an injector rebuild anyway. For starting, I noticed I had to 'give it gas' for a few seconds to help it start smoothly. But just a wee tad, for maybe 10 seconds or so, and the roughness lasts no more than 2 seconds in the coldest of weather. In other words, nothing out of the ordinary (yes, double glowing seems to alleviate the slight coughing).

- For the past year or so, cold (winter cold) idle has tended to be a bit lower than it had been when I first got the truck, as low as 400 RPM for maybe 20 seconds or so, and higher when hot (as much as 900-1000). This has been a very gradual change over the past year.

- A few days ago after a fill up, I noticed that idle went all the way to just past 1000 hot for the first time. Otherwise no problems.

- Next morning when starting, I started it with a wee touch on the gas pedal as I have been doing in the past year or so, and went to the job site.

- I stayed on site 4 hours, in mild winter temperatures (-10C).

- When restarting, it coughed like mad at idle, as if I had no idle at all, and didn't relent for a good 20 minutes. Everything was normal at highway speeds. No loss of power, but with this scare, I didn't dare to push it and maintained normal highway speeds. Arrived on the job site, the idle was still rough. When I shut it down the engine ran on. I was only able to shut it off moving the truck up a slight slope in drive and on idle, then shutting it off.

- No visible evidence of any problem could be seen under the hood, and from down below.

- Stayed maybe 1/2 hour on site, then started the truck. It hesitated a wee bit at idle, then idle went back to normal after a couple of stops. went directly back home.

- Posted on ih8mud for some advice. Thought it was bad fuel, got warnings about the ACSD.

- Removed the filter, not a drop of water in the fuel that came out of it. Fuel is pristine clear. The filter medium was, however, on the brown side, so I replaced it, and using the top button on the pump housing, pumped a few strokes (is the plunger travel supposed to be so short?).

- Did not use the truck for several days, got snowed in... Finally, after reading more online about it, decided to remove the ACSD.

- Lots of pain removing some of the Aleen head screws holding the dang thing. Had to shape a large bit with concave sides to 'bite' better into the screws as one of them almost rounded off trying to remove it. Used a heat gun on the aluminum body of the pump to expand the threads a bit, helped a lot. Cost me the afternon... Not 5 minutes or an hour... That's when you are in a heated garage with all the right tools and a helper

- Disconnected The fuel line from filter housing to the pump and noticed it was bone dry. Hmmm! That doesn't seem normal. Maybe the air from the filter was pushed into the pump when I primed the filter? Where does that air go when you prime the filter?

- Finally got the ACSD off, discovered the ACSD pin was sheared off, exactly like every other one posted here. Definitely a design or manufacturing defect, from its appearance.

- Inside the cavity, there is NO visible shavings that I could see, and nothing I could remove with a strong neodymium magnet. Where did the ACSD pin go? Where are the shavings?

- Made a plate from a piece of stainless steel I had lying around and covered up the ACSD hole.


Questions:

- I can't understand, with the obvious shear visible from the ACSD device, where the missing piece went. It's not small, where could it have gone? I simply can't understand that, and cannot believe it was somehow pulverized by the pump internals. Just doesn't make sense.

- When I had the engine run-on problem I suspected the fuel cut off solenoid. Running on could be caused by temporary debris lodging between the valve and the seat. Thing is, where did it go? Back to the fuel tank?

- Would it be a good idea to spray diesel into the ACSD opening? Looking to get the crud out - I'm told there is a strainer in there - can't find it on the diagrams - Could spraying diesel through the ACSD hole dislodge shavings? Is there an access hole or part of the pump where the bad stuff can accumulate and be cleaned out without requiring a total dismantle?

- I can't find any schematics of the internals of the pump. This would help tremendously! Does anyone know where to find to get one?



In conclusion:

I am ready to assemble the rest, prime the fuel and start the engine truck. Should I be OK, or will I damage the pump more if I continue until I find a shop that can fix it? I have a contract coming up on Saturday and need my vehicle, so I can't afford to have it in the garage until then.

Thank you for your feedback, hope you can help!

 

[LanceCruiser]

I would suggest removing the plate you made for the ACSD, and put a big bucket to catch all the diesel underneath it. Use the primer on the fuel filter to flush out any metal particles, give it a few quick pumps to purge it. Check the bucket for any metal filings. If you find any, I would do it a few more times to see if more come out. There is also an overflow screw, it sit right underneath the diaphragm, and looks like a bolt that attaches a fuel line to the body. I think it's a 17mm head. Remove it, and be careful there is a crush washer to catch. When you've removed the bolt, it's hollow inside and there is a small pin hole underneath the head, where the fuel line attaches. Tap the end of it on something hard, like a handle of a wrench, to knock loose any particles of metal, that got trapped there. Blow on the end of it to see if the pin hole is not clogged either. Sorry this is the only pic I could find. I can post a pic of where it is tomorrow, if you don't find it.

 

[Squash]

Try the filter below your Fuel Shut Off Solenoid...you could remove the solenoid and filter, try pushing fuel out by cranking the engine, catching the fuel and inspecting for debris. You may even try this via compressed air???

Try a magnet once the solenoid and filter are out then fuel and or air to flush...

 

[Squash]

My Toyodiy.com site is screwing up so try this one.
TOYOTA & LEXUS Electronics Parts Catalogue

Your Part should be 22602 filter.

Hope this works.

 

[83bj60]

I would suggest removing the plate you made for the ACSD, and put a big bucket to catch all the diesel underneath it. Use the primer on the fuel filter to flush out any metal particles, give it a few quick pumps to purge it. Check the bucket for any metal filings. If you find any, I would do it a few more times to see if more come out. There is also an overflow screw, it sit right underneath the diaphragm, and looks like a bolt that attaches a fuel line to the body. I think it's a 17mm head. Remove it, and be careful there is a crush washer to catch. When you've removed the bolt, it's hollow inside and there is a small pin hole underneath the head, where the fuel line attaches. Tap the end of it on something hard, like a handle of a wrench, to knock loose any particles of metal, that got trapped there. Blow on the end of it to see if the pin hole is not clogged either. Sorry this is the only pic I could find. I can post a pic of where it is tomorrow, if you don't find it.

Thank you Man, this is a great tip! I will definitely do that. Get a bite and a coffee, and off I go to do that.

 

[83bj60]

Try the filter below your Fuel Shut Off Solenoid...you could remove the solenoid and filter, try pushing fuel out by cranking the engine, catching the fuel and inspecting for debris. You may even try this via compressed air???

Try a magnet once the solenoid and filter are out then fuel and or air to flush...

Thanks! I finally found where it is studying the FSM last night (picture below)

After carefully looking at the pump diagram (detail picture below), I am hesitant removing the strainer as it might let debris into what seems to be the most sensitive area of the pump, the pump plunger. What do you guys think?

I am contemplating removing the timer subassembly under the ACSD, though, since it's situated below (see picture below), I am assuming that if there are any metal shavings, there is a possibility they could be there.

So what do you guys think? Am I making any sense? Am I looking for trouble removing the strainer? What about the timer subassembly? Doable with the pump in situ? Advisable?

 

[Squash]

I would try to back flush using the Fuel shut off as the escape route...just need to find an open injector line.
Try fuel first and if something comes out switch to air.

Maybe a vaccum cleaner to suck the crap out while removing the filter???

 

[83bj60]

I would try to back flush using the Fuel shut off as the escape route...just need to find an open injector line.
Try fuel first and if something comes out switch to air.

Maybe a vaccum cleaner to suck the crap out while removing the filter???

Great thinking! How about removing the strainer, blocking off the piston inlet and forcing the fuel to spew out of the top of the solenoid cut off? that shut flush it out!

 

[LanceCruiser]

My diesel mechanic showed me what I posted. I haven't tried this, maybe I might do it too.

 

[83bj60]

She runs!

I spent the day, a nice day, warm, windy, removing the solenoid switch, the overflow and cleaned out the main piston inlet. There was a lot of metal powder, most of which was stopped by the strainer .

When I removed the overflow hollow nut, it was filled with fine metal powder, approximately 70% magnetic, 30% non magnetic. Flake size, less than .2mm. Cleaned it out thoroughly and put it aside.

I went on to remove the fuel cut solenoid. A bit tricky because of the constrained space. You need a professional grade, thin and narrow 8mm wrench for the contact nut, a socket won't fit.

The solenoid itself requires a 24mm wrench, I did not have one, but I managed to take it off with a lockable Wescott wrench I have, neat tool.

I immediately noticed some very fine metal powder on the plunger. Really fine stuff, that had gone through the strainer. I can very well understand now why I could not shut off the engine the other day... I went in with a pocket pen magnet, which was able to remove quite a bit of super fine powder from there.

I left the magnet, narrow enough to fit into the solenoid well but large enough to close the injection piston opening, and pulled the strainer up with a small needle nose plier. If was covered half way down with very fine gray, magnetic powder, and some larger, bright, non magnetic flakes, probably up to .5mm in size.

I noticed the fuel passage from the central part of the pump going to the injection piston inlet was perhaps 1/3 filled with fine metal powder. I removed that with a printing ink syringe, worked well. I then proceeded to empty the solenoid well dry with the syringe.

Using a piece of vinyl tubing I had lying around, approx. 3/8 external diameter, and using pipe insulation foam, I made a thin sucking tube that i could insert into the solenoid well, and got everything out, clean.

Using my magnet, which I had tipped with a bit of hot glue to make a tighter fit into the injection piston hole, while holding it in, I actuated the hand pump and flushed fuel out the the inlet to the injection piston. That expelled the rest of the debris into the well, which I removed with the syringe. The magnet picked up the magnetic powder, and again, I used the vacuum to remove the rest.

I must have repeated the operation another couple times. Eventually, there were no discernible flakes coming into the well, so I cleaned everything dry, reinstalled the cleaned strainer with its spring washer (using a dab of oil to 'stick' it on while inserting it), the solenoid switch powered on (so as to keep all the parts together - I managed to blow two fuses, it's very tight in there and easy to short the wire), then once installed, I turned it off, removed the contact nut, turned it back on to verify it was working normally, tightened the solenoid back in and went on to the overflow.

I used a small fuel hose I had lying around, inserted that tight into the overflow, into a clean bottle, flushed 2 litres into the bottle. No metal flakes were found.

So I installed the overflow pipes back on, the gas bracket, the kick-down cable, made sure everything was tight, turned the engine on, and started her up as if nothing had ever happened

I then went for a test drive, the idle was very steady, power was good, no difference in feel or operation. Went back home and here I am .

I will include some pictures of the whole process so as to be useful as an emergency for others at a later time; I must have taken approximately 150 pictures in all, they need to be processed, cleaned out and a sold article needs to be written. Please be patient, it will have to wait, as I have much work backed up because of this adventure. probably sometime next week, I'll have to see how put all this in (after cleaning all the pictures I have 43 left that picture the whole process, with sound annotations that, most of them macro and super macro shots, all will be hosted on an outside server).

I did find the broken part of the ACSD lever under the truck, it had fallen off when I first removed the ACSD, and I can confirm my first impression. I broke not because of wear, but because of a design defect. take a look for yourself... here is a picture of the inside of the thermowax-ACSD, look at the copper color break,

and here is a look at the broken off cam part that was inside the pump:

I am definitely NOT going to ever put an ACSD back into that pump unless I am sure the design has been improved. It's just too weak and certainly not worth the hassle. On the other hand, kudos for installing a strainer. That is probably why the pump is still functioning.

I am going to use the truck normally and will monitor the situation over the next few days. This job is obviously very experimental, I have no idea how much metal powder is still in there. I intend to remove the solenoid switch and strainer again in a week or so to check if more powder has accumulated. I will also monitor my fuel consumption, to see whether damage to the timing piston (affecting timing advance) and cam plate (affecting injection timing) has occurred; preliminary seat-of-the pants tests would seem to indicate nothing much has changed. We'll see... I'll keep you posted.

Thanks to Lance, Mike, the others who chimed in and all the people who posted their experience up online. You were of great help

 

[83bj60]

My diesel mechanic showed me what I posted. I haven't tried this, maybe I might do it too.

The vacuum idea idea worked beautifully. I have some pictures ready, next week, after I've caught up on my work, I'll post a small photo tutorial type post on how I got the metal powder out without getting it into the distributor piston. But first, I'll remove the overflow and the solenoid again to check if more metal flakes accumulated there

Running today on the highway at high speed, the truck worked beautifully. I even pushed it into ticket danger zone (above 120) for a few seconds, no problem at all. It idles well, about 750 RPM warm, and very regular. Now that she's passed her 'kidney stone', she purrs

It's certainly not over, I'll keep watching. One thing I've been noticing in the past few months, for example, is that if I'm in neutral coasting and apply the brakes, I notice the the idle increase slightly to 850 for a few seconds, so there still are things to look into

 

[LanceCruiser]

I'm glad everything worked out for you, looking forward to the pics. The fuel cut solenoid valve, I wonder if that's the reason my truck shudders and clacks on shut off?

 

[Squash]

Good work...glad you were able to think out of the box!

 

[83bj60]

I'm glad everything worked out for you, looking forward to the pics. The fuel cut solenoid valve, I wonder if that's the reason my truck shudders and clacks on shut off?

Quite possible indeed, if it continues a bit it could be leaking so to speak, if the tip is clogged with metal shavings or if it is worn out, as it's made of some sort of rubber, check it out how it looked like when I removed mine from the pump:

......

Ah well, I might as well show you how I did it now, since I already have all the pictures uploaded... Won't be the first time I get to a job sleep deprived


So... to make sure not to let any junk get into the piston inlet, I inserted my pen magnet into the inlet, where the solenoid was, to catch any metal powder, then pulled the strainer gently up and through the pen magnet:

There were a LOT of metal shavings in there, fortunately the strainer let only the finest stuff go through:

while retaining much larger pieces on the outside, any of those large flakes would have surely clogged the distribution and/or the injectors...

And look at what remained in the piston inlet well after I had removed the strainer (notice the the vacuum hose at the ready) :

This is how I adapted a 1/2" OD vinyl tube to a standard vacuum:

It worked beautifully as you can see:

Of course, I had to repeat that a couple of times, filling the pump again and forcing fuel out the solenoid inlet (check out the remaining metal flakes in this picture, on the right side of the magnet shaft):

... until the fuel came out perfectly clear.

 

[83bj60]

Good work...glad you were able to think out of the box!

I tend to do that But to be honest, without the ideas I got from you guys and the reading I did over the last week on the operation of the injection pump depicting the fuel flow (it's a Bosch VE clone), I would probably not have felt confident to do it.

You will notice the fuel flows through the timer piston (little risk of having metal bugger up the mechanism), and that it all goes out the distribution inlet at the solenoid shut off valve, so any powder ends up at the strainer (there is none on this diagram, I'm very happy there is one in actuality ):

Also, I got lucky that the ACSD internal cam somehow stayed on the outside and did not get sucked into the cam and roller arrangement. And I only found that while looking for a dropped washer: it had fallen off when I removed the ACSD. THAT gave me the confidence to close it all up after cleaning and actually start the engine

Furthermore, if you look at the ACSD cam, it was still largely intact, with no missing pieces, showing only rub or file-type marks that explained what I found in the pump:

Also, when you look at the timing cam and roller, there was little wear damage. Notice how most of the roller surface shows little damage and only minimal, localized surface groves:

It seemed the ACSD cam rubbed mostly on the outside of the timing holder, causing little functional damage:

So thank you again for your input and your encouragement. That helped tremendously!

 

[Tapage]

outstanding job and write up.. thanks for sharing it .

 

[djsherif]

Wow, glad your pump didn't die on you like mine. Great write up.

 

[83bj60]

dj, we're going to have to meet sometime and talk shop, I'm in MTL every other week or so, you're the closest JDM cruiserhead around, not many others in QC!

 

[djsherif]

Lets do that definitely, let me know your schedule in advance and we'll arrange it.

 

[LanceCruiser]

Great pics and write up, thanks. It gives me something else to look into.