Diesel Injector Cleaning DIY - Page 4 - PeachParts Mercedes-Benz Forum

charmalu · #46 07-12-2011, 11:35 AM

PNP could be a source for the shims. I see a lot of diesel engines getting scrapped along with their injectors.

Charlie

funola · #47 07-12-2011, 12:40 PM

Quote:

Originally Posted by tangofox007

Not only are shims hard to find, buying a set isn't exactly cost effective at the single car DIY level.

Don't forget you can also sand down the spring to lower pop pressure.

funola · #48 07-12-2011, 12:43 PM

Quote:

Originally Posted by RML

As long as we are talking about dentistry, I was wondering if a piece of dental floss through the hole would be effective in cleaning it? I would think that the unwaxxed stuff would work best to keep from leaving any wax in the hole.

Richard

Dental floss? What are you thinking?

How are you gonna thread that in the small hole? A brass wire of the correct diameter is the tool to use.

RML · #49 07-12-2011, 01:38 PM

Quote:

Originally Posted by funola

Dental floss? What are you thinking?

How are you gonna thread that in the small hole? A brass wire of the correct diameter is the tool to use.

Thinking outside the box.

If I had a brass wire of the correct diameter, I could push it through.

Richard

ah-kay · #50 07-12-2011, 01:48 PM

Cleaning Injector and nozzle is well within the realm of DIYers. If you have access to a pop tester then you can calibrate it accurately. I do not, so I mark it and realign it to what it was or very close to it.

My observations:

1) Scraping the nozzle with wooden or plastic sticks will not damage the nozzle. It is made of stainless steel. You need to poke it million of times to see any noticeable damages.
2) I soaked it in solvent and blew all the hole with compress air to dry.
3) You can sand it with fine grade sand paper but it may not be necessary, a cloth would wipe most dirt off.
4) The injector are held together by metal to metal contact. So there is a limit on how tight you can 'tighten' it. What I find is that the original marking is almost as tight as you can do it.
5) All the injectors I opened up have only ONE shim inside. I did not measure the thickness.
6) The spring will be weaken over time so the pop pressure may vary but can only go down. This thread's title is about 'Cleaning' DIY, not recalibration DIY. If you put it back to the same marking then the pop pressure will be close to what it was. If the spring is weaken then pop pressure will stay low.
7) I have not done it myself but you can buy feeler gauge and cut it to shim size to adjust the pop pressure. It comes in many increments so you have a lot to play with and is cheap.
8) Sanding down the spring is to lower the pressure. I would not recommend it. The spring is weaken already so shimming is the only way to increase it.

My next project is to build a pop testers but it is way down on my list. My $0.02

scottmcphee · #51 07-12-2011, 02:38 PM

Quote:

Originally Posted by tangofox007

Not only are shims hard to find, buying a set isn't exactly cost effective at the single car DIY level.

Yes, they are easy to find new, as assortment kits. For a single car, I bought a kit - they're not expensive. Mind you, they don't include all possible thicknesses. I would pick a size up and sand it down a bit to get the thickness needed, or find combinations of thinner ones and stack them.

tangofox007 · #52 07-12-2011, 03:24 PM

Quote:

Originally Posted by scottmcphee

Yes, they are easy to find new, as assortment kits.

Spark plugs are easy to find. Injector shims are not. No two ways about it.

tangofox007 · #53 07-12-2011, 03:29 PM

Quote:

Originally Posted by ah-kay

Cleaning Injector and nozzle is well within the realm of DIYers.

What is your technique for centering the nozzle in the holder during reassembly?

ah-kay · #54 07-12-2011, 03:52 PM

Quote:

Originally Posted by tangofox007

What is your technique for centering the nozzle in the holder during reassembly?

Is there any special technique? I read Jeremy post a number of times and I do not see any? Did Jeremy miss anything in the OP? Why don't you be gracious and provide the forum with tips and some insights? Please do not leave us hanging like the special tools you have or know to clean the nozzle.

ah-kay · #55 07-12-2011, 04:02 PM

Quote:

Originally Posted by tangofox007

Spark plugs are easy to find. Injector shims are not. No two ways about it.

They are a dime a dozen. Cut some feeler gauge to fit. They come in 1/1000" increment. That is what I would do in a pinch.

Jeremy5848 · #56 07-12-2011, 04:10 PM

Quote:

Originally Posted by tangofox007

What is your technique for centering the nozzle in the holder during reassembly?

FSM says nothing about "centering" the nozzle in the holder. If there is, one would want to have a fixture that could screw onto the lower body, with a relief cut out that would center the nozzle while you finished the assembly. Given the small amount of wiggle room (if any) that exists between the nozzle and the lower body, I would have to be convinced that such a thing were critical to the proper operation of the injection system.

Most folks, including me until just recently, never clean their injectors at all. My thread was intended to cover only the very basics. Nevertheless, an interesting discussion. One never knows what will be started!

Jeremy

ah-kay · #57 07-12-2011, 04:12 PM

Quote:

Originally Posted by Jeremy5848

FSM says nothing about "centering" the nozzle in the holder. If there is, one would want to have a fixture that could screw onto the lower body, with a relief cut out that would center the nozzle while you finished the assembly. Given the small amount of wiggle room (if any) that exists between the nozzle and the lower body, I would have to be convinced that such a thing were critical to the proper operation of the injection system.

Most folks, including me until just recently, never clean their injectors at all. My thread was intended to cover only the very basics. Nevertheless, an interesting discussion. One never knows what will be started!

Jeremy

Nothing personal. It is becasue James Bond is around to pick people apart but never offer any answers.

tangofox007 · #58 07-12-2011, 04:17 PM

Quote:

Originally Posted by ah-kay

Please do not leave us hanging like the special tools you have or know to clean the nozzle.

If it was as simple as you think, you wouldn't be hanging, would you?

tangofox007 · #59 07-12-2011, 04:21 PM

Quote:

Originally Posted by Jeremy5848

FSM says nothing about "centering" the nozzle in the holder.

What does the FSM say about lapping the internal parts?

ah-kay · #60 07-12-2011, 04:34 PM

Quote:

Originally Posted by tangofox007

If it was as simple as you think, you wouldn't be hanging, would you?

Very funny.

The bottom line is that if you want to supplement info then by all means do so. It does not serve any useful purposes to challenge others AND withhold info.

This will be my last post as I am adding nothing new. I give up also.