Water injection again - PeachParts Mercedes-Benz Forum

psaboic · #1 03-26-2012, 09:58 AM

Folks, after doing some reading of recent threads and remembering a bit about how it worked from my younger days, I would really like to try to make and hook up a water injection system on my 83 300D. I have the next 6 days off of work so now would be a good time to do it

It seems like most of the homemade hookups have been done on engines other than the venerable OM617 though.

Has anyone done water injection on an OM617 (with a turbo) and would be willing to share a write up and pictures?

I could most likely figure it out from a write up alone, but as they say, a picture is worth a thousand words

ROLLGUY · #2 03-26-2012, 11:01 AM

I have been thinking about and gathering parts to do my 617 turbo. I got it figured out, and mostly installed the other day. I took photos and was going to post them, but it seems my photos got erased from my memory card. I will try to get some photos later today.
Basically, I figured out that the water injector nozzle has to be pointed at the incoming air flow from the turbo so it is atomized properly. The best (easiest) place for a nozzle is in the EGR port. However, if the nozzle is just pointing in the opening, #1 cyl will get most of the water, and not atomized. My solution was to solder a motorcycle carburetor jet on the end of a piece of 1/4" copper tubing, and bend it 90 degrees so it is facing the turbo in the center of the inlet. I bought a used WI kit made by Coolingmist on 'list for $120.00. It included the pump, boost switch, nozzle, hoses, check valve and related wiring. The only thing I did not get was the water tank (I was going to use my windshield washer tank anyway). I drilled out a brass fitting (1/4"pipe X 1/4" compression) so the copper tube would fit through the fitting. I have an intake from a '78 SD, so it does not have an EGR port. However, it has a screw plug at about the perfect spot for a 90 degree tube and nozzle. I drilled and tapped the hole for 1/4 pipe and installed my nozzle/tube assembly. I installed the hose and check valve. That is as far as I got, and plan to do the rest some evening this week. I also took an extra 617 EGR manifold to my friend that has a machine shop, so he could make me a prototype aluminum WI nozzle mounting plate that will bolt to the EGR port. He should have it done sometime this week. It is a little tricky, as the hole for the brass fitting will have to be drilled at a compound angle in order to get the 90 degree copper tube to fit correctly. When I talk to him today, I will get an update. I will also try to get some photos later....Rich

Simpler=Better · #3 03-26-2012, 01:08 PM

http://www.peachparts.com/shopforum/diesel-performance-tuning/233908-vaporised-alcohol-injection-4.html

I will have some kind of setup on my new build, I haven't decided on an intake manifold yet though.

ROLLGUY · #4 03-26-2012, 09:59 PM

I went to my machinist's place today, and he got the rough plates cut:

The carb jet and bent copper tubing:

Here is a photo of the fitting and nozzle installed in the manifold:

I tested it out, and I need to solder and re-drill the jet to a smaller size, as it has too much volume!:

SD300 · #5 03-27-2012, 03:38 AM

what is the benefit of water inj?
I have a 240d now, is much easier to do H2o inj, as it has not turbo.
TIA.

ROLLGUY · #6 03-27-2012, 10:55 AM

Quote:

Originally Posted by SD300

what is the benefit of water inj?
I have a 240d now, is much easier to do H2o inj, as it has not turbo.
TIA.

The benefits of WI are: carbon removal from combustion chambers (best thing when running WVO). On turbo equipped engines, methanol can be added to the water for increased horsepower. N/A engines do not benefit from using methanol. N/A engines are easier to equip a WI system to. The only thing needed is a 2 pump washer tank (found on many MB's with headlight wipers)or an added tank for WI water, a simple water jet (I use a patio mister nozzle or two), and a throttle activated switch. On a 240 the switch should be set to activate the pump at WOT (which is most of the time for a 240).

locry · #7 03-27-2012, 11:34 AM

hmmmm, interesting... so if i wanted to clean out my combustion chambers... can I just spray water in the intake once in a while? What are the conditions? minimum RPM? Can I use a handheld atomizer for this?

TnBob · #8 03-27-2012, 12:53 PM

I put one a few years back on a 60 Chevy 216cu inch inline 6.

My mileage initially dropped about 25% for about a week or so. Mileage started to climb as did a lessening of visible smoke.

At about the 3 to 4 week my mileage was up at least 25% over the mileage at the outset. The motor ran cooler at least according to the gauge and the lack of smoke continued.

Cost on a very simple WI for a carburetor run motor was under $5

funola · #9 03-29-2012, 09:53 PM

Quote:

Originally Posted by ROLLGUY

....................
Basically, I figured out that the water injector nozzle has to be pointed at the incoming air flow from the turbo so it is atomized properly. The best (easiest) place for a nozzle is in the EGR port. However, if the nozzle is just pointing in the opening, #1 cyl will get most of the water, and not atomized. My solution was to solder a motorcycle carburetor jet on the end of a piece of 1/4" copper tubing, and bend it 90 degrees so it is facing the turbo in the center of the inlet. ....Rich

Rich, any further progress? You have the jet pointing into the turbo outlet. What is the pressure output of the turbo (my guess is not much more than 15 psi) and the pressure output of the water? Is there any chance water can get into the turbo?

Geometry wise, is it possible to go in via the EGR port and have 5 individual jets pointing into each cylinder head inlet ( 5 x 1/8 o.d. capillary copper tubing?)

ROLLGUY · #10 03-30-2012, 12:47 AM

Quote:

Originally Posted by funola

Rich, any further progress? You have the jet pointing into the turbo outlet. What is the pressure output of the turbo (my guess is not much more than 15 psi) and the pressure output of the water? Is there any chance water can get into the turbo?

Geometry wise, is it possible to go in via the EGR port and have 5 individual jets pointing into each cylinder head inlet ( 5 x 1/8 o.d. capillary copper tubing?)

I have been busy with work, so I have not had the time to finish this project. The pump I am using is 50 PSI, so pressure is not a problem. I need to drill the jet that I soldered the other day with a very small drill (I am thinking maybe .050). I doubt that water can get to the turbo compressor wheel once the boost is over 8 pounds (boost switch setting). I could even face the jet down so the water hits the side of the manifold first. I believe that once the stream of water hits the column of air "head on", it will quickly atomize. I thought about 5 individual jets, but the single jet makes the job at least 4 times easier! (pun intended).

Diesel911 · #11 03-30-2012, 01:23 AM

Quote:

Originally Posted by ROLLGUY

I have been busy with work, so I have not had the time to finish this project. The pump I am using is 50 PSI, so pressure is not a problem. I need to drill the jet that I soldered the other day with a very small drill (I am thinking maybe .050). I doubt that water can get to the turbo compressor wheel once the boost is over 8 pounds (boost switch setting). I could even face the jet down so the water hits the side of the manifold first. I believe that once the stream of water hits the column of air "head on", it will quickly atomize. I thought about 5 individual jets, but the single jet makes the job at least 4 times easier! (pun intended).

5 small Jets would have to have extremely tiny holes; much smaller than 1 Jet would need.
Holes that tiny could get plugged and you would most likely need some filtration to prevent that.

ROLLGUY · #12 03-30-2012, 10:02 PM

Quote:

Originally Posted by Diesel911

5 small Jets would have to have extremely tiny holes; much smaller than 1 Jet would need.
Holes that tiny could get plugged and you would most likely need some filtration to prevent that.

I agree, and that is why I chose the simple single jet route. Patio mister nozzles work great for N/A engines, but the turbo requires a more complicated set up.

ROLLGUY · #13 04-13-2012, 12:09 PM

I got my 617 turbo WI system working. I need to put an override switch with LED (lets me know when the pump is activated), so I can turn off the system. I have it powered directly to the boost switch now. My first run driving the car, I noticed a large cloud of black smoke when tach'ed out the first time. After a few more hard runs, the black smoke was not evident. That would seem to tell me that it is working. I adjusted the boost switch so it would activate the pump only under the highest pressure, so it does not inject every time the car is accelerated. I also got the 2 plates from my machinist:

I had these made for my friend, and my brothers 300D (both with EGR). I will be making the injector tube and jet, and will post a photo. If this all works out well, I might have more made and sell them to others for their own WI system for a 617 turbo. I will also try to get some steel discs made to block off the EGR pipe on the exhaust manifold using the stock clamp.

Murkybenz · #14 04-13-2012, 02:35 PM

I may have posted this on a previous thread on this forum concerning water injection my apologies if you have already seen it

vegetableoildiesel.co.uk - Water Injection --- has cured my blowby..... IT IS sorted :-) - Powered by XMB

ROLLGUY · #15 04-13-2012, 04:01 PM

Quote:

Originally Posted by Jesus

The EGR port is the worst possible place, #1 cylinder will take nearly all the water under any conditions.

I would not disagree with the real Jesus, but since you are not him, I disagree with your statement. I know it works without issues. However, if there is a better place for the jet ("blank spot on the T3 outlet where a wastegate fitting would be placed"), then I am willing to try it. Please provide a photo of the spot you are talking about.