1969 280sl, fuel injectors- replace or clean?

[cattledog]

Hi there,
Can any of you comment on your experiences with having injectors cleaned or just replacing them all with new units?   Any suggestions for a reputable injector cleaning service?  I found one only that charges $20/ injector to clean and test.  New injectors are closer to $100/ea.   My SL runs a bit rich at times and I suspect the injectors are the issue.

Chris

[Rhinkel]

Hey Chris. My car sat for 20 years. I had the injectors sonic cleaned and they work perfectly after. A lot less expensive route.

[cattledog]

Thank you Rhinkel.   Does anyone have an injector cleaning service they would like to recommend?

Chris

[Jonny B]

Chris, you might want to check with Onager in San Diego. They are a Benz outfit, and may be able to assist. Also, would recommend that you have the injectors tested to see if there is a specific problem.

PS - where did you find new injectors for ~$100! that is a VERY good price.

[cattledog]

Hi Jonny
You are right, new injectors are always a bit higher than $100 each.

I found a place called Mr Injector for cleaning and testing that I may try.   Some other forums speak highly of them.

Chris

[Rhinkel]

Hey Chris

I used Injector RX in Texas. Had them back in a couple days. Can't remember what I paid but I think it was the cost of a single new injector. At the same time I blew out the lines filling them with brake cleaner then using compressed air. I worked my way backwards and then replaced the fuel line up front and the fuel filter Then blew out the fuel lines to the back- first filling them with cleaner too. Took the pump out and cleaned it out including the mesh screen filter. Then replaced the rear fuel lines and added an inline filter and cleanied the tank filter. Last I had the tank cut open, blasted, had a new metal flower pot made, coated the inside then the tank, baked it  welded it back up. 

As I said, it had been sitting 20 years. When I went to fire it up, it caught immediately and never ran so smoothly. Sediment in these systems can be disabling and I hope I never deal with a fuel delivery problem again!

Rob

[mrfatboy]

I recently tried to clean my r2 injectors with Sea Foam.  No luck.  I ended up buying new ones.

I also had called Gus am Pacific Injection and asked him about cleaning. He told me just to buy new ones as there is a very low probability that they will work correctly again.

Also another bit of info.  Years ago,  Hans at H & R told me that the early type of R1 injectors can be cleaned but the newer R2 type are highly problematic.

Which tyoe do you have?

[Shvegel]

I bought a pop tester from amazon for $130,  changed the gauge from a 5,000 PSI to a 500PSI one and did my own.  Out of 18 injectors I had 12 that would hold good residual pressure and had a good spray pattern.  Eveyone has their preference for cleaning fluid but for me Laquer thinner seems to cut the gum and varnish the best.

[cattledog]

Hi Shvegel and others,
I think sending my injectors out for cleaning and testing sounds better for me.

Potential fuel delivery issues before the injectors have me wondering though.   Would it be helpful to disconnect the fuel line from each injector and confirm fuel flows out before focusing on the injectors?

I would want to catch any fuel that comes out of the line when it is disconnected for testing.  Anyone have any tips on this kind of testing?

Chris

[MB64Coupe]

Just cleaned and tested my injectors using a tester, found 1 suspect one.  Used an ultrasonic cleaner with all sorts of different cleaners haha. Simple green, carb cleaner, lacquer thinner, diesel... Engine hadn't been run in 21 years. The tester came with a hard line that I could screw onto the injection pump. Since I don't have a small graduated cylinder to see how much gets pumped out, I weighed the container on a triple beam scale just to compare one port from another. 2 were nearly identical and the 3rd had more so I found my way too rich cylinder just weighing how much fuel came out.  Cranked the key for 15 seconds each time, not very much comes out at all.  Just as a side note, I leaned that one cylinder out and now it's really close to the other 2 I measured, engine smoothed out some too.