M104 Fuel Injectors

[glenmore]

Can fuel injectors be cleaned by a professional shop and reused? Or best just to toss them and put in new ones? Car is a 1991 300CE with 143m. I only have records back to 87m, so they might be original to the car. Can anyone suggest a shop in the Los Angeles area if cleaning is a possibility?

Thanks,

glenmore
1991 300CE
2000 C280
1990 LS400

[deanyel]

104 motor injectors are not all the same. The HFM injector are 3 or 4 times more expensive than the CIS injectors like yours, so the argument to refurbish rather than replace is stronger. A place like this http://www.cruzinperformance.com/fuelinj.html will clean, refurbish and test injectors for $14 each. Injectors can also be cleaned in an ultrasonic machine such as at a jewelry repair shop. You might want to try a search on injector cleaning.

[Arthur Dalton]

>> ultrasonic machine >>


..I use Gumout carb cleaner in the uktra-sonic...

[A264172]

Originally Posted by Arthur Dalton

>> ultrasonic machine >>


..I use Gumout carb cleaner in the uktra-sonic...

What type of machine and how much do they run?

Is it cost prohibitive for a DIYer?

[Arthur Dalton]

Ultra-sonic bath.....
They are cheap..any drug store..used for cleaning jewelry/rings and stuff.

I have one from a medical lab [ cuz a friend works there] that is stainless steel, so all the better if you find one of them

[A264172]

Thanks Arthur.

Here's some more general FI cleaning info.
http://www.aa1car.com/library/2003/ic30336.htm

[Arthur Dalton]

Originally Posted by A264172

Thanks Arthur.

Here's some more general FI cleaning info.
http://www.aa1car.com/library/2003/ic30336.htm

Notice there reference to ultra-sonic..

>>>and most machines have an ultrasonic bath that can be used to soak badly clogged injectors. >>>

[deanyel]

Originally Posted by Arthur Dalton

>> ultrasonic machine >>


..I use Gumout carb cleaner in the uktra-sonic...

I always wondered if that would explode, nice to know that it doesn't, or at least that it hasn't yet. My guy uses regular dish soap.

I am going to use these guys for the injectors in my Eldorado. Even though my local mechanic claims to rebuild injectors, he doesn't own a ultrasonic machine or a flow bench.

http://www.witchhunter.com/index.php4

Originally Posted by deanyel

I always wondered if that would explode, nice to know that it doesn't, or at least that it hasn't yet. My guy uses regular dish soap.

It can, if the mixture is heated to near it's flash point, and some carb cleaners have a very low flash point.

[Kestas]

We discussed this before: http://www.peachparts.com/shopforum/showthread.php?t=142193

I use ultrasonic cleaners with solvent daily in my work. The only danger is if you leave the ultrasonic bath agitating with solvent and you walk away and forget about it (easy to do). For normal, attentive use there's no fire danger.

[A264172]

Originally Posted by Kestas

We discussed this before: http://www.peachparts.com/shopforum/showthread.php?t=142193

I use ultrasonic cleaners with solvent daily in my work. The only danger is if you leave the ultrasonic bath agitating with solvent and you walk away and forget about it (easy to do). For normal, attentive use there's no fire danger.

I'd be interested in hearing more about the beaker of solvent containing the part you describe in that other thread.

Is it a glass beaker that holds the solvent and the part in the tank which contains water? And is there any added saftey or is it just to conserve solvent?

[Kestas]

It's mainly to conserve solvent. My samples are small and the ultrasonic bath is big. It also allows me to more easily switch solvents as needed for my routine lab work. Yes, it's a glass beaker.

As I mentioned, the caveat with using these baths for a prolonged time is that the solvent can get hot. More than once I've left something sonicating for over an hour in alcohol. When I came back, the solvent got rather warm! I imagine leaving it for more than two hours may get it hot enough to ignite, but thankfully I can't speak from experience. Therein lies the danger. So regular, attentive use will not pose a fire danger. It's only a danger if it's completely forgotten.

I've also used the bath to clean injectors. We have a success story where one of my technicians got 8 injectors from a junkyard for one of his home projects. None of them worked, they wouldn't spritz. After I showed him how to sonicate and reverse flush the injectors, all of them worked beautifully. We used denatured alcohol for the bath (don't use methanol!) To reverse flush, we attached a length of clear hose over the nozzle end of the injector, fill the hose with alcohol, turn the sonicator on, apply ~5v (use a variable voltage source, not battery voltage) to open the injector, and blow the fluid through. Some rather nasty stuff came out of the other end.