Fuel injectors cleaning
04-05-2013, 02:49 PM
#17
Rennlist Member
I got the injectors back. He replaced the o-rings, pirtle caps and screens. He included the old parts in a sealed plastic bag - very nice. Does that answer your question?
02-11-2014, 06:20 AM
#18
Nordschleife Master
Everyplace does about the same, clean by placing the injectors in a heated ultrasonic chemical bath while cycling the injectors for some period of time, varies up to a few hours.
Everybody seems to use a system by ASNU, there may be some variation on chemicals used in the cleaning, with claims that some are not good for overall injector life, internal seals etc.
Some issues in the past with getting the proper oring for a Porsche 928, its not clear if that is sorted out by now or not.
Everybody seems to use a system by ASNU, there may be some variation on chemicals used in the cleaning, with claims that some are not good for overall injector life, internal seals etc.
Some issues in the past with getting the proper oring for a Porsche 928, its not clear if that is sorted out by now or not.
02-11-2014, 01:19 PM
#19
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Join Date: May 2012
Location: 88 928 S4 in Dallas, TX
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All, if anyone in N Texas wants their injectors cleaned, please consider me. I have a professional injector cleaning machine right here and will be happy to get your business.
Most local places charge $25 per injector. I will clean them and test them for $18 per injector including replacement pintle caps and filters.
Most local places charge $25 per injector. I will clean them and test them for $18 per injector including replacement pintle caps and filters.
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MachinegunT (09-14-2023)
02-11-2014, 01:31 PM
#20
Captain Obvious
Super User
Super User
The way the cleaning shops ballance the injectors is by having a bunch in stock and matching up a set (in the 928 case 8) that have flow figures that are close to each other. So the injectors you send in might not be the ones you get back. The issue with cleaning "rebuilding" injectors is that the internal movig parts will be just as worn as they were before, except the outside will look brand new.
02-11-2014, 07:13 PM
#21
Nordschleife Master
The way the cleaning shops ballance the injectors is by having a bunch in stock and matching up a set (in the 928 case 8) that have flow figures that are close to each other. So the injectors you send in might not be the ones you get back. The issue with cleaning "rebuilding" injectors is that the internal movig parts will be just as worn as they were before, except the outside will look brand new.
With common injectors, some places may still keep some in stock to make matched sets. I see people on ebay etc that farm junk yards and clean and match sets for sale.
WH also recommends checking the resistance and only sending in sets that match within 10%.
02-12-2014, 05:01 PM
#23
Craic Head
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The way the cleaning shops ballance the injectors is by having a bunch in stock and matching up a set (in the 928 case 8) that have flow figures that are close to each other. So the injectors you send in might not be the ones you get back. The issue with cleaning "rebuilding" injectors is that the internal moving parts will be just as worn as they were before, except the outside will look brand new.
I don't think so for a 928, most injector places say do NOT store cleaned injectors as they have a high tendency to rust internally. Most I think require sending in extra injectors so a matched set can be selected. Its one of the questions I asked Witch Hunter and I am waiting on a reply, their web site says ask about matched sets.
With common injectors, some places may still keep some in stock to make matched sets. I see people on ebay etc that farm junk yards and clean and match sets for sale.
WH also recommends checking the resistance and only sending in sets that match within 10%.
With common injectors, some places may still keep some in stock to make matched sets. I see people on ebay etc that farm junk yards and clean and match sets for sale.
WH also recommends checking the resistance and only sending in sets that match within 10%.
I think it's much more common to send extras and they'll let you know which ones are closest. I should look for the link on an injector cleaner website where I read this, but I'm lazy.
Basically with 'balancing' they pick the 8 (in our case) that have the least variance between them, not the most or least flow. I have long been banging the same drum about cleaning vs. replacing though. Injectors are essentially solenoids that operate in a harsh environment. They open and close so they have moving parts. Those moving parts wear over time and the constant heat cycling can't be good for anything.
What you gain from making the outsides look nice and ensuring they seal properly on the fuel rail doesn't do anything to refurb the actual mechanical valve that opens and closes.
Just my .928...
02-12-2014, 10:17 PM
#24
I don't think so for a 928, most injector places say do NOT store cleaned injectors as they have a high tendency to rust internally. Most I think require sending in extra injectors so a matched set can be selected. Its one of the questions I asked Witch Hunter and I am waiting on a reply, their web site says ask about matched sets.
With common injectors, some places may still keep some in stock to make matched sets. I see people on ebay etc that farm junk yards and clean and match sets for sale.
WH also recommends checking the resistance and only sending in sets that match within 10%.
With common injectors, some places may still keep some in stock to make matched sets. I see people on ebay etc that farm junk yards and clean and match sets for sale.
WH also recommends checking the resistance and only sending in sets that match within 10%.
02-12-2014, 11:32 PM
#25
Nordschleife Master
Leo posted his before/after results from Witch Hunter in the Pelican thread.
Before flow varied from low of 114 to 119, only one injector looked good, flow stayed at 119, rest improved to all 119/120 except for one at 121.
Two had bad patterns combined with low flow, enough that those cylinders likely had some lean issues and detonation.
Just like an aging MAF, almost everybody could use new or cleaned injectors. Intake orings might be the first item to start failing and leaking air.
Before flow varied from low of 114 to 119, only one injector looked good, flow stayed at 119, rest improved to all 119/120 except for one at 121.
Two had bad patterns combined with low flow, enough that those cylinders likely had some lean issues and detonation.
Just like an aging MAF, almost everybody could use new or cleaned injectors. Intake orings might be the first item to start failing and leaking air.
03-28-2014, 06:28 PM
#26
Rennlist Member
Had a great experience with Cruzin Performance. I was in a time bind and Rich spent lots of time on the phone with me prior to my shipping them to him to ensure good coordination. He turned them around in less than a day. Awesome service!
03-28-2014, 11:13 PM
#28
Rennlist Member
OK this may be a stupid question. I am replacing the 8 short injector hoses on my 84 L-jet. I could send the injectors in for cleaning but am a little afraid of breaking them. I was thinking of leaving them in place while changing the hoses but injecting a few cc's of Techron into each injector. Do you think this would be good or bad?
Thanks,
Dave
Thanks,
Dave
03-28-2014, 11:57 PM
#30
Shameful Thread Killer
Rennlist Member
Rennlist Member
http://www.ebay.com/itm/Mercedes-R10...e2cfc4&vxp=mtr
I got these for my Ferrari, it's the same for the 928. Roger at 928sRUS may have them even cheaper as he buys in larger quantity.