got the pictures all rounded up- made this at work a few weeks ago out of scrap
CK5
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DIY TBI injector cleaning set up that I made... eh???? eh????
- Thread starter scouthead
- Start date
had seen something similar online somewhere...
think it was worth a few hours of my life?
I had an extra gasket set for the injector pod and I had been trying to resurrect the K5 that had been sitting for about a year with califoristan's finest ethanol gas in it. In the time this truck had been sitting, that same pump gas ethanol had phase separated and done damage to several other bikes and buggies out at my desert place. one carb was almost ruined with corrosion, and several others just so fouled and gummed up that they would run at all. Its been such a major problem that it has made me question why i should even have the toys if all I do is repair, clean, and rebuild carbs all the time? Ive tried several fuel stabilizers... Startron is the best -hands down. But, I must have bought some especially bad and highly concentrated ethanol from someone along the way, because even the startron failed and the fleet of small motors was sidelined once again. AND there is something like a $1.25 of tax per gallon of this garbage fuel in CA now?! Maddening. I have found a source and now switched to 101 octane non ethanol fuel for all of the off-road toys. EXPENSIVE, but I don't see there as being a choice now.
back to the blazer and fuel injectors:
I had been having several other issues that were getting sorted out (timing problems, and possible damaged MAP sensor, and the ICT was a little out of spec.. also a couple small vacuum leaks), but also noticed the truck running rich and fuel was spattering and almost POURING out of the injectors at times... difficult to get a good picture, but I tried few videos and this was all about as good as I could capture on my phone:
I had an extra gasket set for the injector pod and I had been trying to resurrect the K5 that had been sitting for about a year with califoristan's finest ethanol gas in it. In the time this truck had been sitting, that same pump gas ethanol had phase separated and done damage to several other bikes and buggies out at my desert place. one carb was almost ruined with corrosion, and several others just so fouled and gummed up that they would run at all. Its been such a major problem that it has made me question why i should even have the toys if all I do is repair, clean, and rebuild carbs all the time? Ive tried several fuel stabilizers... Startron is the best -hands down. But, I must have bought some especially bad and highly concentrated ethanol from someone along the way, because even the startron failed and the fleet of small motors was sidelined once again. AND there is something like a $1.25 of tax per gallon of this garbage fuel in CA now?! Maddening. I have found a source and now switched to 101 octane non ethanol fuel for all of the off-road toys. EXPENSIVE, but I don't see there as being a choice now.
back to the blazer and fuel injectors:
I had been having several other issues that were getting sorted out (timing problems, and possible damaged MAP sensor, and the ICT was a little out of spec.. also a couple small vacuum leaks), but also noticed the truck running rich and fuel was spattering and almost POURING out of the injectors at times... difficult to get a good picture, but I tried few videos and this was all about as good as I could capture on my phone:
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I made a cap for the tube that is not in the photos... but was important for me not spilling stuff.
1) cap the compressor end of tube
2) fill with 50/50 mix of fresh gas and concentrated fuel injector cleaner from NAPA (the little bottle that says a few ounces should be good for a whole tank of gas)
3) remove screen cage from injector and spray it inside and out with carb/tbi cleaner
4) clamp end of hose over the outlet of the injector and was careful not to block the inlet port on the side
5) lowered the injector, with spare wiring pigtail connected into a bucket, and connected air compressor to other side of tube @ about 20psi
6) connected 24 inch alligator clipped leads to the pig tail, and got some distance from the fumes... even a 9 volt battery arcing near gas fumes worries me.
7) then did they 9 volt battery thing. one alligator clip to the negative, and tapped the other on the positive activating the injector.
I do not have an ultrasonic cleaner, so even though I've seen people claim they are necessary, this was the only thing I could come up with on a sat night. I alternated letting the injector sit for 4-5 min, and then tapping the battery a few times to flush the cleaner backward out of it... the 12-14 ounces of fluid in that tube could go through REAL QUICK if kept the injector open, And being that I'm not sure how good it is for the injector to be getting 9V off a battery like that, I opted for a few quick taps, and then let it soak a while, come back and give it a few more taps... let it soak, etc. When the fluid ran out, I took the injector back out, and started the next one.
incredible amazing injector back flushing???? or dumb and why bother?
1) cap the compressor end of tube
2) fill with 50/50 mix of fresh gas and concentrated fuel injector cleaner from NAPA (the little bottle that says a few ounces should be good for a whole tank of gas)
3) remove screen cage from injector and spray it inside and out with carb/tbi cleaner
4) clamp end of hose over the outlet of the injector and was careful not to block the inlet port on the side
5) lowered the injector, with spare wiring pigtail connected into a bucket, and connected air compressor to other side of tube @ about 20psi
6) connected 24 inch alligator clipped leads to the pig tail, and got some distance from the fumes... even a 9 volt battery arcing near gas fumes worries me.
7) then did they 9 volt battery thing. one alligator clip to the negative, and tapped the other on the positive activating the injector.
I do not have an ultrasonic cleaner, so even though I've seen people claim they are necessary, this was the only thing I could come up with on a sat night. I alternated letting the injector sit for 4-5 min, and then tapping the battery a few times to flush the cleaner backward out of it... the 12-14 ounces of fluid in that tube could go through REAL QUICK if kept the injector open, And being that I'm not sure how good it is for the injector to be getting 9V off a battery like that, I opted for a few quick taps, and then let it soak a while, come back and give it a few more taps... let it soak, etc. When the fluid ran out, I took the injector back out, and started the next one.
incredible amazing injector back flushing???? or dumb and why bother?
more pictures
I have a video of light shining through the waste cleaning solution after doing this to 3 injectors... bunch of junk and the solution was cloudy as hell. May not be able to get that uploaded and linked here today, but i will do that soon.
there was a VERY noticeable difference in spray pattern throughout the RPM range after putting the injectors back in the truck that night. How much of the "rich" condition was dirty rotten ethanol in the injectors... and how much was the rest of the issues I was sorting out? not sure. But I had the truck running like NEW later that night.
and don't nobody go blowing yourself up repeating this whole thing, but thought it was interesting anyway.
there was a VERY noticeable difference in spray pattern throughout the RPM range after putting the injectors back in the truck that night. How much of the "rich" condition was dirty rotten ethanol in the injectors... and how much was the rest of the issues I was sorting out? not sure. But I had the truck running like NEW later that night.
and don't nobody go blowing yourself up repeating this whole thing, but thought it was interesting anyway.
I've done something pretty similar. I don't know how much it cleans them, but it gives piece of mind that they have a decent pattern, and shouldn't be full of dust from sitting. It would be cooler to have a timed pulse and some graduated cylinders to measure the flow, but that's probably more important for MPFI.
yeah not full of dust- its just our gas here in CA is garbage, and the ethanol phase separates quickly. the ethanol is corrosive and eats rubber, aluminum, and corrodes steel fittings... and while its doing that, it turns into a nasty sludge that clogs everything. you are then left with a bunch of carburetors that wont work, and a tank full of gasoline that is ruined with no discernable octane rating anymore... love it. LOOOOOOOVE it. well worth the extra dollar and change in tax per gallon????
I don't know if I've heard of pressurized fuel injection systems having as many problems as carbs do, but I had several vehicles and bikes go down, some of them several times over while my k5 sat. petcocks ruined... one carb ruined... one carb rebuilt 2wice in the same year. F that.
no more pump gas in the toys.
I don't know if I've heard of pressurized fuel injection systems having as many problems as carbs do, but I had several vehicles and bikes go down, some of them several times over while my k5 sat. petcocks ruined... one carb ruined... one carb rebuilt 2wice in the same year. F that.
no more pump gas in the toys.
Yeah, the ethanol is a major problem in small engines. But then again, it's more the combination of ethanol and sitting. I'm used to annual carb cleanings on yard equipment and such and it looks like there's sand in the bowl.
in 2020 and 2021 i had multiple carbs go down with as little as 50 days between use. My 2001 honda 250ex had to get stripped down twice in 2021 (twice in the same year!) and the petcock was ruined the second time. Its a pain in the butt to strip all the plastics, and break/replace all the body fasteners...
the VW buggy hasnt been driven in 2 years now. I drained the tank, but have not gotten around to opening up the 40 IDF that is probably ruined... should just find a replacement to have in hand before trying to get that running again.
got to the point where i could not expect anything to actually work when I went to use it. all i was doing was taking things apart to fix it. I cant afford to put 101 octane in the blazer @ 25 bucks per gallon, but Im trying to make it work with the smaller stuff- otherwise i may as well just give up and sell everything, or move somewhere that doesn't have CA gas
It must be a carbed issue. My tank is vented to atmosphere on the K5, so it's not being open to atmosphere that is the problem I'm guessing, unless fuel volume helps.
Both my K5 (TPI) and my car (EFI) sat for a year and both start right up on the old ethanol.
Dad said the riding mower however, had a bit of a problem sitting over the winter. It being carbed, lends credence to the carbs being an issue. On that one I run the carb dry every time after mowing.
I wonder how much damage the ethanol is doing inside the throttle body and in my case fuel rails however.
Both my K5 (TPI) and my car (EFI) sat for a year and both start right up on the old ethanol.
Dad said the riding mower however, had a bit of a problem sitting over the winter. It being carbed, lends credence to the carbs being an issue. On that one I run the carb dry every time after mowing.
I wonder how much damage the ethanol is doing inside the throttle body and in my case fuel rails however.
I can say that the k5 started up and ran/drove... never sat for more than 3-4 weeks, and would be started/ moved... it just hada host of other problems and was only being moved for street sweeping and to make room to move other things. It had the same tank of gas in it for well over a year, but still started and would run. My guess is that the 12-14 psi from the fuel pump is enough to pump that stuff out of the injector pod and back down the return line? that probably would help keep things mixed i guess! gravity feed bikes and small engines don't have that advantage, and a vw running 2-3 psi from a FACET pump to a carb isn't much better.
I will add that to "clean" and backflush my TBI injectors, I had to remove the entire throttle body -the knob on the fuel pressure reg is too big to pull up through the back of the throttle body. I couldn't get the top of the injector pod up high enough to clear the top of the injectors either with that knob there, and it was just easier to pull the whole thing rather than to try and get all the small parts off, just so I could get fingers in there to back that knob all the way out (knob also eventually hits the MAP port tube- its tight back there) ...
With the injector pod opened up, I found the O-rings on the fuel lines were eroding away... probably as much do to age as to ethanol, but they would not have been reuseable, and needed to be replaced. there is a pocket in the casting of the injector pod where things can settle- it was full of crap and particulate, ethanol sludge and also the ethanol granulated material that develops in carbs. that stuff was probably 3/8 to 1/2 inch deep? I had to scrape it out with a screwdriver, then a few shop towels and carb cleaner. minor pitting to the aluminum in that area, just like the carbs. But other than that, the outside of the injectors, and the rest of the injector pod was super clean. Maybe just a little corrosion starting on the injectors where the plastic basket cage meets the zinc coating on the injector body, and just a thin layer of crud on the aluminum where the bottom O-ring meets the aluminum on the inside of the injector pod casting. I'm thinking that fuel pressure, and the return line circuit is able to pump most of that stuff out and back to the tank? hopefully to dissolve or make it through the pump and get stuck in the filter on its next pass?
Can't see inside the injector itself though -hard to know if any of that stuff is settling in the injector, and I WAS impressed by how much crap came out of 3 injectors with just 1/2 a bottle of injector cleaner concentrate mixed 50/50 with fresh gas. the cleaner went in clear and came out cloudy, milky, with an amber tint. there was also visible dirt and particles of things at the bottom of the pitcher I collected it all in.
That's always cool when you can see the fruits of your labor.
If I'm not mistaken, ethanol is a really good solvent. Perhaps as you mention, with fuel regularly flowing, it does a good job of flushing stuff out/keeping it in suspension. It absolutely does a number when it sits though.
I have a feeling I've been lucky thus far with the vehicles sitting this long, sooner or later I'm guessing the injectors are going to let me know they hate me.
I did have some weird black gunk backflow out of the fuel filter on the K5 last time I pulled it, and I have no idea where it came from. It was on the tank side of the filter, but it was obviously not rust or sediment.
If I'm not mistaken, ethanol is a really good solvent. Perhaps as you mention, with fuel regularly flowing, it does a good job of flushing stuff out/keeping it in suspension. It absolutely does a number when it sits though.
I have a feeling I've been lucky thus far with the vehicles sitting this long, sooner or later I'm guessing the injectors are going to let me know they hate me.
I did have some weird black gunk backflow out of the fuel filter on the K5 last time I pulled it, and I have no idea where it came from. It was on the tank side of the filter, but it was obviously not rust or sediment.
