- Thread starter
- #21
Ah okay. I'll edit it back out in the meantime....
Leaky injector, now injector swap & manifold cleaning
- Thread starter Spook50
- Start date
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- Thread starter
- #23
Thanks Onur. I put it in the parts list post.
- Thread starter
- #24
Well a couple weekends ago I finally got the job done and I must say my 62 is running WAY stronger than before, and much more smoothly. I've been driving it around since then, getting the throttle and cruise control cables adjusted just right, had to change out the bad TPS on the "new" throttle body for the known good one from the TB that I had removed, and making sure everything is dialed in.
First things first: the freshly cleaned, refurbished and flow match injectors. On the left is how they come back from Injector RX, the right is with the spacer, its O-ring and the vibration damper installed and ready for install onto the engine. Being ~36 year-old injectors that I had serviced, there were a few bits of minor surface corrosion on the metal bodies that I got mostly cleaned up with some 0000 steel wool and a little Naval Jelly, then wiped off with a damp rag.
All six prepped and ready to go...
Before diving in, I remembered I have a spare plenum ("surge tank" per Toyota's nomenclature), so in an effort to save downtime for the job, I stripped it down and cleaned it up as best I could using a very redneck DIY hot tank setup.
The surge tank stripped down and ready to be dunked. You can't see in the pic but I also punched out the plugs on each end of the main body to allow the cleaner to flow through better as I dunked it and had it boil.
My 55 gallon drum set up on some landscape stones with a propane burner from a turkey fryer underneath. Given how somewhat precarious this setup was, I was careful to use the bare minimum of liquid in the barrel (so as to minimize the potential for toppling over and spilling), and made sure to use a cleaner what was not caustic in case there was a spill. Luckily, no spills and it went very well. Now that the hot tanking shenanigans are done, the barrel is destined to be a smokeless fire pit to take to my friend's mountain cottage in central WA.
The cleaner I used. I wanted to use something that would be fairly easy on aluminum while still aggressive on carbon and oil deposits (of which there was VERY thick stuff in the surge tank from years of a functioning EGR and stock PCV system). I used the entire gallon along with 14 gallons of water and it just covered the surge tank when lowered into the barrel. Another reason I wanted to use as little liquid as I could was because I wanted it to maintain an aggressive boil with the lid placed over the top of the barrel.
First things first: the freshly cleaned, refurbished and flow match injectors. On the left is how they come back from Injector RX, the right is with the spacer, its O-ring and the vibration damper installed and ready for install onto the engine. Being ~36 year-old injectors that I had serviced, there were a few bits of minor surface corrosion on the metal bodies that I got mostly cleaned up with some 0000 steel wool and a little Naval Jelly, then wiped off with a damp rag.
All six prepped and ready to go...
Before diving in, I remembered I have a spare plenum ("surge tank" per Toyota's nomenclature), so in an effort to save downtime for the job, I stripped it down and cleaned it up as best I could using a very redneck DIY hot tank setup.
The surge tank stripped down and ready to be dunked. You can't see in the pic but I also punched out the plugs on each end of the main body to allow the cleaner to flow through better as I dunked it and had it boil.
My 55 gallon drum set up on some landscape stones with a propane burner from a turkey fryer underneath. Given how somewhat precarious this setup was, I was careful to use the bare minimum of liquid in the barrel (so as to minimize the potential for toppling over and spilling), and made sure to use a cleaner what was not caustic in case there was a spill. Luckily, no spills and it went very well. Now that the hot tanking shenanigans are done, the barrel is destined to be a smokeless fire pit to take to my friend's mountain cottage in central WA.
The cleaner I used. I wanted to use something that would be fairly easy on aluminum while still aggressive on carbon and oil deposits (of which there was VERY thick stuff in the surge tank from years of a functioning EGR and stock PCV system). I used the entire gallon along with 14 gallons of water and it just covered the surge tank when lowered into the barrel. Another reason I wanted to use as little liquid as I could was because I wanted it to maintain an aggressive boil with the lid placed over the top of the barrel.
- Thread starter
- #25
And after a few hours of boiling with periodic removals to scrub at the heavier deposits. She's all clean! For some reason the dust that was left on the outside (actual dirt/dust, not oxidation) brushed off very easily so I took care of that and then utilized a benefit of being happily divorced: Ran that sucker through the dishwasher on a pots & pans cycle with high temp sanitary rinse 
Since I was going to have everything apart, I decided to go ahead and send the spare throttle body to RC Fuel Injection to have it bored out. From the factory, the point where the throttle body meets the surge tank is 70.5mm on both the TB and the surge tank. When I got the TB back, I measured it at 73mm. I think one reason boring out the 3FE TB is considered a waste is the fact that no matter how big it is, if the inlet of the surge tank is still only 70.5mm, that's what you're still stuck with. So I took the time and used my Dremel to slowly remove material all around the inlet until it perfectly matched the TB and Fel-Pro gasket I had ready to go (thanks again @cruisermatt ). What's interesting is the Fel-Pro TB gasket already had a 73mm cut for the opening.
Throttle body wide open to see the enlarged opening and only minor staining left inside the surge tank. Also notice that the throttle plate pivot is a flat profile unlike the solid round pivot on an unmodified TB.
And just for giggles, the fancy new throttle plate that RC installed.
Since I was going to have everything apart, I decided to go ahead and send the spare throttle body to RC Fuel Injection to have it bored out. From the factory, the point where the throttle body meets the surge tank is 70.5mm on both the TB and the surge tank. When I got the TB back, I measured it at 73mm. I think one reason boring out the 3FE TB is considered a waste is the fact that no matter how big it is, if the inlet of the surge tank is still only 70.5mm, that's what you're still stuck with. So I took the time and used my Dremel to slowly remove material all around the inlet until it perfectly matched the TB and Fel-Pro gasket I had ready to go (thanks again @cruisermatt ). What's interesting is the Fel-Pro TB gasket already had a 73mm cut for the opening.
Throttle body wide open to see the enlarged opening and only minor staining left inside the surge tank. Also notice that the throttle plate pivot is a flat profile unlike the solid round pivot on an unmodified TB.
And just for giggles, the fancy new throttle plate that RC installed.
- Thread starter
- #26
Now I was ready to start on the job itself. I dove in as soon as I got home from work that Friday afternoon.
36 years of grime and dirt buildup. Notice the forward exhaust manifold heat shield. I had pulled it off one afternoon while still waiting on parts and messed around with cleaning it. I would've loved to have all three heat shields nickel plated but that would've just been more for cosmetics, and functionally a waste of money.
My hands were utterly foul as I was taking it apart, so I didn't take any pictures of that process, but suffice to say it is most definitely a chore. I doused all the manifold (and exhaust manifold downpipe flange) hardware with Mouse Milk before touching anything else, and went to town working my way up to that point. Once I got to the downpipes and manifolds themselves, it was a big grunt to get the flange nuts off after having never touched them for 36 years or service. I wish I would've used my Milwaukee 1/2" impact, but I was without a spare vehicle and couldn't go out to get a long enough extension to reach the nuts with the impact socket. I eventually got them off though and removed the entire front section of my exhaust. I wanted to buzz a few pinhole leaks closed on some of the weld joints while it was off so I took care of that after I lost daylight on Saturday. Shockingly, I didn't have a single fastener snap on me while taking the manifolds off the cylinder head. something very strange though was the the rear-most bolt had been messed with at some point in the truck's life early on and had snapped, including another towards the front that was completely missing. I chased out all the threaded holes with my rethreading set and got ready to tackle the boken bolt that was now exposed, with the manifolds finally removed. For some dumb reason I got my fingers on it and gave it a twist (don't ask me why I did that. I couldn't tell you), and the damn thing twisted right out with only my fingers! I couldn't believe my luck on that one. Better yet, all my (original!) injector connectors on the wiring harness side were in great condition and still pliable enough to leave in place! I couldn't believe that. So before pulling anything else apart I doused them all with the plastic-safe CRC Contact Cleaner to get them nice and clean. Eventually I got everything stripped down to the cylinder head and was ready to prep for installation of the new stuff.
Also decided to check my valves. Only a couple needed adjustment so they're all good yet again. Man it's so easy to get to them all with EVERYTHING out of the way
New studs threaded in and just snugged down with the new Remflex manifold gasket in place. Something that came in quite handy for me is here you can see the two lower studs. From the factory those would be M12 bolts, P/N 90119-12069 which are NLA. The location is still very easy to simply use two extra 90116-10150 studs with 90201-12004 washers and 90170-12211 nuts. The eight other bolt locations are for M10 bolts that, since I'm using a Remflex gasket that calls for considerably less torque (22 ft-lbs versus IIRC 34 or 37 ft-lbs), I was able to get away with reusing. However, if I had decided to use an OEM gasket and Toyota's torque values, I would've used new bolts which are still available from Toyota.
Before reinstalling the intake manifold (lower half) I decided to strip it down and give it a dunk as well. What's interesting is how shiny it came out compared the aluminum surge tank. The degree of shine and still light weight of the intake has me thinking that these parts are actually magnesium, which honestly would make sense, given it's in much closer proximity to the hot exhaust leaving the cylinder head than the metal of the surge tank.
Clean, studs reinstalled, and ready for reinstallation.
Intake and exhaust manifolds reinstalled (notice the fuel rail spacers already placed on the mounting studs. These are phenolic pieces and I could've easily just cleaned and reused the originals had I known, but at least they're inexpensive) and secured with nice clean (ish) heat shields, and all fasteners torqued to 22 ft-lbs. Also installed new studs on the exhaust manifold flanges (removing the old ones was a bear) and used new nuts (again, only torqued to 22 ft-lbs and installed using copper anti-seize) with Remflex ring gaskets.
36 years of grime and dirt buildup. Notice the forward exhaust manifold heat shield. I had pulled it off one afternoon while still waiting on parts and messed around with cleaning it. I would've loved to have all three heat shields nickel plated but that would've just been more for cosmetics, and functionally a waste of money.
My hands were utterly foul as I was taking it apart, so I didn't take any pictures of that process, but suffice to say it is most definitely a chore. I doused all the manifold (and exhaust manifold downpipe flange) hardware with Mouse Milk before touching anything else, and went to town working my way up to that point. Once I got to the downpipes and manifolds themselves, it was a big grunt to get the flange nuts off after having never touched them for 36 years or service. I wish I would've used my Milwaukee 1/2" impact, but I was without a spare vehicle and couldn't go out to get a long enough extension to reach the nuts with the impact socket. I eventually got them off though and removed the entire front section of my exhaust. I wanted to buzz a few pinhole leaks closed on some of the weld joints while it was off so I took care of that after I lost daylight on Saturday. Shockingly, I didn't have a single fastener snap on me while taking the manifolds off the cylinder head. something very strange though was the the rear-most bolt had been messed with at some point in the truck's life early on and had snapped, including another towards the front that was completely missing. I chased out all the threaded holes with my rethreading set and got ready to tackle the boken bolt that was now exposed, with the manifolds finally removed. For some dumb reason I got my fingers on it and gave it a twist (don't ask me why I did that. I couldn't tell you), and the damn thing twisted right out with only my fingers! I couldn't believe my luck on that one. Better yet, all my (original!) injector connectors on the wiring harness side were in great condition and still pliable enough to leave in place! I couldn't believe that. So before pulling anything else apart I doused them all with the plastic-safe CRC Contact Cleaner to get them nice and clean. Eventually I got everything stripped down to the cylinder head and was ready to prep for installation of the new stuff.
Also decided to check my valves. Only a couple needed adjustment so they're all good yet again. Man it's so easy to get to them all with EVERYTHING out of the way
New studs threaded in and just snugged down with the new Remflex manifold gasket in place. Something that came in quite handy for me is here you can see the two lower studs. From the factory those would be M12 bolts, P/N 90119-12069 which are NLA. The location is still very easy to simply use two extra 90116-10150 studs with 90201-12004 washers and 90170-12211 nuts. The eight other bolt locations are for M10 bolts that, since I'm using a Remflex gasket that calls for considerably less torque (22 ft-lbs versus IIRC 34 or 37 ft-lbs), I was able to get away with reusing. However, if I had decided to use an OEM gasket and Toyota's torque values, I would've used new bolts which are still available from Toyota.
Before reinstalling the intake manifold (lower half) I decided to strip it down and give it a dunk as well. What's interesting is how shiny it came out compared the aluminum surge tank. The degree of shine and still light weight of the intake has me thinking that these parts are actually magnesium, which honestly would make sense, given it's in much closer proximity to the hot exhaust leaving the cylinder head than the metal of the surge tank.
Clean, studs reinstalled, and ready for reinstallation.
Intake and exhaust manifolds reinstalled (notice the fuel rail spacers already placed on the mounting studs. These are phenolic pieces and I could've easily just cleaned and reused the originals had I known, but at least they're inexpensive) and secured with nice clean (ish) heat shields, and all fasteners torqued to 22 ft-lbs. Also installed new studs on the exhaust manifold flanges (removing the old ones was a bear) and used new nuts (again, only torqued to 22 ft-lbs and installed using copper anti-seize) with Remflex ring gaskets.
- Thread starter
- #27
When I first removed the surge tank, I took a look at the vacuum manifold underneath to see what I was actually still using on it. As it turned out, only one line was still being used after my desmog. This was a line coming from the forward pointing nipple on my charcoal canister's VSV and ultimately connecting to the large forward-facing nipple on the surge tank. So on the new surge tank I left the vacuum manifold off completely and ran a 6mm vacuum line directly from the VSV to the surge tank. Looks a little cleaner in there now!
When I ordered my injector service, I asked for injector O-ring grease to make installation of the injectors to the manifold and fuel rail easier. I found it funny that the grease was actually Super Lube multi purpose synthetic, which I always keep a large tube of handy. Fun fact, it's produced by Kano labs, who also makes Kroil.
So I lubricated the upper O-rings and the spacer O-rings on each injector, placed them into the intake manifold, and gently pressed the fuel rail into place over them. The FSM tells you to install them to the fuel rail first and then press the assembly into the intake manifold, but I see no plus or minus to doing it one way or the other. Manifold first and then fuel rail worked just fine for me. To ensure that no O-rings got pinched or otherwise damaged on reinstallation, the FSM tells you to give each injector a slight rotation to make sure they pivot freely once the fuel rail is secured. Each injector felt good so I was on to the rest of the job. Once everything was back together I shorted the FP and B+ terminals on the diagnostic connector, turned the key to on (without cranking the engine) and let it prime the fuel system. After a few seconds I looked around at every connection (I also replaced the pulsation dampener and the fuel pressure regulator with new parts) and sniffed all around the engine bay, find zero sign of leaks. WOOHOO FIRST ATTEMPT GOOD! I switched off the key, pulled my wire out of the diagnostic connector and closed it up, and fired up the engine. Not even one full revolution and it fired up beautifully and MUCH quieter and smoother than before. I had about half a dozen pinhole leaks that I located on my exhaust and fixed, plus with like-new injectors, good new gaskets and all valves set correctly, it felt and sounded like a completley different engine from what I was used to. I took it for a test drive and was very impressed with the noticeable increase in power. Acceleration felt much smoother and pulled much harder than before, I can upshift at lower speeds than I had before (maybe about 3-4MPH lower), bogging under heavy load is greatly reduced also. Granted I rarely bogged my engine to begin with, but on the rare occasion in stop and go traffic when I'm constantly shifting or being in too high of a gear for a speed I'm trying to accelerate from, it would still bog. That's almost eliminated now.
I was curious if the increase in power was just a placebo effect "Hey I spent money on injectors, cleaned the snot out of the entire intake system, bored out my throttle body and enlarged the surge tank inlet!" or if it was real. So I waited until last weekend's Memorial Day weekend trip to Central WA where I could put a good long run on the engine, and it is DEFINTELY far more powerful. Most long grades I no longer have to downshift from 5th to make it over and not only that but can fully maintain my speed, and the couple that I still have to downshift to make it all the way up, I make it much farther up the hill before having to drop a gear. And when I do, the 62 leaps forward. This was also with a good deal more weight than usual for the trip, in addition to my old Yakima rack and half width Rocket Box on top. Given these factors and the now confirmed extra power (rather, reovered power? I have no idea what kind of condition my old injectors were it, but they looked gnarly when I pulled them off), I still averaged 13.8 MPG for the entire trip while having the cruise control set at 75 MPH for about 80% of the drive. I'm definitely a happy camper with this job.
I went from this:
To this (pay no mind of the spring clamp on the ISC inlet hose. I secured it after taking the picture):
Now there is one caveat that I would be remiss in leaving out, and that's the fact that my idle will NOT drop lower than 850 RPM. The first thing I did to troubleshoot was to eliminate the dashpot entirely from the equation, so I backed the screw out almost entirely, so as to avoid it engaging the dashpot. There's some debate on whether the dashpot is necessary with a manual transmission, but I do think it still has benefit, as it prevents a fast transition from high throttle to idle, which can potentially lead to the engine stalling in less than optimal conditions. Back to the idle troubleshooting though, I also made sure to carefully adjust my throttle and cruise control cables to make sure that they were allowing the throttle pivot to bottom out. Next I double checked the "golden screw" to make sure I had a new, clean O-ring in place (I do), but even with the screw completely bottomed out, 850 RPM idle. Next step was to double check my TPS, as I used the one that had sat installed on my spare throttle body in the shop for years before I removed it to send the TB to be bored out. Though I adjusted it on the bench before installing the "new" TB to the surge tank, it was a bit dodgy getting it just right. So I checked it in the vehicle while chasing my high idle aaaaaaaaand, FAIL. I removed it, replaced it with the old "known good" TPS and got that adjusted perfectly with little fuss. Did this with the battery disconnected just to allow the ECU to reset. Couple days' worth of driving later and.......still rock solid (stable though) idle at 850 RPM when hot. My next step will be to bench test the idle speed control valve and make sure it's operating properly. I have an old spare so I'll check both and whichever is most accurate to the specs called out in the FSM is the one I'll use. At this point I'm using the same one that was on my engine before (and had been working fine), so I'll test both and see where that gets me. If no luck there, I'll pull the throttle body and double check the actual stop screw to make sure it's closing the throttle plate entirely. When I eyeballed it before installing the TB to the surge tank, it did look okay, but there was no sign of it having been touched by RC when they bored it out and installed the new throttle plate. I didn't want to mess with it, but I may be stuck having to at this point.
So still a little investigating to do to get my idle dialed in right where I want it, but fortunatley it's not WAY high, and other than that I'm very satisfied with how this entire job came out.
When I ordered my injector service, I asked for injector O-ring grease to make installation of the injectors to the manifold and fuel rail easier. I found it funny that the grease was actually Super Lube multi purpose synthetic, which I always keep a large tube of handy. Fun fact, it's produced by Kano labs, who also makes Kroil.
So I lubricated the upper O-rings and the spacer O-rings on each injector, placed them into the intake manifold, and gently pressed the fuel rail into place over them. The FSM tells you to install them to the fuel rail first and then press the assembly into the intake manifold, but I see no plus or minus to doing it one way or the other. Manifold first and then fuel rail worked just fine for me. To ensure that no O-rings got pinched or otherwise damaged on reinstallation, the FSM tells you to give each injector a slight rotation to make sure they pivot freely once the fuel rail is secured. Each injector felt good so I was on to the rest of the job. Once everything was back together I shorted the FP and B+ terminals on the diagnostic connector, turned the key to on (without cranking the engine) and let it prime the fuel system. After a few seconds I looked around at every connection (I also replaced the pulsation dampener and the fuel pressure regulator with new parts) and sniffed all around the engine bay, find zero sign of leaks. WOOHOO FIRST ATTEMPT GOOD! I switched off the key, pulled my wire out of the diagnostic connector and closed it up, and fired up the engine. Not even one full revolution and it fired up beautifully and MUCH quieter and smoother than before. I had about half a dozen pinhole leaks that I located on my exhaust and fixed, plus with like-new injectors, good new gaskets and all valves set correctly, it felt and sounded like a completley different engine from what I was used to. I took it for a test drive and was very impressed with the noticeable increase in power. Acceleration felt much smoother and pulled much harder than before, I can upshift at lower speeds than I had before (maybe about 3-4MPH lower), bogging under heavy load is greatly reduced also. Granted I rarely bogged my engine to begin with, but on the rare occasion in stop and go traffic when I'm constantly shifting or being in too high of a gear for a speed I'm trying to accelerate from, it would still bog. That's almost eliminated now.
I was curious if the increase in power was just a placebo effect "Hey I spent money on injectors, cleaned the snot out of the entire intake system, bored out my throttle body and enlarged the surge tank inlet!" or if it was real. So I waited until last weekend's Memorial Day weekend trip to Central WA where I could put a good long run on the engine, and it is DEFINTELY far more powerful. Most long grades I no longer have to downshift from 5th to make it over and not only that but can fully maintain my speed, and the couple that I still have to downshift to make it all the way up, I make it much farther up the hill before having to drop a gear. And when I do, the 62 leaps forward. This was also with a good deal more weight than usual for the trip, in addition to my old Yakima rack and half width Rocket Box on top. Given these factors and the now confirmed extra power (rather, reovered power? I have no idea what kind of condition my old injectors were it, but they looked gnarly when I pulled them off), I still averaged 13.8 MPG for the entire trip while having the cruise control set at 75 MPH for about 80% of the drive. I'm definitely a happy camper with this job.
I went from this:
To this (pay no mind of the spring clamp on the ISC inlet hose. I secured it after taking the picture):
Now there is one caveat that I would be remiss in leaving out, and that's the fact that my idle will NOT drop lower than 850 RPM. The first thing I did to troubleshoot was to eliminate the dashpot entirely from the equation, so I backed the screw out almost entirely, so as to avoid it engaging the dashpot. There's some debate on whether the dashpot is necessary with a manual transmission, but I do think it still has benefit, as it prevents a fast transition from high throttle to idle, which can potentially lead to the engine stalling in less than optimal conditions. Back to the idle troubleshooting though, I also made sure to carefully adjust my throttle and cruise control cables to make sure that they were allowing the throttle pivot to bottom out. Next I double checked the "golden screw" to make sure I had a new, clean O-ring in place (I do), but even with the screw completely bottomed out, 850 RPM idle. Next step was to double check my TPS, as I used the one that had sat installed on my spare throttle body in the shop for years before I removed it to send the TB to be bored out. Though I adjusted it on the bench before installing the "new" TB to the surge tank, it was a bit dodgy getting it just right. So I checked it in the vehicle while chasing my high idle aaaaaaaaand, FAIL. I removed it, replaced it with the old "known good" TPS and got that adjusted perfectly with little fuss. Did this with the battery disconnected just to allow the ECU to reset. Couple days' worth of driving later and.......still rock solid (stable though) idle at 850 RPM when hot. My next step will be to bench test the idle speed control valve and make sure it's operating properly. I have an old spare so I'll check both and whichever is most accurate to the specs called out in the FSM is the one I'll use. At this point I'm using the same one that was on my engine before (and had been working fine), so I'll test both and see where that gets me. If no luck there, I'll pull the throttle body and double check the actual stop screw to make sure it's closing the throttle plate entirely. When I eyeballed it before installing the TB to the surge tank, it did look okay, but there was no sign of it having been touched by RC when they bored it out and installed the new throttle plate. I didn't want to mess with it, but I may be stuck having to at this point.
So still a little investigating to do to get my idle dialed in right where I want it, but fortunatley it's not WAY high, and other than that I'm very satisfied with how this entire job came out.
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