[KClemente]

For those of you that have read my previous thread on fixing an ovaled our injector port, I have found a seemingly working fix

I contemplated on using a diesel injector crush washer from the BMW diesels, but wanted to try one more thing before giving the dealership $16 for one seal!

I bought a copper washer set from harbor freight for $7 and used a 5/16" copper washer, along with some teflon on the top part of the injector.

So far it's holding up under light boost and map 8 on jb4! A normal teflon seal would've blown by now on my motor.

Special thanks to feuer for the idea of using a crush washer on the injector port.

[Nordic335M3]

Thx for the update.

The diesel washers can be found for pennies, dont get them from bmw stealership.

I was wondering if the washer could interfere with the injector tip being correctly positioned in the cylinder?

is that teflon tape looking gnarly on there?

[N54Society]

For those of us that aren't familiar with the problem, how does one get in this situation to begin with?

Thanks

[feuer]

Originally Posted by vbp6us

For those of us that aren't familiar with the problem, how does one get in this situation to begin with?

Thanks

Improper injector installation.

[AU-bmw335i]

Originally Posted by feuer

Improper injector installation.

Can you elaborate on that? I am about to replace my injectors and would like to avoid this. I have watched/read many guides but can't have too much information....

[feuer]

Originally Posted by AU-bmw335i

Can you elaborate on that? I am about to replace my injectors and would like to avoid this. I have watched/read many guides but can't have too much information....

Installing injectors without decoupler, installing injectors with old Teflon seal, fastening the bracket up side down, ignoring misfires, ignoring oil leaks, and wiggling injectors out.

[AU-bmw335i]

Originally Posted by feuer

Installing injectors without decoupler, installing injectors with old Teflon seal, fastening the bracket up side down, ignoring misfires, ignoring oil leaks, and wiggling injectors out.

Awesome thanks. Will avoid all of the above

[KClemente]

Originally Posted by AU-bmw335i

Awesome thanks. Will avoid all of the above

Do avoid all those haha. In my case, it was the people that last did an injector job before me that installed EVERY single bracket upside down.

With a .001" rod bearing clearance, it's not hard to believe that the injector ports also have a tight clearance...

Thinking about it, that's probably also why the valve cover tells you not to work on the fuel system until the car is fully cold. Warm aluminum head is easier to oval than a cold one.

[Nordic335M3]

Originally Posted by KClemente

For those of you that have read my previous thread on fixing an ovaled our injector port, I have found a seemingly working fix

I contemplated on using a diesel injector crush washer from the BMW diesels, but wanted to try one more thing before giving the dealership $16 for one seal!

I bought a copper washer set from harbor freight for $7 and used a 5/16" copper washer, along with some teflon on the top part of the injector.

So far it's holding up under light boost and map 8 on jb4! A normal teflon seal would've blown by now on my motor.

Special thanks to feuer for the idea of using a crush washer on the injector port.

did you have to tap on the injector to get it to seat properly with the washer on there?... or is it just the bracket pushing it down

[KClemente]

Originally Posted by Nordic335M3

did you have to tap on the injector to get it to seat properly with the washer on there?... or is it just the bracket pushing it down

I had to press it down fairly hard because the teflon tape surrounding the decoupler made a tighter seal, and then the bracket put the rest of the force. Injector does not wobble whatsoever with the bracket installed.

[bbnks2]

Originally Posted by KClemente

With a .001" rod bearing clearance, it's not hard to believe that the injector ports also have a tight clearance...

Thinking about it, that's probably also why the valve cover tells you not to work on the fuel system until the car is fully cold. Warm aluminum head is easier to oval than a cold one.

Rod bearing clearance is .0015"

Injector ports have a tight tolerance, and get fitted with a teflon seal, to keep combustion IN the chamber LOL You would have several hundred PSI of cylinder pressure shooting out the top of the engine if the injectors aren't tight... direct injection.

BMW says not to work on the valve cover until the engine has cooled to give the fuel system a chance to de-pressurize and to prevent spilled fuel from igniting. I am sure there are other reasons too...

The cylinder head injector ports oval out when you install the injectors wrong and they are allowed to wobble around in their bore. Inejctors pulsing 2000psi+ and cylinder pressure actually jack hammers the injector up and down in the bore hole which the decoupler helps dampen. Metal/metal contact or exhaust gasses blowing by a seal can deform the bore hole. As stated: not replacing the seals, not replacing the decouplers, not tightening down the injectors properly, etc.

Those copper washers seem a bit thick. Have you tightened down an injector and then pulled it back out just to see what kind of interference fit is made? Hopefully it moulds itself well to the bore and injector creating a nice seal... Keep an eye out for the copper deforming over time and the injectors loosening back up.

I'd also look at these:https://www.summitracing.com/parts/e...EaAnmzEALw_wcB

conical crush washers. I've used them on nicked AN fittings to stop leaks. They are really thin though so may not create enough of a seal.

[KClemente]

Originally Posted by bbnks2

Rod bearing clearance is .0015"

Injector ports have a tight tolerance, and get fitted with a teflon seal, to keep combustion IN the chamber LOL You would have several hundred PSI of cylinder pressure shooting out the top of the engine if the injectors aren't tight... direct injection.

BMW says not to work on the valve cover until the engine has cooled to give the fuel system a chance to de-pressurize and to prevent spilled fuel from igniting. I am sure there are other reasons too...

The cylinder head injector ports oval out when you install the injectors wrong and they are allowed to wobble around in their bore. Inejctors pulsing 2000psi+ and cylinder pressure actually jack hammers the injector up and down in the bore hole which the decoupler helps dampen. Metal/metal contact or exhaust gasses blowing by a seal can deform the bore hole. As stated: not replacing the seals, not replacing the decouplers, not tightening down the injectors properly, etc.

Those copper washers seem a bit thick. Have you tightened down an injector and then pulled it back out just to see what kind of interference fit is made? Hopefully it moulds itself well to the bore and injector creating a nice seal... Keep an eye out for the copper deforming over time and the injectors loosening back up.

I'd also look at these:https://www.summitracing.com/parts/e...EaAnmzEALw_wcB

conical crush washers. I've used them on nicked AN fittings to stop leaks. They are really thin though so may not create enough of a seal.

Thanks for the response. I have pulled the injectors out after the cylinder had a misfire at WOT around 5500 rpm at 14 psi. I have doubled up the copper washer then which is the photo with the orange ratchet in the background. Ignore the burnt teflon. It has been replaced as well.

I have looked at dimensions of the diesel washer, and they seem to have a width of 2.5mm? Correct me if i'm wrong though. And these 5/16" copper washers have a width of about 1-1.2mm

[bbnks2]

Originally Posted by KClemente

Thanks for the response. I have pulled the injectors out after the cylinder had a misfire at WOT around 5500 rpm at 14 psi. I have doubled up the copper washer then which is the photo with the orange ratchet in the background. Ignore the burnt teflon. It has been replaced as well.

I have looked at dimensions of the diesel washer, and they seem to have a width of 2.5mm? Correct me if i'm wrong though. And these 5/16" copper washers have a width of about 1-1.2mm

The diesel washers are designed to crush FLAT not deform in a conical shape lol The injector seating surface is different. So yeah the 1-1.2mm washers would be better I'd think as they should deform more to seal the conical bore to the injector.

You can see in the pic how they deformed to take on the shape of the injector bore (conical). I would re-torque the lock-down brackets after a few hours of installing the injectors as the copper might still be moulding after the initial torque... I also see the center hole of the washer may not be tight enough...

Hopefully things work out for you using two washers... If you space the injector out any more it may not be able to spray into the cylinder. It doesn't look like you're getting a very good seal... the injector should not be blackened like that unless combustion is leaking past the copper washers.

[KClemente]

Originally Posted by bbnks2

The diesel washers are designed to crush FLAT not deform in a conical shape lol The injector seating surface is different. So yeah the 1-1.2mm washers would be better I'd think as they should deform more to seal the conical bore to the injector.

You can see in the pic how they deformed to take on the shape of the injector bore (conical). I would re-torque the lock-down brackets after a few hours of installing the injectors as the copper might still be moulding after the initial torque... I also see the center hole of the washer may not be tight enough...

Hopefully things work out for you using two washers... If you space the injector out any more it may not be able to spray into the cylinder. It doesn't look like you're getting a very good seal... the injector should not be blackened like that unless combustion is leaking past the copper washers.

Yep, looking at my photos it does look like that the center hole maybe isn't tight enough and bleeds past it, and up the top of the injector slightly. So far I am still running the double washer injector.

If this info is any useful, with the engine running, I can feel and hear a very slight tapping noise and feel from the injector. The rest of the injectors are smooth when they're running

I will pull this injector out tomorrow, and report back on how the teflon up top is doing and seeing if it's burnt or not.

[bbnks2]

Originally Posted by KClemente

Yep, looking at my photos it does look like that the center hole maybe isn't tight enough and bleeds past it, and up the top of the injector slightly. So far I am still running the double washer injector.

If this info is any useful, with the engine running, I can feel and hear a very slight tapping noise and feel from the injector. The rest of the injectors are smooth when they're running

I will pull this injector out tomorrow, and report back on how the teflon up top is doing and seeing if it's burnt or not.

I would try to find a teflon o-ring that you can use to seal the center of the copper. Something that fits tightly onto the shaft of the injector. Something like this (Dorman 8250): https://shop.advanceautoparts.com/p/...E&gclsrc=aw.ds

[feuer]

I have not done this repair on tuned n54 thus don't know if would hold up higher boost levels. It works well long term at 8-9psi.

[KClemente]

Another update:

Pulled the double washer injector after a misfire under high boost. Results are surprising. Both washers are clean INSIDE but sooty on the outside. There seems to be a very small leak on the bottom side of the injector as seen by the teflon.

It's weird that the top washer (closest to tip) has a clean rim, but the bottom washer, has carbon on the rim.

[Nordic335M3]

Originally Posted by KClemente

Another update:

Pulled the double washer injector after a misfire under high boost. Results are surprising. Both washers are clean INSIDE but sooty on the outside. There seems to be a very small leak on the bottom side of the injector as seen by the teflon.

It's weird that the top washer (closest to tip) has a clean rim, but the bottom washer, has carbon on the rim.

do you think the clean part of the washer is where the contact with the head is.. and its rubbing itself clean from the vibrating?

[Nordic335M3]

the copper washers oem: 13532247156 dosent fit btw.. there is four notches in the center hole so they dont fit our injectors...

[KClemente]

Originally Posted by Nordic335M3

the copper washers oem: 13532247156 dosent fit btw.. there is four notches in the center hole so they dont fit our injectors...

hm thanks for letting me know. maybe if you bore out that washer it'll fit?

My double crush washer method works 100% just fine as long as you don't wind it out to 6000rpm at 16 psi.

The next thing i want to try is that oem washer as it's a little thicker and wider. If that doesn't work, then i'll try using an injector sleeve as someone else on the forum has tried.

[Monstere92]

Originally Posted by feuer

Installing injectors without decoupler, installing injectors with old Teflon seal, fastening the bracket up side down, ignoring misfires, ignoring oil leaks, and wiggling injectors out.

How long has this fix been holding up ? I just ran into this same issue with injector 1.

[Monstere92]

Or would i be better off getting the copper seal?