VWDiesel.net The IDI, TDI, and mTDI source.
Engine Specific Info and Questions => IDI Engine => Topic started by: Pre95 on June 27, 2009, 03:02:54 pm
-
Also, when I swap em out do I need to worry about air in the fuel system, or is it as simple as removing the old, putting in the new? After having a hard time tuning the motor properly and finding the injectors look pretty old I figure might as well take care of as many question marks on the car as possible. Just need to torque specs and any heads up about bleeding later..
-
Torque the injectors to 51 ft lbs. make sure the shields go in the right way. attach all the hard lines but leave the injector ends a little loose until it starts, then tighten each one once it has pressure [spraying all over the place]
-
Torque the injectors to 51 ft lbs. make sure the shields go in the right way. attach all the hard lines but leave the injector ends a little loose until it starts, then tighten each one once it has pressure [spraying all over the place]
Perfect, thanks for the quick write-up! Maybe now I will be able to tune this thing properly...
-
I always tighten two injector lines and leave two loose, when I get fuel at the loose ones I tighten them and start it, the unbled ones bleed themselves pretty quick.
-
make sure to apply pressure going towards the head. if you pull, you'll most certainly break the injector boss. don't forget to add some anti seize to make it easier to remove in the future
-
Howdy Gang,
Could we use a impact gun to remove the injectors?
tighten then loosen a little at a time
I'd like to do a compression test
could we remove the glow plugs and do a compression test in the GP holes?
thanks
hank
-
make sure to apply pressure going towards the head. if you pull, you'll most certainly break the injector boss. don't forget to add some anti seize to make it easier to remove in the future
I've seen this numerous times on this forum. Please explain why. The way I see it, force is force, should not matter whether you are pushing or pulling. The only difference I see is that (if you don't brace yourself and something let go), you crash head first into the hood or go flying backwards and land on your butt. :D
-
The direction of the force is important. Yes a pound is a pound, but if the force we are talking about is put toward the weakest part of the head that is the problem.
-
make sure to apply pressure going towards the head. if you pull, you'll most certainly break the injector boss. don't forget to add some anti seize to make it easier to remove in the future
I've seen this numerous times on this forum. Please explain why. The way I see it, force is force, should not matter whether you are pushing or pulling. The only difference I see is that (if you don't brace yourself and something let go), you crash head first into the hood or go flying backwards and land on your butt. :D
Whenever you're tightening something on an angle like that, you're also creating a force trying to pivot your tool+injector assembly, balanced by the strength of the head. When you are pushing, this force is acting against the main body of the head itself, as you try to pivot the whole assembly about a point located at the tip of the injector.
When you're pulling toward yourself, away from the engine, you're still applying that pivoting force, but now it's acting on the thinner cast aluminum outer boss of the injector socket. This boss is much weaker than the main body of the head, and the force needed to break an injector free or torque it all the way down can cause cracks where the boss joins the head. Once those cracks form, boom, broken boss.
-
make sure to apply pressure going towards the head. if you pull, you'll most certainly break the injector boss. don't forget to add some anti seize to make it easier to remove in the future
I've seen this numerous times on this forum. Please explain why. The way I see it, force is force, should not matter whether you are pushing or pulling. The only difference I see is that (if you don't brace yourself and something let go), you crash head first into the hood or go flying backwards and land on your butt. :D
Whenever you're tightening something on an angle like that, you're also creating a force trying to pivot your tool+injector assembly, balanced by the strength of the head. When you are pushing, this force is acting against the main body of the head itself, as you try to pivot the whole assembly about a point located at the tip of the injector.
When you're pulling toward yourself, away from the engine, you're still applying that pivoting force, but now it's acting on the thinner cast aluminum outer boss of the injector socket. This boss is much weaker than the main body of the head, and the force needed to break an injector free or torque it all the way down can cause cracks where the boss joins the head. Once those cracks form, boom, broken boss.
Ok, that makes sense, thanks! If the head is weak then a breaker bar is the wrong tool to use. Isn't an impact gun or a T-bar safer to use than a breaker bar so that equal force can be applied?
-
I've never tried taking an injector out with an impact gun but it might not hurt. The injector is really a precision part but is also pretty sturdy in my opinion. Let's see if anybody else ever did it. I definately wouldn't put one back in that way though. That would really lessen the chance of cracking the boss though.
-
There's really no need to take an injector out with and impact gun, if you need something that powerful to take the injector out than something is going to break.
Easiest way to do it is soak them down for a while with lubricant and use a breaker bar or what ever you like. If it starts to get hard to turn then retighten little by little and back them out little by little, just go easy, don't force it and use a lot of lubricant.
I just pulled my set, but I didn't have lubricant, went slowly and backed out and retightened often.
-
Injectors and front strut nuts... two things impact wrenches were made to loosen!
-
I've used an impact many times to take injectors out however I prefer the breaker bar. I find with the gun you are more likely to mangle the return barbs. Whatever tool you use, loosen, tighten rinse and repeat :) I loosen until I start to feel it binding up then I loosen it about 1/4 turn