Need to replace injector seals on 1.8 valver! But How

[joby 0]

In the process of a 9a conversion and decided to strip the inlet manifold down for spraying 2 injectors popped out nicely, but the other 2 took me at least an hour to get out :shrug: eventually when they popped out the top hats came off and stayed in the injector insert! I have ordered some new seals but the top hats didnt seem to want to go back on "very tight fit" But you must have to remove the top hats to get the seal on :? Any ideas please!!

[mattnorgrove 0]

Had this happen to me on my old KR. I used a suitable self tapping screw, quite a short one, securely taped to the end of a long bladed Phillips screwy. Then pulled the screw/injector cap out with long nosed pliers. Took minutes to do, and breathed a heavy sigh of relief afterwards. I used replacement injectors from eBay from a Merc, without the end caps afterward. Ran beautifully.

 

HTH

[davidwort 0]

top hats shouldn't need to come off to get new main seals on, injectors always come out of the manifold better when the engine is warm as the old main seals get quite hard with age.

putting new main seals on can be a bit of a struggle but shouldn't be too bad, new ones should be much more pliable.

I've heard people fitting top hats back on with a bit of loctite, I'd rather have them on there as they are actually heat shields for the end of the injector.

[joby 0]

Thanks for the advice chaps! Was thinking about taking the top hats of altogether but after reading a post on club gti forum somebodys car ran badly without them :shrug: I suppose they are on there for a reason, Something to do with the spray pattern maybe

[davidwort 0]

only reason I can see there being problems without them is if the hot running 16v head affects the end of the injector without them in place,

or

if the main seal if knackered, then the top hat seal my help prevent air leaking in.

[joby 0]

There was A big discussion on club gti about it and the guy bought merc injectors and put them in without the hats and he ran it for a while but it ran rough so he replaced them with the old ones and it ran better, He was convinced the problem was lack of hats :shrug:

[davidwort 0]

yeah, I remember that, but so many people have tried the basic k-jet injectors (like the 8v GTI ones without the hats) and they've worked Ok, that I'm sure that was down to air leaks from poorly mounted fuel lines and dodgy main seals rather than anything to do with spray pattern. K-jet injectors can have pretty crap spray patterns and cars will run OK, it's possible one or more were really badly faulty from new but it seems unlikely.

Those hats are actually described by VW as heat shields and it makes sense on a 16v.