PJF

Hi, ive got a 97 impreza turbo with an exhaust valve stuck open, ive taken the head off but am unsure of how to free it. Is it a case of soaking it with lubricant/brake cleaner etc and giving it little taps or is there a better/easier way of freeing it off.
Any help would be great thanks.

Turbotits

iTrader: (2)

I would suggest removing the valve and replacing it. Obviosly means lapping the new valve in etc. While you have heads off do the lot with new seals etc.

The valve is possibly bent

merlin24

iTrader: (1)

As above, possibly a bent valve if its stuck open ( should be a witness mark on the piston crown from the valve contact if it is a bent valve ) - once out, check the valve guide for any damage.

Mick

PJF

Thanks for the advice, i didnt really think about the valve being bent as it does'nt look bent but it makes sense to replace it just in case.
Thanks for the quick reply.

Fudgey

iTrader: (1)

Will need a new valve and guide. Will probably have to get the guide inserted at an engine specialists.

PJF

I would ideally like to do it myself, is it possible or would it have to be a machinist job? Id really like to keep costs down which is why im doing it myself, so back to my first question, is it possible to free a stuck valve? Im assuming if i can free it i will then be able to tell if its bent, if it isnt happy days, if it is then replace.

PJF

I meant engine specialist not machinist, was half asleep when i wrote the last post.

Fudgey

iTrader: (1)

Well if a valve is stuck there will be 2 reasons why.
1. the valve is ****ed
2. the guide is ****ed
so as a rule of thumb, you would replace both.

i cant see it costing a huge amount to have a singe guide fitted. taking into consideration you needing to buy a valve spring compressor and stuff to lap valves it etc

as for how to free it, i am sure a hammer will move it....

EDIT:
I am also assuming that you have removed the cams and lifters, and the valve is still stuck?

PJF

A hammer lol, it crossed my mind for a moment but i managed to stop myself. Yep the cams are off (couldnt get to the head bolts otherwise) and its still stuck open. The valve is coroded in, i had the inlet manifold off and a load of rain water went through the scoop and into the cylinder. I got it out and turned the engine by hand every week to keep it all moving/free but then gave up and now its stuck. I shall get acouple of prices for a garage to do it and maybe see what people on youtube use to compress springs maybe some methods are ok, (probably not though) but i shall see if i can find some anyway lol. Thanks for the input everyone.

Fudgey

iTrader: (1)

How far is open? fully? its probably not bent then if you said it is corroded, and may clean up if you can get it out.

but the guides are bronze and quite soft metal, so trying to clean that may damage it.

you might be able to make something up the screws to the head, then as you tighten it, it pushes the spring down.

where abouts are you?

PJF

Im not sure if its fully open but if it isnt its not far off. Ive spoke to a mate whos gonna bring his valve compressor down at the weekend, fingers crossed its suitable. Im in Bristol mate.

Fudgey

iTrader: (1)

no too far away then, if you get stuck let me know as i have a spring compressor too. im near swindon.

PJF

Thanks for the offer its very much appreciated. I will see how it goes on the weekend, if i cant sort it i shall prob pop into the local impreza engine specialist and see if i can get them to fit a new valve.

PJF

Well, after soaking the valve in wd40 for 2 weeks with no valve spring attached and no movement i came to the conclusion violence was the only course of action. Malgrips are more effective than wd40 lol. Im assuming its a tiny bit bent although it looks fine. When i fit a new valve is it just a case of reseating it or does it need to be cut to shape and reseated?

merlin24

iTrader: (1)

The new valve will come with the correct angle cut on the face, so provided the valve seat isnt pitted or damaged then a quick lap in with a dab of fine grinding paste and good to go.

Mick