heard a rumour, compressed air to remove valve springs

troystanton78 · 22-01-2010, 06:19 PM

got the official diagnosis on the xr8, valve spring it is, going to attempt this myself with a few mates over the next couple of weekends, i heard a rumour that if i make a fitting for my compressor that fits into spark plug socket, that the pressure should be enough to hold the valve up enough to remove and replace the springs, has anyone heard of this working or any other ideas/tricks to not have to remove heads
cheers

ronwest · 22-01-2010, 06:38 PM

Yes, compressed air works.

Another way is to feed a length of cord down the plug hole, enough to cover the top of the piston when piston is btdc by an inch or so, then rotating piston to as close to tdc as possible. Cord sits up against valves preventing them from dropping.

I've used both ways successfully.

edit: obviously you'd leave the end of the cord hanging out of the plug hole so you can remove it when finished ;)

**Whoosha** · 22-01-2010, 06:39 PM

Thats how I did mine, we used the screw in adapter from a compression tester to fill with air .

troystanton78 · 22-01-2010, 07:04 PM

excellent, might even start tonight, where can i get my hands on one of these compression tester parts, bloke at work was going to modify an old spark plug, but he's on holidays for another 2 weeks

lofty · 22-01-2010, 08:55 PM

Have you ever tried to bash the guts out of a spark plug? Difficult & dangerous in my experience.

Kryton · 22-01-2010, 09:24 PM

Quote:

Originally Posted by lofty

Have you ever tried to bash the guts out of a spark plug? Difficult & dangerous in my experience.

Wouldnt you just use a pedestal drill and drill it?

**GasoLane** · 22-01-2010, 09:30 PM

I used the compressed air method on an old V12 Jag a long time ago, borrowed the air/sparkplug fitting from a mate in a workshop, so someone must make them.

Try asking your local Repco? NOT StuporCheap!

mik · 22-01-2010, 09:32 PM

so you want one of these,
http://www.matcotools.com/Catalog/to...&page=3&#31105 the third pick down, sorry i don`t know where to get one locally.

**GasoLane** · 22-01-2010, 09:53 PM

How about.....

http://www.autotools.com.au/catalogu....php/10/46/416

jeffb · 23-01-2010, 10:03 AM

I used compressed air to do mine; I just used an Enzed fitting with a bit of hose on it. Make sure the piston is at TDC so if you lose air for some reason there is 1/2 a chance of salvaging it if the valve falls. but in doing so you have to make sure the motor will not spin, if its manual leave it in gear at TDC if its auto I usually use a socket and bar on the crank to hold it, if it even tries to move at all. Also make sure you change the valve stem seals while you are there.

lotus · 23-01-2010, 01:22 PM

Quote:

Originally Posted by jeffb

I used compressed air to do mine; I just used an Enzed fitting with a bit of hose on it. Make sure the piston is at TDC so if you lose air for some reason there is 1/2 a chance of salvaging it if the valve falls. but in doing so you have to make sure the motor will not spin, if its manual leave it in gear at TDC if its auto I usually use a socket and bar on the crank to hold it, if it even tries to move at all. Also make sure you change the valve stem seals while you are there.

Only problem with doing this way is if the bar slips off you lose pressure and the valve will drop. How we used to do it when I worked at Ford (many yrs ago) was take all spark plugs out and fill the cyl you are doing with compressed air,give the spring a light hit with a hammer(to break seal around colletts) keep the air supply up to it,do both valves and seals,then remove air supply.
Do this for every cyl. never had one drop.
If you do it this way, make sure if manual, put in netural and auto in park.

troystanton78 · 23-01-2010, 03:07 PM

good info lads, i was going to start this morning but it quickly got into the 40's out here, so i've postponed the start, and, i didn't realise i would have to remove so much to just get to the rocker covers, a few trips to the shop for tools maybe required through out this exercise

mik · 25-01-2010, 11:32 PM

i reckon one of these would be handy too , i always had one of those big ugly arkward buggers or made something up in the shed, http://buy1.snapon.com/catalog/item....re&dir=catalog

xr8ute · 26-01-2010, 05:47 PM

Quote:

Originally Posted by mik

i reckon one of these would be handy too , i always had one of those big ugly arkward buggers or made something up in the shed, http://buy1.snapon.com/catalog/item....re&dir=catalog

I used one of those last time I changed valve springs without removing the heads. Wasn't a Snapon model though, just a $20 cheapie from Autopro. Did the job.

naughts · 26-01-2010, 06:30 PM

HINT:
Put a socket on the retainer and give it a whack first. It loosens the collets.

troystanton78 · 30-01-2010, 07:05 PM

lookin like i just don't have the time to do this myself, any guesstimates on a cost from the local mechanic, the cars done 200 *** + k's so should i probably change them all or just the busted one (s)

troystanton78 · 04-02-2010, 09:36 AM

so she went in this morning, waiting for the damage call, hoping its not to excessive

troystanton78 · 04-02-2010, 07:15 PM

official verdict is in, no. 2 cyl inlet valve spring done and dusted, everything else looks mickey mouse still, 3 to 4 hours labour beats tryin to do it myself, could just imagine all the swearing and kickin stuff around if it didn't go as i planned, good thing is i should have around 400 left to play with, any suggestions on what i could do with this coin