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Hi All,

Has anyone sucessfully removed and refitted valvesprings without taking the head off?

I fear a big job coming on to fit my new springs

Yep, just make sure you have plenty of compressed air (volume AND pressure) and a good pair of earplugs.

IMHO don't even contemplate it without at least 5 CFM @ 90psi

Cranking the pot to TDC just incase you drop the valve is also a good idea.

Of course you'll need a tounge spring clamp, but I suppose a large ringy would suffice.

Woo wrote:Yep, just make sure you have plenty of compressed air (volume AND pressure) and a good pair of earplugs.

IMHO don't even contemplate it without at least 5 CFM @ 90psi

Cranking the pot to TDC just incase you drop the valve is also a good idea.

Of course you'll need a tounge spring clamp, but I suppose a large ringy would suffice.

We have a HUGE compressor capable of supplying plenty or air (the thing is nearly as big as the car!)

My concern is getting the spring compressors onto something to compress the spirngs. On the last head I did it with head removed and just tightened the compressor onto the combustion chamber side - if you get what i mean?

They did this on Tricked Out the other day on Foxtel
http://www.diynetwork.com/diy/ab_engine ... 02,00.html

It seems you'd need a special valve spring compressor that just works from the cam-side of the head.


Didn't look too fiddly when he did it:

WOW!

I'd be busy making that tool, but I cant see the need to do this job over and over, it's rare to change springs, let alone wanting to change them on the car...

Will rip it apart tonight

Sean wrote:We have a HUGE compressor capable of supplying plenty or air (the thing is nearly as big as the car!)

My concern is getting the spring compressors onto something to compress the spirngs. On the last head I did it with head removed and just tightened the compressor onto the combustion chamber side - if you get what i mean?

Yep, gotcha, thats a G-clamp valve spring compressor, really all thats needed when the heads on the bench.

Here is a basic run down of how-to
Put your ear plugs in.
Connect the air in the spark plug hole and then turn it on.
Use a tube socket or piece of solid tube to compress the springs, it's not going to be easy and it will probably pay you to give the tube a decent crack with a hammer to release the collets.
I like Babalouies valve spring press, very nice piece of kit
As your compressing the springs the valve is being held in place by the compressed air (hence volume and pressure).
When you have the spring compressed just slide a large open ended spanner or "modified" screwdriver under the follower cap (tappet) guide and trap the compressed spring.
Remove the tube and the collets.
Cover with a large rag and release the springs. They go-off with a bang so be careful.

Replacing the springs is the reverse of removal, noting that the new springs will be MUCH harder to compress than the stockies.

Oh and yeah, you have to do that for all 16 valves

Good Luck

Your removal method is so much more technical then mine...

I end up taking teh head off again.

Basically get a big deep socket (like used formage wheels) and place it on teh retainer with the head on the bench with a couple of rubber mats below it.

Than WHACK it hard with a big hammer, the sping compresses and as long as you have cleaned all of teh gunk off, the retainers pop out as do the clips and shebang one valve done. I've got plenty of spares so don't need to worry about bending a valve if I hit it worng...

That said, haven't lost one yet

Oh yes, call me dodgy.

Sean wrote:Basically get a big deep socket (like used formage wheels) and place it on teh retainer with the head on the bench with a couple of rubber mats below it.

Than WHACK it hard with a big hammer

That method seemed to work quite nicely when Geoff did his head stuff, although installation was an absolute pain! I know I'd be buying the tool Babs posted if I had to do it more than once.

Would one of these work ??

Brett_MX5 wrote:Would one of these work ??

Not sure if there is the room to use one of those on an MX5 head...would work on a Honda head since they have a rocker arm you can remove but on our heads there is a lifter boss in the way....

Babalouie wrote:Not sure if there is the room to use one of those on an MX5 head...would work on a Honda head since they have a rocker arm you can remove but on our heads there is a lifter boss in the way....

Yeah I was thinking the same thing - I didn't have a good look at the valvetrain when I had the rocker cover off so I wasn't sure if there was enough room

you might be able to get that tool around the boss and still get the spring...

Cost is about probably $24 (most expensive part being the cheapo ratchet socket set) and $2 for the clamp itself.

Worked absolutely beautifully.