Valve Guide Removal Tool

[JonnyAlpha]

Hi,

I need to make a Valve Guide Removal Tool and need some advice, having never machined anything before.
We have a Warco Hobby Lathe to machine it on but wondered what material would be suitable?
I have an old Classic Mini Top Arm Suspension Spindle and though about modifying that but it may be hardened steel and wasn't sure about machining it?

Thanks for any advice

 

[RonA]

The ones Ive seen have been made of brass or bronze to avoid damaging the guide
RonA

 

[Popcorn]

Just use a normal punch that's smaller in diameter than the valve guide but bigger than the hole in the guide.
It's not like your going to be refitting them.

 

[JonnyAlpha]

Just use a normal punch that's smaller in diameter than the valve guide but bigger than the hole in the guide.
It's not like your going to be refitting them.

But I need something that fits in the guides and a shoulder that sits on the guide but smaller than the hole that the guide sits in.

 

[Popcorn]

You don't need a special tool to remove them, I've always used a straight punch for removing the guides.
What your talking about is a steeped punch, but it's easy enough with a normal straight punch.

 

[mr haynes]

I've used an old valve with a sleeve welded to it to give flat face.
I normally pressed guides in and out
Think the sleeve i used for the mini was the engine steady one

 

[Melvyn Best]

I have changed dozens of A series valve guides using a decent drift of the correct diameter with a section turned down to the valve stem diameter. For fitting I use a brass drift with a valve stem dia section but larger dia body than the guide ,and a spacer that limits how far the guide goes into the head. For cutting the seats I use a hand operated cutter even with hardened seats , obviously if your head doesn’t have unleaded seats it’s probably worth getting a machine shop to fit them and the guides at the same time
Make sure the valve guide is a tight fit in the head, I spent a couple of weeks trying to diagnose an intermittent misfire on a Metro once that always behaved when I was testing that I eventually traced to a “floating” valve guide

 

[stormin]

I used a small cap head screw that was slightly smaller than valve stem diameter and simply used a punch in the end of that to remove and install land rover valve guides.

 

[8ob]

You can sleeve a worn guide in situ, an eight valve head would take about an hour and there is no need to recut the seats, a simple grind/lap will do the job. The reamer centres on whole length of the existing guide, install the new sleeve with air rattle gun and press through a valve sized ball which stretches the guide into its new bore. Simple task, I have used these for years and not seen a failure.

Bob

 

[Gwil]

Really don't like to drift guides out on motorcycle heads, some castings are pretty thin. I'd make up a simple puller, mild steel is perfectly adequate, and (gently) heat the head beforehand.

 

[JonnyAlpha]

Sorry, I missed many of these replies, with some great info.
Anyway, I made a tool yesterday :-)

It is made with a piece of scrap bar I had lying around (poss just mild steel), what would be the best way to harden it to avoid damaging it when hammering the guides out?
IIRC when at school we used to heat up the piece with a gas torch and then dip it in a can of oil?

 

[Gareth_16V]

Nice work on the tool. I made a similar one to do the valve guides on a motorcycle head - same number of valves you have there. I didn't harden it at all, and other than some "mushrooming" of the end that gets hit with a hammer, I didn't see any other problems.
I think the commercially available ones use a slight undercut where they meet the valve guide so that they don't deform the guide on the way in. But seeing as all valve guides need reaming after fitting anyway (and the valve seats recut) this shouldn't be a problem - any burrs from driving them in would be dressed/removed when the guides are sized.

 

[JonnyAlpha]

Nice work on the tool. I made a similar one to do the valve guides on a motorcycle head - same number of valves you have there. I didn't harden it at all, and other than some "mushrooming" of the end that gets hit with a hammer, I didn't see any other problems.
I think the commercially available ones use a slight undercut where they meet the valve guide so that they don't deform the guide on the way in. But seeing as all valve guides need reaming after fitting anyway (and the valve seats recut) this shouldn't be a problem - any burrs from driving them in would be dressed/removed when the guides are sized.

Thanks Gareth,
Wasn't going to hammer in the new guides, I'd rather press them in. Missed out on an Arbour press for £25 the other day so may look at making one like this one, although it seems a bit over engineered, maybe something simpler, just not sure how much pressure you'd need to press in the new guides?

 

[Gwil]

Thanks Gareth,
Wasn't going to hammer in the new guides, I'd rather press them in. Missed out on an Arbour press for £25 the other day so may look at making one like this one, although it seems a bit over engineered, maybe something simpler, just not sure how much pressure you'd need to press in the new guides?

I think the answer may be not as much pressure as you think! I used to put in motorcycle guides (bronze) with the combination of temperature differential and a humungous vice.

A press would certainly be easier though, just from the point of view of holding the head. I suspect a 10 ton would do it.