htr

Well-Known Member
Getting on to projects that have been sitting on the 'shelf' for ages. I've a K series cylinder head I'm reconditioning. It's a good one and it's been plained in prep' to refitting. I've also used my Dremel to open up the coolant apertures a bit.

Question: The valve guides are worn. I've a replacement set here, are these something I could fit myself. I could make up some sort of drift using an old valve to get them out...

Advice, or cautions, please.
 
It's unusual for valve guides to wear in the K series engine. In the days of offset rockers, then yes the side loads on the valve caused guide wear. With the overhead bucket follower like the K (and most other OHC engines), the valves don't get side loads, so wear isn't common.

Don't confuse guide running clearance for guide wear. There will be a small amount of slack in the guide, as the valves heat up, this clearance will close. Also a clean oil free valve stem will feel loose in a dry guide. There has to be some space for the oil, or the valve will stick.

So before contemplating removing the guides, compare the slack a new valves in new guides. Then decide if you want to go through all the work needed to change what's in there.

I've a replacement set here, are these something I could fit myself. I could make up some sort of drift using an old valve to get them out.

It is possible to make up a drift to fit the guides. However it's normal practice to reem the guides to final size, once they're in the head. This is to ensure the running clearance is set at the minimum, should the guide close when it's pressed in. Once the guides have been reemed to size, the valve seat will then need cutting to match the position of the new guide.

Like I said, if the guide clearance is within spec, then leave well alone. ;)
 
Thanks Nodge, I've been looking on-line at a w/shop manual and decided it wasn't a job for me.

However, I have a K-series motor on a stand that needs a cylinder liner resealed in So I'll have a go at that. I plan to leave the piston in the sleeve and just remove the big-end cap then push the whole lot up. Clean up the key areas and then slide it back in and clamp it down again. I'm using Hylomar Blue as the sealant. That plan should work - shouldn't it?
 
However, I have a K-series motor on a stand that needs a cylinder liner resealed in So I'll have a go at that.
That's an easy DIY job .;)
I plan to leave the piston in the sleeve and just remove the big-end cap then push the whole lot up
That's the way they're fitted at the factory, so it's perfectly acceptable, and the way I do it.
Clean up the key areas and then slide it back in and clamp it down again.
That's the key to doing the job correctly. Use brake n clutch cleaner for cleaning the surfaces.
I'm using Hylomar Blue as the sealant. That plan should work - shouldn't it?
Hylomar Blue is the only sealer that's recommended, and was the factory sealer used. ;)

I've got some pictures of one I did somewhere. I'll dig them out and post them. ;)
 
Thank you Nodge.
I found this on the The Rover 75 MGZT owner club site. I've always found this an interesting and encouraging read as wall as the K-engine pages. I'm intrigued to consider fitting the VVC exhaust valves to a st'd K-series head.
 
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