Guinness
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| posted on 15/7/09 at 05:42 PM |
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Cylinder Head Refreshing?
Right, the cylinder head is off the mighty old Zed. Pretty sure it was HGF that was the problem.
The cylinder bores look ok, with no scoring or ridges. The tops of the pistons are manky and covered in black soot, as are the combustion chambers in
the head.
Exhaust valves are caked in black and the inlet ones are crusty white.
How do I go about the following? (If at all)
Cleaning the black crusty stuff out of the combustion chambers?
Cleaning the valves? (There is no money in the pot for new stainless ones!).
Re-seating the valves once I've cleaned them?
Then, has anyone in the North East got a valve spring compressor that will work on a bike head? Or any of the tools I'm going to need for the
above?
Cheers
Mike
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speedyxjs
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| posted on 15/7/09 at 05:51 PM |
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I used good old fashioned wet and dry 
How long can i resist the temptation to drop a V8 in?
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Benzine
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| posted on 15/7/09 at 07:00 PM |
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Get a machine shop to de-coke it? I have no idea how they do it but it's amazing. Locost: paraffin + toothbrush 
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MautoK
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| posted on 15/7/09 at 09:24 PM |
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quote:
Originally posted by Guinness
Exhaust valves are caked in black and the inlet ones are crusty white.
You sure?
I've always found it's the ex valves that get the crusty white deposit.
Carefully scrape off with a blade, taking due care of self and integrity of blade. (i.e. don't cut yourself and don't snap the blade)
John.
He's whittling on a piece of wood. I got a feeling that when he stops whittling, something's gonna happen. (OUATITW/Cheyenne)
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NS Dev
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| posted on 15/7/09 at 09:34 PM |
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valve cleaning is easiest if you can borrow a lathe for a bit, Hold them by the clean bit in the chuck and clean the rest with emery carefully. A
(cheap) drill in a vice works at a pinch.
The rest is just careful wire brush work, I usually use a brass one and paraffin.
Retro RWD is the way forward...........automotive fabrication, car restoration, sheetmetal work, engine conversion
retro car restoration and tuning
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Guinness
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| posted on 16/7/09 at 08:05 AM |
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quote:
Originally posted by MautoK
quote:
Originally posted by Guinness
Exhaust valves are caked in black and the inlet ones are crusty white.
You sure?
I've always found it's the ex valves that get the crusty white deposit.
Carefully scrape off with a blade, taking due care of self and integrity of blade. (i.e. don't cut yourself and don't snap the blade)
John.
You're right there. The head is now upside down on the workbench, so the position of the valves is reversed! Whoops.
This doesn't bode well for a rebuild does it!
I think I've found a valve spring compressor to borrow, so I'll have a go at removing the valves over the weekend. No access to a lathe,
so I'll be putting the valves in a drill. Any idea on the speed I should be using?
Cheers
Mike
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DarrenW
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| posted on 16/7/09 at 08:31 AM |
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I cleaned the pinto ones up using a cordless drill. Fastest speed, steady away with the emery. Spare battery on charge at all times. Ive got a cheapo
bench drill you can borrow. Steve coozer has a lathe and is closer to you.
I got my head skimmed and valve seats recut. Then lapped them in kind of by hand (got hold of valve stem in drill from behind the head and just kept
reversing the direction etc). I was happy once i had a uniform colour and width of lapped surface around valve and the seat. Easy enough to do but oh
so boring. Do you have 16 to do???
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Guinness
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| posted on 16/7/09 at 09:16 AM |
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quote:
Originally posted by DarrenW
I cleaned the pinto ones up using a cordless drill. Fastest speed, steady away with the emery. Spare battery on charge at all times. Ive got a cheapo
bench drill you can borrow. Steve coozer has a lathe and is closer to you.
I got my head skimmed and valve seats recut. Then lapped them in kind of by hand (got hold of valve stem in drill from behind the head and just kept
reversing the direction etc). I was happy once i had a uniform colour and width of lapped surface around valve and the seat. Easy enough to do but oh
so boring. Do you have 16 to do???
I'll ring Steve once I've got the valves out (all 16 of them!).
Where did you get your head done and roughly how much was it?
Mike
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DarrenW
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| posted on 16/7/09 at 10:14 AM |
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I got my head done at Paul Phillips engine services in Bishop Auckland. He skimmed 1mm off it (reluctantly but i took the risk), passed a tool through
the guides that reduces the diameter and recut the seats for about £80 cash 4 years ish ago. I ported the head myself. Probs loads of places closer to
you do similar work. Not sure if bike heads are different to work on. Is there anyone on Westgate road that do them or can recommend a local place?
While head is off it might be worth seeing if there are any well documented diy porting write ups for them. I followed des Hammills recommendations
for the pinto. Vizard also does similar good write ups (in his books). I would guess there are bike ones about too. I have a die grinder you can
borrow. The tools are available from Machine Mart (iirc). I used a little compressor, took a while waiting for compressor to catch up but not too bad
of a job. Mind you, the trick in reconning heads is knowing when to stop. I quick refresh maybe better.
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DarrenW
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| posted on 16/7/09 at 10:16 AM |
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Coozers lathe will probs make light work of cleaning the valves up. Using a lathe means you can be effective using a file to remove the thick crud and
then polish up with emery tape.
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DarrenW
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| posted on 16/7/09 at 10:27 AM |
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Ive heard good reports from this place before, just outside Durham;
http://www.cleasbypes.co.uk/
Couple of others here (never heard of them);
http://www.yell.com/ucs/UcsSearchAction.do?keywords=Engine+Reconditioning&companyName=&location=Newcastle&scrambleSeed=25279515&search
Type=advance&M=&lastKeyword=Engine+Reconditioning&lastClarifyIndex=&lastClarifyOptions=&lastSearchall=&lastSearchallTax=&l
astbandedclarifyResults=&bandedclarifyResults=&ssm=0&x=0&y=0
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