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New ember new project

update

started on the engine this weekend, engine back from been soda blasted.
I have given it a good steam cleaning and de-greasing, base coat of vht cast aluminium to protect the alloy, proper paint when engine sorted.
started stripping the cylinder head, I will lap in the valves and replace stem oil seals.

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cheers
neil
 
Not had time to look at the springs closely, just had time to take photo and the heavens opened, back to normal English summer��
 
It’s the soda blast stuck to them, I am away working this week ,when I get home I will wash it off and post some photos ��
 
pic of valve springs, just soda blast, quick blast with wd40 wipe over good as new, no rust :thumbsup:

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That looks OK. Have you measured them up to check they are within spec for length? It might be that they have compressed from usage and are now too short and weakened. When I was in the trade we tested springs for how much they compressed for a given weight. Not sure what the spec is for that. Honda don't mention it. Given the cost of a set of new springs might be worth renewing them anyway.
 
update

started to work on cylinder head yesterday, cleaning and de-coking the valves, only found one issuse with an exhaust valve, see picture looks like i caught it just in time, as there is no damage to the valve seat in the head etc.

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Glad you caught that, and sure hope no damage from it. BTW, are you certain that you can lap 750 valves? On the GL1000, Honda cautions that the valves are stellite faced, and lapping will remove the thin coating. I had the seats ground on my GL1000 heads, and just installed new valves as they were fairly inexpensive @ ~$10 each for intakes and ~$15 each for exhausts. BTW, I just brought home a 1979 CB750F that I will be using for a rat rod project, not caring about appearance. Still, I'd rather try to clean up the baked-on mold and mildew on them than remove chrome. I have a set of GL1000 valve covers that had been chromed (poorly). I tried to remove the chrome but finally gave up and use them as temporaries when I remove the plain alloy covers for polishing.
 
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according to the Honda service Manuel you can lap in the valves no problem, it just says you cant grid them ??
there only a light lapping in anyway as the engine only done 28,000 miles, and they don't look to bad.

chrome on alloy ?? mine as you can see from the pic's, most of it has come off but I need to get the rest off.
I have spoken to a local chroming company and they say can remove the remaining chrome, and then they will just need polishing.
but that is a job for the winter.
 
AMC advised me against grinding the valves. He said, grind the seats and "lightly" lap the valves, only to "read' the valves seating pattern. The lightly lapped wear pattern should be concentric around the valve "face"? (the angled portion)
 
I agree. In the Navy, we would use Prussian Blue to check valve contact. I did that on my GL1000 heads after having seats ground ($10 and 10 minutes!) by a local automotive machinest and installing new valves. There is a very thin Stelite coating on the valves that you don't want to grind away.
 
update

Cylinder head now sorted :thumbsup:


Had a look at the petrol tank, lots of rust and crud inside, so i though i would give electrolysis ago,

washing soda (sodium carbonate) , car battery charger, steel anode (threaded bar) warm water :D.

read about it on a few forums and did some youtubing, this is what i came up with.
rust and crud in tank 37 years of it.
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anode and insulation
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anode fitted in tank, not touching the tank
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secured with battery charger attached
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result after 1 hour
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it will take sometime, i will leave it on over night and see what it looks like, I will post the results, I think it will take a few days to work properly.
 
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