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Author Topic: Cylinderhead question(updated pictures)  (Read 2166 times)

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Offline KirkBurner

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Cylinderhead question(updated pictures)
« on: February 11, 2014, 02:17:31 PM »
Updated with the last picture

Is this cylinderhead already milled as much as it can be milled?
Is it milled more on one side then the other due to the darker markings?



The damage in the picture below will this disapear with simple milling of the head?


« Last Edit: February 12, 2014, 10:59:38 AM by KirkBurner »
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Offline Old Scrambler

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Re: Cylinderhead question
« Reply #1 on: February 11, 2014, 02:27:01 PM »
The stains are from the head gasket and may indicate minimal metal has been removed. Glass it or plane it to measure any irregular surfaces.  Is that a scratch or a crack-line leading from the chamber to a stud-hole?  Clean it or blast it before further work is commenced. If that scratch is deep.............its land-fill.
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Offline KirkBurner

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Re: Cylinderhead question
« Reply #2 on: February 11, 2014, 02:39:26 PM »
Forgot to say.. it has/had a copper gasket...

its a "scratch" try to use the Micrometer to measure it tomorrow ... and I will talk to the machineshop about the depth of the scratch
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Offline KirkBurner

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Re: Cylinderhead question(updated pictures)
« Reply #3 on: February 12, 2014, 11:02:12 AM »
TTT
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Offline LesterPiglet

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Re: Cylinderhead question(updated pictures)
« Reply #4 on: February 12, 2014, 11:08:16 AM »
Why not run a weld over the scratch before milling?
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Offline MRieck

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Re: Cylinderhead question(updated pictures)
« Reply #5 on: February 13, 2014, 03:23:00 PM »
That line looks like more of a dent and it goes across the stud hole. Interesting.
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Offline LesterPiglet

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Re: Cylinderhead question(updated pictures)
« Reply #6 on: February 13, 2014, 03:45:56 PM »
Is there a matching mark on the cylinder side?
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'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Draw and drawer. Could care less/couldn't care less. Bought/brought FFS.


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Offline bjbuchanan

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Re: Cylinderhead question(updated pictures)
« Reply #7 on: February 13, 2014, 09:49:04 PM »
Quote from: MRieck on February 13, 2014, 03:23:00 PM
That line looks like more of a dent and it goes across the stud hole. Interesting.

I agree with MRieck, that looks like a dent. Installation or removal, could be from putting it down on a workbench. Surprisingly easy to damage the aluminum, especially with the weight of the head helping downward

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Offline KirkBurner

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Re: Cylinderhead question(updated pictures)
« Reply #8 on: February 14, 2014, 01:06:23 PM »
No markings on hte cylinder side of the fit.

But, will this likely cause a leak if untreated?

Im gonna have the head sent over to the machine shop, for valve seat cutting aswell as milling.

should this be enough to clean up the damage?
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Offline LesterPiglet

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Re: Cylinderhead question(updated pictures)
« Reply #9 on: February 14, 2014, 01:29:30 PM »
If it's too deep to mill out it's ideal for early gasket failure.
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'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Draw and drawer. Could care less/couldn't care less. Bought/brought FFS.


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Offline lucky

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Re: Cylinderhead question(updated pictures)
« Reply #10 on: February 14, 2014, 01:48:49 PM »
You should NOT be milling a motorcycle cylinder head unless you really have to.

IT IS NOT A CAR ENGINE!

A clean up cut to the absolute minimum and then you will have to check piston clearance with the valves etc.,.

Just do not do it.
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Offline alacrity

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Re: Cylinderhead question(updated pictures)
« Reply #11 on: February 14, 2014, 02:27:51 PM »
Yeah this looks like something hard and heavy and sharpedged got dropped on it or vice versa.
I'm with the person who said see about having it filled with weld, then have the head face surfaced to be perfectly flat removing the absolute minimum of material possible to achieve that.

i did one of these engines and didn't have it surfaced - the available head gasket and how that interfaces with the relatively low torque settings for the head nuts meant  - you guessed it - the #$%* leaked.

After that, I have had a great local machinist measure and inspect all the mating surfaces for flatness.  No more problemos.
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Offline KirkBurner

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Re: Cylinderhead question(updated pictures)
« Reply #12 on: February 15, 2014, 01:10:28 AM »
In regards to piston clearance for the valves,

I have Yoshi´s 812 with indents for the valves in them, I have no idea of how much this will give me of extra clearance.

And using a copper gasket, I understand it will to some degree leak no mater what?
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Offline KirkBurner

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Re: Cylinderhead question(updated pictures)
« Reply #13 on: February 15, 2014, 03:33:18 AM »
When doing some research on the interwebs I came across http://www.aluminumrepair.com

HTS-2000

is worth trying or should I stay away from it ?
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Offline calj737

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Re: Cylinderhead question(updated pictures)
« Reply #14 on: February 15, 2014, 04:56:12 AM »
What you "should" do is take the head to a qualified machine shop and have them make a determination with mechanical measuring tools and applying experience. Speculation and trial-and-error of internet-based remedies for unknown maladies is a sure fire way to trouble.

But it's your bike, and it's your butt in the seat.
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Offline KirkBurner

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Re: Cylinderhead question(updated pictures)
« Reply #15 on: February 15, 2014, 06:39:52 AM »
I am in touch with a shop... Today my stuff fom cyclex arrived so now i just hva to head up to the shop
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Offline bwaller

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Re: Cylinderhead question(updated pictures)
« Reply #16 on: February 15, 2014, 08:08:44 AM »
If you can repair that dent and clean up the face, consider an MLS head gasket instead of copper. Copper will always weep some but if you have good straight surfaces the MLS should seal better.
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