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  #81 (permalink)  
Old 09-27-2021, 11:05 AM
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Reports of valves fish scaling have been on the FE and Mustang forums
Get a child’s science kit microscope an look at your valve stems
I just used one to check the rings on this 390, they look beautiful reusing them
It’s a handy tool to have

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  #82 (permalink)  
Old 09-27-2021, 03:44 PM
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Quote:
Originally Posted by Jerry Clayton View Post
what caused those marks on the valve stem just below the keeper lock grove??
That is a very good point, what are those marks?

And how much valve lift do you have?

Please post your camshaft specs.
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  #83 (permalink)  
Old 09-27-2021, 05:28 PM
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The valve is off center because of the worn guide. Those marks look like where the plating or the case hardening has been worn off by the keepers. That should not happen. Counterfeit part? Hardening or plating prob?

A spring removal and valve inspection at 500, 1500, 3000, 5000 miles would be a good idea on the fresh motor. Pack nylon rope into TDC cylinder, couple hours

These motors were engineered with the valves lubed by lead in the fuel. USA fuel has friction modifiers in it to replace the lead somewhat, probably not allowed in EU fuel. Add Hapco lead substitute, a $50 gallon treats 200 gal gas

A Howard Cams 93360 11/32- .530 type seal with a band instead of spring would form a hydrodynamic seal allowing oiling where a spring seal will wipe off oil and stop oiling
I’m using the no band 3/8” - .530” 93320 Howard Ultimate seal, the 11/32” 93311 has .500 guide, these seals oil the valves too.
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Last edited by sunman; 09-28-2021 at 03:32 PM..
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  #84 (permalink)  
Old 09-28-2021, 07:10 AM
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This didn't all happen just over night----It was maybe lack of compatible lubricants/fuel issues?????? To be so bad pretty much on all cylinders---wrong choice of oil to go with fuels from that area???????excellant choice of seals restricted amount of lube to valve guides which then wore enough to kill the seals which then let in huge amounts of oil sucked thru the intake guides???????
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  #85 (permalink)  
Old 10-12-2021, 04:21 AM
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Hi guys and sorry for my late reply.

Here is a video of the valve/rocker movement. All are the same of course.

For BRENT here is too a picture of the reference seen on the camshaft.

I think there's not doubt now I have a problem with the pivot/rockers on the valves.

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  #86 (permalink)  
Old 10-12-2021, 04:23 AM
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  #87 (permalink)  
Old 10-12-2021, 04:39 AM
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That cam is 248/248 @ .050", with a .638" gross valve lift. You will lose .015-.020" lift to valvetrain deflection, so at 100% optimal, you're at .638" lift. In actuality, you were probably getting about .615" lift at the valve.

Hard to tell anything from a side video, but it looks like the rocker starts on the intake side of the valve stem and rolls through. If you're opening the valve more than .600-.650", then you're going to get an exaggerated view.

I don't know what you'll see now as far as geometry with a valve/valve guide worn that bad, but the T&D rockers notoriously set up perfectly on an Edelbrock head with a standard length FE valve. In your video, I can see the valve moving back and forth in the guide. That will skew the results of a geometry check. If you have .030-.040" of wear, that would mean that the valve can move side to side in the guide by at least .015", which can affect the geometry quite a bit.

I would be looking at the amount of wear that you see on the stem. If there's more wear there than .600" lift worth, then that narrows the issue down to a surface finish/plating issue.
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Last edited by blykins; 10-12-2021 at 05:36 AM..
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  #88 (permalink)  
Old 10-12-2021, 12:08 PM
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If it is a rocker thrusting issue the guide wear will be much more at the top of the guide and much less at the bottom.
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  #89 (permalink)  
Old 10-12-2021, 03:57 PM
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A bit hard to tell until you get the valve guides replaced, and the valves reseated.

The roller should start on the side CLOSEST to the rocker shaft, sweep over centre, then be on the side OPPOSITE of the rocker shaft AT HALF VALVE LIFT, then sweep over centre near full lift. The pattern should be near centred over the valve stem, the narrower the better.

Your rocker does not have that pattern at all.

Put some engineers blue on the valve stem and watch the pattern the roller leaves.
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  #90 (permalink)  
Old 10-12-2021, 05:12 PM
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Could it be possible the engine in question was running extremely rich for its entire life and that's what caused the accelerated wear? This is more of a question than a conclusion, although I think it's possible.
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  #91 (permalink)  
Old 10-12-2021, 05:21 PM
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Quote:
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Could it be possible the engine in question was running extremely rich for its entire life and that's what caused the accelerated wear? This is more of a question than a conclusion, although I think it's possible.
Guide wear like the owner has, is not caused by excessively rich A/F ratio.

Even it somehow ran continuously at 6:1 (typical cold cranking fuel requirements).
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  #92 (permalink)  
Old 10-14-2021, 03:19 AM
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Quote:
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That cam is 248/248 @ .050", with a .638" gross valve lift. You will lose .015-.020" lift to valvetrain deflection, so at 100% optimal, you're at .638" lift. In actuality, you were probably getting about .615" lift at the valve.

Hard to tell anything from a side video, but it looks like the rocker starts on the intake side of the valve stem and rolls through. If you're opening the valve more than .600-.650", then you're going to get an exaggerated view.

I don't know what you'll see now as far as geometry with a valve/valve guide worn that bad, but the T&D rockers notoriously set up perfectly on an Edelbrock head with a standard length FE valve. In your video, I can see the valve moving back and forth in the guide. That will skew the results of a geometry check. If you have .030-.040" of wear, that would mean that the valve can move side to side in the guide by at least .015", which can affect the geometry quite a bit.

I would be looking at the amount of wear that you see on the stem. If there's more wear there than .600" lift worth, then that narrows the issue down to a surface finish/plating issue.
OK Brent so first of all I'm going to replace the guides and once done check the rockers/pivots.

Problem: Craftperformanceengines doesn't reply to my emails !!!! How can I order the new guides ???

Thanks.
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  #93 (permalink)  
Old 10-14-2021, 03:20 AM
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Quote:
Originally Posted by Gaz64 View Post
A bit hard to tell until you get the valve guides replaced, and the valves reseated.

The roller should start on the side CLOSEST to the rocker shaft, sweep over centre, then be on the side OPPOSITE of the rocker shaft AT HALF VALVE LIFT, then sweep over centre near full lift. The pattern should be near centred over the valve stem, the narrower the better.

Your rocker does not have that pattern at all.

Put some engineers blue on the valve stem and watch the pattern the roller leaves.
Gary, as Brent said my guides are too worn to check rockers travel/pivot so I'm going to replace guides and check once done.

Thanks, OliveR
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  #94 (permalink)  
Old 10-14-2021, 03:56 AM
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Quote:
Originally Posted by CLV8 View Post
OK Brent so first of all I'm going to replace the guides and once done check the rockers/pivots.

Problem: Craftperformanceengines doesn't reply to my emails !!!! How can I order the new guides ???

Thanks.
You will need to replace the guides, valves, and then do a valve job before you check geometry.

Send me an email. I know I can get the valves, let me see if I can get you the guides as well. I'll sell to you at my cost plus the shipping.
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Old 10-14-2021, 07:05 AM
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That is service after the sale.

John
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