Author Topic: I've been inside an engine before, I assume this is bad...  (Read 1492 times)

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Offline ncstatecamp

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I've been inside an engine before, I assume this is bad...
« on: December 02, 2013, 10:00:40 pm »


Not sure how to read valves... Are these shot? I was planning on trying to reuse these. No idea the mileage here....

AJK

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Re: I've been inside an engine before, I assume this is bad...
« Reply #1 on: December 02, 2013, 10:49:43 pm »
Not sure why you call this bad? You would be surprised how nice things will look after a good cleanup. Everything looks ok to me & typical of what you would see on a normal running motor. It looks a tad oily, but moreso like it was running a bit rich.
  There is no evidence of chamber damage & the exhaust valves have normal crust with a normalish colour.

Clean everything up, then you can move onto the next step of checking for worn valve guides which would be a better indicator.

Perhaps others could chime in.

Offline martin99

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Re: I've been inside an engine before, I assume this is bad...
« Reply #2 on: December 02, 2013, 11:12:32 pm »
Not sure why you call this bad? You would be surprised how nice things will look after a good cleanup. Everything looks ok to me & typical of what you would see on a normal running motor. It looks a tad oily, but moreso like it was running a bit rich.
  There is no evidence of chamber damage & the exhaust valves have normal crust with a normalish colour.

Clean everything up, then you can move onto the next step of checking for worn valve guides which would be a better indicator.

+1. Carry on sir!
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Offline kammery

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Re: I've been inside an engine before, I assume this is bad...
« Reply #3 on: December 03, 2013, 04:14:49 am »
 Put the spark plugs back into there holes . Fill the combustion chamber with water . Shoot compressed air into each port . If the valves are leaking you will see air bubbles . Exhaust valves will run a little hotter than intakes .

Offline reddyvv

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Re: I've been inside an engine before, I assume this is bad...
« Reply #4 on: December 03, 2013, 08:06:24 am »
Looks perfectly fine to me. Give 'em a good lapping job, new seals and go on your way.

Offline Bankerdanny

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Re: I've been inside an engine before, I assume this is bad...
« Reply #5 on: December 03, 2013, 08:44:58 am »
Just normal looking combustion crud.
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Offline Vinhead1957

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Re: I've been inside an engine before, I assume this is bad...
« Reply #6 on: December 03, 2013, 09:55:17 am »
I agree doesn't look too bad.   You have it off a good valve job is worth doing anyway.


Offline ncstatecamp

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Re: I've been inside an engine before, I assume this is bad...
« Reply #7 on: December 03, 2013, 10:54:35 am »
O alright then, just looked crudier then I was expecting. So i saw a thing in some manual I downloaded that said I should fill each valve (spring side I believe) with a solvent and see which is leaking. I was planning on lapping valves anyway.

To clean these up after I soaked them in a small bucket (keeping them labeled for location) in oven cleaner or something, I saw a video showing using a drill and a scotchbrit to polish em up a bit and remove crud. Is this a good idea? The video was made by motion pro and name brand stuff....

Offline MRieck

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Re: I've been inside an engine before, I assume this is bad...
« Reply #8 on: December 03, 2013, 02:24:42 pm »
I'd be more concerned about how the tips look...they are usually shot (especially on an older head like the one you you have). I am sure there is a good amount of pitting and erosion on the valve faces....you can lap them all you want but it still won't seal well. If you want to really test seal take it to a shop and have it vacuum tested on the Serdi....I think you will be very surprised at the results.
« Last Edit: December 03, 2013, 02:28:19 pm by MRieck »
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Offline ncstatecamp

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Re: I've been inside an engine before, I assume this is bad...
« Reply #9 on: December 03, 2013, 02:46:42 pm »


Any idea what this crap is? It's below the gasket surface for the jugs. Theirs no vent to the and it's packed kinda firmly.

Offline Jasondo

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Re: I've been inside an engine before, I assume this is bad...
« Reply #10 on: December 03, 2013, 04:02:42 pm »
looks ok to me. soak the valves overnight in oven cleaner. they will look good as new

Offline MoMo

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Re: I've been inside an engine before, I assume this is bad...
« Reply #11 on: December 03, 2013, 04:26:03 pm »
it sure looks like blue silicon sealant, and that is not good...Larry

Offline ncstatecamp

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Re: I've been inside an engine before, I assume this is bad...
« Reply #12 on: December 03, 2013, 09:54:25 pm »
It feels gritty like sand or dirt. No spring or goopy feel like silicon.

Offline bjbuchanan

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Re: I've been inside an engine before, I assume this is bad...
« Reply #13 on: December 04, 2013, 09:58:00 am »
My engine had heavy grit there too. I think that leakers accumulate there
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