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Helpful ReplyHot!New valves

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Harold73521
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2017/09/19 16:27:14 (permalink)
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New valves

I just replaced new valves in a B&S engine. Now I don't have any compression. What did I do wrong? Thanks.
Gregb7
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Re: New valves 2017/09/19 17:00:18 (permalink) ☄ Helpfulby Harold73521 2017/09/19 22:19:42
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Are they seating all the way against the valve seat? Did you reuse old headgasket or replace with a new one?
AVB
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Re: New valves 2017/09/19 18:34:32 (permalink)
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Please post your engine numbers so we all can be on the same page.
 
But Gregb7 suggests check your valve clearances even L-heads some need to have the clearances adjusted when new valves are installed.
 
Harold73521
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Re: New valves 2017/09/19 22:18:20 (permalink)
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 B&S engine 135292/0158-01 Fully disassembled and replaced woodruff key on timing gear. After reassembling had hard kick back. Thought I might have missed  getting cam and timing dot right. Removed crankcase cover and was right, dots matched. I decided maybe valve caused the kick back. Replaced them with new, all new gaskets. Looked to be opening and closing as they should.
post edited by Harold73521 - 2017/09/20 06:58:17
Roy
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Re: New valves 2017/09/20 10:39:56 (permalink)
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What are your valve clearances? Should be .005"-.007 INT and .009"-.011" EX
Harold73521
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Re: New valves 2017/09/20 13:42:59 (permalink)
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Thanks Roy,  I check and let you know. If the clearances are off, how do I adjust? Guess that would be closed?
post edited by Harold73521 - 2017/09/20 15:26:51
Mikel1
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Re: New valves 2017/09/21 09:55:10 (permalink)
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Looks like flathead/L head, horizontal shaft. I would go ahead and pull head. Roll it around to TDC compression stroke then rotate 1/4" down on piston, both valves should be closed. Then check the clearances like the members have suggested. You can file down the stem if clearance is too tight.
AVB
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Re: New valves 2017/09/21 10:58:59 (permalink)
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If you do need open up the clearances. When you file you will to remove the valve, lightly file squarely, temporary re-install the valve and all while checking the clearance very often as it is easy to over do it quickly.
Harold73521
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Re: New valves 2017/10/12 10:00:02 (permalink)
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  Ok got he valves filed, engine reassembled, and can't get it started. It has a hard kickback, so I'm guessing something is out of time.  New key on fly wheel, old one looked fine but just to remove any doubt  New key on timming gear, dot on cam matched. I'm at wits end. Any help is much appreciated, and thanks for all previous post.
Roy
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Re: New valves 2017/10/12 11:32:54 (permalink)
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My guess is you checked the valve clearances at the top of the exhaust stroke. Rotate the flywheel a full revolution and check again.
Harold73521
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Re: New valves 2017/10/12 16:20:42 (permalink)
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Mike11 said " Rotate to TDC on compression stroke then pass to 1/4 inch down." I tried several positions finding the largest gap possible.
 The only thing I didn't do was replace the top retainer on the exhaust.  Couldn't figure a way to replace it.  With the valve spring tool  and both retainers the valve shaft would not lineup. In other words with both retainers and spring in the tool I could stick the shaft through but couldn't compress the spring.
 
 
 
 
AVB
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Re: New valves 2017/10/12 16:54:33 (permalink)
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Assembly error... Both the valve spring seat and valve retainer don't go on the same end.
 
See APSI 25 below.
https://drive.google.com/...pKUJnh7ejlnTHpMVlJWTzA
Harold73521
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Re: New valves 2017/10/13 10:26:04 (permalink)
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Thanks AVP! I was trying to install the retainers in the correct position. I was trying to use the tool.  Thanks for the helpful link. I will try that. That makes sense to not put the top retainer in the tool.
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