B+S 318cc 8hp motor carb question.

trooper1954

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Hello all,
Have a very old John Deere rear engine mount R70 tractor/mower. It fires up so has spark....it has fresh fuel...gas lines and in-line filter are clean. Here's the problem.....it fires right up, runs for 10-15 secs and then dies. There is a pilot screw at the bottom of the float bowl.......it is fully home.....just wondering if this is the problem, and if so, how many turns should it be adjusted?
I have looked extensively on line for an owners manual but no luck....Unless I pay more than the mower's worth!!:confused2:
Any other problems I should troubleshoot?
Thanks
 

reynoldston

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It should be 1 1/2 to 2 turns out from bottoming out. Once the engine is running at WOT (wide open throttle) and warm readjust it till the engine is running at peck.
 

bertsmobile1

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That valve is the main jet,
Adjust as per instructed.
This carb has a starting circuit which sucks fuel in from a seperate hole , just enough to run the engine very slowly.
The instant the throttle opens up the tiny starting hole can not supply enough fuel and the engine stops.
 

trooper1954

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Thanks to both of you....adjusted out 11/2 turns and now runs fine.
Does anyone have any idea how to set up the mowing deck properly?....or links to an owner's manual?

Thank you so much for the help.
 

primerbulb120

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Visit this webpage: jdpc.deere.com/jdpc/servlet/com.deere.u90490.partscatalog.view.servlets.HomePageServlet_Alt

Put in your model number (R70), select "Sectional Index" and see if the diagrams are of any use.
 

trooper1954

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Visit this webpage: jdpc.deere.com/jdpc/servlet/com.deere.u90490.partscatalog.view.servlets.HomePageServlet_Alt

Put in your model number (R70), select "Sectional Index" and see if the diagrams are of any use.


Unfortunately, link returns a 404 error
 

trooper1954

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Thanks, but I was looking more for the owners manual....how to actually set up the deck for mowing rather than needing parts.
Appreciate the help tho....if anyone has a line on how to set up the deck, make sure it's level etc I'd be grateful.....never had a ride on before!:confused2::confused2::confused2:
 

BlazNT

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John Deere sales their user manuals. If you can get one for free it'll be in the link that the guy posted for you earlier.
 
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