how can i test john deere b manifold

grampsh1 · May 24, 2017

my b will run for about 2 minutes reasonbly well then falters for another minute carb and intake create a lot of cold water on outside then will finally quit changed out carb today with a dtlx 71 off my styled a r and changed mag with good hot mag off my b r will run if hold hand over inlet regulating air but stalls when try to increase rpm with throttle I am suspecting a crack between intake and right exhaust side of manifold as carbon build up on inside intake against exhaust side of manifold no vacuum to pickup fuel and will fire back through carb when trying to restart when warmed up any suggestions manifold gasket looks good

Steve@Advance · May 24, 2017

That sounds more like a fuel restriction to the carb. Check the flow to and through the carb. If there is a drain plug on the carb, remove it with the fuel valve open, should get a full flow. If it slows to a drip or stops, there is not enough fuel getting to the carb.

A burned through manifold typically will run better at high RPM and worse at idle. If it will idle good, that's not the problem.

The cold water is condensation, that happens because the fuel being drawn into the engine is vaporizing (as it should) and cooling the intake.

grampsh1 · May 24, 2017

thanks steve have had carb apart cleaned in carb cleaner brass screws removed and all passages cleaned fuel nozzle removed and cleaned put a barb in bottom of bowl with clear tubing and brought up side of bowl to check float level and maintaining level when running lots of fuel flow when tubing dropped below bowl level fuel not draughting going to remove bowl and check fuel nozzle in place properly willing to try anything at this point have checked valve adjustment timing is bang on intake valves not sticking lots of oil to exhaust valve

how can i test john deere b manifold

grampsh1

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Steve@Advance

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grampsh1

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