# YM1610 Problem



## jon_s (Jun 15, 2009)

My YM1610 has developed a problem - grateful for advice on diagnosis. I think it may be the cylinder head gasket

Symptoms:
Getting quite warm, but temperature gage doesn't go into the red and no warning light. Excessive amounty of coolant from radiator moves into the overflow bottle (spills out of the top) when the tractor heats up. Doesn't return when the tractor cools, leaving the level or coolant in the radiator low. Pressure build up in the radiator which doesn't diasappear when the tractor is cold (the next day there is still a a hiss when you take off the radiator cap). I have replaced the radiator cap with same spec (0.9bar) with no effect. There is the appearance of bubbles in the coolant in the radiator when the engine is running - not sure about this as it could just be caused by the vibration. No appearance of white smoke, but a small amount of black smoke on start-up and when revs are significantly increased. No oil in coolant and no coolant in the oil.

I'd appreciate advice on what it is or may be that's causing this problem.

Jon


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## SHARTEL (Feb 11, 2009)

Hi Jon, and WELCOME to TF!

If you see bubbles in the radiator neck it’s almost certain you’ve developed a blown head gasket and maybe a hairline crack in the cylinder head. It IS a rather simple fix by changing the head gasket and having your head examined (LOL) for warpage and cracks. It does NOT sound as though your YM1610 got hot enough to do any head damage IMO.

If the fan belt is tight then check for pump play. If you reach in (while the engine is NOT running of course) and grab the fan blades to check for end play or wobble and get any significant amount, it’s time for a water pump replacement. If it’s ok, then:

The cause is almost always radiator cooling tubes filled with silt! Japanese rice farmers have no guilt about dipping into the dirty paddy waters and topping off their overflow bottle. A new or Re-core or rotting out the radiator will immediately drop the 212°-230° operating temperatures down to 170°-185° under medium load…and only slightly higer during heavy operation during the summer months. It’s also a good time to replace the upper, lower and bypass hoses on your machine. I can’t count how many radiators I’ve replaced in the last five years (5 or 6 maybe)…but it is the permanent fix and your tractor is ready to go for another 30 years.

Hope this helps.

SHARTEL


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## jon_s (Jun 15, 2009)

Shartel,

Many thanks for the great advice - much appreciated.

Jon


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