Older hi ranger cycling too quickly

[Luztree]

I have a 1988 hi ranger 5hi and its cycling too quickly. Is it just low on nitrogen or a bad valve. I'm in central New Jersey. Anyone recommend a mobile guy or a close repair shop? I'm in the colts neck n.j. area. Central jersey 20 minutes from ocean

 

[Luztree]

I have a 1988 hi ranger 5hi and its cycling too quickly. Is it just low on nitrogen or a bad valve. I'm in central New Jersey. Anyone recommend a mobile guy or a close repair shop? I'm in the colts neck n.j. area. Central jersey 20 minutes from ocean

Anyone?