Thanks for your input, the mac valve is located on the firewall above the genset.
No worries about crawling under the rig. Still having a hard time locating the mac valve (is it discontinued?
Pulled all the hoses off and sprayed ports. Don't know if it helped Has anyone had experience with substituting a Humphery Valve.
Again The mac valve is a 4 port unit 45A-AA2-DDCA-1BA. And the Humphrey Valve D1052 from NWRV Supply.
Thx,
Dan