IÃ‚Â’d been have a rough idle problem with my 1988 Johnson 175hp so I started looking at the recirculation system. I think there are 6 recirc valves -- 2 under each of the 3 carb pairs. I tested the valves according to the manual with a syringe of alcohol and they appear to be working correctly as a one way valves.
The recirc valve hoses are connect together in 2 groups of 3 with each group having a hose going to the manifold -- one port is between the top and middle carbs and the other between the middle and bottom carbs. The manual says the manifold ports should flow freely in and out using the syringe test. Both of mine are fully clogged. No flow either way. The manual shows a special tool to unclog them. IÃ‚Â’ve tried a fine wire which I can push in about an inch. IÃ‚Â’ve also tried carb cleaner and compressed air. No luck.
How do I unclog the manifold ports? Do I need to remove the intake? Instead of draining into the clogged manifold ports, could I just tee the recirc valve hoses into the front air intake cover drain hose that drains into the block?
Thanks for any advice.