Mariner 175 no power under load

[wcarmstrong]

From Mercury OEM factory service manual for 1978 175hp with Mercury OEM stator: Disconnect blue/white and red/white stator leads from outer switch box and blue and red stator leads form inner switch box. With scale reading set at R x 1000: Test leads - Between Blue and Red Stator leads ohms should be 5.4 - 6.2. Between Blue/white and Red/white stator leads ohms should be 5.4 - 6.2. With scale set at R x 1: Between Red stator lead and engine ground ohms should be 125 - 175. Between Red/white stator lead and engine ground ohms should be between 125 -175. If stator has black ground wire, make sure black wire is grounded to engine. Stators with part # 398-5454A34 should indicate 65 to 75 ohms between Red or Red/white stator leads to engine ground. Stators with part # 398-5454A34 should indicate 4450 to 4650 ohms between Blue and Red stator leads and between Blue/white and Red/white stator leads. Hope this helps.

Between blue and red - 6.2, Blue/wht stripe and Red/wht stripe - 6.2, Red to ground - 141, Red/wht to ground - 140. Everything appears to be in range. I really appreciate you posting this. Gives me additional confidence that the swith boxes were the cause. New ones from CDI came in today and Im just finishing the installation. One of the two failed the bench test, so it definitely needed to be replaced.

[wcarmstrong]

Well it was definitely the switch boxes. Finally got to take it out over the weekend and it ran beautifully. Still have a lot of work to do with the setup, but she launched out of the hole and I hit 50 mph gps without even pushing her hard. It was around 30 degrees out, and I didn't have my helmet on, so I was limited in how much I wanted to run it, but suffice it to say, getting over 2000 rpms is no longer an issue! Thanks for everyone that contributed to this thread. Your input was extremely helpful.

[OnTRAK]

Cool. Glad you got it worked out.