Tohatsu 70c questions

[Texastoon]

I picked up a pontoon with a 70 on it and finally got out to the lake with it today. I should mention that the person I bought it from had let it sit up for a couple of years.
Starts and idles with throttle lever fine, and a bit after fully closing the idle lever. When in gear under a load it runs up to 2500 or 3000 rpm and that's all. Very sluggish and then starts to be more sluggish. Took off engine cover and noticed when idling and revving a little manually a small back fire on the bottom cylinder on the side of the motor with all the linkage. Back behind the carbs in the middle of the engine. Almost like a backfire on the side of the motor when idling down or on the way down to just idle.
Any thoughts or ideas.
Thanks

 

[pvanv]

Re: Tohatsu 70c questions

Probably an exhaust leak from a bad base gasket.

 

[Texastoon]

Re: Tohatsu 70c questions

I think I might have found the problem. I finally got a chance to take a look at the motor and found a rubber line off of a brass nipple on the side of the motor that runs around to the front to another nipple that wasn't connect.
There was another line just like it above and running to same area connected to the same type of nipple. Some type of vaccum i guess? Any way, started after connect and runs and idles fine now. Have to wait until the rain passes to put it on the water for a test under load.

I bought some stuff from iboats and have a question.....maybe someone will catch it here.
I got a filter/water seperator....... sierra brand. How often should I change that filter?