3.7L, 4cyl., merc470 bog, want to rebuild carb

[boatforever]

I have a 1987 Sunbird with the 4 cylinder 3.7L, 165hp, merc470 engine, the carb has the tag saying MCM 165, 1389-9564.

I just started to the use the boat for the first time. The engine runs great at WOT and it idles ok, (I think I am have an exhaust leak). But when I have a tuber or a skiier on the back i had the engine stall on me twice. I raised the idle and the boat performed worse. I have to feather the gas in order to get the engine into RPM, once the engine is at rpm then it runs fine. When I slowly increase the throttle I have no problems, just when I want to pop a skiier out of the water is when I have the problems.

I read a merc sercive bulliten on this issue. Merc says to replace the acceralator pump with a new and improved part number.

I was going to rebuild the carb with this Sierra P/N 18-7098. Does this kit use the new and improved pump kit, I would only assume that it does.

Are there any ticks or risk area's I should worry about during the rebuild. Does anyone else think it could anything else?

Thanks in Advance,
Shawn

 

[searay3]

Re: 3.7L, 4cyl., merc470 bog, want to rebuild carb

Typical of an accerlerator pump not working. Since you have to disassemble the carb to work on it, it is a good idea to rebuild the whole thing. It should all be in the kit. Be sure to blow all passages with compressed air prior to reassembly. Also, at that age, look carefully at the carb body. There can be deterioration of the carb body itself.

 

[Blk-n-Blu]

Re: 3.7L, 4cyl., merc470 bog, want to rebuild carb

Here is a link to a service manual:
http://www.boatfix.com/merc/Servmanl/13/13covr2.pdf
look here first:
http://www.sterndrives.com/check_carburetor.html
hope it helps.

 

[MrBill]

Re: 3.7L, 4cyl., merc470 bog, want to rebuild carb

Before rebuild just check the easy basics; timing, idle fuel mix. Takes ten minutes, is free, and might solve problem...then go in for the more heavy duty work.