need high idle to shift without killing engine volvo penta 4.3 gl with cobra sx

Grendel Nut

Cadet
Joined
Oct 9, 2014
Messages
8
My boat is a 1998 Four Winns 180 RS with a Volvo Penta 4.3 GL and Cobra SX out drive. Motor runs well and will do 53mph on GPS with 2 people on board.
Idles well at 650 rpm but can't shift into forward or reverse without killing engine unless idled up to 1400 rpm. Shifts fairly easily. Changed lower unit oil.
Help please..
 

Sparkinator

Chief Petty Officer
Joined
Aug 15, 2009
Messages
423
Are you sure your tach is correct? It's hard to believe it would shift smoothly at 1400 rpm. Mine would be slamming into gear at that rpm.

A while back, my shift cable was in need of replacing, and when shifting into gear, the engine would rev up before shifting. It would be less than a 1000 rpm and it would hit hard when shifting.
 

Grendel Nut

Cadet
Joined
Oct 9, 2014
Messages
8
Yes it slams. By smooth shifts I was referring to the control mechanics. My issue is the engine dies at lower rpms when engaging forward or reverse. I was thinking maybe something in out drive or gimbal bearings, but there is no unusual noise from the out drive and the boat runs well..
 

skydiveD30571

Lieutenant Junior Grade
Joined
Feb 13, 2012
Messages
1,042
You might want to get a tach reader and manually set the idle speed. I had a lot of trouble because my tach gauge was off so what I thought was 700-800 rpm was actually less....enough to cause a stall when shifting.

http://www.lightinthebox.com/profes...367773845352&gclid=CMjSwbW44sYCFUcXHwod5MEPDw

I bought one of these cheapies and put a small piece of the reflective tape on the circulation pump pulley. Went to the middle of the lake, made sure engine was at operating temp because that does make a good difference, put it in forward idle, and adjusted the carb until the laser tach read 600-650rpm. It's been great ever since.
 
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