Idle / shift problem 1978 1150 IL6

pfoley

Seaman
Joined
Mar 19, 2006
Messages
52
I was having problems at idle. When I would put the motor in gear, it would die. I did a decarb, and turned the idle stop screw 1 and 1/4 turns bringing up the idle speed a little.<br /><br />Put the boat in the water, pumped the ball, and she fired right up. It idled a lot better, and allowed me to put it in gear without it dieing so off I went. She ran great through the no wake zone and really ran well at full speed. At out 4000 rpms, however, it felt like the speed was surging a little. I didn't notice that at low speed or full speed incidentally. <br /><br />When I got near the dock, I slowed the boat way down, and pulled it into neutral. It died. The only way it would start again was with the fast idle all the way up. When I would try to bring it into gear it would die immediately. My idle problem is back! After a few frustrating minutes, I squeezed the ball and it was a liitle soft. Once it was hard again, I tried to start the motor and it started right up, and allowed me to put it into gear (coincidence?). On the trailer it went.<br /><br />Okay, the question: Is this likely a fuel pump issue, electrical, or maybe a float problem in the carbs? It's a new gas tank, ball, and connection by the way. And the vent was wide open on the tank ( I know somebody was going to ask me that!)<br /><br />The fact that it runs so well and is so powerful at wide open throttle, makes this extremely confusing for a novice like me.<br /><br />What's next?
 

MercFan

Petty Officer 1st Class
Joined
Dec 31, 2005
Messages
347
Re: Idle / shift problem 1978 1150 IL6

I'd say fuel pumps (Diaphrams and non-returns)
 

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Idle / shift problem 1978 1150 IL6

Pumps and maybe a idle mixture problem but the engine should be turning 54 to 5600 RPM at WOT and that will give a shift - idle problem also
 

pfoley

Seaman
Joined
Mar 19, 2006
Messages
52
Re: Idle / shift problem 1978 1150 IL6

Thanks for the replies:<br /><br />How many pumps do I have? What do I need to do to fix them? Rebuild kit maybe? Would a bad pump allow the pump ball to soften over time?<br /><br />Laddies, I'm not sure what you mean about the rpms. At WOT it runs very very well. My tach says 6000+ rpms, but I don't believe it. It shows 1800 rpms when the motor is turned off. It sounds and feels normal anyway! At around 4000 rpms it surges a little, and at idle it has a promblem too. What are you saying will give it a shift/idle problem?<br /><br />Thanks again for your help!
 

roger3645

Petty Officer 1st Class
Joined
Aug 30, 2005
Messages
271
Re: Idle / shift problem 1978 1150 IL6

You need to post some info on the motor. Hp year and serial number would help. I'd also say fuel pump. You could have someone squeez the ball while at WOT if this helps then it's fuel pump.
 

pfoley

Seaman
Joined
Mar 19, 2006
Messages
52
Re: Idle / shift problem 1978 1150 IL6

Roger, it's a 76- 78 1150 I6. I dont have the serial number handy unfortunately. At WOT it runs perfectly, so I'm not sure what squeezing the ball will do at that point. Your help is appreciated.
 

pfoley

Seaman
Joined
Mar 19, 2006
Messages
52
Re: Idle / shift problem 1978 1150 IL6

I'm adding this comment in hopes of moving it back to the top of the page before it disappears. Is anyone else familiar with the problem I'm having?<br /><br />Thanks.
 
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