idle problem/power loss

[jacob_smith14]

Hey everyone, I have a 1983 Johnson 150 V6 that had been running great until about last week. <br /><br />Have to start with engine in neutral and throttle high. After dropping to idle the engine dies. After letting it run for 5 plus minutes can have it sit in idle but when you shift into gear the engine dies again. <br /><br />Before this happened I experienced a loss of power and was unable to get back on plane and maxed out around 3000 rpms. <br /><br />Checked the fuel filters, fuel lines and spark plugs. I am new to boating and far from a mechanic. Had someone suggest it may be a power pack. Any way to test? Any other ideas? Thanks!

 

[The Marine Doctor]

Re: idle problem/power loss

Do a compression test and also check for spark on all cyl's.<br /><br />TMD

 

[marinegrh]

Re: idle problem/power loss

have you a shift switch, ties into the power pack, are you running on all 6 cylinders, might be a good time to check spark and compression, you should pick a service manual at you local marine dealer

 

[jacob_smith14]

Re: idle problem/power loss

Im going to test compression this weekend. What should the readout be?

 

[rickdb1boat]

Re: idle problem/power loss

at least 100 PSI and more importantly, even on all cylinders. Check for spark as suggested. Could just be an electrical failure. Better than the alternative!

 

[jacob_smith14]

Re: idle problem/power loss

Im going to test compression this weekend. What should the readout be?

 

[jacob_smith14]

Re: idle problem/power loss

Thanks for all the help. Checked the compression on the engine and 2 consecutive cylinders had a reading of 30. Took of the top part of the engine and found a blown head gasket. No damage to the cylinders either. Replaced the head gasket (23 bucks) and borrowed a torque wrench to get everything back in place. Engine runs great!

 

[whofan]

Re: idle problem/power loss

Good deal! thanks for sharing your fix. Helps us all out.