125 hp slow cranking

[wlg]

Tried to do compression check on this motor. Fully charged battery and jumped directly off starter. Hesitates on rotation and have to stop at three rotations. Got 60 to 70 psi on each cylinder. With nothing in any plug hole, motor spins freely and seems to have good air flow against my hand on each cylinder.

What do I need to do?

 

[foodfisher]

Re: 125 hp slow cranking

Load test your battery. If it checks out, look at the starter motor.

 

[JB]

Re: 125 hp slow cranking

Do the compression test with the plugs out.

 

[wlg]

Re: 125 hp slow cranking

Problem was the battery.
Cylinders tested 100 to 103 psi each. This is just a cheap tester from HF.
I already purchased a new fuel pump kit and complete water pump. I am going to install and do other required maint. and try to get the motor running.

 

[foodfisher]

Re: 125 hp slow cranking

Fasten your seatbelt

 

[wlg]

Re: 125 hp slow cranking

foodfisher, Is that in a positive way? I repair things for a living, but feel in over my head on this. I can't afford to screw it up. Any oppinions or thoughts?

 

[foodfisher]

Re: 125 hp slow cranking

Yes, positively. Don't know your experiences with boats, but for me, I still haven't opened my '86 125hp all the way. It's just more than I'm comfortable with. On the side, is Summerdale anywhere near Carlisle, my place of birth? Try some of Franks snake oil aka Deep Creep and see if you can bring the PSI's up.

 

[wlg]

Re: 125 hp slow cranking

foodfisher, Summerdale is about 15 miles from Carlisle. I actually work in Carlisle on the Newville side about 25 miles from my home. Has it been awhile since you've been there?

I will look for the Deep Creep. How high have you had the RPM's? I was thinking it was more than i needed, but it's already on the boat. I also picked up an 85hp just in case.

 

[foodfisher]

Re: 125 hp slow cranking

Wow, Hi neighbor! Yes it's been awhile. Went back 30 yrs. ago for a family reunion. Left when I was eleven yrs. old. I'm 65 now and still can't shake the snow. Googled your place and liked the close proximity of the river. Is that the Yellow Britches or the ?Can I go in it?? Got family all over Boiling Springs and Mount Holly. OK, boats. I've had it pushing 5K w/33mph showing on the speedo. Too much for comfort on my resevoir. Don't know what another 5-6 hundred will do but it's nice to know it's there.

 

[wlg]

Re: 125 hp slow cranking

30 yrs. is a long time. The river is about a quarter mile from my house and the Can I go in it runs into that, also not far from the house. The creek is only good for floating or wading in most places. The river depends on location.

Put the new water pump on the new to me lower unit and installed on motor. Need to pick up some oil to change out the lower. Was thinking about trying to start the motor before installing the fuel pump kit. I know, I already have it so why not put it on? Guess that answers that!!

 

[foodfisher]

Re: 125 hp slow cranking

Try it. If it runs good you've got a new backup pump. I've got to catch the fall colors before they throw dirt in my face.