1984 3.7 Mercrusier 470 another hot start issue

[a1nowell]

Re: 1984 3.7 Mercrusier 470 another hot start issue

Have you starter rebuilt. Then you know what your getting. Also, give some thought to switching to electronic ignition.

Larry

 

[carguy001]

Re: 1984 3.7 Mercrusier 470 another hot start issue

thanks, i was going to call the local rebuild shop first, i am little unsure about buying a reman

 

[fmalott]

Re: 1984 3.7 Mercrusier 470 another hot start issue

I have now cleaned and lubed the counter weights everything seemed to be in good working order there. i put everything back together set the points gap to .024" and the dwell was @ 31 degrees. 4-5 revs and fired up set the idle to about 750 rpm and set the timing to 5 degrees. boat idled well reved up to 2000 rpm nice let it run about 15 mins shut it off waited about 2 mins fired right up let run for about 5 mins shut it off and let it sit for about 15 mins cranked about 4-5 revs then started cranking slow. waited about 2 mins still cranked slow no start. guess i am going to try a new starter. found a reman for 95.00

point gap is .022 on a 470 not .024 and timing is 4 degrees BTDC

 

[stonyloam]

Re: 1984 3.7 Mercrusier 470 another hot start issue

point gap is .022 on a 470 not .024 and timing is 4 degrees BTDC

Dwell (the number of degrees of rotation that the points are closed) is the critical reading not gap, because ware on the cam lobes can change the gap needed to get the proper dwell reading.

 

[carguy001]

Re: 1984 3.7 Mercrusier 470 another hot start issue

well spoke to a guy today from a local marina shop and he gave some things to try 1) wrap the fuel line in isulation. i did that. 2) check the float level and reset it to the spec sheet or about 1/16" lower than the spec. when i took the carb apart there was only about a 1/2" of fuel in the float bowl and the float was about 3/16" lower than the spec, i must of bumped it last time i had it apart. 3) replace the thermostat with a 153 degree vs the 160 degree he said it should lower the temp by about 12 degrees. have not done this yet due to no stat in stock.

but i got the motor up to temp and shut it off and was able to get it started after 15 mins of sitting with cracking the throttle 1/4 way open and about 3-4 revs in fired up. i did the same thing again let in run about 20 mins and shut it off letting it sit for 15 mins and started the same way. but let it for 30 mins and it seemed flooded but cranked strong tonight and almost started but it was 10pm so i quit for the night. i am hoping the therostat fixes it


thanks for all ideas and replys

scott

 

[carguy001]

Re: 1984 3.7 Mercrusier 470 another hot start issue

Well after all this it ended up being a bad starter it finally just quit cranking and was screaming hot to touch.

 

[carguy001]

Re: 1984 3.7 Mercrusier 470 another hot start issue

got the new starter and installed it solved the issue, tore the old stater apart and found the bindix stuck out (engaged),the internal spline of the bindix was striped, the armature had some nice size chunks in it, the commuter end was shorted out. the only thing that was in ok shape was the outside body.

thanks again for all the help

scott