1978 mercury 700 3cyl oil/gas ratios

[joe belcastro]

Hi, back again. I am getting a little confused on my oil to gas ratios for my 1978 mercury 700 3cyl 70hp. I have read 50:1 36:1 and 24:1 ratios. My problem is the motor runs great in nuetral and bogs down in gear. Sometimes it will run good and other times it just bogs dow. I changed the bubble and gas line to the motor, the fuel filter is clean and the plugs don't look fouled. I checked the vent cap on the gas tank and it looks ok. When I put it in gear it runs like it's flooded? In neutral with the throttle wide opn the motor smokes, at idle no smoking. Any help or suggstions would be appreciated. Thanks<br />in advance.

 

[chrbartlett]

Re: 1978 mercury 700 3cyl oil/gas ratios

what type of oil are you using? cheap/expensive

 

[joe belcastro]

Re: 1978 mercury 700 3cyl oil/gas ratios

using tcw3 super tech (wal mart brand)

 

[JB]

Re: 1978 mercury 700 3cyl oil/gas ratios

Are you using 50:1, joeb? <br /><br />That is what you should be using.

 

[joe belcastro]

Re: 1978 mercury 700 3cyl oil/gas ratios

50:1 mixture; however further investigation and I found no spark at all on any cylinders. I found 4 wires coming from the ignition harness with corroded insulation and frayed exposed copper. wires go to starter solinoid and switch box. Motor will not start now. What a mess hope I can buy a premaid harness from mercury. Thanks for all the help, I hope replacing or repairing the harness fixes everything.<br /><br />Thanks again.

 

[timmathis]

Re: 1978 mercury 700 3cyl oil/gas ratios

Good Luck.