Very little Power in Forward Plenty in Reverse

[JosephACavin]

The Strangest thing, I have an old 1970 1350 Merc with Thunderbolt ignition and if I put it in reverse it has loads of power but in forward it is like running a 15 horse it will not run wide open. Anyone have any ideas?

 

[Chris1956]

Re: Very little Power in Forward Plenty in Reverse

Joseph, There is no inherent reason for the motor to do that. Are the throttle plates (butterflys) full open (engine off, throttle in fwd, at full )? if so it wuld appear that either it is a complete mystery, or......

 

[studlymandingo]

Re: Very little Power in Forward Plenty in Reverse

Yes it does seem like a possible cable issue. Is it bogging, or just not taking throttle?

I guess you could get a left-handed prop and just run her in reverse! (Just Kidding!)​

 

[Yepblaze]

Re: Very little Power in Forward Plenty in Reverse

I bought a boat like that once......


The shift cam in the lower unit was put in upside down, and most every other thing was done trying to correct it. So even though the controller was pushed forward the cable arrangement allowed the mechanism to run up on the reverse idle speed stop, and wouldn't go fast in forward....... or was it reverse.

 

[JosephACavin]

Re: Very little Power in Forward Plenty in Reverse

When I push the controller all the way forward it will cut off. I checked the controller and all seems fine inside. It does seem that the distributor does move more in reverse than forward. I am really stumped on this one. The cables are the way they have been for over 15 years and nothing has been done to them. The guy I bought the boat from said it used to run wide open. but it got where it would only run for about 20 minutes and then cut off. It runs fine for me but it just will not open up. If I can't figure this out I am a no go show boat.

 

[Clams Canino]

Re: Very little Power in Forward Plenty in Reverse

See my timing and synch post in the FAQ - and run through that.

That's the 1st step.....

-W