1975 7.5 Merc low power in forward but full power in reverse.

[bobpatterson]

I recently added five feet to the fuel line so I could move the tank more forward but I don't think this is the problem as I get full power in reverse but it's just doggy in forward. I replaced the plugs. Help!

 

[JB]

Re: 1975 7.5 Merc low power in forward but full power in reverse.

Hi, Bob.

Welcome to iboats.

I suspect that you are getting low output from your powerhead which just appears full in Reverse because of the much lower gearing.

First, be sure that the throttle is opening all the way in FWD (it should be limited in Rev).

After assuring that both cylinders are making power, do a link 'n' synch by the book.

Let us know the outcome, and good luck.

 

[bobpatterson]

Re: 1975 7.5 Merc low power in forward but full power in reverse.

Thanks for the reply, but, please let me try to clarify my question. This motor ran perfectly until now. In forward it runs slower than my elec. trolling motor goes. I could probably ROW faster! When I put it in reverse it revs up fine as normal. (Really screams!) Would it not rev it both directions the same without a "powerhead" problem gear ratios beside the point? Both plugs appear normal. Could this be an overly rich gas to oil mixture problem? Since I don't have the manual, can you tell me where I mught find the forward speed detent or whatever?

 

[simeon1949]

With my 7.5 I'm getting the same issue, but with mine in a barrel it revs up just fine. In the warer I can go faster in rev than in forward. It goes like half throttle.

 

[racerone]

Maybe your motor is only running on one cylinder.---Bad spark on one or compression problems.----In a barrel in reverse there is lots of exhaust and very little load on the prop.

 

[simeon1949]

Reverse and forward in a barrel both act the same, which is, full RPMs On the water reverse acts the same as in the barrel, but forward only gives app. half throttle. Linkage is traveling to full throttle?? In all situations motor runs very smooth. Trolling for a couple of ours without so much as a hiccup?