175 Mercury Blax Max idle/timing adjustment

[Yostie]

I have an 88 hydra-sports boat with 175 merc. black max. The last day of use in Aug. the idle increased along with a shift problem..... It has a hot foot gas pedal installed.. I adjusted what I thought was idle adjustment screw but may have changed the timing since it got hot yesterday at wot. I noticed that one adjustment screw was not touching the stop.. But there are several adjustable screws on the side of the engine.. Is there a diagram somewhere showing the adjustment screws and their functions???
Also my shifter does not have definite forward,N, and reverse like it did before... Finding netural is hard, when you pull it out of forward it doesn't click into N it will go on to Reverse?? Could the fast idle and shift problems be related ?? ANY help is appreciated !! Fish are bitin and my boat is sick.......... Many Many Thanks

 

[Laddies]

Re: 175 Mercury Blax Max idle/timing adjustment

Quit tinkering with it before you trash it go buy a OEM manual and do it properly

 

[j_martin]

Re: 175 Mercury Blax Max idle/timing adjustment

Like laddies said.

 

[Yostie]

Re: 175 Mercury Blax Max idle/timing adjustment

Gee Thanks !!!!! what useful advice... A manual huh ? Who would've thunk it ? A book to help with a problem.. wow! Thank you for your time ..
Happy New Year !!!!

 

[j_martin]

Re: 175 Mercury Blax Max idle/timing adjustment

Gee Thanks !!!!! what useful advice... A manual huh ? Who would've thunk it ? A book to help with a problem.. wow! Thank you for your time ..
Happy New Year !!!!

Yostie,
Never mind, don't get a book.

A two degree error in timing can make total scrap out of your motor in less than 10 seconds. Go for it, you know it all. It'll never happen to you.

FYI, there are many different Link and Sync (Linkage, timing, and syncronization) scenarios for V6 Mercury engines. If you get the book and do the procedure, and it doesn't come out like it should, you have a serious mechanical problem. The first step is the Link n Sync.

There ain't no free lunch, and no quick fix. I ain't about to try to help someone who insists in being ignorant wreck his engine by suggesting there is such a quick fix.

hope it helps
John

 

[hkeiner]

Re: 175 Mercury Blax Max idle/timing adjustment

Gee Thanks !!!!! what useful advice... A manual huh ? Who would've thunk it ? A book to help with a problem.. wow! Thank you for your time ..

You got very useful advice. Your not knowing that it was very useful advice makes the advice even more useful to you...

 

[Yostie]

Re: 175 Mercury Blax Max idle/timing adjustment

Sincere Thanks J Martin That's the information I was hoping to get from my first post.. Had already done the obvious, and had a manual on the way.. Was unaware that the adjustments were so extremely sensitive.. I am somewhat impatient but not ignorant.. engine is probably toast now anyway, guess I'll find out when manual arrives

 

[j_martin]

Re: 175 Mercury Blax Max idle/timing adjustment

Sincere Thanks J Martin That's the information I was hoping to get from my first post.. Had already done the obvious, and had a manual on the way.. Was unaware that the adjustments were so extremely sensitive.. I am somewhat impatient but not ignorant.. engine is probably toast now anyway, guess I'll find out when manual arrives

When you get the book and learn how all that junk on the port side of the engine relates, you can maybe just back off what you did and go from there in troubleshooting mode.

Odds are, judging from what you said in the original post, it's a problem with the hotfoot or the cable to it. I noticed Gander Mountain carries one model of the Hotfoot, and a replacement return spring for it. (in stock)

Idle speed is mostly controlled by timing. The idle stop screw should hit the stop every time. If it doesn't it's a cable or control problem. The next thing in the sequence is the cam picking up the throttle linkage. Both idle timing and throttle pickup timing vary from model to model. That's where the book comes in.

If everything is timed right, and your compression is good, odds are you broke a bleed line or have something loose in the front end that's letting in air. It'll toast the motor in short order if that's the problem and it's not fixed.

(edit) Just came to mind, if you have an idle stabilizer module on it, and it shorts out bias to ground, idle will speed up, and so will max timing. (destruction in short order)

These engines aren't very complicated, but they normally run on the hairy edge of self destruction, so small things can turn into big problems pretty quickly.

hope it helps
John