79 70hp seahorse slight bog upon accel and idle issue

[Gulfhorse]

The carbs have been cleaned and fuel lines replaced. The bog seems to be getting less and less but still aggravaiting. It only bogs for just a few seconds and will work it self through the bad spot and then comes alive. If all is well with the carbs could it be the timming is off? Thanks for any input.

 

[oldcatamount]

Re: 79 70hp seahorse slight bog upon accel and idle issue

That doesn't sound like an ignition issue to me. Are you running fresh fuel? Could it have some water in it? If it were ignition related, it wouldn't be getting "less and less" by itself. Sounds more like a fuel delivery issue, maybe a fuel tank vent is going bad on ya.

 

[Gulfhorse]

Re: 79 70hp seahorse slight bog upon accel and idle issue

It has new gas and filters. I cleaned the carbs lastnight. however the problem got a little better, but my thouhts are that it is acting like a car that has the timing not set just right. It will rev while in nuetral just fine however when in gear and accelerating, it wants to bog until it works through the bad spot (for lack of better words). Do you or anyone know if adjusting the linkage that adv/retards the timing may clear up this issue. Thanks alot.

 

[oldcatamount]

Re: 79 70hp seahorse slight bog upon accel and idle issue

Your motor has electronic ignition and there is no timing adjustment other than what is called a "Synch and Link" where you adjust the throttle linkage so that the throttle cam roller reaches the hash mark on the timing plate at the same time the throttle plates in the carbs start to open when you are advancing the throttle. It's important that both carbs are adjusted exactly alike.

 

[jtexas]

Re: 79 70hp seahorse slight bog upon accel and idle issue

Tries to bog but you can nurse it up to WOT -- couple things I know of will cause that (apart from dirty carbs): idle speed set too low, and throttle valves opening too soon, before the spark is advanced enough. And maybe a sticky timer base. That's three things.
Set the idle speed to around 800 in gear, in the water. On the muffs, set it to around 1000 then fine-tune it in the water.
Make sure the timer base moves smoothly without sticking, and the cam roller hits the mark when you advance the throttle (see pic).

If that doesn't do it, you'll want to do a full link & sync, best to have a manual for the step-by-step.

 

[Gulfhorse]

Re: 79 70hp seahorse slight bog upon accel and idle issue

Thanks alot for the suggestions. I will keep everone updated on my results and what helped and didnt help. Could any one give me the elementary version of a link and sync. I have order a oem manual however, felt it would be helpful to here it in plain english from guys who have performed such adjustments..Thanks again everyone

 

[jtexas]

Re: 79 70hp seahorse slight bog upon accel and idle issue

The main points of the link & sync procedure are 1> to have all 3 throttle butterflies closed at idle, parallel throughout their range of motion, and horizontal (not beyond) at WOT; 2> spark timing correctly advanced when the throttles start to open; 3> idle speed correctly set.

#2 is accomplished by setting the roller to where it hits the cam right on the mark (see my previous post). If the idle set screw is butted up against its stop and the motor is idling at about 1000 (on the muffs), #3 is done. When you put the motor in the water, backpressure on the exhaust will lower the idle speed. Fine tune it to around 750-800 in gear in the water.

In my experience, if all you did was rebuild the carbs, they usually go back on just like they came off and may need very slight adjustments, or none at all.

 

[Gulfhorse]

Re: 79 70hp seahorse slight bog upon accel and idle issue

well I installed new needle and seats in all 3 carbs and the bog seem to get better however still present. I figure the next step to take without spending any more money id to link and sync. Does it sound like this issue could be solved by a link and sync? I let you know my results soon.

 

[boobie]

Re: 79 70hp seahorse slight bog upon accel and idle issue

When this bog happens did you ever "hit" your choke and see what happens? If it picks up that will indicate if something in the system is running to lean.

 

[Gulfhorse]

Re: 79 70hp seahorse slight bog upon accel and idle issue

No, I can't say that i have. I feel pretty sure that this would just flood the motor, however you may have a valid point. From looking at the plugs, i would say the motor is not having a problem with fuel since i have installed new needle and seats.