3 Honda bf8ah questions

Good morning all, i am in need of having these 3 questions answered please
#1- my motor gradually slowed down & then stopped peeing completely but is not hot to the touch so i replaced the impeller which had 3 cracked vanes but no pieces broken off. made no difference,water coming out of the exhaust but nothing from the pee tube. i then removed the two rubber water hoses which are open,ran a small plastic coated wire through the inlets but no debris so i thought that maybe it was the t-stat so i took the inlet manifold off & found that there was no t-stat in it So what next ? the motor is only warm to the touch after idling for 20 minutes.
#2- how do you remove the intake water screen,part #11 on boats.net ?
#3- On my motor the throttle plate has to be opened a tad to get air & will not start otherwise,but in the neutral position the arm on the shifter rod that stops the throttle plate from moving forward is riding tight on the throttle plate & will not let the throttle plate open far enough to get air so it will start so how do i adjust it?
Thanks

Hi,
Sorry you're having trouble.
Have you tried running the engine with the bypass hose disconnected? If the blockage is inside the block then it should come out with the water pressure from the pump. If you have water coming from the bypass fitting and bypass hose then the blockage is in the intake manifold. Possibly right at the passage for the tell tale exit.

The water inlet screen is accessed for removal when the gearcase is off. It is supposed to be pushed out from the inside. Sometimes corrosion makes getting it out difficult.

Try doing a throttle cable adjustment to see if you can get the engine to rev in neutral.

Shifter in neutral, throttle at START position.

Use the lock nuts to adjust the cable so the throttle arm contacts the shift arm.

Tighten the lock nuts.

Close the throttle grip and use the carb throttle stop screw to adjust for a closed throttle.

If all is good, you should be able rev the engine in neutral to near but not full throttle.

The engine speed should be noticeably reduced in reverse gear.

And, of course, full throttle should be about 5,500 rpm.

If you can't achieve these results then it's likely something is bent or installed improperly.

Let us know what you find and

Good luck.

Good afternoon & thank you for the valuable info ! I found the blockage from the impeller to be in the inlet manifold , like you suggested, in the water channel right before the small discharge tube. so i took it apart cleaned it out real good & then i changed the plugs,changed the oil & fuel filter, She now purrs like a kitten & pees like a race horze! The only problem now is that the throttle plate binds up & the cable won't push it back to the idle position. The throttle plate didn't have a collar so i put one in but i didn't replace the bushings because they appeared to be ok & i only have the bolt that goes through it snug but have tried tightening it a tab more but it still tilts a bit. The cable stop is adjusted properly but the **** arm is still riding riding tight against the throttle plate when in neutral. What would i need to do to the neutral switch to start it in gear ? I know it's for safety but with the boat tied up when started i don't see now it could matter. Thanks again for taking the time to help out,you & honda dude are a huge help !

Well, I hope your definition of throttle "plate" and mine are the same so we can be on the same page here.
I don't want to insult you but I don't know what you know.
The throttle plate is the air valve at the intake manifold end of the carburetor. The choke plate is the air valve at the inlet end of the carburetor. Do we agree?

The throttle cable doesn't close the throttle plate. The cable opens it and/or holds the throttle open. The throttle is closed by a spring that is wrapped over the throttle plate shaft.

The throttle plate return spring must have sufficient tension to rotate the throttle shaft closed while overcoming the "drag" resistance of the released throttle cable.

If the spring is weak from metal fatigue or from being broken or improperly installed or if the throttle cable isn't moving freely the throttle plate won't fully close.

The throttle return spring is not sold separately by Honda but substitutes are available through various hardware sources.

I think I have already mentioned that, if the throttle cable is adjusted correctly then the early contacting of the shift plate is likely being caused by a bent or improperly installed component.

Unplugging the two wires from the neutral safety and connecting them to one another will allow you to start in gear. But, I don't recommend doing that, tied to the dock or not. The sudden movement of the boat could put you or crew unexpectedly overboard and THAT can be disastrous.

Hello,good morning to you & thanks for the well wishes & the info. Sorry that i haven't replied back but my son has been visiting me from the states so i have the throttle issue on hold until later this week, The motor will start in neutral if i spray starter fluid into the air intake & after it warms up it starts on the 1st pull & runs fine, We are talking about the same parts & i do believe that the problem of the shifter arm riding on the throttle plate in neutral has to do with the spring being worn bushings causing slop & not allowing the throttle plate to return to idle, also,the shift arm could be sprung so i am going to replace these parts listed in the boats.net in the handlebar diagram as #s 3,8,7 & 5 in the shift shaft section as #s 31,8,7 & 5. Hopefully this will resolve the problem. Thanks again for your help & i'll post the results when i get the parts !

Hi mickodapp
I hope you're having a wonderful visit with your son!

After reviewing the parts you listed, I think that you may have come up with a good idea about replacing those handlebar components. I question though why you're not replacing the return spring (item 4). It is still available and at $2.17 U.S. it isn't cost prohibitive. It must definitely be weaker today compared to when new so I would also have that on the list.

I'm not as sure about what effect replacing the parts in the shift shaft section will have on eliminating your throttle issues but, then, I am not the "man on the scene" either. The detent spring (item 5) for instance should only need replacing if it fails to provide enough pressure to hold the gear shift arm sector (item7) firmly in each gear as it is selected. It has nothing to do with returning the throttle to the closed position.

Also, you made no mention as to whether or not you've inspected and evaluated the return spring on the carburetor throttle shaft. Is it still there? Is it broken? If not, does it have sufficient tension to "snap" the throttle closed if the linkage is disconnected?

As far as taking time to be with your family as opposed to answering my post....totally understood and agreed with! There is no hurry in this business and family always comes FIRST!

We will be here when you have time to come back to solving this little problem. In the meantime, enjoy your son's stay TO THE MAX!

Good morning to you & thank you for the well wishes regarding my family & yes,we all had a great visit here in Puerto Vallarta, We were able to start up the motor on our 1985 Mac "Nina" with a shot of starter fluid & we cruised the Bay of Banderas on 3 trips with no issues whatsoever We were even rewarded with seeing several giant Manta rays & 4 Humpbacks with their calves. It was a fantastic time & my 45 year old son Jeff, who had never been on a sailboat before took to the tiller like a fat kid to a candy store ! Too proud !

I forgot to include the spring ( # 4 in the handlebar diagram ) in the list of parts that i posted & i do think that it could be the culprit & will order it.Are you referring to this same spring # 4, when you mentioned the carb throttle spring & if not, would you please send me the part # for it ?

I am replacing the shift arm for two reasons,the motor sometimes slips out of reverse & into neutral & maybe the dogs are worn. I have the shift rod adjusted 4 1/2 turns like the manual says.The 2nd reason is that i now recall seeing one of the inexperienced mechanics i used down here ( Honda outboards are rare in this part of Mexico ) hit the shift arm with a hammer & screwdriver, not hard but might have moved it enough to make it ride tight on the throttle plate.

Also, the shift shaft is missing parts # 31 & 8 so i'm ordering them also.
I might as well go ahead & order the spring click ( part # 5 in the handlebar diagram)'

I am going to pull the boat out & put her in dry storage to bottom paint her & install all these parts & hopefully it will solve the problem, Ill let you know how it goes & thanks again !

Well, it sounds like you all are having a sweet time. I would love to watch my grandson as giant mantas and whales swam nearby! We were just talking about the giant manta ray the other day.

Anyway, as to your outboard. Are BOTH shift lever bushings missing?? Even one missing is going cause an alignment and adjustment problem!

The fact there are missing parts indicates someone has had that "mechanizm" completely disassembled. And, THAT means that everything is probably out of adjustment. Even IF everything got put back exactly as they were before (not likely!) the missing components will still have an adverse effect on the "geometry" of everything and, now that I know this, it's not surprising to me that things are binding up.

You need to replace those bushings and thrust washers and then revisit the adjustments. You may find it won't jump out of reverse after the bushings are back in.

As far as the throttle spring on the CARBURETOR, I tried to explain that in post #4 of this thread. Look on the carb where the linkage attaches to see if the carb has a spring over the throttle shaft. If it has a spring, closely inspect the spring to ensure that it isn't broken. The best way to inspect AND test that spring is to disconnect the linkage and work the lever on the carburetor to make sure it opens smoothly and returns with a snap.

If the spring is broken, there is no replacement part number. It is part of the carburetor assembly and cannot be purchased separately.