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Honda 50 over revs

fish1

New member
"Hi I have a pair of Honda 50H

"Hi I have a pair of Honda 50HP outboard engines there about 10 years old now and
because of the Maintenance carried out on them there both in good order.
The two power RIB boat.

I have a problem ha ha thats why were all here i guess.

The engine numbers are
BAZL1016353
BAZL 3000307.

THE PROBLEM I HAVE IS AS FOLLOWS.
one engine runs very well and sounds good the other has a wizzing noise about it .
but the problem is this.
one engine at wot speed goes well over 900 revs acording to the rev gauge
I have changed the gauge and the same problem is there.
I changed the revcounters over for both engines and again one says it is going
well over the wot revs.

Both engines have the same props fitted to them both treated the same.
Any idea what this may be ?
is there a part on the engine that needs replacing.
Or is the engine in need of stripping down and sorting.?
Many thanks For your time.

Robert u.k.
.

uhoh.gif
"
 
"Simple things first - it is p

"Simple things first - it is possible that the prop on the over-reving engine has a spun core, or has been bent. If both props turn in same direction, switch them and see if the problem switches over to the other engine. If it switches, repair or replace the prop."
 
Hi Many thank's for your h

Hi Many thank's for your help.
I have changed the props as i thought that as well.

However there both new now and we still have the same problem. both made by Honda and both the same size and pitch 15%.
I thought that changing them would be the answer as one may have been a little out out of pitch.
but now I have been changing them from time to time with the same results.
 
"Other folks on this forum are

"Other folks on this forum are much more familiar with the Honda 50's than I am, so I hope they jump in. But my next step would be to check the accelerator cable linkages at the engine. I think that engine has an adjustable limiter screw or bolt."
 
Hi Thanks for your help
The l


Hi Thanks for your help
The linkages are all o.k. the engine starts and ticks over slow like the other one.
no problems there.

I was thinking there could be something inside the engine that is on its way out or even broken.
There must be some sort of over reving protection fitted but I don't know where.
some sort of wot stop if you like.
The carbs will only go so far as there settings are fixed with the carb stop screws.
if there altered all sorts of things seem to happen like smoke or just cut out.

Both engine's look to have the same stops set.

Robert
 
"Here are a couple of other th

"Here are a couple of other things to look at...

The tach signal comes from the regulator rectifier. It is located on the lower front of the motor. It could be faulty or getting faulty signals from the charge coils under the flywheel.

One simple thing you can do is switch the regulator rectifiers.

Check all of your grounds real good, since a bad ground can make any guage go nuts.

But do not be surprised if that does not fix the problem.

You said there was a whirring coming from the engine. Use a short piece of hose and hold one end near the engine and one against your ear. I think you will probably find the whirring coming from the flywheel area.

If so, the magnets on the flywheel are starting to delaminate and are hitting against the pickup coils under the flywheel. They may have already damaged the charge coil, which could be affecting the regulator/rectifier and thus the tachometer reading.

If you pull the flywheel (only 4 bolts) and check the magnets...use a magnifier and a good light to look for hairline cracks along the layers. You may need to use a small pocket knife to probe and try to move some of the layers (like a dentist probes on your teeth)

If you are truely overreving, the cdi should sense the overrev and will try to shut down the engine. It will result in more of a jerking action from the motor.

If you know someone with a shop tach that has a pickup that can connect to a spark plug wire, you could compare readings."
 
Hi thanks for your help.
I wi


Hi thanks for your help.
I will look at the items you have said.
It could be a week or so before i can get round to it.
Hopefully i will find the problem.
Respectfully

Robert
 
Well i just could not wait cou

Well i just could not wait could I !!1

I have as you said removed the flywheel there is a what seems a slight wear on the top of the magnets.
Don't know how it there but it is.
The wear is Not all the way through and there seems to be no damage to them.

Again i have removed all the earth leads i can find cleaned them and put them on again making sure they have a clean contact.

I have not been out and tried it yet as its blowing a hoolea up here today.
but will do as soon as i can.
If i still have the same i may have to get the engine sorted by Honda.

Bet that will cost me ha ha .
I admitted to say the engine's are 1998 and have run as a pair at all times and just gone over 300 hours.

By the way i put the hose on the engine and again to my ear WOW sounds like a bucket of spanners in a tin bucket.
Tried the other one as well Glad to say they both sound the same ..
I will post any results when i have them
But many thanks to everyone that has help me .
Respect to all.
Robert
 
"}By the way i put the hos

"}By the way i put the hose on the engine and again to my ear WOW sounds like a bucket of spanners in a tin bucket. "

sounds like you might have a broken connecting rod ? i would not run that motor until you've had Honda take a look at it.
might cause futher damage.}
 
Hi Scott
Many thanks for the


Hi Scott
Many thanks for the info.
I had made the decision to have it seen to just in case.
I have to take up to the dealers on Tuesday.
Hopefully there's not to much wrong. ha ha
Now i have said that better get down the bank and see how much they will lend me .

Thanks anyway

Respect to all.
Robert
 
Hi have you recently changed t

Hi have you recently changed the timing belts ? if yes I will have a look and check it as some times incorrect timing can cause engine to over refs
 
Hi Jason.
Yes I changed the b


Hi Jason.
Yes I changed the belts to both engines about 40 running hours ago.
I will have to look and see if i can get the timing marks .
I changed one and then the other to match the existing or first engine changed.
I will try and look Monday as the boat is going to a Honda dealer Tuesday.
I will search the web for the timing marks.
Many thanks
Respect to all

Robert
 
"Align the #1 timing mark on t

"Align the #1 timing mark on the cam pully with the arrow that is directly forward of the pulley.

The flywheel mark should align with the indentation at the end of the hoisting ring base.

Normally if it is just one notch out of timing, it will run like you have carbuartor problems."
 
"Be sure to let the dealer kno

"Be sure to let the dealer know that you removed the flywheel, so they can properly torque the bolts."
 
Hi Mike.
I will have a look a


Hi Mike.
I will have a look and see.
I never moved anything when I changed them but one notch I would not have noticed I guess.

Many thanks
Respect to you.
Robert
 
Well just had a look and a big

Well just had a look and a big shock for me there both right.
Dunno how i did it.

So I guess its to the Honda guys tomorrow.

I have listed the items i have disturbed and a list of stuff I think is wrong.
If i write it down they can't say I did not tell them.

Many thanks
To all I will let you know what the problem was
I HOPE.

Robert
 
HI Mr Neal.
I will do as i wa


HI Mr Neal.
I will do as i want to know myself.
It goes in today to the Honda dealers they recon they will be looking at it Wed and should know whats what then.
Well I hope so.
Many thanks
Robert
 
Hi all the results so far are

Hi all the results so far are as follows.

Nothing wrong with either engine.
both rev Gauges are knackered.
one is 10 years old the other THE NEW one fitted last year turns out it is also knackered.
They tried to tell me the new one had been fitted wrong and it may have caused it some damage.


OOOO say's i and produce the receipt.
funny thing is now as they supplied and fitted it the fitter don't work there any more.

Still that's cost a bit to find that out and i was not about to give them any more so looking for a new one LATER.
I don't know but I just do not think that will be the cure I feel it in my water. ha ha .
anyway thanks for the help everybody soon as i get one fitted i will update this post.
 
Very unusual to have both tach

Very unusual to have both tachs go out at approximately the same time. Makes me wonder if there's not a more serious problem. Best to wait and see.
 
Hi Mr Neal.
the trouble is i


Hi Mr Neal.
the trouble is i don't know when either broke.
One engine is prefect no probs at all this one it's rev counter will be 11 years old plus now.
the what i am calling the problem engine the rev counter was renewed last year.

Maybe its water got in or something else.
I will have to renew the both but it will have to wait now other stuff to buy.
But i will do it before i use it again.
I was talking the eerr indoors about taking it somewhere else and have it all checked again BUT
again it will have to wait.

Soon as it's sorted i will repost
Thanks for your help
 
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