Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnson115

rothfm

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I had another post asking about what the reed plates actually did. But Yet another question now.

When I lightly tap the reed "fingers" against thier backing plates on my workbench...3 of the assemblys sound solid against thier backing. One Reed Assm has several fingers that make a hollow sound when I tap them. Like they are not sitting down solid against thier backing like the others????

Is this a problem? (bet it is). From the parts breakdown, it doesnt look like the read portion is replaceable. Can it be taken apart and flexed a bit? Or find a better used/new one(if avail new)

Deep into my 1st Motor rebuild, and not really familiar with reeds.

Its a 1984 Johnson 115
 

Capt Ken

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

Hold them up to the light and see how much light shines through between the plates and housing. I have unscrewed plates before and flipped them over to tighten them up. One one better, just replace them all
 

emdsapmgr

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

Usually that is not a problem. When the piston is in the downward travel stroke, the crankcase compression causes the reeds to close and lie flat against the reed box. What fuel/oil mixture is around the reed will cause it to seal properly. The reeds don't have a "side", so you can flip them like Ken said. As long as you have it this far apart-ever consider going to composite reeds?
 

Faztbullet

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

I have unscrewed plates before and flipped them over to tighten them up.
The reeds don't have a "side", so you can flip them like Ken said.
Oh come on guys, service school and the manual plainly states DO NOT FLIP USED REEDS!!! These are spring steel and after use the pedals take a set as the steel in flexed in that direction, reversing them flexes metal in opposite direction causing breakage. Just order you a set of Chris Carson reeds and carry on with the rebuild.

View attachment IMG.pdf
 

HighTrim

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

While I am by no means an OMC mechanic, I have a friend who is. It seems like the school, (along with the manual) brainwash them into thinking that no parts are reusable. They push change, change, change. Wonder if it has to do with the money they make on the parts?? He was amazed when he was over and saw me dressing old points sets. They simply toss them in the garbage in their training and put new in.

I myself have never encountered faulty reeds, but if I was doing a full rebuild I would likely just order aftermarket as stated above and be done with it. If I was up north on the water and needed it fixed would I flip them? Of course I would, just dont tell the teachers at school ;) I think all the guys above can agree on that, it can be done, but why when you have it all apart and have the opportunity to do it right the first time.

Just my 2 cents.
 

Faztbullet

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

He was amazed when he was over and saw me dressing old points sets. They simply toss them in the garbage in their training and put new in.
The reason behind this is the platinum coating is thinner on the newer points and if dressed with a abrasive it will thin /remove coating allow points to burn/build up. Service school teachs you to clean with 2000 grit crocus cloth and cleanup with pure alcohol, and if dull replace as platinum is beyond usefulness.
I think all the guys above can agree on that, it can be done, but why when you have it all apart and have the opportunity to do it right the first time.
I will disagree with that as I am not going to risk my or customers money/time on a item that damage the motor sooner or later. I will install a new/used/aftermarket part before I try to save a few bucks on a oncoming failure, heck that like telling someone you can flip a impeller over and reuse it, it might work for a while but you can be danged sure that it going to fail .....
 

boobie

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

I'll have to go along with everything Faztbullet said !! Unless the instructors in the service schools I've been to in the last 40 yrs or so were totally wrong.
 

HighTrim

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

Sorry I think my statement was taken out of context here. I totally agree, as stated, that the reeds should be changed in this case. Just stated that flipped reeds will in fact work, and in an emergency like up north in the bush I would flip them if I had to, that is all. Was by no means trying to start a debate on it sorry.

Alot of the skilled trades are turning into installers rather than trademan I fear, not just mechanics. There are thousands of extremely knowledgeable and skilled mechanics out there, dozens on this great site alone.
 

rothfm

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

Thanks all....havent heard of Composite reeds. Will do some research on where to get. Agreed, Its all apart on the bench and now is the time to do it right. The measurements and subsequent hone job came out great.

Composits here I come....Are they better than the metal ones I got? I dont think I can even get those new anymore right?

Thanks again,

mark
 

boobie

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

HighTrim think about this. If you take a piece of metal and bend it only one way it's hard to break. But bend it both ways and it breaks easely. Same thing about reverseing reeds.
 

emdsapmgr

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

Mark, check out Boyesen reeds on the web. If a composite reed ever breaks, it won't damage the powerhead.
 

rothfm

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Re: Reed plates dont sound the same when tapped with finger on workbench? 1984 Johnso

Getting back to my Reed question...finally done some more research. While I'm staying all original with this rebuild, I'm going to opt for the Boyesen reeds. I dont mind the reduced longevity. I know about lean sneeze at startup affecting them too. But the peace of mind knowing if one breaks, my work isnt destroyed--made my decision. Now to save up some further dollars to get them. Pistons first.

Thanks for all the input.
 
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