Are my reed valves bad?

[John Bett]

Hello, I have a set of used boyesen reed valves for an evinrude v-4. I have been told to check them for any light passing through to determine if they are ok. When I hold them up to a bright light, a couple of them let just a sliver of light through, like less than the thickness of a playing card. Is this acceptable? Just want to check before installing.<br />Thank you!

 

[R.Johnson]

Re: Are my reed valves bad?

On those fiber reeds, check for any sign of scorching as caused by a lean fire spit back. Don't worry about that slight light leak. Did you get just the reeds, or the whole reed box assembly? If you have just the reeds, install them on what ever side lays the flatest. Don't forget to richen up the low speed jets. What year, and size engine are you dealing with?

 

[John Bett]

Re: Are my reed valves bad?

My motor is a '72 125 Evinrude (Thank you for your response),Well, I must admit that I bought them used on ebay after asking the seller if he could see any light through them, he said NO, (they came on the blocks, but I cant tell if they are Evinrude or boyesen blocks. They look stock), just to find that I COULD see light through them all. Instead of getting angry, I tried to make the best by fliping them to get the flattest result. Also on the ported reed, it has a little rubber strip which I carefully removed and affixed to the opposite side. I dont see any scorching, but there is still a little sliver of ligh on several.

 

[John Bett]

Re: Are my reed valves bad?

PS, I do have the larger jets (3sizes)

 

[Basscat 1]

Re: Are my reed valves bad?

Your putting used reeds on your engine? These reeds are designed to go on one way with the tape side of the primary reed facing down towards the reed block. It also warns int the instructions not to remove the tape.<br />P.S. Try to stick to one thread for one problem. Its less confusing that way.

 

[R.Johnson]

Re: Are my reed valves bad?

Sorry! I forgot about the tape on one side of the reeds. You should be Ok, and the block's whould have to be OMC. There should be no reed stops when using Boyesen reeds. A positive crankcase pulse will take care of that light leak. Who came up with the light leak test? You would have to buy a bushel at a time to find the one's that would pass that test.

 

[Basscat 1]

Re: Are my reed valves bad?

The light test was shown to me by a buddy of mine who has been working on outboards for 20 years now. You can make it work if you hand sand the reed blocks per instructions with the Boyesen reeds. He compared my reeds to a new engine that he tore down for other reasons. The new engine had stock reeds, but there was no light emitting around the edges.<br />Believe it or not, my engine wouldnt idle. After the second tear down, he showed the light trick, and sure enough every reed had light going around the edges. I was loosing so much crank case pressure that my engine didnt want to idle, and would spit back through the carb and eventually die. Top end was fine. After replacing the reeds with the Boyesen reeds and hand sanding the blocks, it idles and runs great.<br />You got to remember something. We are talking about engines that are 20-30 years old. The stainless steel reeds will eventually have wear marks around the edges, but the cast aluminum blocks will definitely have wear due the reeds slapping them thounsands of times per minute.<br />I am just giving out a suggestion here, fix it how you see fit.

 

[R.Johnson]

Re: Are my reed valves bad?

I guess I would have to say, I have been working on OMC engines since about 1962, as that was the first year I went to Evinrude service school in Milwaukee, Wis. Outboard engine repair has never been my first line of work, I was a full time firefighter, so it was always my second job, can I claim 43 years here? Changing reeds is what I would call a band-aid fix. They are seldom the cause of a poor engine running problem unless they are broken, They are a spring steel, with a positive stop, so they are almost impossibble to bend out of shape. The Boyesen reed is a definite improvement because they respond instantly to any positive, or negative impulse simply because they are softer, and lighter. They also flow wide open per engine demand because of the no stop feature. A factory installed reed will respond to a very small impulse, look elsewhere for the problem. If your engine responded to Boyesen reeds, what would unstuck rings, and proper tune-up do? Did you use a set of wire guages to check the jet size when rebuilding the carbs, after 20 years, I did.

 

[Basscat 1]

Re: Are my reed valves bad?

This is my theory on why Boyesen reeds work better on older engines. As older engines begin to wear they start to loose compression, but more importantly they start to loose crankcase pressure which is vital to reed operation. At the same time, blowby caused from the worn rings enter the crankcase.<br />The Boyesen Reeds help compensate the loss due to their dual stage design. The lighter outside reed makes for easier starts and smoother idle since it responds, as you said, to any positive or negative change.<br />As far as my engine goes. I completely tore down the engine. One of the cylinders has a small amount of wear, but it was still with in tolerance and was not bad enough to send off the engine block. While I had it apart, I thoroughly cleaned the pistons and rings with brake cleaner, and carb cleaner. There is no carbon build up. I am certain the rings are not stuck, but there may be a min. amount of blowby. I did a compression test,( 120 each cylinder) but I did not do a leakdown test. Like I said, I am postive an engine this old has some blowby, but I am not worried about that.<br />I replaced all the ignition parts with the exception of the flywheel. I put two new carbs on I purchased from a buddy of mine. Now the jets. I used a machinist drill twist, which is used for cleaning torch tips. I used a digital micrometer and re-jet the carbs up 3 sizes.<br />A Fireman is a very respectable job. Congratulations.