Cam Won’t stay in position 1956 Johnson 10 hp QD-17B

[Mike Nazarenko]

Recently purchased a 1956 Johnson 10 hp QD-17B Serial number 1422145.

Started breaking down the engine this afternoon. Everything on the magneto plate looks original and clean, and I am planning to replace everything.

To my surprise when I removed the flywheel and checked the points the cam popped up.  I wanted to check the points for operation but couldn’t because the cam would not stay down being pushed up by the spring. In my previous rebuilds I’ve not experienced this, rebuilt a 1958 Evinrude 10 hp and 1958 Evinrude 5.5 hp.

I tried to put the cam back into position but the spring kept pushing it up.  What holds the cam down in place.

 

Thank you.

 

[frankr]

That is normal on that motor.  The flywheel holds the cam down when installed.  You can adjust the points thru the hole in the flywheel OR fabricate yourself a “tool” to hold the cam down.  A piece of some sort of tubing will work.  I think I made mine from a piece of electrical conduit.

[Mumbles]

I think you can take the spring out to while setting the points. I don’t recall ever trying it but it might work.  As mentioned, a short tube held on by the flywheel nut will hold the cam in place.

Something to watch out for, make sure the high point of the cam is centered between the two rubbing blocks on the points. Failure to do this can damage something as the flywheel is replaced.

[Mike Nazarenko]

I have not removed the retaining washers or spring yet.

Is the diameter of the retaining washers large enough to slip by the key, it appears to be very close.  I tried to pull gently but stopped because it just didn’t slip by the key.

Thank you.

[Mike Nazarenko]

The retaining washers cannot be removed without taking out the key.

Won’t be taking out the key or notching the retaining washer to remove the spring.

I will fabricate something to hold down the cam using the flywheel nut to hold the cam in place, the tube sounds like it would work, pvc tube with a washer perhaps.

I’d like to use the timing tool to set the points though setting the points through the hole in the flywheel would be easier though not as accurate from what I’ve read

 

The spring pushing the cam up is surprisingly strong in my opinion.

Thank you

 

[Mumbles]

You can use the timing tool if you finger tighten the flywheel nut on it to hold it in place. Using the tool along with an ohmmeter sets the timing more accurately than a feeler gauge can. Removing the spark plugs first will help in turning the motor over.

The spring has to have some oomph behind it as it’s holding the carbon seal against the upper crank bearing. You don’t want any crankcase pressure leaking out here or the points will be contaminated with oil in no time.

[crosbyman]

 

http://www.youtube.com/watch?v=ga1Cjymj6ms&feature=youtu.be

Joining AOMCI has priviledges 🙂

[aquasonic]

As Mumbles stated, if you’re lucky enough to own the timing fixture with the flywheel nut finger tightened, problem solved.

frankr wrote:

That is normal on that motor.  The flywheel holds the cam down when installed.  You can adjust the points thru the hole in the flywheel OR fabricate yourself a “tool” to hold the cam down.  A piece of some sort of tubing will work.  I think I made mine from a piece of electrical conduit.

I’m thinking that this involves a flywheel nut inside of the conduit, with the conduit extending beyond the flywheel nut far enough to hold the cam in place. Is that the setup?

Maybe a tool could be made from a fine threaded hex spacer, by boring out some of the threads. I guess it would depend on the OD of the spacer. It would have to fit over the  crankshaft.

Improvise-Adapt-Overcome

[Mike Nazarenko]

The timing tool with flywheel nut will work!

 

[crosbyman]

see video and just use the fw… no cost except 3 feet of 22 ga wire

http://www.youtube.com/watch?v=ga1Cjymj6ms&feature=youtu.be

 

Joining AOMCI has priviledges 🙂

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Mike Nazarenko

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