1978 Johnson 70HP head scratcher

[racerone]

So does the motor run like new with the new stator ?

 

[billythegrape]

No that's why I started this thread

 

[oldboat1]

The stator appears to have some damage at the coil in the 4 o'clock position. Base appears to be chewed up, possibly with a piece missing. Pics can be deceiving, and don't know if issue would be relevant -- but worth checking.

 

[racerone]

Sorry, replacing parts gets expensive.----Good testing , trouble shooting must be done.

 

[billythegrape]

The stator appears to have some damage at the coil in the 4 o'clock position. Base appears to be chewed up, possibly with a piece missing. Pics can be deceiving, and don't know if issue would be relevant -- but worth checking.

Sorry, here's a better pic
Stator

https://imgur.com/a/1XazfHC

 

[billythegrape]

The stator appears to have some damage at the coil in the 4 o'clock position. Base appears to be chewed up, possibly with a piece missing. Pics can be deceiving, and don't know if issue would be relevant -- but worth checking.

Oh I see what you are seeing. I went out and looked, it's a weird reflection from some of the glue.

 

[oldboat1]

Thanks.

 

[billythegrape]

Sorry, replacing parts gets expensive.----Good testing , trouble shooting must be done.

Ya do you think it's worth getting a dva?

 

[racerone]

Pull the cylinder head and inspect cylinders !----A head gasket is a cheap item , relative to what you will learn.

 

[billythegrape]

Man I've already replaced the head gasket. And inspected the cylinders. And checked the head. And the block. And replaced the exhaust manifold gaskets. And checked them.

 

[racerone]

Outboard motors are just a hardworking beast.----Certain things go wrong with them.----Keep digging and you will find what is wrong soon.

 

[ct1762@gmail.com]

eventually you will be forced to take out your DVA adapter to do the proper ignition tests. will save you a ton of frustration in the long run.

 

[billythegrape]

eventually you will be forced to take out your DVA adapter to do the proper ignition tests. will save you a ton of frustration in the long run.

Ordered one last night, it'll be here Monday. Going to get to the bottom of this, it has become personal.

 

[billythegrape]

Well, the cyl 1 reedbox has a leaking reed. Found it during a cylinder leakdown test. Pics attached, you can see light coming through it despite being a bad pic. Checked all the other reeds as a comparison; they were fine.

Reed leak

https://imgur.com/a/rFSWUlp

 

[billythegrape]

I think I'm going to replace all of the reeds. Any suggestions or just go with stock? My DVA comes in tomorrow so that I can double check everything else. Wouldn't surprise me if there were multiple problems.

 

[Faztbullet]

As stated reeds aint yer problem....that is normal and in spec for a engine that old. You are allowed up to .007 gap as the crankcase pressure is what seals them. The problems you have posted to not correspond with a reed issue

 

[billythegrape]

As stated reeds aint yer problem....that is normal and in spec for a engine that old. You are allowed up to .007 gap as the crankcase pressure is what seals them. The problems you have posted to not correspond with a reed issue

Actually it's 0.010". So what you are telling me is that crankcase pressure, even very high pressure, should be allowed to vent through a carburetor, even when it does it on no other reed box besides the top one? That's hard to believe.

All the other reeds are sealed tightly against their boxes, and a cylinder leakdown test does not show air through the other reed boxes, just the top one. How would one possibly perform a leakdown test if high leakage was normal? If this was the case, then a leakdown test would be completely useless on a two stroke, and I don't think that's the case.

The problems I have posted include running rich and hard to start, which while they can also be related to other issues, happen to be reed issues as well. What's your solution then?

 

[racerone]

Install new reeds , possibly new reed boxes and test run the motor.

 

[RBoyd1971]

As soon as pressure from the back side hits it, it should close of unless something is in there. Check to be sure foam from the bonnet or maybe a bug carcass is in there. . I've worked on outboards for 35 years and can count on a half a hand the number that had reed issues.

 

[RBoyd1971]

Did you check the flywheel magnets to be sure none were loose and just stuck on there. Also wondering about the trigger coils. Maybe do a resistance test on them while wiggling the wires. This ain't that complicated.