72, 9.5 johnson

patrickray

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Feb 15, 2008
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256
Hi all, I have been working on a 1972 9.5 johnson model 9R-72M. I have it running good. Starts right up, idles down to a purr. But I have a couple questions. First. After it runs and warms up. It wont start again. Im thinking condencers? Next, after its been running. The water out of the tell tell is very warm. I am running it in a trash can. Will it run cooler in the lake or do I have a thermastate issue? Thanks for the help.

Sorry, had the wrong motor. The evinrude runs great. Its the Johnson im having problems with. (thats what he said) LOL

Thanks
 
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tashasdaddy

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51,019
Re: 72, 9.5 evinrude

Re: 72, 9.5 evinrude

when it won't start have you checked spark? i didn't think 72's had tale tells, just the exhaust relief ports on the upper back on the leg. can you hold your hand on top of the head for a 3 count without burning? those motors, if the coils have not been changed, it is time. if you pull the flywheel, i would do it all at one time, including plug wires, and be done with it for another 40 years.
 

HighTrim

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Jun 21, 2007
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Re: 72, 9.5 evinrude

Re: 72, 9.5 evinrude

The water will get warmer running in a barrel as well. You are recycling spent cooling water over and over, heating it each cycle.
 

ezeke

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Sep 19, 2003
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Re: 72, 9.5 evinrude

Re: 72, 9.5 evinrude

When the propeller turns on the 9.5, it forces water into the screen above the propeller, and helps to keep the water flowing. In a bucket, you don't have that assistance, plus the water keeps getting hotter. Unless the pump and thermostat are functioning very well, it is easy to overheat.

When you shut the engine down, the engine is binding due to that heat and the cooling water quickly drains away.

When I run my 9.5 motors in a bucket, I keep the hose running as fast as I can reasonably, to keep the water cold, and let the engine run in forward gear at a slow idle. It can go all day like that.

The water coming from your exhaust relief should be a constant flow, increasing and decreasing in temperature as the 143 dgree thermostat cuts in and out.
 

patrickray

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Feb 15, 2008
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Re: 72, 9.5 evinrude

Re: 72, 9.5 evinrude

My fault (exhaust relief ports) I have very good flow, I just replaced the whole water pump. I didnt check for spark after it wouldnt start. I will do that as well as checking the head temp. If after checking for spark after warmed up and will not start. Im I looking at coils? I will try new plugs as well.
But when she runs she runs good as long as I dont shut it down. I took some short video of it running and then trying to restart. But I dont see that I can put them on here?
 

tashasdaddy

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Re: 72, 9.5 evinrude

Re: 72, 9.5 evinrude

load it to photobucket or my space, and post a link to it.
 

wbeaton

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Jul 30, 2006
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2,332
Re: 72, 9.5 evinrude

Re: 72, 9.5 evinrude

What's your compression like? Theoretically, that problem is possible if your compression is marginal. However, I'd first look to failing coils or too high of a setting on the low speed jet causing flooding at re-start to be the problem.
 

patrickray

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Re: 72, 9.5 johnson

Well, I think I have it figured out. Compression is at 95 for both cylinders. I cant pull the rope that hard due to back surgery about a year ago. But for 95, I figure thats pretty good. I cant belive I didnt think of this befor. wbeaton pointed me in the right direction. Thanks wbeaton. You see, The wires comming off the kill switch are rotted and I have them disconected. So I have been chokeing the thing to shut it down. Flooding the motor! Today I used a jumper wire to shut it down, and always started right up.
Heres another question. On cold starts, is there a way to prime the carb besides pumping the priming ball? It seems that I can pull and pull with nothing. But as soon as I put a few drops of fuel mix in the carb it fires right up. I have the same problem on my 72 9.5 rude.
Well, here are some photos and video on the 9.5 jonson. Please look at the head gasket and let me know if this is something I should worry about. I dont see it leaking but it looks like it has befor. Thanks for all your help.

http://s300.photobucket.com/albums/nn35/1riordan/?action=view&current=waterhigherrev.flv

I guess you will have to copy and paste this. Let me know if it dont work.

Link works good. thanks....

Thanks again.

Patrick
 

4.0l sahara

Petty Officer 1st Class
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Aug 15, 2007
Messages
298
Re: 72, 9.5 johnson

Thats just some corrosion around the gasket. If it bothers you pull the head clean it up and put it back on. It's pretty easy.
headgasket3.jpg

headgasket2.jpg

headgasket1.jpg
 

patrickray

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Feb 15, 2008
Messages
256
Re: 72, 9.5 johnson

Heres another question. On cold starts, is there a way to prime the carb besides pumping the priming ball? It seems that I can pull and pull with nothing. But as soon as I put a few drops of fuel mix in the carb it fires right up. I have the same problem on my 72 9.5 rude.
 

ezeke

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Sep 19, 2003
Messages
12,532
Re: 72, 9.5 johnson

The way to prime the carburetor is to keep the choke plate closed tight until the engine starts. That way all of the vacuum is directed at pulling gas and not air.

If you think that the fuel pump may be part of the problem, get the tank above the engine and let gravity feed the bowl.

If you have the tank sitting on the ground, you are expecting a lot. Make sure the gasket between the fuel pump and the engine is air tight.

The engine at some point was overheated. That is the reason for the discoloration of the paint. It would be a good idea to replace the head gasket just in case.
 
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