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1972 Johnson 4hp running hot

More progress:

Was able to remove the pc of snapped drill bit. I tried to use a diamond dremel bit to make a hole in the bit, but wasn't able. But it loosened the bit enough for me to wiggle it out with two straightened dental picks. Drilled and tapped - all good !

When I added water pressure via hose to the brass water pick up ( by-passing impeller ) water was flowing perfectly, but there was a TINY droplet of water forming on the edge of the exhaust cover in the area near my new tap. I think it goes back to the corroded exhaust cover ( don't think they make that anymore ) - so I'm going to have one fabricated. I don't think that a garden hose pressure at less than 25% should allow that to happen - right ?

Anyway that's where I'm at - on my way to a 'happy ending' ;)
 
Wow - good idea - it's different from mine and won't fit but thank you for looking !

I'll keep an eye on eBay - I wonder who else might have this ?
 
Installed exhaust cover and the same area, near where the bolt/drill bit had originally snapped is leaking. I had re-tapped, put on a clean exhaust cover and now this cover still has a drip-drip leak there. When I tighten the bolt more it leaks even more. Now it's leaking a little worse after tightening that one bolt and I'm going to pull off the exhaust cover again inspect. What do you guys think ? Is there way to make my own gasket that would be 'meatier' than the stock one to fill in any tiny gap or irregularity ? Also, is there a proper torque for these exhaust nuts ?

As an aside, ran the motor for 20 minutes - ran as cool as a cucumber ! This bolt has been giving me the worst of the problems !
 
Thx. for torque spec.

With regard to the Perfect Seal - is it to be used with a gasket or as a replacement for a gasket?

If as a gasket alone, is it best to make the gasket, mount exhaust plate but NOT tighten all 'home' until it cures and then torque it the next day ?
Or, form a gasket, torque it all down then and there and let sit overnight before running ?

Never used the stuff.

Please advise.
 
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I don't think that exhaust cover is held on with 1/4 -20 bolts.-----Perhaps they are 10-24 and the tork would be lower than what is posted.
 
I like the idea of trying to smooth the block. I could use the old exhaust cover as a 'block'.

Is using Indian Head gasket adhesive with an OEM gasket a no-no here ? I've always liked that stuff !

Perfect Seal - used with the OEM gasket, or as the gasket itself ?

Almost there !
 
I think this might be the last post. I'm good !

First - thank you for all the help and input. This site is truly a great resource ! Put it all together last night and the exhaust cover did not leak.

A few things that I learned and or liked.

- after taking the lower unit off, I tried to run fresh water through the brass tube that normally connects to the water pump - and the water would not flow through at all - the hose would actually, from pressure - pop off. This made me realize that there was a clog somewhere. I straightened a wire hanger and ran it up the brass tube and luckily my obstruction was there.

- removing the head and or the exhaust cover to inspect the innards must be done carefully. DO EVERYTHING TO NOT SNAP A BOLT in the process ! It can really ruin your day. If you do snap a bolt, try for an accessible one :)

- If you snap a bolt or a drill bit trying to remove either, BREATHE and think. I was able to take two short pcs of paperclip, straighten them - squeeze them in a vise grip - very close together, to make a sort of mini tweezer. Then, I fished this in the space between the snapped drill bit and the bolt hole - then I twisted the paper clips grasped/locked onto the drill bit and I was able to extract it out. Miracle !

- Use a dremel with either a diamond bit or, I found the tungsten bit to be great - to loosen things up. The vibration allowed the remaining bolt to be cut through allowing a good hole to re-tap. The dremel gives more control than a drill bit.

- Great advice was to use a VERY flat pc of metal or glass, glue sand paper to it and lightly fair the engine block till all shiny. This, I believe was the final solution to allowing a perfect seal between the exhaust cover and the engine block. BTW - In the end, I did not use the PERFECT SEAL product, I used OEM gasket and OEM adhesive and it it working fine. But, I like the Perfect Seal idea -

Lastly, I do not own a torque wrench, but I believe not over tightening is critical here. Just right is key.

Thank you again. Hopefully, my little 4HP '72 Evinrude ( I initially thought a Johnson ) will provide me service a for a few more years.

One thing I don't understand is - what the heck could have gotten stuck in the intake tube ?!?!? It has a fine intake screen on the lower unit - can't imagine.
 
Thx again. I ran her for 15 minutes, fogged her, changed oil. Stored. I thought the engine was cooked several times during this repair. I lucked out !

Until the next time.
 
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