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Chrysler 1975 757HA 75 HP Gasket question

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Rzbker1974

New member
Ahoy Matey's,
I am attempting to restore the old motor that has been sitting for 4 1/2 years. Been having problems with water not getting to the thermostat. I will post another thread on that progress (dropped lower end and checked impeller, all good, flywheel shear key good).
My immediate problem:
In checking the thermostat, I had to remove the cylinder head cover to access it. The cylinder head came off with it (no problem). Head gasket in good shape.
Good news is that the thermostat tested good.
Bad news is that in the parts diagram listed on this site, there is no gasket shown between the head cover (#68) and the cylinder head (#72). Guess what, there is one and needless to say, needs to be replaced.
How am I supposed to find a replacement if the diagrams don't even show one?

Thanks in advance for any replies.

S
 
The only problem I see with that is it has metal around the spark plugs intergrated in the old gasket.
Your right though, I'll give it a go.
 
Tach and stuff 001.jpgTach and stuff 002.jpg
Use silicone. Verry thin.

Water to the thermostat???
The bucket needs to be real deep(4" over the cavitation plate) for water to be picked up.
The impeller isn't self priming.
Also if muffs are used?? you might need special muffs, see pics, depending on the water pickup???
 
thanks jj05
I did have the cavitation plate completely submerged in a large trash can by a couple of inches (maybe not deep enough). It never circulated.
I am planning to drop the lower end again and blow air in the water inlet tube to the power head up and out and see if anything gets up to the thermostat. Water jackets were bone dry around the cylinders after I opened it up.
 
Update:
I got a sheet of gasket material and crafted a new one. Seems to work fine.
Also made new carb intake gaskets. Put it all back together and tested in trash can. The starter started dragging to the point it would not turn over or disengage (pull down from flywheel).
Pulled starter and cleaned the brushes and blew it out. Had some rust in the bottom by the brush clips. Replaced and it cranked like a dream for a few tries, then started dragging again.
The kicker is this time the solenoid got hot on the positive side and started smoking.
Can't find a short or enlarged wires.
The question now is, do you think it's the starter or the solenoid?

I see a new 60 hp, 4 stroke Tohatsu in my future...........
 
Buy Mercury or Yamaha.
Better warranties from what I understand???

You do a compression test?
Remove the plugs and see if the starter works then??
Try to turn it over when you drop the lower unit? could have siezed bearings
in the lower unit and causing it to drag?
 
cranks fine without plugs.
Have not dropped lower unit and cranked.

Guess that's the next step. Also have not run compression test yet. Will update.
 
Maybe a Chrysler SM can help too...….

[FONT=Verdana,Arial,Tahoma,Calibri,Geneva,sans-serif]https://www.manualslib.com/manual/1000030/Chrysler-75-H-P.html[/FONT]
 
757HA Chrysler, You may want to check the grommet under the power head. Item #40 in the parts catalog under lower unit. There is a test you can do. There is a special tool for the drive shaft spine. You can weld a rod onto the end it and use an electric drill and turn the drive shaft clock wise and see if the pump is working.Make sure you use a bucket and not the muffs. This would done before you try and pull the power head. If the pump works with drill the problem is either the water tube and or grommet or power head which I don't believe it is.
 
Thanks bucko and dave69 for the responses. To be quite truthful, I am going to a dealer and try to find a good new "used" 60 hp motor. I was gifted the 1974 Ranger 16' boat and trailer. I've completely gone through this motor and I am going to need something more reliable to put-put around Beaver Lake even if I can finally get this thing going.
 
1/2" drill on the end of the shaft instead of welding a piece to the end of the drive shaft.
This lower needs the muffs I posted pics of or put in a bucket 3-4 inches over the cavitation plate.
Once you get the buggs out, you'll be surprised how dependable they can be.
Remember buy American made outboards.
 
Rzbker1974 said:
The only problem I see with that is it has metal around the spark plugs intergrated in the old gasket.
Your right though, I'll give it a go.
Click to expand...

The reason why Chrysler never made a gasket for this cover is that it will interfere with the heat transfer to the overheat sensor with the gasket between the 2 faces .
 
Rzbker1974 said:
thanks jj05
I did have the cavitation plate completely submerged in a large trash can by a couple of inches (maybe not deep enough). It never circulated.
I am planning to drop the lower end again and blow air in the water inlet tube to the power head up and out and see if anything gets up to the thermostat. Water jackets were bone dry around the cylinders after I opened it up.
Click to expand...

You can put a new pump and impeller .If the exhaust port cover water ways are blocked the piston sleeve will not get water it will be bone dry ,the only way water gets to the piston sleeves area is through the exhaust cover these covers get blocked especially if it has been used in salt water and over the years the salt eats holes in them or they start showing sings of cracking and your poppet valve will be salted up and problem getting it out but Durbans formula gets it out and cleans up the salt too . you will notice it on the left hand side looking from the port side. i have some photos to show you later
 
Well folks, after much effort, the old chrysler is destined for the junk heap.
After checking with dealers, I have come to the conclusion that if you are looking for a used outboard it is either:
1. wore plum out
2. blowed up
So instead of putting a new ($5,500) motor on a reconditioned 1974 boat, I found a blowed up, 2004 70 hp Evinrude that my dealer is rebuilding with a new power head, tilt/trim and controls, installed for $2,500.
757HA may have been it back then, but it is a POS.

thanks for all the replies and keep em' wet boys!
 
Look around.
Found a running 125 Force for 125$
Just needed a flywheel key.

If you change brands? you'll have to change the shifter and controls.
Chrysler and Force used tthe same controls.
 
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