1950's Evinrude Fleetwin 7.5 HP Spark Plugs Leak Oil

nwcove

Admiral
Joined
May 16, 2011
Messages
6,293
no kill switch on that one, and no difference in spark for any where you twist the tiller grip, if it jumps a 1/4" open air gap with a good snap yer good . is the carb roller hitting the cam on or near the mark? is the mag plate wobbly?
 

andy7918

Seaman Apprentice
Joined
May 20, 2014
Messages
38
It's close, within a .25". This model has an arm not a roller, but the arm contacts the cam .25" past where it should. I tried pulling up on that arm at wide open while I was on the lake and it didn't seem to make any difference. I will definitely check that adjustment in my manual though. What do you mean by mag plate? By full throttle affecting the plug wires: I meant as the coils, plug wires etc rotate counterclockwise as the throttle is increased. I reused the original wires as they checked with a multimeter. They were a tight fit as they were a little short, so perhaps they are binding up and pulling off the coil stud a little, maybe enough to cause the miss?
 

andy7918

Seaman Apprentice
Joined
May 20, 2014
Messages
38
So I adjusted the cam on the timing plate as far as it would go, I also invested $12.00 into new solid core wires, plug boots etc. Pulled the flywheel and replaced the wires & regapped my points. Took the boat out Saturday and it rips. The motor runs great at wide open throttle, so I am pretty sure the plug wires were the issue. The high speed needle wont hold adjustment as somewhere along the way the shaft got bent, I will have to pick up a "new" used one on e-bay. Also how do I know if the impeller is working right? The motor "sprays" water out of the front, not a steady "****" stream like more modern models. I was cautious and kept feeling the temperature of the water with my hand, it got pretty hot at wide open but cools right down on trolling speed. The cylinder head was hot too, but never so hot I couldn't put my hand on it. I figure if any water at all is coming out the impeller should be functioning more or less correctly? How difficult of a job is that to replace? Thanks for the help NWcove and T Frank, it's great to be able to get ideas from other ppl when trying to figure something like this out.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,047
The powerhead has to be removed in order to change the impeller.---If you do not know the condition / age of the impeller it needs a new one.---Sudden failure of old impellers happens all the time.--Then it is time to look for another motor !!
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,047
The powerhead has to be removed in order to change the impeller.---If you do not know the condition / age of the impeller it needs a new one.---Sudden failure of old impellers happens all the time.--Then it is time to look for another motor !!
 

andy7918

Seaman Apprentice
Joined
May 20, 2014
Messages
38
Are there any other parts I should be replacing while I am in there? Seals gaskets etc..?
 

AlTn

Commander
Joined
Mar 9, 2010
Messages
2,813
this might yield some insight...youtube....Dropping the Lower Unit on Mid 50's 5.5 and 7.5 Johnsons and Evinrudes
 

andy7918

Seaman Apprentice
Joined
May 20, 2014
Messages
38
http://s113.photobucket.com/user/ANDY7918/library/fleetwin2 I added some pictures of the impeller & housing. It doesn't appear that anything is wrong with the impeller what do you think? Is it the wrong size? I went ahead and ordered a new one from NAPA 18-3001, hopefully it fits. One weird thing is there was what appeared to be an unused welch plug sitting loose in the lower unit at the rear of the impeller housing. it is shown removed and in place in two of the pictures. It was covering a drain hole on the back of the housing. Is this supposed to be here? I plan on leaving it in there when I put it all back together... Also I have a new powerhead/lower unit gasket that came with my gasket kit. It is a hell of a lot less thick than the old gasket, Is there some sort of endplay requirement on the driveshaft that would necessitate a thicker gasket?
 

nwcove

Admiral
Joined
May 16, 2011
Messages
6,293
that old impeller is toast. not sure how that " plug" ended up where it is, but it has no reason to be there. the base gasket should be roughly as thick as three three business cards stacked together....or at least thats how thick the oe gaskets i have are.
 

andy7918

Seaman Apprentice
Joined
May 20, 2014
Messages
38
So I replaced that old impeller, put it all back together and ran it in the test tank. No water at all.... Took it apart checked my work, and I am pretty sure I didn't get the pickup tube in on the impeller. So put it all back together again right this time and It sprays a ton of water. (gotta love doing a job twice...) I felt the head while the motor was idling in the test tank and it is really hot. With the old impeller it was usually just a little warm on idle, but it is really hot now. I am wondering if I screwed up when replacing the powerhead/lower unit gasket. I didn't use any rtv, just emery cloth, scraper, & brakecleen on the gasket mating surfaces, could poor gasket installation be causing the motor not to cool right?
 

andy7918

Seaman Apprentice
Joined
May 20, 2014
Messages
38
So the motor runs good, but i am having problems with the pressure tank fuel fittings leaking where they connect to the motor. I replaced o rings, but it still leaks, and when i remove the female connector from the male connector on the motor all of the fuel dribbles out of the mail connector. I dont have a schematic of what the inside of these fittings look like. Is there some sort of one way valve in the male one? Could i just replace both of them with an in-line quick connect of some sort and not have to deal with the leaky ones i have? Do the stock fittings requlate pressure or fuel flow in some way?
 

andy7918

Seaman Apprentice
Joined
May 20, 2014
Messages
38
So I went to take the motor out last weekend, and it doesn't run right. It starts right up in neutral, but will only start with the choke on, even after its been warmed up. I stated wide open across the lake and it slowly ran out of juice and died. It will start and run in neutral but as soon as I put it into gear and start cruising the motor slowly loses rpms and dies. Sounds like a fuel issue right? I haven't taken the carburetor apart yet, but I was wondering if the answer is obvious to one of you all based on the symptoms I have described.
 
Top