evinrude 40 hp 1964 impeller question

[chestercheese]

hello people, i have an old evinrude big twin/twin spark, (dont know which one it is?) i've changed the coils and points, it starts and runs great now, just a quick question on the pumping water side? i'm not sure how great it should pump the water out, it does wet my hand when i put it over the exit and has a lot of condensation coming out, i've looked on youtube and all of them on there show not a lot of water coming out, is this how it should be????? many thanks any help would be great, cheers dan

 

[kbait]

Re: evinrude 40 hp 1964 impeller question

If it's misting at slowest possible idle, it's likely fine. You should be able to touch the head near spark plug for a couple seconds after running slow for several minutes. If water will boil off the head, it's way too hot, so check as you go...

 

[chestercheese]

Re: evinrude 40 hp 1964 impeller question

hello and thanks for that info, i will try this weekend and see how hot it gets, i've not had it running for long cos i was'nt sure about the impeller? i will run it for 10-20min and see if i can touch the head with out burning myself, sorry but just another Q:redface:, is there anything else i should check, cos its not been running for a few years, i've done all the electrical side, but nothing mechanical, i,e is there any oils etc i should change?? many many thanks for your help

 

[lindy46]

Re: evinrude 40 hp 1964 impeller question

If it's not pumping water well, 10-20 minutes is too long to "warm it up". Start checking temp of head after about 30 seconds. I would plan on changing the impeller if it hasn't been run in several years. Also drain and refill the lower unit with gear oil. Look for water in the oil, or if it's milky, you have a bad seal somewhere.

 

[F_R]

Re: evinrude 40 hp 1964 impeller question

If it's not pumping water well, 10-20 minutes is too long to "warm it up". Start checking temp of head after about 30 seconds. I would plan on changing the impeller if it hasn't been run in several years. Also drain and refill the lower unit with gear oil. Look for water in the oil, or if it's milky, you have a bad seal somewhere.

No matter whether or not the impeller is bad, you need to understand the system on that motor. It has a thermostat controlled recirculating cooling system. When you start the motor and it is at less than operating temperature, the thermostat will be closed. When closed, a bit of water is discharged as a tell-tale and to cool the exhaust pipe. But most of the water is directed back down to the water pump and recirculated. That goes on till the water is warm enough to open the thermostat. When it is open, a lot more water is discharged and the recirculation stops, instead fresh cool lake water is introduced to the system.

It is important to realize that the thermostat is constantly sampling the water temperature and is constantly opening or closing as necessary to maintain ideal operating temperature. For that reason, the amount of water you see being discharged out the back is constantly changing from just a bit to considerable and back again. At idle speeds, and cold lake water, the 'stat might not open at all because enough cold water is being introduced to keep it below thermostat opening temperature.

What does this all mean?? It means that you can't be going around all day dribbling water on the head to see if it is working. Nor are you going to be going all day with your head cranked around backwards to see if water is coming out. There are nicer things on the water to look at. Bottom line: Make SURE you have a good water pump in there and then don't be worrying about it. By "good", I mean a new or recently new impeller and the rest of the pump isn't worn out.

But you say you have a temperature warning light? Hah!! They come on after it is already overheated and the damage is probably done. They don't call them "idiot lights" for nothing.

BTW, your car works exactly the same way except a radiator replaces the lake, and no water is squirted out to look at. You trust it, don't you? You make sure the system is in good working order and drive.

 

[chestercheese]

Re: evinrude 40 hp 1964 impeller question

hello thanks for that great info, the impeller was ment to have been changed before it was given to me, i've done the coils and stripped the carb and clean'd, does start up first time, changed the gear oil, does it only go into gear when the engine is running????? any of idea what the water pump and impeller is like to change? where can i get one from? are they one part or seperate? and where about is it on this type of engine, sorry bout all the Q's, its just i've had such bad luck with outboards

 

[F_R]

Re: evinrude 40 hp 1964 impeller question

hello thanks for that great info, the impeller was ment to have been changed before it was given to me, i've done the coils and stripped the carb and clean'd, does start up first time, changed the gear oil, does it only go into gear when the engine is running????? any of idea what the water pump and impeller is like to change? where can i get one from? are they one part or seperate? and where about is it on this type of engine, sorry bout all the Q's, its just i've had such bad luck with outboards

So, you have a Big Twin (manual shift) and not a Lark(electric shift) right? Starting at teh bottom of the motor and moving up, you will find a flat anti-cavitation plate and above that, a bulge. Teh watr pump is in that bulge. The "impeller" is part of the "water Pump". They have the impellers here at iboats, but not the rest of the pump, if you need the rest.

To get at the pump:

If there are split covers over that bulge, remove them.
Remove the lower rear cover (rear cover of the mid-section)
Remove the diamond shaped plate from the side of the mid-section
Behind that plate you will find another one. Remove that one too
Behind that second plate you will find the shift rod connector. Remove the lower screw
Now remove the six smaller bolts and one large bolt holding the lower unit on.
Twist the lower unit back and forth gently while pulling it down. It should come down and away.
You will now find the water pump looking at you.

 

[chestercheese]

Re: evinrude 40 hp 1964 impeller question

thats great, makes me want to go out and do it now, but it's 9o'clock and bloody freezing out, i will have a go at the weekend and let u know how it all goes? i will run it first and see how it pumps water, so does it need to be running for it to go into gear? and yes it is a big twin manual shift, are these engines reliable?????????? thanks again for your help, much much appreciated

 

[F_R]

Re: evinrude 40 hp 1964 impeller question

thats great, makes me want to go out and do it now, but it's 9o'clock and bloody freezing out, i will have a go at the weekend and let u know how it all goes? i will run it first and see how it pumps water, so does it need to be running for it to go into gear? and yes it is a big twin manual shift, are these engines reliable?????????? thanks again for your help, much much appreciated

1. No it doesn't have to be running. However, you may have to twirl the prop a bit to align the gears so it can shift. And the throttle has to be at a "slow" setting

2. Reliable??????? If in good condition, VERY!!!! If misused and abused, junk is junk.

 

[chestercheese]

Re: evinrude 40 hp 1964 impeller question

hello again, i can now put it in gear, its abit stiff but does go in and out ok, anything i need to do to make this easyer or will it get better when running and worked a few times? i cant wait till tomorrow so i can get out there and have a play with it, many thanks for all of your help,

 

[chestercheese]

Re: evinrude 40 hp 1964 impeller question

hello,
i went and got the outboard going today, started after just 3pulls, but then the carb was throwing loads of fuel out the air in take, can you think of what i've done wrong when i stripped the carb? any help would be great,

 

[bktheking]

Re: evinrude 40 hp 1964 impeller question

Did you mess around with the float adjustment?

 

[chestercheese]

Re: evinrude 40 hp 1964 impeller question

yes, i had stripped it all down, as it was all very dirty in there, but i cant think of what i've done that would cause the fuel to come out like that?

 

[bktheking]

Re: evinrude 40 hp 1964 impeller question

yes, i had stripped it all down, as it was all very dirty in there, but i cant think of what i've done that would cause the fuel to come out like that?

What condition was the float in, it should also be parallel with the carb body when the carb is upside down? If the float doesn't rise and close the needle on the seat the fuel flow won't stop when it should and it will puke gas. I can't see it being a reed problem as it didn't do it before you played with the carb. The float may also be rubbing up against the carb bowl not allowing it to rise, pull it apart and inspect.

 

[Willyclay]

Re: evinrude 40 hp 1964 impeller question

If you would like a free, scanned copy of a non-factory service manual that covers your motor, send me a Private Message with your email address and I will reply with the manual attached. FYI, it is not as complete as a factory manual and the pictures are fuzzy but it served me well for many years with an earlier model of your motor. Good luck!