Help with Evinrude 1974 4HP

ceno

Cadet
Joined
Mar 12, 2009
Messages
7
Hi, would appreciate some help. Cannot get Evinrude 1974 4HP (Mod No 44B36R) to run. Have a similar 1979 motor and have proved carb and magneto by exchanging on other motor. I have good equal compression on both cylinders (105psi), I have a good spark and sometimes get an occasional fire. Plugs do not appear to get very wet. I have removed reed valves and they appear to be fine. I get the feel there is not alot of crankcase vacuum, not much 'sucking' noise from the reed valves. Don't think the top crankshaft seal has gone as its very clean under magneto, there does not appear to be a bottom seal according to the manuals I have? Don't know how to check for crankcase vacuum without opening and checking seal. Has anyone got any ideas.
Thanks
Ceno
 

tashasdaddy

Honorary Moderator Emeritus
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Nov 11, 2005
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51,019
Re: Help with Evinrude 1974 4HP

will it start if you spray premixed fuel into the carbs? is the choke closing?
 

ceno

Cadet
Joined
Mar 12, 2009
Messages
7
Re: Help with Evinrude 1974 4HP

Thanks for getting back,
I've tried squirting premix with a syringe in through carb and through plugs and only get the odd fire. I maybe flooding it though, how is best way to get a spray. Carb (and choke) is working fine on other outboard.
Ceno
 

Don Hansen

Petty Officer 1st Class
Joined
Sep 17, 2007
Messages
230
Re: Help with Evinrude 1974 4HP

I thought the same thing about the crankcase vacuum when I had trouble with my 1970 4 hp a couple of years ago but that appears to be normal. In my case it was the carb which I took apart probably 4 times and finally installed an overhaul kit before it ran right.

Here's something you might look at. I've had my 4 hp since 1974 and from experience one of the first things I look at when the motor acts up is the bottom spark plug wire. The motor cover had a habit of hitting that wire when you remove/install it. I've found that the boot can be pulled loose from the wire after awhile. I now wire tie the boot to the wire.

Don H
 

JB

Honorary Moderator Emeritus
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Mar 25, 2001
Messages
45,907
Re: Help with Evinrude 1974 4HP

Except for the carb and a few bits in the magnetos those two cylinders are independent 2 stroke engines. Whatever is preventing it from starting is something they share.
 

Rick.

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Jul 30, 2006
Messages
3,740
Re: Help with Evinrude 1974 4HP

Just use one of those trigger spray bottles with pre-mix in it. I would hold off on putting it in the cylinders as that could more easily wet your plugs so much they won't fire. It could be that you still have to adjust the low speed needle a bit when you switch the carb. to the 74 motor. Try turning it out in 1/4 turns all the way from 1 turn from home till you get to even 2 1/2 turns from home. That will richen things significantly provided your carb. is functioning well. These are great motors and I'm confident yours will run again soon.
 

Mas

Lieutenant Commander
Joined
Oct 3, 2006
Messages
1,656
Re: Help with Evinrude 1974 4HP

how is best way to get a spray. Carb (and choke) is working fine on other outboard.
Ceno

Get a pump spray bottle like the type we use for some cleaning products. Look for a recycle code "HDPE 2." This should be OK to not react to the gasoline...Let a small bit before sit in the bottle before you try spraying it in the carb...just to be sure (you do not want any dissolved plastic shot into your carb!). Also, make sure the bottle you choose has been cleaned throughly to prevent a chemical reaction with previous products. Furthermore, it's not a good idea to store any of the pre-mix in that bottle...drain any left over back in your tank and label the bottle as "Gasoline" to prevent any mistake about its current or previous contents.

MAS
 

tashasdaddy

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51,019
Re: Help with Evinrude 1974 4HP

i do as above, or if a bottle is not available i keep a 18" piece of small fuel line, i just dunk it into the tank, put my thumb on the end. and use it to put fuel into the carb.
 

ceno

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Joined
Mar 12, 2009
Messages
7
Re: Help with Evinrude 1974 4HP

OK its sorted, I bought this as a non runner a few weeks ago from a guy who couldn't get it going with the idea it would be useful as spares. Anyway it looked all there, so I thought I'd try and get it going. I rechecked magneto and carb again on known good motor and reassembled. As discussed earlier I sprayed premix into carb but still only got odd firing. Plugs still never got really wet, so I removed reed valves again. Gaskets came away easy again as they were only stuck on one surface with gasket glue. It was then that I realised the front and back reed box gaskets were switched and was now pressing on reeds stopping them working! Gently peeled gaskets of, cleaned them and replaced correctly and reassembled. Ran first pull! Don't know how long it had been like this, but I reckon it would never have run properly. If only I'd have noticed first time I had removed them.
Thanks for everybodies help, it really helped me focus on the problem.
Ceno
 

tashasdaddy

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51,019
Re: Help with Evinrude 1974 4HP

attention to detail. good eye. congrats.
 
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