evinrude big twin 40553A

[Buccaholic4]

I have an old outboard motor, evinrude big twin 40553A, bought this boat, came with this motor.. any help is always useful

 

[racerone]

If you need help to lift that ( 1965 ? ) motor , most folks on here likely are too far away.

 

[F_R]

40553A is a 1965 Big Twin Electric Start. It left the factory as a long shaft motor, but may have shortened since then (easy). The "A" (sometimes "M") identifies a midyear change involving the shifter components. A parts book will tell which parts are correct for your motor.

Correct fuel mix is 50:1 using TCW-3 outboard oil and regular gas. Lower unit takes any reputable 80-90 weight outboard gear oil. Original spec might possibly have been Type-C oil, but that was only necessary in Selectric Shift models, which you don't have.

Any other questions, just ask.

 

[Scott Danforth]

welcome aboard. and yes, help is useful. however without a specific question to a specific problem we are all guessing as to what help you need

 

[Buccaholic4]

Thank you for everyone that has responded. I'm learning slowly how to work on this motor. I have mechanical expertise as a car mechanic, just short on the two stroke side. so there are three questions. 1. does there have to be a battery hooked up to see spark coming from the coils. I used a jump pack to check starter, it spins, but no spark.(one and two cylinders) 2. is that a inspection plate with teeth on top of the flywheel? (looks like a crown with fins pointed outward. 3. Wonder if I have to take the fly wheel plate off and sand points, gapping .020? They say its been about four years since the boat has seen water. So here goes nothing, bought the boat and trailer for 500.

 

[F_R]

1. No battery needed. It will actually run without one.
2. I think you are talking about the generator belt drive pulley ( generator was an accessory kit)
3. Flywheel has to come off to do any meaningful work on the magneto. It is tough to get off. You need a 3-bolt puller in the holes for the recoil starter ratchet. To reinstall, the tapers MUST be clean and dry, and you MUST use a torque wrench to tighten the nut to 100 ft lbs. Ignore and you will seriously damage some $$$$ parts

 

[F_R]

If you have any thoughts about removing the carburetor, it will be s-o-o-o-o much easier to get it off and on while the flywheel is off. Remove the electric starter along with it's bracket, and the bracket on the other side of the motor. Then the carb is a piece of cake.

 

[oldboat1]

The device on top should be the ratchet for the manual rewind starter. I would pull out the plugs and test compression and spark using the rewind starter, if it's functional. I believe you need about a 3/8" spark for starting, measured with an adjustable open air tester (cheap -- but not the inline type). Need a working thermostat installed for the automatic choke to work.

 

[racerone]

If the model # in post #1 is in fact correct----------I think the 65 model use the " hot air " choke.-------With air drawn through a heat exchanger in the exhaust manifold.------Not the same as the hot water chokes of earlier models.----1963 was the last year of hot water chokes on the 40 HP.

 

[oldboat1]

Thanks, R. -- stand corrected.

 

[jimmbo]

To reinstall, the tapers MUST be clean and dry, and you MUST use a torque wrench to tighten the nut to 100 ft lbs. Ignore and you will seriously damage some $$$$ parts

I can attest to that. In 1974 my dad had our 1963 40 HP in for a tune up. First time run on the water the Flywheel lifted off the Taper. It was prevented from coming completely off and through the Fiberglass Cowl by the Recoil. When the Flywheel came loose it felt like the motor had struck an underwater object, but then it started slowing down until it stopped. I was about 14, and I thought the engine had seized as it wouldn't rotate. After a tow back, and some Inspection by my dad, the recoil was removed and the Flywheel Nut had backed off to where it against the recoil, and the Flywheel with its nasty teeth had jammed against the Recoil housing. A few minutes later we were back on the water with most likely an Over-Torqued Flywheel Nut. Dealer who did the Tune Up didn't seem to care too much when we returned the boat to them

 

[oldboat1]

I learned about torque with a '61 Lark (sheared keys). Had that in hand when I was given a '63 Lark, but never mastered the generator operation -- ran out of belt replacements.

 

[Buccaholic4]

I did compression test using the starter, I saw it was around 65 psi both cylinders. didn't check the gap, on plugs yet. Previous owners had a 1/4 fuel line running from the port, to the fuel pump. it looks like the same from the fuel pump to the carb. took out that line and put 5/16 from port to fuel pump, with an inline filter. I have always loved inline filters, for its clear (absence or presence of fuel) Now I'm running after market, fuel lines that don't match with port or old metal tank. Because of a metal post on both sides. Gotta find away around that, looks like grinding? On the tank, there seems to be a relieve valve and another little metal rod next to it. What are they? Any help is good help....

 

[F_R]

Are you assking about the two little pins on the tank outlet--the ones that get pushed in when you plug on the hose? One is a fuel shut-off valve allowing gas to flow to the hose when plugged on and also to prevent gas from spewing out when the hose is unplugged. The other one is a vent valve. Allows air to enter the tank to replace the gas that is sucked out. Likewise, it also prevents gas from slopping out the vent.

 

[racerone]

Compression of 65 PSI is way too low for that motor.

 

[Buccaholic4]

Thanks supreme (F_R)about the fuel line metal pins information, good stuff, I did hear one hiss when I depressed (one)it. Maybe I'm doing something wrong on compression test. If so, its kinda ironic that both cylinders tested the same, I was told 120 is proper PSI. but then again, I'm using a jump pack straight to the starter that's not fully charged. that could give me a false reading.(bypassed so I don't have to use the key to turn it, or have a second person.

 

[jimmbo]

I highly doubt that 120 is feasible from that engine, it only has about 5.5:1 for a Compression Ratio

 

[Buccaholic4]

What is the recommended PSI?

 

[matt167]

If you get even compression over 80 PSI, It'll run.

 

[racerone]

You would be looking for about 120 PSI on a good one !!