1964 40 hp compresion test.

[hyspenc]

hi guy's
Well i have just started to work on my old 64 RDS-26S 40 hp
and with all the good info off of this forum,i did do a compresion test on upper and lower cyl in fack i did it twice.
The reading i got was 90lb in both cyl.
Not sure what it should be but most folks on this site say as long as they read close to the same it should be oka
Just was looking into some feed back as to what you all think is it worth rebuildingthe carb and before i start to disasemdle the pull start to seeif coils are fried as i was having trouble earler last summer with the boat doggen at times and then not at other times someone mentioned pumb ball and fule pump. and also coils so any insite would be gladly app.
O ya serial #C397061.
As long as i am here i would just add that i seen a carb on e-bay for 50.00
owner say's it was rebuilt buy a shop,with a new float.
What do you think would it be easer to swap if it would fit it's off of a 1960 40 hp.
O and Happy New years

 

[F_R]

Re: 1964 40 hp compresion test.

1960 carb won't work on a '64 without a lot of other changes because the automatic choke is way different.

Besides, it would be dumb to throw a carburetor at it without doing basic troubleshooting first. Your intermittant power loss is more likey to be ignition problems.

 

[hyspenc]

Re: 1964 40 hp compresion test.

thanks sport but nothing i do is dum.

 

[HighTrim]

Re: 1964 40 hp compresion test.

I would follow Franks advice here, as I have learned from him myself, check the coils on these first. You are likely loosing spark as he mentioned. Have you in fact tested the spark with an inline tester set to 1/4"? Should jump the gap with a bright blue ZAP!! Your compression is fine.

Test your ignition system, if it fires as it should, look to fuel delivery.

 

[F_R]

Re: 1964 40 hp compresion test.

thanks sport but nothing i do is dum.

Glad to hear that. So that means you won't start now.

 

[tashasdaddy]

Re: 1964 40 hp compresion test.

hyspenc, F_R is one of the Guru's for the older motors, i agree with his statement. there is nothing to rebuilding that carb, and cheaper than buying the wrong carb. which if it was used at all, will probably need cleaning and a kit. this kit will work fine. http://www.iboats.com/mall/partfind...gd_poid=109330&gd_row=44&**********=927079436

http://forums.iboats.com/showthread.php?t=244013

 

[hyspenc]

Re: 1964 40 hp compresion test.

Thank-you for all the good info.
I will rebuid the carb. now,because as i was poking around getting a look at the carb i noticed that the choke was lose it is a water choke,type 2.
I have no idea how this would happen,as all of the 3 screws used to fasten the choke to the carb were out and laying inside the housing allong with the other components all are still there but will rebuild carb *** soon as i get kit.

Will also take the flywheel off of motor this morning and have a look at the coils and points.
Do you think all of my lack of power and then sudden surge of power would be all choke related?
there is an awfull lot of resedue inside the cowal and at exhust.so yes will rebuild carb.
thanks again will keep you posted if interested

 

[tashasdaddy]

Re: 1964 40 hp compresion test.

PULLING FLYWHEEL

you need a harmonic balancer puller, you need 3 - #8 harden bolts, that fit the 3 holes in your flywheel. standard hardware store bolts will strip out, causing more problems. loosen the flywheel nut, leaving it on so it protects the thread. thread the bolts in 7/16 of an inch. then tighten the puller, adjust so it has a straight pull. now tighten the puller, rap the center bolt with a hammer, then tighten some more. you may have to let it sit over nite, and repeat in the morning. this is a compression fitting, it will eventually POP!!. do not loose the woodruff key that goes in the groove of the flywheel and the crank shaft. then installing the flywheel, it has to be totally clean, no oil, woodruff key in place. then torque the nut to the specifications for your particular motor. if you do not do this, the woodruff key with shear, and you will be repeating these steps.

 

[F_R]

Re: 1964 40 hp compresion test.

Flywheel nut torque is 100-105 ft/lbs. I've seen those chokes come loose before. I think it is just vibration that does it. Put a drop of Loctite on the screws when you reinstall it.

EDIT: I just noticed. You say it is a hot water choke. I was thinking that 1964 was the year that they went to a hot air choke. That was the basis for my comment that the 1960 won't work. Am I wrong on this? I don't have the 1964 parts book to check it out.

 

[F_R]

Re: 1964 40 hp compresion test.

Just for the record....

 

[Evinrude Boater]

Re: 1964 40 hp compresion test.

I was thinking that 1964 was the year that they went to a hot air choke.

I think you're right. I have two 75 hp engines, the '63 is hot water and the '64 is hot air. We discussed the differences in the carbs.

 

[steelespike]

Re: 1964 40 hp compresion test.

To get back to your compression 90 is a little low but a good decarb treatment may improve things.It shouldn't be a problem.

 

[tashasdaddy]

Re: 1964 40 hp compresion test.

Decarb, take a can of seafoam put 3/4 of it in the gas tank, with only 1 gallon of premixed gas. put the rest in a spray bottle. start the engine, and let it come up to temperature. then remove plugs, and them some real good shot of seafoam into the cylinders, replace plugs, let sit 15 minutes. restart, and spray the rest of the seafoam into the carbs, so the the motor almost stalls, wait and repeat until the seafoam is gone.then take for a wide open spin. then put in new plugs, ad premixed gas to the tank, and take it for a wide open throttle spin. it is going to smoke like a house on fire, during this process.

afterwards compression.recheck

 

[hyspenc]

Re: 1964 40 hp compresion test.

hy guys
F R is right after looking at the thumb nail pic's and what i have it is a hot air choke, so i know now , i do have a parts cat, for tha motor in qustion,and a silco service manual, but i realy have a lot of good tips right here thanks again.
I have the pull start off and the main fly wheel nut lose, and was about to take off fly wheel but the harmonic balancer puller that i bought dose not have the corect size bolt that i need so i am off to hardware store to find them #8 harden ,
I don't under stand why the threads are so exposed on the main fly wheel bolt when i thread the duck foot on to the bolt should i leve it just up from the fly wheel so it has room to lift and if i leve the nut attached to bolt how do i thread the duck foot on?
Thanks again will get back to you later

 

[hyspenc]

Re: 1964 40 hp compresion test.

hello again,
Just now got the fly wheel off, was pretty easy.
with no test just visuale at contacts and coil's they look to be in good shape.
I know they say that contacts should be srviced about every 100 hr. of use,
but i really didn't have a start prob just wot, and slow speed and fule consuption prob.
What do think replace point and codensor's or focus on carb issue?
I don't think this motor has much time on it as everything is to clean,
Bought it in june 08 fellow said it was involved in one of those devorce issues
and sat around in garage for a few years till he got it off of his uncle.
Well any way i like the hole deal and i think i'll tackle carb and water pump for now and wait till spring and try it out.
if i get stuck hope you all will help out thanks again

 

[tx1961whaler]

Re: 1964 40 hp compresion test.

I didn't quite get all of what you're doing, but to pull the flywheel:
Take the flywheel nut off.
Thread the puller's main bolt through the threaded center hole of the "duck foot". Thread the puller's bolt almost all of the length of the puller's bolt. The flat side of the puller faces down toward the flywheel.
Put the foot of the puller bolt on top of the flywheel's shaft.
THread the (3) 1/4"-20 grade 8 bolts through the puller's "Toes" into the 3 holes in the flywheel and tighten evenly down at least 1/2 "
Tighten down the pullers center bolt and make sure everything's even, then start cranking the puller's bolt. The flywheel will eventually pop off

 

[F_R]

Re: 1964 40 hp compresion test.

It is impossible to say what the problem is from here. Look for dirty points, points out of adjustment, cracks in the coils, etc. A hidden stumper is the spark plug wire often arcs through where it is clamped to the bottom of the armature plate. You can't see that without taking it apart, and even then it is only a nearly invisable pin hole through the insulation. You HAVE tried new spark plugs, right?

I can't say that you don't have a carburetor problem, but 90% of intermittant drop off to about half power or less is because you are dropping one cylinder. The carburetor feeds both cylinders, so it won't cause that.

 

[hyspenc]

Re: 1964 40 hp compresion test.

thank's guy's
And f_r upon closer inspection of the point's, i found that the #2 cyl point set was out of addjustment to the best of my knowlage.
Also found that the condensior on the same point set was lose i can remove it from the space provided in the mag plate.
I removed the outer cover that covers exhaust boot and found a lot of discarded material such as a pice of coil leed wire a bolt and some pices of an unknown part. Wow some guy's are really sloppy i allso found what look like a malloroy part with the number c0397061 I think that a previous owner had at least one coil blow on him, i tried typing this # in at johnson outboard motors and it comes back with no pic but say's it is a L/p i have know idea what it came from or if it is now missing off of my motor,.

Any thougt's on what it came from would be appreciated,It kind of look's like an old frost plug or some thing it is the size of a quarter and convexed .
O and yep i am replacing point's and condensior's

 

[tashasdaddy]

Re: 1964 40 hp compresion test.

i find more crap in the lower pan of motors. glad you are doing the electrics.

 

[hyspenc]

Re: 1964 40 hp compresion test.

Hi tassh well after you and F_r voiced your oppinon on the coil and related parts and what i seen it makes cense to replace them.

I am doing the carb coils and breakers, water pump,and thermostat,
I think with a little paciantes and time iwill be ready for spring.

I have one new thing to add,
When i order carb kit dose the float and new low speed needle valve come with or is that a seperate part,

And is Sierra as good or good enough after market parts thanOMC?

Thanks again for all of your and the guys thoughts on my concern's