1986 evinrude 140 question

[gregr1971]

what should the cranking compression be? i am getting 115 per hole. i am told this is too high.
now i also have a 1991 200 johnson, also loop charged, it is reading approx. 75-80psi per hole, and my local mechanic said it needs rebuilt due to low compression. BUT it runs perfect!
what psi should these engine be at??

 

[bgbass.1]

Re: 1986 evinrude 140 question

The 115 is good compression the 85-90 is a little low try doing a decarb. then check it above 100 is ok all cylinders should be close to each other thats the main thing

 

[tashasdaddy]

Re: 1986 evinrude 140 question

were both motors check with the same guage? turnover till the guage, quit going up? the reason the 200 runs well, is that the compression on all cylinders are close in value. guages are all different. the main thing is that the numbers are with in 10% of each other. i would do a decarb on each motor, and then recheck with the same guage.

decarbing:
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 recheck compression.

 

[Dhadley]

Re: 1986 evinrude 140 question

Basically your mechanic doesn't have a clear understanding of how port timing affects static compression readings. Both are fine. I would suspect the 200 is being lugged and may have started to stick some rings but a decarb job will take care of that.

 

[gregr1971]

Re: 1986 evinrude 140 question

i have decarbed both engines, and no change in the numbers, but i did notice the 140 has a "pop" coming from the lower right carb. ?????

 

[Joe Reeves]

Re: 1986 evinrude 140 question

The "pop" or "spit back" at the carburetor indicates that carburetor is running lean. With the engine idling, stick two fingers into the carburetor throat, acting as a manual choke. If the engine smooths out and the popping ceases, either the idle airbleed jet's ID is slightly too large OR some other related problem exists...... clogged fuel passage, poor seal between carb and throttle body, reed not sealing properly, etc.

The compression on the later model V6 engines usually vary between banks. The normal readings that I've encountered were approximately 95 psi on the starboard bank and 90 psi on the port bank.

 

[gregr1971]

Re: 1986 evinrude 140 question

ok, new problem!! i tore down the carbs to clean and rebuild, i did not realize that the air bleeds were of different sizes!!! now, which ones go where!!

i also pulled the manifolds(throttle bodies) and replaced all of the gaskets, but failed to inspect the reed valves, if i tear all of that back off, i am going in and replacing the reed valves with the oyesen power reeds. if i do that, should i re jet??

 

[gregr1971]

Re: 1986 evinrude 140 question

i have 4 air bleeds that are #28, 2 are #16, and 2 are #20. ???
do the 28's go in the top holes or the bottom??
and the other 4 ??

 

[tashasdaddy]

Re: 1986 evinrude 140 question

this is what the brp parts diagram says, it take 4 No.28

0322936
Add to pick list ORIFICE, Idle air bleed, No. 28 1 4 140 Models Only


0319907
Add to pick list ORIFICE, High speed, No. 61D 2 4 140 Models Only

0333243
Add to pick list ORIFICE, Intermediate, No. 16, starboard 2 4 140 Models Only

0324005
Add to pick list ORIFICE, Intermediate, No. 20, port 2 4 140 Models Only

 

[gregr1971]

Re: 1986 evinrude 140 question

i know port is left and starbord is right, but is that looking at the carbs, or looking at the plugs??

 

[jdshort98]

Re: 1986 evinrude 140 question

Standing behind the boat, looking forward to the front of the boat. Port is the left side of the boat. Always is, no matter which was you are facing.

 

[gregr1971]

Re: 1986 evinrude 140 question

thanks.
so the small orifices go in the top, and the 28's go in the bottom correct?

 

[guy74]

Re: 1986 evinrude 140 question

Yes, I think you are on the right track. The idle air bleeds are under the intermediate orfices. You can lookup the parts breakdown at "http://www.evinrude.com/en-US/Accessories/Literature/?popup=true"

 

[gregr1971]

Re: 1986 evinrude 140 question

ok, i got it all back together, and it still has the pop on the port carbs, and still idles at 2000rpm! i pulled the reeds and inspected every one, all are sealing, replaced all of the gasgets from the reeds forward, no air leaks. installed the air bleeds in the correct holes and banks, my floats are set at 1/32 above the float bowl, hi-speed jets are 61d, using QL77JC4 plugs.
it just idles high, pops, coughs??? i also pulled the flywheel to see if the magnets have come loose, and they are fine.
NOW I AM OFFICIALLY LOST!!! and i want to go fishing!!!
i am using a clymers manual, but have an omc manual on the way.

 

[seabasser]

Re: 1986 evinrude 140 question

if you are idleing that fast have you checked to see if your timing base is stuck??

 

[gregr1971]

Re: 1986 evinrude 140 question

yes, i pulled all of that off, cleaned and lubed the timer base, works like new.

 

[gregr1971]

Re: 1986 evinrude 140 question

it has some type of aftermarket heads on it , they are a redish aluminum, with 2 sets of plug holes, but, one set of holes is plugged off, all i can see number wise on them is "land&sea 48cc" ????
could these be poing a problem??

 

[flabum]

Re: 1986 evinrude 140 question

There is the reason for your higher compression readings. Those are Hi Perf heads....more compression. Have you done a link and sync and set the idle timing? all this needs to be done in the water for backpressure.

 

[gregr1971]

Re: 1986 evinrude 140 question

i did the sync & lync, i have a 220 gallon stock tank that i did it in.
now it does not have a steady idle, it moreless fluctuates, i wonder if the power pack may be going haywire?? does it control the timing someway??
i have the square pack on top of the port cylinders. p/n 583041 - 6700

 

[reeldutch]

Re: 1986 evinrude 140 question

also check for crankcase leakage.

get a boltle of carb cleaner and spray it around the block and crankcase mating surfaces. with engine idling.
if your crankcase leaks you wil defenatly see a change in engine behavior when you spray the carb cleaner.

high idle and sneezing could be a crankcase leak.
somewere.