Where's the fuel on the top cylinder? 1984 70hp

[cmuman]

I have been trying to figure out why my 70 hp outboard didn't change when I pulled the top spark plug. I thought it was originally a fuel issue, so I dove into the carburetor. It seemed that the fuel bowl was getting fuel. We took a sprayer with gas/oil and shot it into top cylinder. It seemed to speed up the engine. I took the carburetor off and cleaned the passages and checked the jets. (2 that I could find.) It appeared that I got everything clear. I put the carb back on with hopes and..... same problem.

I then persued electrical. I've got good spark and it seems that every plug is firing good when it should. I put new plugs in the motor, and the top one ended up dry after trying to run it. So...

Then I switched back to fuel. I started it up for a sec to see if squeezing the primer would change anything. No change.

All compression is at 115 on all cylinders.
I cleaned the carb, but didn't put a carb kit on it.

The engine still has no change when you pull the top plug, but pull the other 2 one at a time.

Any ideas? Thanks in advance.

 

[Silvertip]

Re: Where's the fuel on the top cylinder? 1984 70hp

You still have a fuel issue. the main jet or a passage in the carb is blocked. If the engine speeds up by giving it a shot of fuel, you found the issue. You now need to determine the cause. Unfortunately we can't see your carb so you need to ensure every passage is squeaky clean. And just so you know, continuing to run it without fuel means it also not getting oil. No oil causes bad things to happen.

 

[JB]

Re: Where's the fuel on the top cylinder? 1984 70hp

Many "cleaned" carbs are still plugged in the critical orifices, cmuman. The ones that open into the carb throat.

Other possibilities are a reed or a gasket leak in the intake area or bypass.

 

[cmuman]

Re: Where's the fuel on the top cylinder? 1984 70hp

The passage that I couldn't get as clean as I wanted was the skinny tube passage from the bowl up to the throat of the carb in front of the butterfly. Is there any tricks to get this clean? It seems that there is a small hole in this tube right next to the butterfly. I tried cleaning it out, but obviously I need to do better.

I only ran the engine long enough to check the spark and then pull the plugs. Then I figured out myproblems with the carb.

 

[wavrider]

Re: Where's the fuel on the top cylinder? 1984 70hp

Napa carb cleaner in the 1 gallon can, has a basket to soak the parts in.
I have tried all the chemicals, acetone, spray carb cleaner, they both do ok but the high dollar carb parts cleaner from NAPA worked the best.

you need to blow compressed air through the orfices to see if they are clear.

 

[tashasdaddy]

Re: Where's the fuel on the top cylinder? 1984 70hp

i remove my jets, special tool also take a a piece of stranded wire, take 2 or 3 strands, twist together , and run thry the jets, be surprised what the break loose.

 

[cmuman]

Re: Where's the fuel on the top cylinder? 1984 70hp

Is the skinny tube running from the bowl up past the butterfly supposed to come out? Where can I find those jet screw drivers?

 

[tashasdaddy]

Re: Where's the fuel on the top cylinder? 1984 70hp

they are part #317002 +-$18.00 the red/black handle ones i made from a quality screwdriver, with my belt sander, you could use a grinder also. tube, no, blow compressed air up it. or thin wire. that is the high speed pickup, from the high speed jet in the bottom of the carb.

 

[cmuman]

Re: Where's the fuel on the top cylinder? 1984 70hp

I found 2 jets in the top of the carb one behind a short fat screw and one behind a rather long skinny screw. Is that all of them?

When I was looking at the carb kit for my engine, it looked like it came with a gasket for some type of metering circuit. I only found a gasket on the bowl and a small circular one inside the bowl. Am I missing something, or is that gasket not part of my carb?

 

[tashasdaddy]

Re: Where's the fuel on the top cylinder? 1984 70hp

go here, clik parts, clik evinrude, clik 1984, clik 70, clik, carb. the jets are # 29 and 27.http://shop.evinrude.com/

 

[cmuman]

Re: Where's the fuel on the top cylinder? 1984 70hp

The jet looked clear. I will take some twisted wires and clean them out, but how do you know that a jet needs replacement?

 

[tashasdaddy]

Re: Where's the fuel on the top cylinder? 1984 70hp

very rarely do they need replacing.

 

[Willyclay]

Re: Where's the fuel on the top cylinder? 1984 70hp

I removed and cleaned the same carb three times before I could get one of my motors to idle properly. If it doesn't run right, it is not clean. Good luck!

 

[cmuman]

Re: Where's the fuel on the top cylinder? 1984 70hp

Willy, was there a stubborn spot that you found that I might be able to watch for? Did you soak the carb? What finally worked?

 

[Willyclay]

Re: Where's the fuel on the top cylinder? 1984 70hp

My low speed/idle jet had some really hard crud in it that did not come out with soaking & spraying carb cleaner or compressed air. Finally got it out with a needle that I stole from my wife. I've found that brake parts cleaner is very effective also but it will ruin rubber or plastic parts so be careful!

 

[cmuman]

Re: Where's the fuel on the top cylinder? 1984 70hp

I know how potent brake cleaner is. Some fogged on my lawn tractor when my buddy was working in my garage. No fun

 

[cmuman]

Re: Where's the fuel on the top cylinder? 1984 70hp

Which one is the low speed jet? the one in the center above the throat opening or the one off to the side by the vacuum line??

 

[tashasdaddy]

Re: Where's the fuel on the top cylinder? 1984 70hp

are you sure you are working on an 84 70hp? did you look at the diagram i mentioned, both jets are on the front of the carb, low is center top, high center bottom in behind the drain screw on the float bowl
http://shop2.evinrude.com/ext/index.aspx?s1=e25e53dbbe469926656d8fdb0143fec7

 

[cmuman]

Re: Where's the fuel on the top cylinder? 1984 70hp

I'm almost positive that it is a 1984 I pulled out the top center and then I pulled out number 22 on the diagram. I think I might have missed the jet behind the drain plug. What is number 22 then? That is the other jet that I pulled out and cleaned.

here's the link I was looking at

http://shop2.evinrude.com/ext/index.aspx?s1=74ae18f8f076e017d6d22deff1dd7fc3

 

[guy74]

Re: Where's the fuel on the top cylinder? 1984 70hp

Number 27 is the idle jet. I'm not sure what #22 does, maybe it is a midrange fuel orfice. Am I right in assuming that the top cylinder isn't getting fuel at idle, or at least not enough to run on? If that is the case, your problem must be in the idle ciruit, if the float bowl is full of fuel. Make sure you get the #27 jet and the fuel passages going to it clean.
Goodluck,
Brian