No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

[Steve135]

My problem with this motor for the last year has gotten worse! I have narrow it down some more. Compresion is 122,121,122. I have no power above 1500 rpms and then it bogs down and stalls. I rebuilt the #1 carb because of fuel puddling in the throat,no help. I checked all the coils today and found them to be good.All the carbs are synk up. What I did find was that at idle if I place my hand over the carb opening on #1 carb it has no affect at all,the motor runs as if I didn't do anything? I put my hand over #2 or #3 and the motor stalls. So my question is can bad reed valves on that carb be the problem? This engine did have a bad overheat in its life. But ran fine for a 1 season after the rebuild. I am thinking they got hot and lost there spring? Joe Reeves pointed me to a nylon part under the fly wheel last year, could be melted. It was melted good.<br />It was causing the timming not to advance. Thats hot. But remember this engine ran all last year with out problems.<br />steve

 

[OBJ]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Stinky....are any of the carbs puffing out? From the sound of it, your not getting any fuel from the number one carb.

 

[Steve135]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

OBJ the # 1 carb was rebuilt this week because I thought the fuel puddling was a problem. It seems that problem comes from no suction from that cylinder??? When my hand covers that carb theres no pull, but #2#3 has lots of pull so in a way yes not enought fuel is getting to the cylinder at higher rpms. Hence no power. I thing either the reeds are broke or somthing is holding them open?

 

[OBJ]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

You should be able to get a look at the reeds with the carb off. Get a strong flash light and take a look. Serious damage will be apparent.

 

[ob]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

If there is little or no vacuum from that carb ,I think that having a looksee at the reeds is very logical.

 

[DHPMARINE]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

If the reeds were bad they would be stuck,bent or broken,so as to be open.As the piston travels down,it would spray fuel OUT of the throttle bore.If this isn't occuring,fuel probably isn't getting out of the carb when it should.Look for a bad crank seal letting air in,or possibly worn piston skirts.<br />DHP

 

[Steve135]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Hi all thanks for the good info. Yes fuel does spray out a little of the #1 carb.Yes there isn't any suction on that carb.If it was a crank seal wouldn't it afect all three carbs? Worn piston skirts??? I have a set of red valves off a 60 hp Johnson are these the same? I would like to just swap them out to see if its the problem. Then I'll order the new sets.<br />steve

 

[Steve135]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Hi all, I have the motor running correct again. But I don't know why? I went to the reed valves for tht number 1 carb and saw nothing alarming I touch them to see if they were free moving, they were. I started to take off the intake but it was pretty stuck in place and I didn't have a new gasket. So I never remove it and just retorked the bolts. Put everything back together and it runs great? I will do a run tomorrow and see for sure,as it has in the past run for a couple of weeks and then act up??<br />Thanks steve

 

[kshelly]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Gotta love an engine that fixes itself!!!!!!!

 

[Steve135]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Hi I thought it was fixed but not! I took it out today and it ran fine for the same amount of time as before. Then it bogs down. I try to pump the throttle and it worked to bring it back up to speed. Then after 20 minutes of WOT it slowed , <br />I was able to get it back to WOT by pumping again. I was sraying sea foam in the carb as I went along Im did see some improvement in the #2 carb as a sprayed. I will rebuild #2 and #3 as well now. I have done everthing <br />A. Electrical<br />1. Swapped spark plugs<br />2. swapped plug wires<br />3. swapped coils (wiring was modified so that power pack would fire correct coil)<br />4. checked spark to ground (3/8 inch plus spark, both cyls.)<br />6. Checked battery voltage; 12+ volts<br />7. Inspect and reseat connectors<br /><br />B. Mechanical<br />1. Disassemble, clean, and check carbs, matched float levels<br />2. swapped carbs<br />3. swapped V-box reed plate assemblies<br />4. Installed new fuel pump kit<br />6. Squit fuel directly into upper carb (at idle)<br />7. Inspect upper crankcase seal; packed around seal with petroleum jelly, ran motor, then reinspect seal for signs of a vacuum leak or blow by<br />8. Checked stator for possible rubbing on flywheel.<br />9. Carb air flow test; by holding a piece of paper 1 inch or so in front of the carbs, a fine mist of fuel was visible on the paper. Covering the carb with paper; on #2 cyl a puddle of fuel would develop at the carb opening and the motor dies, #1 cyl a fuel puddle developed but the motor would continue to run. <br />Help

 

[Chinewalker]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Intermittent problem sounds to me, exactly like what my 3-cylinder did when the power pack was going south. I could check for spark at the dock and it looked fine. Under compression it would drop one cylinder. If you know someone with a similar motor, see if they'll let you borrow their power pack and swap it in... Doesn't take but a few minutes and you'll know fairly quickly...<br />- Scott

 

[Steve135]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Hey Scott I was thinking the same thing I have a 1991 70 Evinrude that runs perfect. And I just order a new power pack for the motor.I read a post the other day that turned out to be a stator problem. I did overheat this motor a year ago and most of this has happened after that. I did rebuild the whole thing and replace the pack with a new used one as the old one was toast! I did notice one other thing. I can rev the engine in idle and then place it in gear while the rpms are still high and it will take right off, almost like the prop is too big. Its a 13 x 19<br />steve

 

[Steve135]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Hi I haven't recieved to power pack yet so I am going ahead and rebuilding the #2 #3 carbs as the was an increase in rpm when I shot sea foam in #2 at 2500 rmps in gear! I am thinking it could be the float as well because I put the carbs in a bucket as I was working on the motor. Maybe I drop one too hard and this is why it worked the first run after I did all that work? Now its back to the same old Boging down.<br />steve

 

[Steve135]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Hi, Rebuilt the carbs #2 #3 and it ran bad there was no spark on # 2 cylinder? I changed out the power pack for a NIB one and it wouldn't even start this time. The boat comes out of the water tomorrow. I think its has to do with the stator from the overheat last year. I am either going to change the motor with one I have extra and trouble shoot this one as I can. Or I just have to live with one boat this year!<br />steve

 

[Steve135]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

Well the starting problem was a bad rectifier. I wore the batteries down and thats was giving me fits with power. I also think I have a stator problem or trigger problem as this motor still won't get above 1500 rps in gear. What kills me is I can pump the throttle and get it to about 2500 rpms and somtimes even 5000 in gear and then when I slow it starts all over again.I pulled it off the boat and put a 1991 70 hp rude I had hanging on the stand. This motor has a lot more throttle responce than the 70 hp 1984 this is making me believe its a timing issue or electrial power problem. I will work it over the summer, or just part it out? <br />thanks steve

 

[phatmanmike]

Re: No power 1984 70 Evinrude Time to Shoot it! . Pulled it from the boat

i agree sounds like vacuum leak at number one carb... try switching carbs with number 2 ro 3 cylinder see if it changes anything, if it does , its your carb