1987 40hp evinrude vro (oil deleted) carb issue?

[saltchuckmatt]

Buy a used carb....Tims outboard service. Don't give up on this motor, new ones are not the answer.

timsoutboard.com

 

[Shwinkyyy]

You will be delighted with a new 4 stroke.-----Computor does all the thinking for you.------Trouble free boating with a 4 stroke until there is trouble.

So I just got off the phone with the mechanic. He is telling me to not even bother putting any more money into this motor. He started to explain that the motor is probably shot, saying that the bottom skirts of the pistons are probably worn to where the block is getting no vacuum, he also explained further that I would still get fair compression readings with this problem given that the top end of the piston is still ok. He also stated it is one of the most common problems with this motor after its worn down over the years.
Does this sound like an accurate statement to all of you? I would hate to keep spinning my wheels on this if that is the case, money would be better getting saved up for a new one.

 

[racerone]

See post #18-----Taking the cylinder head off to inspect cylinders is the quickest / easiest / most cost effective step in trouble shooting.----Very few people can accept this simple fact.

 

[saltchuckmatt]

Remove the exhaust housing.

 

[Shwinkyyy]

See post #18-----Taking the cylinder head off to inspect cylinders is the quickest / easiest / most cost effective step in trouble shooting.----Very few people can accept this simple fact.

Message received, I have seen you say this before in multiple posts. I will probably go that route next given I am out of options at this point (what is there to lose). If I do so I will be sure to take some pictures and video and post them up here. Thank you so much for your time, your a huge help to everyone here and I'm sure you don't hear that enough.

 

[saltchuckmatt]

Skirts are bad so pull the head?

Hmmm.....ok

Most mech these days will give you 50 reasons to throw it away.

 

[Shwinkyyy]

Alright time for an update, I haven't given up on the motor guys don't worry. I was just venting out of frustration before. I went ahead and did a full rebuild on the Carbs. I am now leaps and bounds closer than before.
It is idling again now, the Idle is a little rough it doesn't seem too happy.
Alot of progress on running throttle open, so it will now let me run wide open at first, it doesn't cut out dead anymore but after about 1 second i get a loss of power, it doesn't stall out if I had to guess i would say it bogs down to about half throttle worth of power? I drop the throttle and open back up and same thing she will open up for a second then bog back down. But it doesn't stall at all through the whole process, it will stay running.

I also went ahead and ran another compression test since she was warm and I figured why not. I got 140psi on both cylinders.

OVERVIEW:
REBUILT CARBURATORS
INSTALLED NEW FUEL PUMP AND LINES
NEW SPARK PLUGS (CHAMPION)
GAPPED SPARK PLUGS, 30 OVER
FLUSHED OUT OLD FUEL IN TANK, REPLACED WITH NEW FUEL AND SEA FOAM.

the last factor I haven't covered and I feel it's going to end up here is link and sync. I don't know how to do this, is this something I can achieve? Or am I going to have to rely on someone with more expertise?

 

[airshot]

Alright time for an update, I haven't given up on the motor guys don't worry. I was just venting out of frustration before. I went ahead and did a full rebuild on the Carbs. I am now leaps and bounds closer than before.
It is idling again now, the Idle is a little rough it doesn't seem too happy.
Alot of progress on running throttle open, so it will now let me run wide open at first, it doesn't cut out dead anymore but after about 1 second i get a loss of power, it doesn't stall out if I had to guess i would say it bogs down to about half throttle worth of power? I drop the throttle and open back up and same thing she will open up for a second then bog back down. But it doesn't stall at all through the whole process, it will stay running.

I also went ahead and ran another compression test since she was warm and I figured why not. I got 140psi on both cylinders.

OVERVIEW:
REBUILT CARBURATORS
INSTALLED NEW FUEL PUMP AND LINES
NEW SPARK PLUGS (CHAMPION)
GAPPED SPARK PLUGS, 30 OVER
FLUSHED OUT OLD FUEL IN TANK, REPLACED WITH NEW FUEL AND SEA FOAM.

the last factor I haven't covered and I feel it's going to end up here is link and sync. I don't know how to do this, is this something I can achieve? Or am I going to have to rely on someone with more expertise?

Very doable yourself, but you need a factory service manual for the steps and follow them to the letter !

 

[Shwinkyyy]

Very doable yourself, but you need a factory service manual for the steps and follow them to the letter !

I still have the original user manual for this motor I take it that will have my information?

 

[Shwinkyyy]

So I attempted to take it out on the water again today, and it was a colossal failure. Put it in and it was running at first. Still has rough idle but I was able to get it in gear and move at low rpm, went to open up throttle and it bogged down and died on me. after cutting out it would not start again for a few minutes. After sitting for a bit it fired up again but still idling rough and cutting out (idle also seems low). Now it's just having a rough time all around to keep running, it almost seems like too much fuel now.

Primer ball is staying stiff
Floats for carbs are adjusted properly
Carbs are CLEAN, it's not gonna get any cleaner.
Fuel enrichment valve is at 3 o clock position
Butterfly valves are opening at same time, and also at full horizontal at WOT.
it seems like the motor gets more pissed off the warmer I get it.
I'm completely lost and I'm not sure what to do at all at this point.

I wasn't able to try pushing the key in while throttling as the motor was giving me too many problems to stay running, so I cannot give any information on that detail.

The rough idle doesn't have a lean sneeze any more either it's a different kind of rough if you can understand what I am trying to say.

 

[racerone]

Red lever must be inline with valve body to run.

 

[airshot]

I still have the original user manual for this motor I take it that will have my information?

User manual means nothing. The factory service manual is what a service tech uses uses to service the motor. It will have all the adjustment and setup specs you will need.

 

[Shwinkyyy]

Red lever must be inline with valve body to run.

It wasn't running then either. I wish that was the answer.

 

[ct1762@gmail.com]

Ok thank you so much for the feedback, I am going to mess with them some more today. I will make sure to get pictures and post them here so maybe you guys can see something I cant.

as mentioned make sure the tiny idle pickup tube is 100% clear and alcohol or carb cleaner sprays out the tiny little idle calibration holes on the rearward "roof" of the carb just behind the throttle butterfly's. will need to hold them open to check while spraying. once together, manually blow into the carb with it upside down. should NOT be able to blow into it. now gently tip it right side up. is it clear/easy to blow into? this eliminates any needle sealing issues.