Helllo all , help with hic up on 1996 +/- Evenrude 50 HP

Hello Everyone, I appreciate in advance any help you can give me .

This link below has 2 videos, .. on of them has the engine "running"

https://photos.google.com/share/AF1...?key=OVFpbEpjMjVlcUd0U0JMWjJZN3p1MVNHRWYzZ1dR

The second video, 1:39 long shows the hic up happening.. it runs well but every few seconds .. that is a "pop" and the rpm drops. I even have a part of that video showing the tachometer, drop form .. 1050 to like 800.

I would love to know where to start, any ideas folks?

The other video shows a bit of teh starting problem, . but I think it is related, -- when it first starts, IF the engine has a hic up , it will stall out.

CHEERS!
PS- it is a 50 HP evenrude, I think it is 1995, not sure though .. might be +/- a year or 2. I have looked for serial numbers ect at the places they should be, and I can't find any.
PPS- can someone confirm you can even see those videos? not sure I shared them right.

start with the basic checks.
Do you have good compression?
Do you have clean fuel?
Do you have a well timed spark that can jump the required gap?

Serial Number?

The vids are fine mate.

The model number is required in order to pinpoint the year, make, hp of the engine.

A "hic" (spitting back at the carburetor area) at idle is normally caused by a lean mixture... carburetor slightly fouled or out of adjustment if equipped with adjustable slow speed needle valves.

With the engine running and the problem existing... stick two fingers into the carburetor throat to richen the mixture. If a lean mixture is the cause of the problem, and if this finger trick cause the engine to smooth out when done on a particular carburetor... you've found the offending carburetor.

That would be the 3 cylinder and according to the cowling a 96 / 97 model.-----The compression values should be posted first.

The videos are visible.

This shouldn't have anything to do with you hiccup, but do you have hose muffs on the lower unit while submerged in the tub? If so, there's no need for that. Have the tub positioned so the top rim is above the cavitation plate. Fill the tub with water to the top and leave the hose in there. As the engine runs, leave the hose on a little bit so you get a constant trickle of fresh water coming in. This let's the water pump do it's job rather than falsely pushing cold water through the engine.

Do you know if the thermostat is installed and is working properly? I say the muffs shouldn't have anything to do with the hiccup, but if you have no thermostat (or it's stuck open) and you're forcing cold water through the engine it will run colder than optimal and could affect it. A cold engine needs more fuel (i.e. choke) so if the motor is staying too cold it could be running lean.

Poor fuel delivery due a dirty carb(s) is the most likely culprit. But, check your t-stat and remove the hose muffs then try running again.

KJ

Dang old plastic top carbs...the gaskets get hard and loose their seal.

hello everyone, life got in the way , but I am not back at it. Still have that same Hicup problem, someone asked for compression tests.. so here is the data.
in PSI all spark plugs out, battery charged, test done at "idle" setting and at wide open throttle.

Top - 100-@idle 100@WOT
*Middle 90@idle 95@WOT
Bottom 108@idle 110@WOT

Having seen that middle is low, I retested.
middle test 2 - 98@idle 95@WOT
middle test 3 - 100@idle

So what should I look for next.

I have also taken a bunch of photos, because I might want to re build carbs, or fuel pump or something else, and I can't figure out the model number for the engine. please let me know if you can help out with that.

This link should take you to google photos of the engine.
https://photos.app.goo.gl/H7Vjf43FL2oKqAE8A
Please note, there is a supposed to be a plate of some sort, to say what it is, . but 98% of it is missing.

HI all , life got in teh way, and now I am back at it. A compression test was requested, below are the results.

Measurements are in PSI, test was done both "at idle" setting and WOT

Top Cyl - 100@idle 100@WOT
Mid Cyl - 90@idle 95@WOT
Bottom Cyl - 108@idle 110@WOT

I noticed that the middle was rather low, so I re did the test. - I am told that adding liquid to the cylinder might make it preform better, so maybe that is what changed??? below is the second, and third test

Mid Cyl Test 2 - 98@idle 100@WOT
Mid Cyl Test 3 - 100+/-@ idle

How do these numbers look? I think they are a bit low, . I was reading that typical numbers are about 125. The engine was cold, . like barely above freezeing. about .. 6 degree C .

Thoughts?
What do I check next?
Ideas?


Also, haveing issues identifying engine, for new parts. Please see link below for photos, the sticker is mostly gone, but maybe you guys recognize it?

HI all , life got in teh way, and now I am back at it. A compression test was requested, below are the results.

Measurements are in PSI, test was done both "at idle" setting and WOT

Top Cyl - 100@idle 100@WOT
Mid Cyl - 90@idle 95@WOT
Bottom Cyl - 108@idle 110@WOT

I noticed that the middle was rather low, so I re did the test. - I am told that adding liquid to the cylinder might make it preform better, so maybe that is what changed??? below is the second, and third test

Mid Cyl Test 2 - 98@idle 100@WOT
Mid Cyl Test 3 - 100+/-@ idle

How do these numbers look? I think they are a bit low, . I was reading that typical numbers are about 125. The engine was cold, . like barely above freezeing. about .. 6 degree C .

Thoughts?
What do I check next?
Ideas?


Also, haveing issues identifying engine, for new parts. Please see link below for photos, the sticker is mostly gone, but maybe you guys recognize it?

Wow, not bad. Which spark plug is the lightest in color? Low speed screw on that cylinder open 1/4 turn. You showed us the low speed screw.

What am I missing here? The thread date of 02/20/2018 is roughly just three weeks shy of being 1 year old... is it not?

joereeves said:

What am I missing here? The thread date of 02/20/2018 is roughly just three weeks shy of being 1 year old... is it not?

Click to expand...

Yep. Sounds like the OP had other 'life' things come up so getting this engine running went on the back burner until now.

The compression is a little low but my biggest concern is the 16% difference between the middle cylinder and the bottom cylinder.

Most know that there were issues with # 2 cylinder on those.------Take the head off and have a look in there.

joereeves said:

What am I missing here? The thread date of 02/20/2018 is roughly just three weeks shy of being 1 year old... is it not?

Click to expand...

I own a small business with like 4 people working with me. 1 quit, 1 had to be fired (quit before I had the chance). Unfortunately that happened right when we were to start our season , and it wiped out a year of my life , basically.

Hopefully this year will be better.

kevinj said:

Yep. Sounds like the OP had other 'life' things come up so getting this engine running went on the back burner until now.

The compression is a little low but my biggest concern is the 16% difference between the middle cylinder and the bottom cylinder.

Click to expand...

I noticed that as well. So that is why I re did the tests ( after I did bottom Cyl). do you think the new test numbers ( they are in that post as test 2 and 3), change your opinion, or are the additional tests flawed for some reason?

racerone said:

Most know that there were issues with # 2 cylinder on those.------Take the head off and have a look in there.

Click to expand...

That might be a step farther then I am comfortable with, but if I did , what would I do with that, what would I look for. I am a bit of a noob on the mechanical side.

Can't tell by the video, but perhaps it's been changed already. What kind of "liquid" did you put into that cylinder to bring up the compression? Seems the cylinder was dry. Is the spark plug a different color in cylinder #2?
I had a partnership in a fair size machine shop with my brother. Had a drunk, woman chaser, and mad scientist for machinists. That's right, all 3 had great skills. We built some awesome race engines too, but the profits are in heavy equipment work. Had a lathe to handle crankshafts to 12 feet long. I bailed out after 2 years. Don't really enjoy babysitting adults that should be more responsible......after all, it's their job. My brother lost the shop to the bank 2 years later. Live and learn, eh? Now it's my wife, my son and me. Good business.

I see you are familiar with the rigors of business, its a lonely place, nice to know other have it just as rough.

The "liquid" .. I didn't intentionally add anythig ... the engine was being turned over with starter ( no sparkplugs) I am guessing, . that as I ran the engine, some gas was put in to cyliander. I might be wrong, I am hypothesizing this as a possible reason the second measurements where better then the first.

All spark plug looked the same, they were smooth black covered, but I don't really find this surprising as for the last 2 tanks of fuel it was only sitting at idel, and not hot enough to burn that carbon off. I do not think the issue is the sparks, because I changed them out like 3 years ago , it makes no difference at all.
Someone mentioned a "typical" cyliander 2 issue, I don't know what that might be, and I can't find any comments online about that.

timguy said:

Can't tell by the video, but perhaps it's been changed already. What kind of "liquid" did you put into that cylinder to bring up the compression? Seems the cylinder was dry. Is the spark plug a different color in cylinder #2?
I had a partnership in a fair size machine shop with my brother. Had a drunk, woman chaser, and mad scientist for machinists. That's right, all 3 had great skills. We built some awesome race engines too, but the profits are in heavy equipment work. Had a lathe to handle crankshafts to 12 feet long. I bailed out after 2 years. Don't really enjoy babysitting adults that should be more responsible......after all, it's their job. My brother lost the shop to the bank 2 years later. Live and learn, eh? Now it's my wife, my son and me. Good business.

Click to expand...

The center cylinders can score on these, well more often than #1 and #3. Okay time for mechanic in a bottle. Get yourself a bottle of Amsoil Quick Shot and a quart of Amsoil 100:1 pre mix 2 stroke oil. Follow directions. Use 91 octane or better, fresh non oxy fuel with the Amsoil 100:1 pre mix and Quik Shot too. Turn in low speed needles while you count the turns, and take the number down. SEAT THEM LIGHTLY. They should all be within 1/4 turn apart. Report back with your findings. Then after we decide on a good setting for all of them, you can test run. If after that first tank of gas it doesn't run better than ever, I'll send you your money back for the Amsoil. Probably about 25 bucks. Now how is that for a good deal?

thanks Tim guy , I appreciate the help, I will give that a try. I did run some seafoam through it last summer. It is -20c at the moment here, so I will not be able to do this for a few months, unless we get a Chinook, but I will give it a try and report back . I appreciate your comments, I really do.

no suggestion of carb or fuel pump rebuilds?

Yes, that might be a solution, but first try the Quik Shot, it is way better than Sea Foam. I have used both. If you soak a crusty, oxidized part in a sample of Quik Shot....even heavily diluted with fuel......, you will see what I mean. Yup. -20 here too and snowing again.
My 74 Chev pickup was sitting, unused (outside), with ethanol fuel in it for 5 years. Towed it up to my shop and drilled a hole in the corner of the fuel tank, raised up truck, and drained every last drop of that stinking ugly fuel. Next, took out both fuel filters up on intake by the 4 barrel carb. They looked fair. Next, added fresh non oxy fuel with Quik Shot (double strength) than recommended. Then sucked some gas up with an electric fuel pump at the manifold......pulling the fresh mixture through the engine's mechanical pump. Got some crap out into a coffee can. I did this a couple times. Next, I put 2 new fuel filters on and hooked up line to carb. This is a Rochester Quadrajet and I never even opened it up to look inside as the old filters didn't look so bad. I really wanted to open the carb but I was determined to test out this Quik Shot. I gave it a prime with fresh 2 stroke mix......knowing that cylinders were dry....and spun it over with 12v wire disconnected from distributor so it wouldn't try to fire. The fuel filters were now full, as was the float bowl, but the accelerator pump plunger was not pumping gas as I expected. It was likely dried up......in fact it felt loose in the bore. Next, I gave it another prime with my squirt bottle, after hooking up the 12v to the electronic distributor. Then tried to start it. It ran like h##! But I was able to keep it running long enough my manually operating the choke at the carb. Then I shut down and started getting the calipers freed up, and working on things like putting in seat belts, seat, carpeting.....all the stuff it needed. 2 days later it is time to fire it up again. Still no pumping fuel from the accelerator pump so I primed again with mixed gas. Started and it ran better than before, but still missing on 2 cylinders. Once warmed up, I tried to drive it, but no accelerator pump action, so it kept trying to stall when I gave it more throttle. Okay, but the plugs started to hit and miss, but within 15 minutes it was hitting on all 8. Idle circuit was not right and it wouldn't idle so I set up the idle screw and set both low speed jets at 4 turns out.....a bit rich. Vacuum was running about 17 inches, should be 20. So I took it up the highway and after about 20 miles, a tire disintegrated, no spare AAA, and rollback home. Put 4 different tires on it and it sat another week. Then had a chance to use it on a firewood delivery and accelerator pump worked, idled pretty decent, and the dual glasspacks sounding sweet. By the time I got to the delivery....about 30 miles, the lady said, "WOW that truck runs nice, what year"? I really had to set down the idle because it was almost racing. When I backed it down to 600 rpm it sounded so sweet and smooth. My son and I unloaded the wood and went back home after stopping to slip on a new alternator belt.

So this is the truck, and that story is from September and October 2018. People glare at that truck in the gas station, store, stop lights. I never had to rebuild the carb, change filters again, replace fuel pump, or even spark plugs. It simply turns heads when idling. The performance on non oxy is remarkable. Ethanol is a poor source alternative to the octane boosters used in straight 100 percent 91 octane. You actually gain 3 to 4 percent power on non oxy over ethanol at 10 percent. I treasure my old outboards and other equipment, non oxy only......especially in my old diesels too. The new diesels are oxygenated too, so I use heating fuel with an additive. Shelf life is 20 times longer than this new crap that you get at the pump. Even the "off road" has got corn in it. It is also illegal to use ethanol in any airplane, including ultra lites.
Okay, gonna go cut some wood. Stay warm.