Evinrude stalling

[Mikeyman104]

I have a 1987 Evinrude 70hp (E70TLCUR) motor that is stalling out when I put it into gear. Under throttle she seems to do OK but at low idle, and with a load she stalls and sounds like she's running only on 2 cylinders. I put new OEM champion spark plugs in it, have run some seafoam thru it, changed the fuel filter, and gave the carbs a quick spray cleaning. At first was leaning towards it being a fuel/carb issue but now am thinking it might be electrical? Not sure though so if anyone has any thoughts or ideas of what to check out, I'd appreciate it.

 

Also wanted to note that I checked the plugs tonight and the top one had a lot of oil on it which makes me think this is the one that wasn't firing?

Edited May 22, 2023 by Mikeyman104
Edit to add note about checking plugs tonight

[MCF]

Power pack?

[nysrx01]

Unless you removed the carbs and took them all apart and soaked them don’t rule them out. 

[rolmops]

A few things to check:

do you have spark in every plug?

Are you using fresh fuel?

is the fuel coming through properly?

 I don’t know if it’s a VRO or a regular pump but make sure it’s a 40:1 mix.

To me it sounds like a fuel delivery problem. I would give the carburetors a proper cleaning.

[Frogger]

There’s a way to check your CDI electrical pack to see if that’s your issue. I think it’s on CDI electronics website if I remember right. Go through the basics as well with the fuel stuff. 

[HB2]

OMC outboards are  notorious vdor this 

 

Check for spark in all cylinders . 

 

Does it have 3 carbs ? 

 

Those power packs have a tendency to go . Along with the coils . 

 

If it runs better cool it probably electrical . 

 

 

[Shakemsam]

pump the ball as she starts to struggle. If that helps, it's fuel delivery. Most likely fuel pump.

[Frogger]

Shakesman just reminded me on the fuel pump, which is a great suggestion and possibility, not sure if that year or yours has the VRO pump with the fuel and oil. Be careful if you do not to mess with the oil side. If your ever in doubt of use mixed gas. If you already have a regular fuel pump and premix, use shakes and suggestion. 

[Mikeyman104]

Thanks all! Greatly appreciate the input!

 

It is a VRO unit and based on the oil in the top cylinder I was assuming it was working OK? (Pic of plug and head from last night)

 

New spark plugs so hoping that's not the issue. I actually ordered NGK plugs originally and that's when I first started noticing the issue and then I went back to OEM and no change. 

 

It does tend to run better when first starting in the morning. As day goes on usually becomes worse, which makes docking a bit of an adventure. 

 

Hadn't thought of the fuel pump, and really didn't want to do a carb rebuild but might end up going thay way. I'll check out the CDI electrical tests as well. Thanks all!

[lachsforelle]

Might want to pull apart that top carb and give it a good cleaning.  Pay attention to the reed valves...you might be flooding the cylinder.

 

 

[HB2]

Looks to me like the cylinder is not firing . 

 

Probably electrical is my guess . 

 

If it was carburetion or fuel delivery , it would run rough and smoke when you first changed the plug.  

 

Clean the plug good switch it with a good cylinder  and run it to see what happens . 

 

Check for spark 

[nysrx01]

Have you done a compression test on it yet.  

Edited May 22, 2023 by nysrx01

[rolmops]

Evinrude and NGK plugs do NOT work well together. You should always use Champion plugs. I know it does not sound logical, but it just is that way.

You can use either QL77JC4 or L77JC4

Edited May 22, 2023 by rolmops

[Mikeyman104]

Well, took apart the top carb to clean it best I could. Wasn't as bad as I was expecting getting it off so I'm sure I probably did something sketchy. Also, ones off it was nerve racking getting the small screw behind the drain plug out cause didn't have the best screw driver for it.

 

Only thing I noticed was this one gasket was pretty beat so put a new one on along with some other parts from a rebuild kit (ps. It's worrying how many extra pieces are included in those kits😆). 

 

Thanks again to all for the input on this! I also ordered a fuel pump rebuild kit, but that thing looked like a pain to get out. Might tackle that on a different night.

[HB2]

So Must be you have  spark on all cylinders if you tore the carbs apart . 

[LongLine]

you're not sparking properly on that top cylinder.  

[LongLine]

You can buy an inline spark tester at Harbor Freight for like $5 and test in your driveway.  (disconnect all plugs so it doesn't start) Tester should illuminate the same for all 3 plugs.  I had a similar condition on my "3 banger" (Less the VRO) a few years ago.  i.e top plug very wet after idling.  I found that I had a weak coil.   I replaced all 3 coils and performance improved dramatically.

[Mikeyman104]

Thanks all for the input! Much appreciated!

 

On Friday I ended up replacing the top cylinder ignition coil and power pack (found the power pack on Amazon warehouse so was a pretty good deal so figured why not replace it?). Run the motor in the driveway with the muffs on and seemed to run good. 

 

Took it out on Seneca today launching from Sampson. Made it about halfway across the lake and she just died. Was cruising at about 28mph and right down she went. No bang, or any odd noise like something breaking, but was able to get it going again after a bit and headed back toward Sampson only for her to die again. Couldn't get her running again and she was starting to turn over harder. Got back to the launch with the kicker and trolling motor so no real harm.

 

Got it home and pulled all plugs and didn't see anything noticeable. Tested compression on all cylinders and was at about 50psi for all 3 so something bad happened. She toast? 

[HB2]

That is typical of a bad coil . 

 

Runs good cool and after it heats up, it just dies . 

 

Then it cools and runs again . 

 

Check all coils for little cracks . 

 

Run in driveway after dark and look for arcing under the flywheel and sparkplug wires . 

[LongLine]

DOUBLE CHECK that compression!!!!!   That's very very low!  Older 3 bangers should be around 90 psi.  Any engine below 70 is going to run like sh[t.  You sure your gauge is working properly?   Hopefully the gauge you're using is a "screw-in" not a hand-held one. 

 

A bad coil can take out/deteriorate the power pack.  That's why I replaced all 3 coils. Coils can be expensive, but I bought mine from "Marineengine.com".

 

I'd suggest you buy a cheap multimeter (ohm meter) and test all 3 coils and the power pack before you put any more money into it.  Again, Harbour Freight has them cheap (No I don't work for HF....some of their stuff is worthless but their multimeter is more than enough for what you need)

 

You can google the specs and test procedures for your engine.  Those 3 bangers are almost indestructible and there's a lot of info and videos out there. 

 

As for hard to "turn over". pull all the plugs out and wrap a rope around the flywheel.  PULL!  (As you didn't hear any noises, it could be that you just wore your battery down trying to start it)  

 

 

 

 

[Mikeyman104]

Thanks all! My biggest worry right now is the low compression as I did use the screw in type compression tester and it was a brand new one right from the box so hopefully that isn't the issue. All plugs were pulled during the test but I can turn the flywheel with my hand so it's not overly difficult to turn. The starter struggles with it though but might be the battery? I did try 2 batteries to start it, but only 1 was a starting battery so might be the issue with the hard cranking. I had the starting battery on a charger for the last 2 days so I'll give this a quick look to see if she at least turns better. If she does, I'll give her another compression test and hope they are around 90psi. If so, then I'll replace all the coils.

 

I suppose worse case could be that the original stalling was tied to the fuel/oil pump on this thing and now the low compression is because they weren't getting oil and fried themselves? I obviously hope not, but does it kind of makes sense? 

 

Apologize for all the "if" "and" and "buts" about my testing and diagnosis here. First time diving into this motor so have been watching a lot of youtube and greatly appreciate all the insight above! Wife has been saying it might be time to take it somewhere for service. I'm not at that point yet, but am starting to lean that way  

 

[LongLine]

On my compression gauge there's a knurled ring up by the gauge to release pressure.  If that's not fully engaged, (closed) readings will be very misleading.  If still low, squirt a few drops of oil in the cylinder and test again.  (If still low, I'd go to an auto parts store & see if I could rent a gauge for a couple hours)

 

By hard to start, do you mean engine didn't want to turn over or do you mean it took a long time cranking to start?  I.e did you have to lay on the starter for a long time?  

 

A couple years ago, when I was out in Big-O and engine stalled on me.  Dumb me...I cranked & cranked..   After about 10 minutes of rest & panicked swearing, it started but died again.  I hobbled back to launch on kicker.  I was dumb cuz all that cranking really weakened my starter. Testing it and I had to replace it.  Starter shouldn't take more than 3 or 4 seconds at most to get it going.

 

Checked carbs & pump, recharged battery. Ran fine in driveway for about 5 minutes & I was happy.  Took to launch, it started fine but when I put it in gear & backing out, it died and wouldn't start.  After a lot of swearing, I asked for help in the forum on "Iboats.com. " (where I learned that there were a lot of 3 bangers still going strong.)  Anyways, a suggestion was to check the automatic choke solenoid.  Sure, as beans, the O-ring inside it was shot and the spring was fouled. This solenoid allows a lot of fuel into the engine, and it was flooding out.  (E-10 gas *!**!!)  Runs like a top now. 

 

Make sure you TEST, TEST, TEST & retest components before replacing them.  Parts can get very expensive!  

 

 

 

 

 

 

 

 

[Mikeyman104]

Update on the Ol girl: Took her to a shop and she had bad compression on the middle cylinder. 120/80/110 PSI on the cylinders from top to bottom. Could have done a rebuild or a motor swap, but figured it might just be time to move on from the ol leaky girl as I think the fixes/repairs were going to cost more than what it is was worth. Posted and sold on facebook so now in the market for a new to me boat. 

[LongLine]

Well that's a load off your mind...Compression difference is real bad...definitely a rebuild.  rings, head, etc. or someone bought for parts. (cuz they expensive)   Good luck with finding a new one.  Let us know what you get.