‘99 Johnson 115 running on 2 cylinders?

[QuickPuppy]

I have a ‘99 J115PLEEM that I’ve had no luck with getting to run properly. I’ve rebuilt the carbs several times due to fuel dumping out of the front when the primer bulb is pumped up. It ended up that the seat was stripped on one of them and there was a crack in another. I replaced the those two carb bodies and I finally seem to have fixed the leak issues.

I found that the low speed needles were set at 11-12 turns out instead of the 4.5 turns that the manual calls for. I reset those.

The fuel tank has been cleaned out, the fuel lines replaced (except for the ones in the engine itself), new spark plugs, good spark everywhere, reed valves look good, compression is good.

It will start right up and idle but it seems to only be running on two cylinders (port side). If I pull the spark plug leads on the starboard side, there is little to no change in how it is running. If I do the same on the starboard side, it stalls.

If I cover individual carb bores for a second or two while it’s running, the following occurs;

Starboard carb bores fill with fuel, not much change in how it runs while covered but it will start to rev more as all the excess fuel is sucked in when uncovered again.

Port side carb carb bores fill with fuel, begins to stall while covered. Smokes and backfires with all the extra fuel when open again.

It sure seems like a fuel delivery issue, but why is it only one side of the engine that seems to be affected?

 

[jakedaawg]

Compression is what? Does spark jump a 7/16" gap on an open air gap tester? Are you running in the lake when doing your cylinder drop test? That motor would be difficult to tune for many if running on muffs or in a barrel.

 

[racerone]

How long have you owned it ?-----Any chance that orang wires FROM the powerpack are not going to the right place on the coil ?

 

[Chris1956]

You need to establish if you have spark on the starboard side. If you do have spark, examine the spark plugs for color and wetness.

 

[QuickPuppy]

Last time I checked, the compression was 137-135-143-141.

Plugs are gapped to spec.

There is a strong spark that jumps from the plug wires to each of the cylinders when I pull them while it’s running. I’d say that It jumps at least a 1/2 inch.

I’ve been testing the boat in my pond, not on muffs or a barrel.

I’ve owned it for the past couple of years but it has only been on the water a couple of times as I spent a ton of time replacing the deck. See here for the rebuild thread... the last pages have more info on the engine issues.

https://forums.iboats.com/forum/boa...-99-larson-186-sei-ski-n-fish-re-deck-project

The first time I had it out after rebuilding the carburetors it seemed to run great. It ran about 41 miles an hour. That was the only time it ran well. Since then, it struggled to get to 30mph and I’ve been having these other issues as listed above.

If I give it full throttle, it misses and stumbles and then catches like the other cylinders eventually start to fire, but it still seems very low on power to me.

 

[QuickPuppy]

Anyone?

Does this engine have two fuel pumps? (A VRO pump and another) I got a “fuel pump” rebuild kit but I can’t seem to find where the actual part is on the motor... it all appears to be the VRO pump that looks different that the kit that I have.

 

[racerone]

There is a wee " vapour extraction " pump.-----Part # of the kit you got ?

 

[QuickPuppy]

It’s a sierra 18–7800 fuel pump kit. Replaces OMC 438616.

 

[racerone]

Well ,----that fuel pump kit is not " standard " for a 99 model V-4.-----Where / how did you order it.-----On line / from a BRP dealer or something else.----Not the kit for the vapor pump either.----Is the VRO in service , yes, no or not sure ?------Have yiou checked oil level in the oil tank?-----Checked filter in oil tank ?----Checked for water in fuel tank and oil tank ?------Water pump checked ?-----Overheat warning alarm checked ?

 

[QuickPuppy]

The rebuild kit is what the local shop gave me.

VRO is in service and appears to be working... as far as oiling goes.

Both fuel and oil tanks were removed, cleaned, lines replaced. Check valve on fuel tank is new. Added a fuel/water separator. Full of fresh fuel and new oil.

Water pump is new.

I attempted to test the overheat alarm but the instructions on how to do it are in a supplemental manual that I don’t have, so I do not know if it works or not.

Once again, it does seem to be running on one side of the engine (port side), appears to have spark everywhere.

 

[lmuss53]

Check what racerone said, plug wires or wires to coils sound like they're crossed.

I had one here that a guy built and got the wires to the coils backwards. Instead of rewiring it he just crossed the plug wires, and it ran fine. He sold the engine to a guy from my town. The new owner let his son borrow it, he saw the crossed wires and "fixed" them, and then the boat would not run. It started even idled but popped and sputtered when he tried to get it to push the boat. It took me a couple hours to figure out what was going on, but we got it fixed.

 

[racerone]

Sad when the local shop does not know what pump is used on a 1999 model !!

 

[QuickPuppy]

I’ll double check the plug wires tonight… It does sound like it could be possible.

 

[QuickPuppy]

The repair manual seems to show something very similar to the rebuild kit I got.

 

[racerone]

But that may be for the 88 HP model crossflow ( your model # is a looper ) that 88 HP was NOT marketed in 1999 year !!-----On the inside of the front of your manual cover is your motor model # printed ?--------Post the front page of this manual what motor model years is this manual for ?.----Does it cover your model year.-----This is all really simple to me and should be straight forward for your dealer too !.

 

[flyingscott]

The looper motors like yours were never marketed without a VRO pump. Like Racer said that pump is for a crossflow model not yours.

 

[QuickPuppy]

 

[QuickPuppy]

These look correct to me...

 

[flyingscott]

What looks correct?

 

[QuickPuppy]

Plug wires going to the proper plugs.