Starboard engine idling rough

[Nikokrzynowek]

Backstory quick. I got this boat with the starboard engine completly seized up, never started it. Port engine ran just a ton of water in the oil. Rebuilt both engines got them in and running yesterday, just a quick start up they ran I shut them down. Went outside today to do a quick start up prior to taking them out to break in the engines and the port engine fired right up idled perfect no issues at all. Starboard engine tho fired right up then immediately stalled. Tried to crank it over quite a few times before it fired. Once it stared up it was idling really rough. Honestly sounded like the crank was going to fall out of the engine. Attached is a quick video of the engine running. I’m hoping someone on this form has had the same issue with their motor before and an easy fix. I’m leaning towards maybe a bad coil? And the engine is just misfiring or possibly injector. Any help would be appreciated. Thanks guy!

https://imgur.com/a/vqFOGKL

 

[Acard7]

Misfire is my guess. Kinda sounds like when I fog the intake on the MR1s when I winterize, Ofcourse they recover and run fine after it gets some air instead of fogging oil. How old is the fuel in the tank?…Even though port engine ran fine.. How old are the spark plugs? Oil level okay? Do you have YDS to plug in and test injectors and spark?

 

[Neutron]

Compression test to start

 

[Nikokrzynowek]

Both engines dont even have 2 minutes of them after full rebuild. I siphoned all of the fuel out of the tank and put fresh fuel. Plugs are brand new. Oil is brand new I put about 4.2quarts in. Bumped the stater with fuel pump fuse pulled to get oil into the engine prior to starting. I do not have YDS. I’ll pull plugs tomorrow and check to make sure there’s no fuel in the cylinders when cranking. Check the plugs and do a compression test. Is there any other way besides yds I can check the coils and fuel injectors to make sure their working properly?

 

[Nikokrzynowek]

Pulled all 4 plugs today and they all look brand new. No discoloration at all so I cannot tell if one plug isn’t firing. After I had the plugs out I was going to crank over the engine to see if I had alot of fuel in a cylinder. Nothing. Now I’ve got a no crank no start issue. Doesn’t even seem like there’s power going to the engine. Starboard RPM gauge is pegged at the 9k+. Nothing happens when I turn the key. Wtf is going on, started yesterday without any hesitation. I checked all of the fuses which were all good. Unplugged and plugged back in all electrical connectors. Still nothing

 

[anmut]

Is it possible one of your injectors is bad? Can you switch injectors from the cylinder with the fuel to the one that seems to be good, and try it again?

 

[Acard7]

Are your throttles in neutral? Maybe you bumped them.. Batteries charged or left on a tender? I assume you checked the connections at the battery? Cleanout hatch is closed? Do you have power to the blowers and all other switches?

 

[Nikokrzynowek]

No switches to on. Port engine fires right up. Double checked connections on clean out tray and batteries. Fully charged. Messed with the throttles and kill switch. Only 1 throttle body made sure it was in neutral. Only thing left is to jump the starer solenoid. As far as injectors. I’m not even sure what cylinder is the problem. On Amazon the injectors at 15$ I’m probably just going to buy 4 new ones and try that once I can get it to crank over

 

[David Martin]

Their are only 2 switches that kill starter for a no crank over..........neutral safety switch and the clean out hatch switch.

 

[Nikokrzynowek]

What about the starter solenoid? If that was bad I wouldn’t be getting power to the stator

 

[Acard7]

What about the starter solenoid? If that was bad I wouldn’t be getting power to the stator

Which you can rule this out by jumping it at the solenoid like you said above! Hope it works!

 

[Nikokrzynowek]

I’ll jump the solenoid today and let you guys know what happened. Fingers crossed that’s it because I already ordered, one for the $12 it couldn’t hurt, and should be here tomorrow. Besides that when putting the motor back together I noticed a little bit of corrosion on one wire for the rectifier regulator, and a little bit of corrosion in the fuse box. Going to clean everything, get all corrosion off the best I can. Put dialectic grease on all connectors. Swap injectors and coils to port engine and try to start it up. If the problem still persists on the starboard engine. I’ll try the injector test into a water bottle while cranking the engine over. Should be able to tell if the ecm is either sticking or not allowing fuel to flow. If the noise is still there could be an actual lower end issue. Only thing I noticed yesterday while messing around with it. The oil filter was not tight and looked like it leaked a bit of oil out maybe 1/4 - 1/2 quart. Hopefully even with a slight air leak the engine was able to get oil pressure

 

[Nikokrzynowek]

Update: swapped coils, plugs, and injectors from starboard engine to port and vise versa. I didn’t have a screw driver on me at the time to remove the solenoid and jump it, so I just started the port engine with starboard coils plugs and injectors. No issues. Smooth idle no noises. Which leads me to believe either a bad ecm either over / under fueling or an issue with the lower end maybe there was no oil pressure and the lights on the dash just don’t work.
I highly doubt some corroded electrical connectors would result in the noises I heard coming from the engine. But I’ll clean them up tomorrow when everything arrives

 

[Nikokrzynowek]

Anyone thing I could possibly have the timing off a tooth? Not sure what would happen if the timing was slightly off on a dual overhead cam engine. But the only thing that is steering me away from lower end knock / oil or bearing problems is the noise Doesn’t happen with every revolution of the crank

 

[Nikokrzynowek]

Solenoid was the no start issue. Jumped it engine cranked right over. Now I’m thinking for starters I’m going to pull the valve cover and inspect timing marks. These heads are rebuilt heads from SBT came complete with cams and everything. Because the knocking noise I’m hearing I believe is not occurring every revolution of the engine and only on the compression stroke, I’m going to check it he valve clearances and go from there.
Attached are some photos of the corrosion I found on the fuse box and fuel pump connector. Every spare fuse was shot, all super corroded inside the fuse. Maybe the previous owner replaced all of the active fuses because one of them is 10 amps and supposed to be 30 amps. Never the less it’s a problem I am going to address, but I don’t believe electrical is the engine noises I am hearing

 

[Acard7]

You should try pulling the pump when you do get it running again to make sure you’re not hearing any impeller racket noise too. I do feel you’re on the right track in finding your noise, but pulling the pump is easy and removes that small stress on start up too.

 

[Nikokrzynowek]

I’ll pull the pumps off tomorrow, but I highly doubt it’s the pumps. They were the first thing I rebuilt when I purchased the boat.m, because I was informed that was the only issue. Then come to find out one engine was seized and the other had water in the oil.
I’m just curious if anyone here started their boat with the timing slightly off. I feel as if it would be super had to start and would start bending valves.

 

[Acard7]

I have no experience starting a boat engine with bad timing, but my father and I once worked on a 92 eclipse 4 cyl and had to change a water pump which was in with the timing chain. We didn’t time it correctly but it would still turn over, just not fire up. After we timed it correctly it fired right up.

 

[Nikokrzynowek]

after I set the timing I spun the engine over a few times. I figured If the timing was off a tooth one of the valves would have kissed the piston and made it harder to turn over. So my timing is probably correct. So now I’m at maybe valve adjustment or possible ecm? I’ve listened to the start up video like 20 more times today. Seems like every time the engine makes that awful sound, the engine speed decreases, noise stops Rpms go back up to normal. Which makes me thing there is definitely an issue with either fuel or air. Lack of oil pressure and / or bad bearings could be a consistent knock and rpm wouldn’t fluctuate

 

[Acard7]

Swap your ECMs and that’ll rule that out