Noisy and shaky engine at idle but smooths out in forward or reverse

[stevebardocz]

I'm new to posting here, but I saw that there were a lot of experienced people here sharing ideas. I had our SX190 out on a Saturday taking a group of my daughters friends tubing. We parked it for cake and ice cream, and when I went to drive it on the lift, it started but then stalled as I tossed it in reverse and gave it some gas. It was close enough to the lift to pull it over, and so I did so, lifted it, and noticed the bilge pump was still going. I opened the engine compartment and it was almost to the top with water. So I let the pump run until it was empty and then cranked it a few times. It sounded like it really wanted to fire up but never turned over. I figured maybe a weak battery or wet electrical. So I brought the battery back (which had hot lead for attempting to start it) and left it to dry out.

A few days later I went out and hooked the battery back up. Everything was bone dry now since it was up on the lift. This time it did start, but then was a noisy struggling to stay running and then it stalled. I started it again and it ran, but it sounded like it was struggling. No check engine light though. If I give it gas while in the lift, it smooths out and sounds normal. This works in forward or reverse. I researched online and figured I should check for water in the engine. So I pulled out the spark plugs and cranked it over. No water came out. No water was visible. Oil looks normal and is still perfectly up to the fill line. Spark plugs had some rust, so I thought maybe one of the spart plugs was fouled out and it was struggling to run smoothly at low RPMs, so I ordered some of those, swapped them out thinking that would be the trick, but same results. I'm kind of at a loss at what the next thing to try. Inspecting the rods and lifters? I'm sure that's not easy, but I'm thinking that's my next step. I'm afraid to run it much in case it's actually at risk of damanging it. I thought about taking it out and opening it up some, but again, I don't want to do more damage.

I figured out where the water was coming in from. One of the helm drain plugs was completely missing. Not sure how this can both come unscrewed and then actually fall out. It has the plastic clip that holds it in, so I'm still perplexed about that. However, I replaced the entire drain assembly, and dipped it back into the water at the lift, and no more leaks.

Here is a video showing the motor running at idle and higher RPMs:

https://drive.google.com/file/d/19q_9Z9iKw3kSoN8HYD3HgmFUwy4CkQnu/view

Here is a folder that shows the SN and name plate of the motor, along with the spark plugs I removed, and the oil dip stick showing the oil to the full line with good, clean oil (at least as far as I can tell):

Google Drive: Sign-in

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drive.google.com

So I'm looking for some suggestions!

 

[RobbieO]

How about water in the intake?

 

[Cobra Jet Steering LLC]

Did you look in the oil dipstick to see if water was in the engine , I would remove the spark plugs and crank the engine. look for water spraying out of the plug holes also spray all the electrical connections with silicon spray I mean every one you can find. if you have water in the oil remove the oil and filter , change it and see how it works, there are many processes for removing all the water from the oil and I am sure many will chime in as well as checking your air cleaner element for oil and water .

 

[stevebardocz]

How about water in the intake?

How do I check that? I didn't look into that yet but will research it.

 

[stevebardocz]

Did you look in the oil dipstick to see if water was in the engine , I would remove the spark plugs and crank the engine. look for water spraying out of the plug holes also spray all the electrical connections with silicon spray I mean every one you can find. if you have water in the oil remove the oil and filter , change it and see how it works, there are many processes for removing all the water from the oil and I am sure many will chime in as well as checking your air cleaner element for oil and water .

Yeah, read my full post. I took out the spark plugs, replaced them, and cranked it over without the spark plugs in, as well as inspected for water, and it seemed dry, and the oil looks clean. I posted a picture of the dip stick with the oil so you can check out what it looks like, but it looked pretty good to me.

 

[Beachbummer]

Cobra Jet Steering LLC mentioned it, and worth checking: Does the Air filter look clean and dry?

 

[stevebardocz]

I'll check the air filter. Seems so obvious, but I didn't do it yet. You'd think that would dry out since it sat for a few days; plus, you'd think it would quickly burn off or blow out any moisure after starting it and running it with some RPMS.

 

[Cobra Jet Steering LLC]

ok remember spray all the electrical connections with silicon spray

 

[blacksapphirez]

check spark plugs... it could rust. after changing, it ran amazing.