Starboard engine won't start

[SprockJohnson]

Hi all,

New to this forum but not new to jet boating. I have a 2006 Yamaha AR210 I bought new in 2006 and although I haven't had many problems over the years this one is turning out to not be simple to diagnose. I last ran the boat a week and a half ago and it ran great and had a thorough post run rinse out from the saltwater. Yesterday I went to put the boat in the water and the starboard engine would not start. The starter was turning the engine over, although slower than the port side, but it would not start. Here is what I have already done to troubleshoot-

1. The tank is full of new ethanol free fuel
2. The shifter/ throttle is in neutral and I have also swapped the connectors for the neutral switches back and forth between the two sides.
3. The kill switch has the lanyard attached and I have swapped the connectors back and forth between the two engine sides.
4. The cleanout hatch switches had already been bypasses a year ago but I inspected the connectors and splices to verify there is no corrosion.
5. All spark plugs were removed, inspected, and checked for spark and they all appear fine. They were just replaced a couple months ago and only have a few hours on them.
6. All battery terminals and cables for both batteries (one was added aftermarket) and the aftermarket battery selector switch were checked, removed, brushed with a wire brush, and reattached to the batteries and switch.
7. Swapped the connectors for the ignition switches to see if the other switch would start the engines. Port side still starts but same problem persists with the starboard side.
8. Both batteries are fully charged, voltages were checked and reading 12.6-12.5v.
9. Removed deck hatch and removed starboard side fuel pump unit, checked fuel filter screen which was clear, and re-installed. Fuel line was pressurized before removing and pressurized again after installation.
10. fuel is observed misting out of head when spark plugs removed.
11. Throttle body checked and servo functioning.
12. Attempted to start with starting fluid but no detonation.
13. Checked all fuses on starboard ignition module.
14. Checked voltage at positive starter cable and it read approximately 10.6v and engine rpm while cranking was somewhere between 350-400rpm.


Anybody have any ideas? I'm thinking my next step will be to swap the starters to see if that is the problem.

 

[212s]

Sounds like no spark - check coils?

 

[SprockJohnson]

It is getting spark on all four plugs. I checked them all out of the cylinders while cranking the engine over and all appeared to have plenty of spark.

 

[212s]

It is getting spark on all four plugs. I checked them all out of the cylinders while cranking the engine over and all appeared to have plenty of spark.

So you have crank, spark, but no chamber ignition?
That's a combustion chamber issue I think...fuel problem perhaps?
Google the combustion cycle and see if you can narrow it down...there's a lot of electronics in there too.

 

[SprockJohnson]

Thanks. Will do.

 

[zipper]

10.6V while cranking is too low. What is each resting battery voltage? After being disconnected from the charger for a couple hours. Check to make sure all battery cables are tight again. How old are the batteries?

 

[SprockJohnson]

So, a little update- It would appear it is not the starter as I first jumped the starter directly from the positive post on the starter to the positive terminal on the battery. Same slow rpm from the starter and no start. I swapped the port engine starter with the suspected bad starter, even though I was now doubting it was actually bad, and the port engine starter behaved the same on the starboard engine. Slow rpms (300-400ish) and no start. The suspected bad starter worked perfectly on the port engine and it started right up as usual. I swapped cam position sensors just in case and no dice. Still replicating the same slow rpm's. Spoke to a friend who owns a boat repair business and he said it could be the jet drive causing binding so I removed it and alas, no change in the phenomenon and zero detonation. I tested compression on the first two cylinders and zero psi. I checked the compression tester on the other engine #1 cylinder and it read 170psi after the engine started. My "boat repair business" friend recommended I remove the valve cover and see if the cam shafts are rotating with the crankshaft as it is looking more and more like internal component failure. I'll try this tomorrow as I have the day off. Anybody have any other guesses or advice?

 

[Gym]

Maybe the timing chain broke or you have a stuck valve. Do you use ring free or any fuel additives that remove carbon?

 

[SprockJohnson]

Only additive I have used somewhat recently was sea foam. Here's what I did yesterday-

Valve cover partially removed and I was able to observe the cams and timing chain all intact and rotating like they should. Timing chain tension appeared fine and nothing visually jumps out as broken or damaged. We used a lighted bore scope and checked the inside of all the cylinders with the plugs removed and 1-3 had heavy carbon buildup and #4 appeared noticeably cleaner. Going to be removing the valve covers completely as well as the intakes to look at the intake valves and to see if they are sticking and if so then to shoot them with solvent. I haven't checked the valve lashing but will do so with the valve cover off and might as well check the other engine too.

If it is indeed sticking valves, what are the chances that 3 out of the 4 cylinders would stick all at once?

 

[SprockJohnson]

I removed the head from the engine and as it turns out all four cylinders had stuck valves. Removed all valves and will be cleaning the buildup on the stems of the valves and the ports on the head. Nothing appears damaged, but there is some serious amounts of buildup on both the valves and the head. Dirty fuel? Bad detonation? I got the impression that this wasn't an overnight amount of crud which had built up on the head and the valves.

 

[WREKS]

Is it possible engine was overfilled with oil? Is the bottom of the airbox dry? What is the condition of the filter in the bottom of the air box that connects to the oil separator hose? Is this the same problem that 'Need help troubleshooting engine starting problem' is referring to?

 

[SprockJohnson]

Airbox is dry and air filter appeared fine. Yes, I put the same post in "Need help troubleshooting engine starting problem" to get more input for this.

 

[WREKS]

Airbox is dry and air filter appeared fine. Yes, I put the same post in "Need help troubleshooting engine starting problem" to get more input for this.

@SprockJohnson Just so we our on same page, the filter I am referring to is at the the bottom of the airbox under the throttle bodies. I would call it an oil breather filter.

 

[SprockJohnson]

Ah, I think the confusion on my part is because that is not the type of part (the large square box on top of the MR1 engines) which I have on my FRT1100CE engines. I have the remote cylindrical air box on the side of the engine compartment.

 

[WREKS]

Ah, I think the confusion on my part is because that is not the type of part (the large square box on top of the MR1 engines) which I have on my FRT1100CE engines. I have the remote cylindrical air box on the side of the engine compartment.

Ok. If you haven't already, I would check the filter where your breather hose plugs in to see if it has any oil in it. I think it is at the encircled location.

 

[3 green tornados]

I have no advice because I am to new to these engines. I am curious to know how many hours are on the engines. Mind sharing?

 

[SprockJohnson]

I don’t know how many hours since I haven’t hooked it up to the YDS software yet, but it’s probably a lot of hours. That’s on the to do list...

 

[Jimmers]

I removed the head from the engine and as it turns out all four cylinders had stuck valves. Removed all valves and will be cleaning the buildup on the stems of the valves and the ports on the head. Nothing appears damaged, but there is some serious amounts of buildup on both the valves and the head. Dirty fuel? Bad detonation? I got the impression that this wasn't an overnight amount of crud which had built up on the head and the valves.

View attachment 124795

I am constantly amazed at the mechanical knowledge some of you guys have! A year ago the service engine light went on in my wife’s 20 year old car. We took it in and it was an easy fix( still expensive). But the shop said that they had an oil additive that might quite and clean the tappets or rocker arms. It did make a loud clickety sound at idle. It was a several hundred dollar oil change with the two additives but it did reduce the clickety sounds dramatically. I have purchased the additives and going to use them the next time I change the oil in that car. It’s a BG engine performance restoration additive, One can for 10 minutes running in an already warmed up engine, one can as an additive to stay in with the new oil and a can for gas treatment.

 

[SprockJohnson]

Since you revived the thread I'll give an update. As it turned out, the rings on two of the cylinders were stuck/ compressed/ worn to the point that I was getting little to no compression on those and this was causing extreme amounts of oily blow-by. I suspect this is what contributed to or caused the dirty and stuck valves. I ended up rebuilding the entire engine and it is finally, after a year or so, running like a champ.

Everything said and done, parts and some tools I didn't already have, this was about a $2000 job. I bought the YDS software and interface but have not had any luck getting it to connect so I still don't know how many hours I have on each engine. My boat spent the first half of its life in freshwater lakes but the last 7 years have been exclusively saltwater in the Florida Gulf with just simple freshwater flushes at the end of the day without Salt-Away. I don't know if the saltwater/ salt air was a contributing factor to the ring wear but I figured I would mention it since during the teardown of the engine I observed only little to moderate corrosion buildup in the cooling lines and cooling channels of the head.

All in all, I'm impressed with the Yamaha engine. It sucks to work on, however, since the disassembly and assembly torque specs call for not just ft-lbs or in-lbs but also specific angles of tightening after the initial torque. I was initially very reluctant to pull the engine from the boat to work on but in the future would have no qualms about doing that since it really wasn't a big deal. The engine is light enough for two adults to lift out, attach to a chain, and then lower down to ground level. The bearings were a pain to identify as they are coded by color from Yamaha and plastigauge was necessary to figure out tolerances and then translate those to the Yamaha color system.

I recommend to anybody doing a rebuild like this to remember that the remote oil reservoir is basically just extra overflow and cooling. I mention this because when you fill it with oil and then start the engine, the oil from the reservoir gets pumped down into the sump and there's not enough to fill the reservoir up again, which will in turn then cause the low oil light to trigger and will cause the engine to run hotter than it should. Easy fix. Just re-check the engine after a few minutes of operation and re-fill the reservoir. Hope this helps somebody else in the future.