Starter turns, won't start, and a whole range of other questions ...

[Hai Nhi]

Good morning everyone.

I did some search but I'd like to run by CSR to get more/better advices, please

First of, my engines are 2001, Mercruiser 4.3L EFI V6, about ~460 hrs each. I bought the boat about 2 years ago, but only put about less than 10 hrs (60-70% salt). I'm not sure (forgot) if the previous owner did any service/tune up. The only thing I did was changing the outdrive oil begin of last season.

Current conditions:
- Port engine cranks but won't start 2 weeks ago.
- I checked and cleaned the rust off the cap & rotor metal contacts. Still no start. Pulled one of the spark plugs and I think it looks ok but I could be wrong
- I then also noticed the exhaust bellow was torn in half at bottom connection (port side). Probably because of outdrive left high up. Yeah, I know now.
- Exhaust manifolds and elbows got rusted fairly bad on the outside at connections on ONE side in EACH engine. The other side got just a little bit rusted only . I noticed that they are both either original/oem (with mercruiser name imprinted on them).
- Bottom of water heater is rusted, though water heater seems to be working still.
- Bottom of a couple of other spots are rusted: starboard power trim bracket, a couple of engine mounts, etc...
- Trailer button only operates port trim
- Starboard power trim only goes down, not up (just recently) ==> new trim sender & limiter installed last season
- Port power trim ==> rebuilt last season. but trim pump doesn't auto stop when reach max up or max down like the starboard side. It keeps running if pressed.

My plan of actions:
- New tune up kits bought (cap & rotor & spark plugs). Plan to tune up both engine at the same time to get a starting point.
- New bellow kits (complete transom bellows kit with gimbal bearing and all) bought. Plan to change them all on both
- New seal kit & water pump repair kit for outdrives bought with oil seals. Same thing: plan to change on both
- Also bought 2 trim pump solenoids just in case if I troubleshoot to be the cause

My questions:
- Please advice plan of action (steps/procedure) to troubleshoot the no start, if after tune-up still a no go.
- With all the rust places mentioned, would an in-place clean up / touch up paint advisable? Or pull them all out to properly clean them? I know pulling the machine is no-joke job. But if that's what it takes, I can do it - no matter what it takes. Can the water heater be cleaned/replaced without the machine being pulled? Starboard power pump too, It's all the way to the back and it's next to impossible to service/troubleshoot/clean it without removing the head system vacuum generator.
- Should I change the oil & filter after I fix the starting problem?
- What about the exhaust manifolds and risers? These are like $700-$800, or more a pop. I'm running in salt water most of the time. So I was thinking about installing the complete closed cooling system. But that's also $1000/ea. Haha. Now I understand the saying: double engine, double the fun, and double the running cost too. I also curious about if stainless steel exhaust parts are recommended. I saw SS riser but only see aluminum manifold. What would be the best combination as far as exhaust & cooling goes for salt water running?
- Anything else I should look into doing/repairing/changing while I'm at it?

I plan to do them all by myself. So I need lots of help & encouragement. Hehehe.

Thanks in advance for helping.

 

[dcpringle]

If still no start;

After you change the plugs, wires, cap and rotor, check to see if you have spark. Pull a plug wire and hold it about a half inch way from the exhaust manifold and see if you have a spark, or get a spark tester from the parts store and install and look for the light. If you have spark but still wont start, then you have to look at the fuel system. Start by seeing if the fuel pump is running when you turn the key. Stupid question but did you open the fuel shutoffs? Hope this helps...

 

[wish2fish]

Question for mechanics: Can you just spray a little ether into the throttle body to determine if it is a fuel issue before you go exploring all the possible no fuel causes?

 

[Bucit]

When you push the starter switches one click you should hear the fuel pumps kick on for a few seconds as well. If you removed the cap and rotor are you sure they were put back in the exact same spot? Timing could be off?

 

[kkalsch]

Is the battery fully charged and is it in good condition? On that engine... if it does not turn over fast enough it will not start-

 

[Hai Nhi]

Thanks for the quick replies.

- batteries show very healthy. I'm still plugged in at home on the trailer. Starter cranks pretty strong I think. But I will double check that too. Maybe switch to the other battery (starboard side starts right away, so that battery is for sure good)
- cap is back correctly. But the rotor is pretty tough to take off. I tried yanking it out by hand but couldn't. Also, the gap in the sensor assembly where the sensor wheel passes through has some rust on it. I didn't clean that up last time yet.
- When I first push the button (first push, before the start push), the fuel pump starts. I can hear a very healthy noise, just as loud as the starboard side. Right outside the fuel tank, after the valve seems to be another fuel pump (pls see attached photos), (other than the fuel pump & fuel cooler, which is mounted port side below the engine). What's that used for? How do we check if any of these gone bad?
- Last time I tried to take the flame arrestor out, spray some starting fluid down there but didn't know what to look for.
- Throttle body assembly has rust.
- I'm gonna go get the spark tester as well, to see if we have sparks.

All my parts should be here Friday. I think I'm gonna take Saturday afternoon & Sunday to work/troubleshoot it. So more ideas/tips/advices pls . If anything I can try before replacing stuffs, I can do it tomorrow afternoon.

I tried to attach the pictures but can't.

 

[Sal A]

Remove the flame arrestor spray some starting fluid down the throttle body if it fires check the cool fuel module. I believe cool fuel system has 2 fuel pumps the one in the cool fuel module boost fuel pressure. Low fuel pressure will cause the injectors not to spray . ( not to much starter fluid it helps to have someone crank while you spray )

 

[kkalsch]

When you mention the rotor was hard to get off -I had the same problem with my 2000 240 ...check your serial #

 

[Hai Nhi]

Remove the flame arrestor spray some starting fluid down the throttle body if it fires check the cool fuel module. I believe cool fuel system has 2 fuel pumps the one in the cool fuel module boost fuel pressure. Low fuel pressure will cause the injectors not to spray . ( not to much starter fluid it helps to have someone crank while you spray )

Thanks Sal. I'll try that again

 

[Hai Nhi]

Great post kkalsch.

My sn is om096744, but that's good info still.

I was thinking of taking the good one on stbd side to replace and try to isolate the problem, if it comes to that. One notice though, these two are not the same (the sensors). So maybe one of them was replaced by an alternative in the past or something. I'll double check to make sure.

 

[Sal A]

Good luck let us know what you find

 

[Xplicitlnck]

Ok here we go. Start with the free fixes1. Check the kill switch. Little red switch about waste high on the starboard side standing next to the wheel. (On most boats atleast)2 check your fuel valves are open3. Make sure you have spark. There are many ways to do this. I usually carry an extra plug so all I have to do is disconnect a plug wire connect it to the plug and hold it to something metal on the engine while having somebody crank the motor. No spark? Your next step is make sure the wires are good. Just because they look good does not mean they are good. Next pop cap and rotor off. Connections clean and making contact? Next the coil. In my experience is usually the culprit. Swap it with the running motor if the problem folllows the coil then you've figured it out. If it's not the coil start tracing wires (I've also heard of no starts due to engine harness being loose at the computer. Now you had spark at the initial plug testtime to check fuel. Do you hear the hum of the pump when u turn your key one click? Grab a fuel pressure gauge from your local hardware store and check the pressure and c if it's to spec to YOUR motor. How old is your gas and did the ethanol take over? Pull fuel filters poor in glass jar and observe. Now if u have cool fueldo your research on them. II've never had them but heard horror stories. There very expensive and known to fail. They are painted on the inside and the fuel eats the paint and clogs the filter if my memory serves me right. If all this failsb.o.a.t. call the mechanic

 

[Xplicitlnck]

Exhaust bellows. Now im pretty sure there service life is 4 years? If there torn I would pull both dRives and replace ALL the bellows. I think there is exhaust, shaft, and shift bellow. Also check the gimball bearings. While u have the drives down this is the tune to figure out why the hydros are not working. It could be the trim limit and position sensors. Rule them out or change them while the leg is off. In order to change you will have to remove more of the transom assembly. Your manifolds and risersDo you know when they were last changed? If the outside is rusted imagine what the inside looks like. If u have no idea when they were last changed I would at minimum pull them and inspect. There service life seems to b about 5 years. My opinion is to stick with what material The factory put on and not start introducing dissimilar metals to your block. (Dint use stainless or aluminum) again personal preference. Sine people may say different.The water heater I would leave till last if it's still working.as for the trim bracket they sell a stainless steel one on eBay fairly inexpensive swap it outas for swapping over to fresh water cooling. If your motors have been ran in salt water already there's little to no advantage to swapping over now. Once the engines are introduced to salt is very hard to get it out. Wait till you next repower and add it then. Changing oil will never hurt you

 

[Hai Nhi]

Morning Xplicitlnck.

Thanks much for the detail posts.

I might have some free time today afternoon - if not, tomorrow - to work on it and report back.

 

[BryanOnTheBay]

Exhaust bellows. Now im pretty sure there service life is 4 years? If there torn I would pull both dRives and replace ALL the bellows. I think there is exhaust, shaft, and shift bellow. Also check the gimball bearings. While u have the drives down this is the tune to figure out why the hydros are not working. It could be the trim limit and position sensors. Rule them out or change them while the leg is off. In order to change you will have to remove more of the transom assembly. Your manifolds and risersDo you know when they were last changed? If the outside is rusted imagine what the inside looks like. If u have no idea when they were last changed I would at minimum pull them and inspect. There service life seems to b about 5 years. My opinion is to stick with what material The factory put on and not start introducing dissimilar metals to your block. (Dint use stainless or aluminum) again personal preference. Sine people may say different.The water heater I would leave till last if it's still working.as for the trim bracket they sell a stainless steel one on eBay fairly inexpensive swap it outas for swapping over to fresh water cooling. If your motors have been ran in salt water already there's little to no advantage to swapping over now. Once the engines are introduced to salt is very hard to get it out. Wait till you next repower and add it then. Changing oil will never hurt you

If you have the drive off replacing the bellows, you might as well change out the sensor. You can't do the job properly with the outdrive on. I wish I had done that last year when I had my drive off getting it checked and new bellows put on. It is a simple, and pretty inexpensive job to do with the drive off. If they are not bad, they soon will be. From now on, every time the drive comes off, they are being replaced. They fail too often.

Bryan

 

[Hai Nhi]

Yeah I hear you Bryan. I just replaced the pair on stbd side last season. Will replace them all this time. I assume you're talking about the trim switches - sender & limit, right?

Nhi.

 

[themikehyde]

Sorry, I am totally lost on this thread. Did you get the engine started?
Mike

 

[BryanOnTheBay]

Yeah I hear you Bryan. I just replaced the pair on stbd side last season. Will replace them all this time. I assume you're talking about the trim switches - sender & limit, right?

Nhi.

Yup. Trim sensor and limit switch No clue why I said left out the switch. . . other than I was typing it while my kids were screaming during tae kwon do.

Bryan

 

[BryanOnTheBay]

I think that the free time this afternoon didn't happen for him...

 

[Hai Nhi]

Haha. That's right. I meant to go home early but got stuck in traffic for 30 mins going back on San mateo bridge. Then decided to head to a customer to seal the room addition deal. Customer (& I) talked a little bit too much side track. Which killed another hour and a half. So by the time I got back home it's 6.

I got my order of the bellow kits and tune up kits delivered though. I plan to wake up early in the morning to test out a couple of things. Maybe stay home the whole morning if I get some progress. . Will see.

On the trim sender & limit kits, I got the Sierra ones. Not sure how durable they are but they got pretty good reviews on Amazon.

Oh, how often should oil & filters be changed?