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BTV
06-07-2012, 12:23 AM
My 09 X15 with MCX has become harder to start. I have to crank it longer to get it to start. Once it starts it runs perfect. Anyone have any ideas what the problem might be? Thanks in advance for any help.

sand2snow22
06-07-2012, 12:37 AM
How many hours? Ever change your cap/rotor/plugs? Sounds more like a fuel problem tho? How much gas is in the tank?

petermegan
06-07-2012, 04:09 AM
There must be a drainback valve for fuel somewhere, anybody able to help with that. Just a possibility?

mikeg205
06-07-2012, 07:36 AM
09? what's pressure in the fuel rail? all coil connections clean and tight?

JimN
06-07-2012, 08:17 AM
My 09 X15 with MCX has become harder to start. I have to crank it longer to get it to start. Once it starts it runs perfect. Anyone have any ideas what the problem might be? Thanks in advance for any help.

Ideas? Not many without knowing more about the boat's service history. Anything done to it, recently?

Next time youp try to start it, turn the key to ON, but wait about 5 seconds before cranking. If it fires up, it's probably just dropping pressure faster than it did before. If not, I would check the fuel pressure while cranking.

Otherwise, it may still be under warranty- take it in.

snork
06-07-2012, 08:45 AM
Hard to start when engine is hot but sitting for 15 min or more?

ntidsl
06-07-2012, 09:17 AM
I had the same thing last year but very minimal. I had changed the fuel pump and assumed it was just that i didnt tighten one of the hoses completely. But this spring I did a full tune up including new rotor, cap and plugs and double checked all my gaps...and I haven't has the issue this year. Same engine but mines an 05 and the cap and rotor had never been changed. My engine sparkles and the boat is always dry...I was AMAZED at the corosion under the cap.

BTV
06-07-2012, 09:38 AM
Thanks for the replies.

The boat has 250 hours. Have not changed cap, rotor, plugs or tuned it up. I don't let the gas get much below half before refilling. I just changed the oil, but have noticed the problem getting worse since the start of this season. Sometimes it fires right up and sometimes it cranks up to 5 seconds to start. The nearest dealer is 350 miles away so I would really like to solve this myself. What do I need to check fuel pressure?

Again thanks for your help.

meg
06-07-2012, 10:39 AM
My MCX did the exact same thing for a couple of years and ended up being a fuel pump issue. It was probably the fuel filter which I didn't change until I killed the fuel pump!!!!!

sand2snow22
06-07-2012, 11:28 AM
After checking fuel pressure, you should do cap, rotor, plugs and fuel filter to keep up with the regular maintenance.

JimN
06-07-2012, 08:31 PM
Thanks for the replies.

The boat has 250 hours. Have not changed cap, rotor, plugs or tuned it up. I don't let the gas get much below half before refilling. I just changed the oil, but have noticed the problem getting worse since the start of this season. Sometimes it fires right up and sometimes it cranks up to 5 seconds to start. The nearest dealer is 350 miles away so I would really like to solve this myself. What do I need to check fuel pressure?

Again thanks for your help.

If you have an AutoZone store near you, they loan tools. Other auto parts stores do, too. I don't know who's near you but if you're 350 miles from a dealer, I would have to guess that you're in West Tx. OTOH, if you know a GM mechanic, they know how to diagnose anything on this engine. If it's on the trailer, you can run it all day long if you give it a steady supply of fresh water to cool it. A watering trough, plastic barrel, garbage can or any other large container would work for this, if you have one. You would need a piece of 1-1/4" hose that won't collapse and a hose clamp. Dip it in the water, fill the container & keep filling it as you run the engine.

willyt
06-08-2012, 08:52 AM
My MCX seems a little hard to start too, I've put it on combine batteries when trying to start but that doesn't affect the problem at all...
Mines not a 5 second crank, more like 2-3. Unfortunately I'm heading to Norris lake on Tuesday so I'll have to take care of this afterwards

JimN
06-08-2012, 08:57 AM
My MCX seems a little hard to start too, I've put it on combine batteries when trying to start but that doesn't affect the problem at all...
Mines not a 5 second crank, more like 2-3. Unfortunately I'm heading to Norris lake on Tuesday so I'll have to take care of this afterwards

2-3 seconds is NOT a long time to crank- how long do you crank your car before it starts? Remember- your car and your boat have different fuel systems- the car's tank isn't vented and your boat's isn't pressurized. If it cranks slowly, that's one problem but if it cranks at normal speed (somewhat over 300 RPM), you don't need to combine the batteries.

Before trying to fix anything, do some tests. Guessing isn't a good way to find problems.

willyt
06-08-2012, 09:18 AM
yea... i know guessing isnt a good way of solving problems, i killed my house battery a couple times already this year from listening to music when stopped so my theory was the CCAs weren't as high as they needed to be.
my tahoe starts in about 3/4 a second, and my old MCX seemed to start in about that amount of time as well. I've got about 360 hours on my boat (only 40 of them are mine) so i might do cap, rotor, fuel filter, tranny fluid, etc to make sure i'm up to date

TN X-45
06-08-2012, 09:23 AM
If you are doing fuel filter, you might as well do the fuel pump. ~350 hours seems like the magic number for fuel pump failure. I just replaced mine!!

JimN
06-08-2012, 09:47 AM
yea... i know guessing isnt a good way of solving problems, i killed my house battery a couple times already this year from listening to music when stopped so my theory was the CCAs weren't as high as they needed to be.
my tahoe starts in about 3/4 a second, and my old MCX seemed to start in about that amount of time as well. I've got about 360 hours on my boat (only 40 of them are mine) so i might do cap, rotor, fuel filter, tranny fluid, etc to make sure i'm up to date

Again, test. If it has 360 hours on the things you listed, I would probably replace them, although the cap and rotor are probably OK (check them out first). Transmission fluid should be changed annually. How clean is the flame arrestor?

sand2snow22
06-08-2012, 03:45 PM
You should have seen me try to start a 2010 247 LSV with the 8.1 yesterday. Took forever to start, cranking forever, nothing, have to give it full throttle? Almost like a carb boat????

Thrall
06-08-2012, 03:48 PM
Longer crank times to fire (if good battery power) is a typical symptom of the fuel pump going out. That was the symptom on my buddys MCX with about 300hrs on it before the fp died.
I dont advocate throwing parts at a problem either, but at 250+ hrs, a new fp is more of a maint item on these boats.
You need a fuel pressure guage with a Schrader valve connection on it to test.
I'd probably just get a new pump and replace it now anyway before it does go out.
Read up on fuel pumps on here. There's an economical way to do it if you want to do it yourself. Les than $100 for a new pump only vs $4-500 for the assembly from MC.

onewheat
06-08-2012, 06:36 PM
Thanks for the replies.

The boat has 250 hours. Have not changed cap, rotor, plugs or tuned it up. I don't let the gas get much below half before refilling. I just changed the oil, but have noticed the problem getting worse since the start of this season. Sometimes it fires right up and sometimes it cranks up to 5 seconds to start. The nearest dealer is 350 miles away so I would really like to solve this myself. What do I need to check fuel pressure?

Again thanks for your help.

There should be no cap or rotor on an '09. It should be coil on plug. They do recommend plugs at 300 hours though, so you are getting close. You might try that - easy to do, inexpensive and almost due anyway. Have you cleaned and oiled the air filter recently? Too long ago and it may be dirty - just done and it may have too much oil - both restrict air flow. I'd start there and see what's what.

JimN
06-08-2012, 06:58 PM
You should have seen me try to start a 2010 247 LSV with the 8.1 yesterday. Took forever to start, cranking forever, nothing, have to give it full throttle? Almost like a carb boat????

Did you check fuel pressure? That's the first thing to do. If you cranked it for a long time, sniff the oil- if it smells like gas, change it.

Next thing to try, if you don't have a fuel pressure gauge, turn the key to ON but don't crank it. After about 5 seconds, turn it off and wait for about 5 seconds. Turn the key on and wait 5 seconds before cranking. If it fires up, I would definitely check the pressure. Take a fuel sample at the same time. If it looks good, it may just need a pump and/or filter.

snork
06-08-2012, 07:44 PM
There should be no cap or rotor on an '09. It should be coil on plug. They do recommend plugs at 300 hours though, so you are getting close. You might try that - easy to do, inexpensive and almost due anyway. Have you cleaned and oiled the air filter recently? Too long ago and it may be dirty - just done and it may have too much oil - both restrict air flow. I'd start there and see what's what.


All mcx has cap and rotor

onewheat
06-09-2012, 01:28 AM
All mcx has cap and rotor

Yep, you are right. Not sure what I was thinking about... :uglyhamme :confused::confused::confused:

BTV
06-11-2012, 09:57 PM
I tried filling up with 91 octane and adding Stabil ethanol treatment this weekend and still had the problem starting. Engine did start fine when cool, but when hot had to crank about 10 seconds to start. I took the cap and rotor off today. Doesn't look bad to me, but I don't know what's good or bad. Does it look bad to you?
80094

80095


Any thoughts on being hard to start when hot?

Thanks

JimN
06-11-2012, 10:08 PM
I tried filling up with 91 octane and adding Stabil ethanol treatment this weekend and still had the problem starting. Engine did start fine when cool, but when hot had to crank about 10 seconds to start. I took the cap and rotor off today. Doesn't look bad to me, but I don't know what's good or bad. Does it look bad to you?
80094

80095


Any thoughts on being hard to start when hot?

Thanks

Want to show the rotor?

Did you take a fuel sample, or just assume it needs StaBil? If the gas is bad, adding some kind of treatment won't help to bring the gas back to life.

Hot starts- does the exhaust smell strongly of gasoline?

BTV
06-11-2012, 10:29 PM
The stabil was a suggestion to help if I had bought bad gas. I don't think thats it, but pretty cheap to try. I can't get a very good rotor pic. It does look a little burned on the tip. No smell of gas in the exhaust. Thanks
80097

BTV
06-11-2012, 10:34 PM
Tried another pic of rotor
80100

snork
06-11-2012, 10:57 PM
definitely replace cap and rotor and most likely plugs

JimN
06-12-2012, 07:32 AM
definitely replace cap and rotor and most likely plugs

I would at least check the intensity of the spark, timing and consistent firing.

BTV
06-12-2012, 08:09 PM
Changed cap and rotor this afternoon. Engine fired right up when cool. Warmed it up and turned off, immediately restarted just fine. Let it sit about 5-10 minutes and it was hard to start. Not hard to start every time when warm, just sometimes.

Anybody have any ideas what I should check next?

Thanks

sand2snow22
06-12-2012, 08:16 PM
Not really sure how it happens, but search vapor lock on here...

Footin
06-12-2012, 08:31 PM
Try running the blower for a minute or two, it cools down the engine compartment and may help if it is vapor lock.

ntidsl
06-13-2012, 11:36 AM
Fuel pressure loss for some reason when warm.

JimN
06-13-2012, 12:32 PM
You don't get vapor lock when the pump is in the tank- that, and the need for higher fuel pressure with injected engines is why they started putting it back there. The fuel is pushed to the engine, not pulled.

ntidsl
06-13-2012, 12:35 PM
I didn't think MCX's can vapor lock! Thanks for reassuring Jimn!!!

MrPink
06-13-2012, 02:27 PM
I had a similar mysterious issue on my 09 X2 and discovered it was a partly separated wiring harness that connects to the fuel pump. It seemed like when the motor got hot the plastic connector would heat up and start to separate and cut power to the pump. It always started no problem cold and then if i let idle for 5-10 minutes it would shut off. Good luck in your search.

BTV
06-13-2012, 10:40 PM
Thanks for ideas. I'll go over all connections carefully and hope problem doesn't get any worse.

rawly
06-14-2012, 12:19 AM
Mine had the same issue and it was because the fuel pump ground wire inside of the tank was loose.The poor grounding caused the connector that plugs into the pump to slightly melt.Turn the key to the on position and listen for the pump to come on.You should hear the humming sound from the drivers seat.The wires should not get hot when the boat is running.

gstringlover
06-17-2012, 12:07 AM
its probably that acordian fuel pipe from pump to sender presure pipe in tank and 1 piece, its probably cracked,,, but it could be many other things,, did u scan the boat when hot or for codes
?

gstringlover
06-17-2012, 09:29 PM
its probably that acordian fuel pipe from pump to sender presure pipe in tank and 1 piece, its probably cracked,,, but it could be many other things,, did u scan the boat when hot or for codes
?