Mercruiser 5.0 mpi coil replacement

[ronaca88]

Good day guys.

I have a question hoping you can help me. My merc (Serial number 2A189803) needs a coil replacement. In the parts catalog, the part number is 863704T. Looking at the part number, it seems that is an assembly of the coil and the ignition module together, making the part +$250 USD. Is there a way to buy only the coil? Any experience in this engines?

I really appreciete any help.

See ya.[FONT=Arial, Helvetica, sans-serif] [/FONT]

 

[Fun Times]

If you shop eBay using the part numbers 'You can find similar parts in the $100.00 - $150.00 range...http://www.ebay.com/sch/i.html?_from...3704T&_sacat=0

http://bpi.ebasicpower.com/shop/inde...ducts_id=14207

Seems rare that this coil goes/went out so soon. Are you sure it's bad? Is the engine still under warranty? Yegboats may be able to tell if needed.

An auto parts store might be able to match something up using a GM engine model. Here's a test procedure for you if interested, http://easyautodiagnostics.com/gm/4....test-the-icm-1

 

[thumpar]

Coils are probably the most replaced item when it is not even the problem. I would do the diagnostics.

 

[Bondo]

My merc (Serial number 2A189803) needs a coil replacement.

Ayuh,.... Exactly how'd ya come to that conclusion,..??

 

[ronaca88]

"Seems rare that this coil goes/went out so soon. Are you sure it's bad? Is the engine still under warranty? Yegboats may be able to tell if needed."

Unfortunaly, there is no merc dealer where I am, so maintenance are performance by myself and my mecanic.

Because the boat is used on salt water, and the lack of design in the engine compartment from Tahoe, when you open the engine compartment, the water acumulated in the join starts dropping just above the coil. Here is a picture of how corroded it is right now.

At the time, my engine doesn.t have spark on the plugs and I think that the coil should be the problem. What do you think?

The other curious thing is that the scanner doesn?t give any fault other thant a rich sensor (o2). I really doubt this may be a problem, because that sensor is giving problems since forever.

 

[Yegboats]

Your warranty is up April 2 2016 :clock:

ENG: 2A189803 4M410RLUU MERCRUISER 5.0L ALPHA MPI DRV: 2A126321 5121200TS MERCRUISER ALPHA 1.47:1 TRN: 2A151810 6111001LS MERCRUISER ALPHA TRANSOM
Serial/Model:		4M410RLUU

 

[Fun Times]

Because the boat is used on salt water, and the lack of design in the engine compartment from Tahoe, when you open the engine compartment, the water acumulated in the join starts dropping just above the coil. Here is a picture of how corroded it is right now.

Looks like you'll have to become creative to help keep the accumulated rain water off the new coil assembly. The internals of the coil should be more water resistant but doubtful for being waterproof.

At the time, my engine doesn.t have spark on the plugs and I think that the coil should be the problem. What do you think?

Do you own a timing light? Since you have no spark at the spark plugs, you'll want to see if you have spark coming directly out of the ignition coil itself. The easiest way to check is to use a known good timing light and connect it up to the "coil wire" vs the plug wires and watch the light flash for a very consistent flash when cranking the engine over.

Also take note if the Tachometer gauge is moving or not during cranking...It should be reaching right around 350 RPM at crank.

Be sure to inspect all your wire connector pins for corrosion type damage and check the electrical connector weather packs to ensure they are seated correctly to help hold out water. http://www.bing.com/images/search?q= weather packs&qs=n&form=QBIR&pq=weather packs&sc=0-21&sp=-1&sk=

The other curious thing is that the scanner doesn?t give any fault other thant a rich sensor (o2). I really doubt this may be a problem, because that sensor is giving problems since forever.

Since your engine has the catalyst exhaust system, a defective o2 sensor (or cat) won't affect your no spark issue but it "could" be interfering with your overall engine performance to where if it was "at all" possible, it would of been nice to have it inspected and repaired on Mercruiser's dime vs yours especially should the catalyst inside the exhaust manifold system be damaged for some other reason.

Be sure to follow your owners manual for the correct engine oils to use as the wrong oil could damage the cat system.

Have you inspected the spark plugs for the side the scan tool says the o2 is bad?

Engine Model Notes: MERCRUISER 5.0MPI A EC 2R 5.0L ALPHA MPI.

 

[Fun Times]

Your warranty is up April 2 2016 :clock:

Thanks Yegboats for the information. :thumb:

Guess it could have been worse and ended on April 1st April fools day.:wof:

 

[ronaca88]

Thanks all for the help.

Today, we replace the coil for one that is working (not new) and it runs. Defenitly, I have to keep the water out of the coil. I will be creating a water channel to keep the water running to the sides of the engines and not to the engine directly.

For now, I will try to buy only a new coil, and trying to protect it self with some kind of cover, besides the water channel.

I will post some photos in here of how it is.

Thanks again!!

 

[Captmoab]

Question
I have a 2006 Stingray with the mcm 5.0 mpi and was wondering if there is a hotter coil available that plugs right in and works?
Thanks in advance