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mjr119
09-02-2015, 04:09 PM
I replaced my plugs a few weeks ago (AC Delco, not sure of the part nubmer, I think I got it out of the manual, will need to double check).

The boat immediately started running kind of rough. Like it has a slight miss. It is only noticeable at idle or barely cruising below about 10 mph. If you throttle up to wakeboard speeds you cant feel it. it may still be happening, but it isnt noticeable like at idle.

When I had the boat weighted heavily for surfing, it was extremely noticeable! I could hear it cutting out while surfing.

Any ideas what could cause this? I did not replace the plug wires. Could it be the plugs?

Which plug is everyone else using?

gregski
09-02-2015, 06:09 PM
What gap did you set?

mjr119
09-02-2015, 06:11 PM
I did not change the gap. The plug specs were the same as what the manual calls for. I realize that they could be off from the factory. I didn't check them. Could this be the issue?

gregski
09-02-2015, 06:18 PM
My experience with regular plugs is that the gap is not set by the manufacturer. I guess I don't know for these. I never install new plugs without checking.

Also, were the new plugs the same length as the old plugs?

mmandley
09-02-2015, 07:18 PM
If you made sure the same gap was used for the new plugs as the boat manual calls for but you now have missing, you might have a damaged plug wire. This happens quite a bit when replacing them. If any of them were hard to remove, you might have broke the connection point from the wire to the connector on the plug.

My bet would be to replace the wires as well.

brain_rinse
09-02-2015, 07:38 PM
Post the specific plugs you used and check the gap on one of of them.

5:00
09-02-2015, 09:17 PM
+1 on the broken wire. It may be arcing inside the boot or cable if broken. It may also be that the boot didn't go on all the way or not correctly. The top of plug can go between the metal piece and the boot. Check the gaps as mentioned.
Be sure the top of the plug is screwed on fully. I had one back out once and was arcing. It ran but really rough. Let us know what you find.

mjr119
09-02-2015, 09:34 PM
Some caps were extremely hard to remove. I did check to make sure the caps were pressed on firmly. They all seemed to be good. I'd like to replace the plug wires. I had planned to do it at the end of the season anyways. Close enough I guess. Where is the best place to buy? Brands? Links?

mjr119
09-02-2015, 09:35 PM
Plug wires are blue and have numbered stickers on them. Not sure if original or not. Thanks for the replies everyone.

mjr119
09-02-2015, 10:44 PM
http://www.skidim.com/mobile/WIRE-SET-DELCO-INDMAR-OEM-GM-57/productinfo/75%2D6002/

is this what I need? If so is there a napa cross reference part number?

Crane man
09-02-2015, 11:43 PM
This may sound dumb but in my experience with bad plugs and wires turn on your radio to an am station and start,the engine. And arc to ground or,missfire will sound like lightning crackle through,the stereo. I have used this to find cracked plugs and wires many times. The high current arc disrupts the radio signal and at idle you will feel the,miss at the,same time you hear it.

mjr119
09-03-2015, 08:53 AM
I'll try that today. Hopefully it's just plug wires. They look old. Can anyone confirm that Napa will have what I need? Plan to go by there today after work but if I dont have a part number they will NOT be able to help me haha.

brain_rinse
09-03-2015, 09:53 AM
They will not have what you need. The plug wires are extra long.

Poison
09-03-2015, 09:55 AM
I changed plugs and distributor cap/rotor about a month ago. When I put it all back together, it was missing pretty badly when I pushed up the throttle. It wound up being the plug wires. Swapped out a new set and it ran perfectly.

As far as part number, it depends. I called inboard online and they got me set up. Mine has the HVS distributor. If you call skidim, inboardonline, or Atlanta Marine, any of those folks should be able to get you pointed in the right direction. Take a look through this list:
http://store.inboardonline.com/iwwida.pvx?;products_no_tree?cat=2150

mjr119
09-03-2015, 09:59 AM
I used mr43lts plugs.

mjr119
09-03-2015, 12:44 PM
I have the Delco distributor. I called ATL Marine and they couldn't tell me which plug wires I need unless I give them the engine serial number. WTF why is it everytime I try to get parts for my boat, even if it's simple, no one can tell me without a serial number. I can't even order a damn oil filter without having my serial number.

I mean did Indmar really change plug wires mid year? Or have they been the same, depending on the distributor, for years?

mjr119
09-03-2015, 04:39 PM
Unreal, no one will tell me which wires I need without the serial number. Why is that? Wtf does the engine serial number have to do with the distributor and plug wires? I told them which distributor I had, which engine model, year, everything. I dont have the serial number at work or I would obviously just give it to them.

kaneboats
09-04-2015, 08:49 AM
It could be just the software the dealers use. It requires serial # to see which engine, etc. you have. They might not know how to look it up any other way.

VA LSV
09-04-2015, 09:57 AM
Should be this set from Skidim.
http://www.skidim.com/WIRE-SET-DELCO-INDMAR-OEM-GM-57/productinfo/75-6002/

Distributor change took place in '06. Gap should be .045 for the MR43LTS plugs.

mjr119
09-04-2015, 10:06 AM
Thanks! That's exactly what I told ATL marine, but they weren't having it. Guess I will just order from SKIDIM.

mjr119
09-04-2015, 01:09 PM
It could be just the software the dealers use. It requires serial # to see which engine, etc. you have. They might not know how to look it up any other way.

You're probably right. I expect this from my local boat shop, they don't even work on inboards. I just thought ATL Marine was the go to Moomba specialist that could help me out.

mjr119
09-09-2015, 03:22 PM
My new plug wires came in today. Will be installing them after work. Probably won't get to test it until Friday. But Im pretty sure this will clean up the stumble.

Thanks to SKIDIM. Super easy to deal with and very fast shipping. I just found out that they are in SC, about 2 hours away from me! So shipping is basically next day! I probably wont shop anywhere else for boat parts!

mjr119
09-09-2015, 07:59 PM
23001

Taylor pro wires. Seem to be good quality. Now I need to clean up the engine.

Garn
09-16-2015, 12:14 PM
I had the exact same problem after I changed my plugs. It ended up being one of the plugs was cracked.

JoelFett
09-16-2015, 02:46 PM
My new plug wires came in today. Will be installing them after work. Probably won't get to test it until Friday. But Im pretty sure this will clean up the stumble.

Thanks to SKIDIM. Super easy to deal with and very fast shipping. I just found out that they are in SC, about 2 hours away from me! So shipping is basically next day! I probably wont shop anywhere else for boat parts!

I Love them! I needed some plug wires for the old boat earlier this season, on a Saturday, and called a buddy of mine. He gave me their home number and they opened on a Saturday, and got me the parts as I was driving there (15 minutes away) This store is basically a garage behind their house, but they have EVERYTHING in stock. Blows my mind that they are so close, so stocked, and so awesome. Gotta love good people.

mjr119
09-16-2015, 03:13 PM
The plug wires fixed my issue, but now I have a vdrive problem. So I am probably done for the season.

That's awesome, JoelFett! It is rare for a place to have parts in stock anymore. My plug wires came in a ziplock baggie with the part # sharpied on it lol. I suspected it was a mom and pop shop. I'm very pleased with the transaction and I will be supporting them in the future!