Intermintent idle miss

[bigtbassman]

In order to get stabil into system for winter I ran 2003 225hp 280 hrs ,optimax on muffs for 30 mins. Seemed to idle fine. Changed plugs, did compression test. Now it seems that I have a slight miss, stumble Pulled plugs to look for cracks all seemed good. I'm thinking by ideling that long I might have carbon built up in injector. I would like to try seaform in the vst to see if I can clear it up. I will not be able to run at high speed until spring. Can someone explain how the process of putting seafoam into the vst? Do I remove the red capped filter and pour it in there after emptying the fuel out of vst. How much to put in. I guess it could be a bad plug but in my 50 years on working on different engines this has never been the case. Thanks T

[Bryanmc57]

Silly question, but did you check the gaps before you installed the plugs?

[bigtbassman]

YEP

[Bryanmc57]

Well, if it didn't miss before you installed the new plugs, and it had a miss after you installed the new plugs, common sense points toward an issue with the new plugs.

[bigtbassman]

Thats why I hate to post. There is always some smart ass remarks. A bad plug will not be intermintent. Forget it, I'll post on another site and hopefully I'll get some ernest answers. T

[Bryanmc57]

It's not a smart ass remark, it's from experience. If something wasn't happening before you did something and started happening after you did something, it's highly probable that it's related to what you did. Sorry you got butt hurt.

[lpugh]

Thats why I hate to post. There is always some smart ass remarks. A bad plug will not be intermintent. Forget it, I'll post on another site and hopefully I'll get some ernest answers. T

Yes they can be intermittiant, very long explanation as to why and dont have the time go into that right now, but I have seen intermittiant missfire from plugs more times than I can count especially if the motor is running a little lean or gap is set to close

Would also be a good idea to read the forum announcements and provide all pertinent info, like serial numbers

That was not a smart ass remark, just the smart thing to do in rechecking your work, every one makes mistakes at times, even me and Iam purfect

[bigtbassman]

Ran seafoam through the VST and the slight miss cleared up. Can't wait until spring to open it up. Thanks for the help. T

[EuropeanAM]

Please see the Announcements at the top of the Forum, and be sure to provide the Required Info when posting. Thanks!

Be careful about what you add into the VST and/or injection system as some products are not necessarily as safe as others.

Based on your results it does sound like you had some carbon buildup, though.

Please go easy on those that assist here- honestly the comments made were the same that crossed my mind initially. On that note, make sure you used the correct plugs (IZFR5G) gapped at .032-.033", and torqued to 20 lbs/ft (with a torque wrench). No substitute plugs.

[bigtbassman]

Thanks for all the posts. Although the miss is not as bad as it was I don't think it is idling as it should. I'm now leaning toward getting rid of the metal reeds and going with one of those suggested on BBC. After reviewing almost every post on reed problems and repair I am more confused than ever. I'll keep reading, my wife says it keeps me busy. I have several months to decide and make repairs due to winter has hit here in Idaho. Thanks to Don and Chris for all their posts on the subject. T