When replace plugs?

[scoflaw]

The auto vs. marine cap is no big deal. There is no vent on the cap it's on the Diz housing

 

[Henry Boyd]

So... you used a non-marine dist cap and moved the label over to it to "make it compliant"? A label doesn't prevent it from going boom. You don't have to buy the Merc brand, but for safety, get a proper marine version.

The current line of Merc/Quicksilver brand do have brass contacts, by the way (and for quite while).

Dennis,

This is the guy whose philosophy of sterndrive repair is “Jack Daniels and brute force”. I’m not sure a little thing like science and logic is going to change him.

 

[Lazy Daze]

The auto vs. marine cap is no big deal. There is no vent on the cap it's on the Diz housing

Are you sure there's nothing on the cap, itself? I don't have one in front of me to check right now but I could have sworn there was. Without a doubt, some things can definitely be shared between the auto and marine world - often at a significant cost savings. But I would question why there is an Ignition Protected cert on it if it wasn't needed... after all, it costs money to get that cert and why would they bother if it wasn't needed, you know?

Henry - maybe I'll have a JD tonight and see what I can accomplish!

 

[juggernaut1]

FYI NGK doesn't recommend putting anything on the plug threads. I boat in salt and mine came out easily after 5 years, so I didn't apply anything on the new plug threads when I replaced them.

 

[scoflaw]

Are you sure there's nothing on the cap, itself? I don't have one in front of me to check right now but I could have sworn there was. Without a doubt, some things can definitely be shared between the auto and marine world - often at a significant cost savings. But I would question why there is an Ignition Protected cert on it if it wasn't needed... after all, it costs money to get that cert and why would they bother if it wasn't needed, you know?

Henry - maybe I'll have a JD tonight and see what I can accomplish!

Same cap check it out

FYI NGK doesn't recommend putting anything on the plug threads. I boat in salt and mine came out easily after 5 years, so I didn't apply anything on the new plug threads when I replaced them.

A little bit of snake snot never hurts only helps

 

[juggernaut1]

Same cap check it out

A little bit of snake snot never hurts only helps

NGK iridiums plugs have a plating on the threads already. They recommend against the use of anti-seize due to the increased risk of over tightening and stripping the thread.

 

[scoflaw]

NGK iridiums plugs have a plating on the threads already. They recommend against the use of anti-seize due to the increased risk of over tightening and stripping the thread.

I suppose if you don't know what your doing anything is possible. Agree about never seeing them rust.

Now you have to convince Henry that they don't need to be changed every 2 years. LOL. People that don't do their own wrenching just don't understand.

 

[WV 320 Dancer]

So when I bought my new to me 2003 320 Nov. 2018 I got all the past maintenance records. I replaced all the plugs new cap and rotor. The set I put in was only the third set to ever go in the boat.

 

[Arminius]

I think I bought an auto cap for my boat but will not replace. My original intent was to purchase the new cap at the marina and get free advice too but they had "reduced hours" so I turned to the Internet. Googling the options, there was a "buyer beware" price discrepancy but cheap does not necessarily mean bad. Research indicated brass posts were superior and Mercruiser must have been saving bucks to have used aluminum. I ordered but inspected the old cap the following day and saw the decal "J-1411?" At one time all electrical parts in navigable waters (CG jurisdiction) were required to display them. Unclear now but production is to be in compliance. Going back to the BB (seller) site, I saw other caps were advertised as being produced in compliance but saw no such regarding the "crab" style. I then wrote seller who said "they were same as factory caps." As far as I was concerned, this was an implied admission they were not produced in accord with marine specs but were repurposed auto/truck inventory. Getting complicated, new part arrived and same as old except superior in that it had embedded washers and and brass posts. No worse atmospheric sealing. This is a repurposed 1956 Chev engine, after all. Also, my engine compartment is protected by a FM-200 auto suppression system with auto engine/blower shutdown. As a bldg architect once explained, the Code allows lots of money saving shortcuts if you sprinkle the bldg. So, in response, I say " You're right! (This is one of the two effective ways to silence my girlfriend.)

 

[Arminius]

Cap warning! The hold down screws that came with the cheaper cap I used and discussed above came with new screws with the wrong thread. I had the old screws and used them, adding my own Loc-Tite. There are negative reviews at the Amazon web site which I suspect resulted from purchasers using the new screws and trying to run with a loose or poorly seated cap. This reminds me of how I lost a friend many years ago. Apparently, at a party, I had told the guy that he could use an auto coil in his boat. Later, he and his girlfriend drifted for many hours off BC before being rescued. They had plenty of time to dwell upon how they ended up with a burned out coil. Eventually confronted, I explained that they must have erroneously purchased a resistor type coil. Some cars furnish a reduced voltage to the coil except when the resistor is bypassed in the starting circuit. This didn't make it right.