Spark plug caps

[thejollysinker]

One of my caps is starting to rot on the metal bit that snaps onto the plug’s threaded end. 
Question: can I unscrew it from the HT lead and replace it or am I looking at replacing the coil pack as a whole?

 The engine is a 2001 Yamaha F60. I had a fiddle with it yesterday and it gave me the impression that I could unscrew it and replace.

meanwhile I have a new fuel filter that doesn’t fit my housing that I’ll post if anyone can use it…. Photo with part number here 👇

 

Edited August 20, 2023 by thejollysinker

[Andy135]

I don't know about your engine specifically but I'd be surprised if the leads weren't replaceable.

[thejollysinker]

23 minutes ago, Andy135 said:

I don't know about your engine specifically but I'd be surprised if the leads weren't replaceable.

They look like they are but, I happened upon another forum where one member was insistent that if you unscrewed the lead from the coil pack there was no going back….

Atm I have some fine s/s wire wrapped around the threaded part of the plug which isn’t ideal but ‘works’.

[Andy135]

2 hours ago, thejollysinker said:

They look like they are but, I happened upon another forum where one member was insistent that if you unscrewed the lead from the coil pack there was no going back….

Atm I have some fine s/s wire wrapped around the threaded part of the plug which isn’t ideal but ‘works’.

He may be right - I'm looking at it from a car engine perspective but I can see why a marine engine manufacturer would want to seal the joint.

[Gordmac]

Make it waterproof? Sell more expensive parts?

If you can find a parts catalogue, if the lead is available separately it will have a part number.

[mick]

Just googled it and the genuine plug cap is about £60 and screws onto lead.

[thejollysinker]

Thanks for the info mate.
60 smackers for a spark plug cap 😳

I’ll get 4 and some spares 🤣

[suzook12]

looked on boats.net, full lead and plug is replaceable.

Now, I would imagine, if you slide the rubber boot off, there will be a plastic spring clip in there that holds the lead in on the spike. As for the caps themselves, just make sure whether or not they are resistor caps. Resistor caps are usually 5K ohms.... No reason why you couldn't  use whatever plug cap you want.

[thejollysinker]

12 hours ago, suzook12 said:

looked on boats.net, full lead and plug is replaceable.

Now, I would imagine, if you slide the rubber boot off, there will be a plastic spring clip in there that holds the lead in on the spike. As for the caps themselves, just make sure whether or not they are resistor caps. Resistor caps are usually 5K ohms.... No reason why you couldn't  use whatever plug cap you want.

That’s really helpful. Good to know I can’t break anything if I start pulling things apart 👍

I’ll give them a test with the meter to find out if they are resistor caps, didn’t know there was such a thing 🤷‍♂️ and I did wonder about using something else apart from OEM products which seem overly expensive for what they are.

Thanks for your help 🙂

[thejollysinker]

On 8/22/2023 at 6:46 PM, suzook12 said:

looked on boats.net, full lead and plug is replaceable.

Now, I would imagine, if you slide the rubber boot off, there will be a plastic spring clip in there that holds the lead in on the spike. As for the caps themselves, just make sure whether or not they are resistor caps. Resistor caps are usually 5K ohms.... No reason why you couldn't  use whatever plug cap you want.

UPDATE:

pulled the rubber caps off the coils to find that the leads are sealed in place with what looks like some kind of resin so no new leads are going to fitted.

I had ordered some new HT lead wire and 5K Ohm Champion rubber caps (which didn't cost a lot) so will just fit the caps which should be enough to sort the problem out.

 

[suzook12]

On 9/17/2023 at 5:14 PM, thejollysinker said:

UPDATE:

pulled the rubber caps off the coils to find that the leads are sealed in place with what looks like some kind of resin so no new leads are going to fitted.

I had ordered some new HT lead wire and 5K Ohm Champion rubber caps (which didn't cost a lot) so will just fit the caps which should be enough to sort the problem out.

 

That's odd.

Hopefully the caps will do the trick

👍