Marcon

So I've had my stock '99 Silverstone now for about a year, and to her credit... I love her to bits. Not for a lack of trying however - she has given me a fair share of trouble... nothing too serious until now, however; and hopefully still nothing too serious...

It started a couple of months ago. Following a new Exedy clutch install by a well credentialed engine shop south of Brisbane, I started having issues with what I thought may have been misfires, complete with CEL (throttle pos sensor).. Replacing the sensor didn't garner a fix. After this, the car spent 6 weeks garaged as I tripped around the USA, and when I came back... the misfires looked like they had disappeared.

About a week in, driving home from the city the misfire feeling started to come back, and a couple of k's from home the situation got a lot worse. The car has clearly dropped down to running on 3 cylinders, so I got it straight into Honda - lo-and-behold, had dropped an electrode from the spark plug on the 3rd cylinder. Yep, just like this one - https://www.s2ki.com/forums/index.ph...ic=313476&st=0


Replaced the (disastrously generic looking) plugs with OEM. Compression in the 3rd cylinder was lower than normal (~170) post install and test drive. Essentially, 2 weeks in and the car starts running rough once more. Honda have noted that (as per their instructions), their next step is to remove the head and physically inspect - something that I would rather have a performance shop do should it be entirely necessary.

Apologies for the essay - what I'm hoping for is anyone who has experience with this sort of electrode breakage, or knows of a shop in Brissie that might. I have somewhat given into the thought that this is valve/bore/piston replacing territory.. but there is always hope.

jbu88

Same thing happened to me a few weeks after purchasing my '01 in November. Car developed a ticking / knocking noise, my mechanic pulled the plugs and an electrode had snapped off. It damaged the valves, top of the piston and scored the block. Replaced it with a used motor, costly experience so soon after purchasing but now 6 months on I'm back in love with the S.

For the mechanically minded: For detonation to cause the electrode to break off would it have to be a long-term thing (that's what I thought). The reason I ask is it happened straight after I filled up with 95 at a really small remote town which would have next to no cars requiring premium fuel = crappy fuel sitting for a while. I only thought about this many months after, car was running fine on the fuel for the 100kms or so before it started ticking.

Cheers, Josh

TRD_Celica

Ditto, This new no name gas station pooped up around the corner with a free ATM so I just had to stop by and take advantage of the offer. Being lazy, I went ahead and filled up the tank as well and what do ya know, I started mis-firing 45 minutes later and comes to find out that the electrode snapped. The spark plugs I was using were 5 month old NGK platinum's

jbu88

Did you get the fuel tested? I only thought about bad fuel until after mine had all gone.

Marcon

So I've booked the car in with an engine team south of brisbane... They have rebuilt a handful of mustang engines for us in the past, and they've got some good SR20s build under their belt... I'm hoping that enough.. I've tried quite a few specialist shops in the area but none have any sort of sizable experience with the F20C, so I'm going with the mechanics that have done well for me before.

Josh, I'm assuming you looked into the rebuild/replace path.. Was there a specific reason you ended up replacing? I'm a little bit confused because most of the advice I've gotten is to repair, but almost everyone that has been directly affected by this issue has ended up going for a replacement.. I'm not sure if I'm missing something.

chris_barry

Were the plugs tight. If they were loose or only hand tight the heat path from the tip of the plug to the head is reduced, the tips start overheating and disintegrate.

The factory torque spec ( and even the revised spec from an early bulletin) doesnt fully crush the sealing washer on the plugs. After a while the washer crushes and the plugs come loose.

Teltale signs are soot around the plug threads and base of the plug when you take them out.

AusS2000

Marcon, I guess the end result you want is a new engine. Just gotta pick the best path to get there. If you can find a good low mileage long block for a decent price this is a good solution. A rebuild is a lot more work, more expensive if done right (new bearings, rings, possibly pistons etc) and does have a risk element (trained monkeys rebuilding engines) but all going well should result in a minty fresh engine.

chris_barry

Another option is to use thinwall sleeves in the block then use Cp or similar pistons.

If the bore is only slightly scratched then fitting oversized Honda pistons is also an option.

AusS2000

These are all options but I'm pretty sure once the lay person gets the quote on having it done a replacement secondhand engine will start to look really attractive.

s2kadrenalin

Considered a stroker kit?

EG would be the Brian Cowler 2.47L kit for $3300. Would eliminate most required OEM parts with the benefits of more all round power.