Technical 100hp spark plug torque setting.

[cooperman]

Well I did a sniffer test today when I came home and the engine was hot. According to the test I did (3) there wasn't anything picked up.

Did it with the engine running and not. The Blue Print test kit is good as far as I know, because it has 2 separate liquid containers that the gas gets pulled through.

I'm still undecided if I should leave the spark plugs set at 25Nm or slacken them down to 18-20Nm! The plugs should have a life span of around 10 years I've been told.

What's your thoughts

If it’s no hassle drop them down to 20Nm, put a little bit of copper grease on the threads to help with removal in the next few years!

 

[koalar]

It used less doing 500 miles in one day driving to France then it does using it 5 days a week doing the 14 mile round trip to work!

Unlikely to be head gasket then

I take it there's no steam out from the exhaust at startup apart from the normal, otherwise you would have said

Put some kitchen towel over the exhaust, if it's going down the exhaust it will be pink

Check the, sides of the radiator at the top, the sides are steel and do get pin holes from corrosion

I had a few core plugs, the ones on the ends are easy to spot, it runs out of the bell housing or the bottom of the timing guard

These are difficult to spot, being at the back

but if you put a torch on them they will be wet at the bottom edge

 

[koalar]

If it’s no hassle drop them down to 20Nm, put a little bit of copper grease on the threads to help with removal in the next few years!

The correct torque is 18nm dry

Greased needs reducing by approx 20% so around 15nm

It's not recommended to grease them any more, quality plugs are trivalent plated and will last the life of the plug

 

[koalar]

I'm still undecided if I should leave the spark plugs set at 25Nm or slacken them down to 18-20Nm! The plugs should have a life span of around 10 years I've been told.

What's your thoughts

I doubt they come out easy after 10 years, whatever you do there will be a carbon buildup on the last thread, removing plugs that been in that long in an alloy head is quite stressful

 

[KungFooPanda]

I'll reduce the torque down to 18Nm tomorrow if I get a chance. My coolant looks like it's staying at the same level

 

[A3jeroen]

For years (and years) I have torqued my plugs to 25 Nm without any problem. Now that I have a smaller torquewrench I do them at 18, but I do not feel bad about the older ones. I change the plugs every 2 years (appx 20.000 Km) though.

gr J

 

[koalar]

For years (and years) I have torqued my plugs to 25 Nm without any problem. Now that I have a smaller torquewrench I do them at 18, but I do not feel bad about the older ones. I change the plugs every 2 years (appx ) though.

gr J

Yep

Every few years is fine and easy to change

But Iridium plugs are expensive and are designed not to be changed

But after 100,000K, in a aluminium head, it can be quite a stressful experience