Spark Plug Popped Out - CBR 600 F4i

[stinkwheel]

There are places that will fit them for you. It's an easy job if the head is off.

At the end of the day, you'd then have a known good head with known good cams and followers that go with it. I'd go so far as to say a head with plug inserts is better than one without in many ways.

I've seen me fit inserts to brand new parts for my Enfield, pre-empting the alloy stripping out (they have oddball fine threads which aren't well suited to alloy).

While the head is off, worth measuring the camchain to check it's within spec. Have a good look at the coolant hoses while you have the bodywork off and access to them. Likewise fuel lines and control cables. Make sure the exhaust studs are all in good order.

Maybe do the valve stem oil seals? The seals themselves are cheap.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[JackDG]

good tips stinky I'll look over those.

The other day browsing fleabay I did buy a head that was going for £75... (weak impulse control)

Just arrived and looks much cleaner / less used than my current head.

All the threads (including exhaust studs) look good, and it came populated with spark plugs, valves, buckets and shims.

Think I'll still get the original one repaired and maybe sell on or keep and sell the ebay one. no strong feelings either way

Question for the new head - the bucket and shims were all over the place from shipping so don't know which shim is for which valve. What's the process here? randomly assign them, install, measure clearance then re-arrange the shims / replace shims as necessary? Cheers!
____________________
1992 GPZ 500

[Nobby the Bastard]

[JackDG]

Perfect, thanks for the confirmation. Gonna be an expert at shimming

oh and I dont need to worry about anything with putting the cam shafts onto a new head?
____________________
1992 GPZ 500

[Nobby the Bastard]

So it didn't come with the cams? Thats also not good. Generally you aren't supposed to use cams from different engines.

I've heard of people doing it but it's generally best practice not to swap cams around. You should ideally also not move cam caps around even within the same engine.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[JackDG]

Got the thread inserts done, no. 1&4. full inserts as opposed to the helicoil. Measured all the shims from the other head and it works out that I can use these in the original head to get back to factory clearance without needing to buy any extras.

You were correct about spending most of my time removing gasket material. These lines left behind are a pain! Done the outside of the cam tunnel and starting on the upper right of far right cylinder.

Currently using a razor blade + carb clean. Any tips or just persistance?
____________________
1992 GPZ 500

[stinkwheel]

I've heard of people hammering the end of a piece of copper pipe flat and using that as a scraper but I always land up going back to a stanley knife blade with a bit of tape along the back to protect my fingers.

Th etip is if you feel like you are rushing, take a break and do something else for a bit before you gouge lumps out of the alloy.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[A100man]

If you round the corners of your tool you lessen the chance of digging a corner in. I have a well worn decorators scraper for this kind of work.
____________________
Now: A100, GT250A, XJ598, FZ750

Then: Fizz, RS200, KL250, XJ550, Laverda Alpina, XJ600, FZS600

[JackDG]

Finally got it back together - decided to replace a few sundries along the way (thermostat rubber, thermostat gasket, camcover o-rings etc.) so had to wait for the shipping.

It appears after having 1 & 4 thread insert, the plugs are sitting ever so slighty higher than 2&3 (maybe 2mm max).

But it starts up and seems to run fine! Just need to find some petrol to put some miles on it and build the confidence in the mechanics of it up again!

many thanks for everyones input on this, much appreciated!
____________________
1992 GPZ 500

[A100man]

Good result
____________________
Now: A100, GT250A, XJ598, FZ750

Then: Fizz, RS200, KL250, XJ550, Laverda Alpina, XJ600, FZS600

[sickpup]

[JackDG]

Yeah they used timeserts sickpup.

I'll be keeping a close eye and will update here if anything arises.
____________________
1992 GPZ 500

[Pete.]

Helicoils should not let combustion gases past because it's not the helicoil or plug thread that does the sealing, it's the sealing washer on the plug.
____________________
a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[sickpup]

[Jim Mc]

I'd have bought a new head personally.

[c_dug]