Smoking engine... Nc30 (Valve stem seals?)

[talcumpowderbut]

Ok i have had this problem for a wee while and just gave up on the vfr for a short while but have spent that much money and time on the poor thing i think its worth trying to fix this problem. Originally i thought it was old oil on the manifold burning off, but i have been told it is a valve stem seal. I was also told that i could get another engine for £70 from ireland but that was bullshit. Anyway so i have decided to take it upon myself and hopefully repair the existing engine. So i need to know how hard it is to do ( what tools are needed) How expensive, and what should i replace while the engine is apart while i am in there. As it is 48k km engine. Any help would be appreciated. cheers connor

[scooble]

first of all, run the engine for a while, remove the carbs and look down the inlets. If you have oily inlets then the seals have gone.
Don't use the pattern ones you get in a complete gasket set, they're shyte (I found that out the hard way).
I got my second set from Rik O and they were great.

You'll need a spring compressor. Some require you to take the head off, whilst other don't.
I took the heads off mine because they were leaking anyway and used one of those G clamp type compressors.
Make sure you have 16 little pots handy all labled up for each of the valves, collets and springs.
Getting them out is quite easy, all you need to do is prize them off and getting new ones on is easy too.
Hopefully the clearances won't change much, buts its worth checking them again once everything is back in place.

You'll maybe need a set of head gaskets too if the head comes off, they can be quite expensive, seals I think are about £30.

I'd never done a 16v 4T before, but am pretty experienced with 2T's. The Haynes manual isn't bad, and if you feel a bit nervous, take your time and ask lots of questions on the forum.

[talcumpowderbut]

Hey thanks very much for the info.Next time i am able to work on the bike. I will take the steps to confirm that it is the seals. I also have a haynes manual to follow. cheers again. Much appreciated :)

[dobbslc]

Is it smoking all the time or just when you're coming off the throttle? From hot cold or both?
I had an old GSXR 400 that had oil in the can from a previous blow up that took ages to burn off.
If it's smoking all the time it's probably the rings

[StrayAlien]

Yes, good to know what is the problerm first. General rule of thumb as I know it: smoky when giving it gas = rings, smokey when backing off = valve guide seals - but I am no expert.

However, I have just these last weeks done my valve guide seals and given the head a bit of a refurb as well. I used the Haynes manual and some questions here on this forum. The Haynes manual tells you everything you need to know. Just read it carefully. I have never done it before so I tiook it slow and careful.

All going well, with the heads off the only other part you will likely need (besides the guide seals) is the head gaskets. The oring for the engine timing cover is supposed to be replaced, but I know lots of people would not.

To get things apart you will need:
* a valve spring compressor. I got mine for $25 on ebay.
* socket set
* maybe a rubber mallet to help nudge the heads off if they seem stuck

To inspect things when apart you will need:
* a micrometer for check valve stem sizes and cam wear etc. I didn't go as far as checking valve guide bores (I don't have that tool)
* if you are checking the valve spring lengths as per haynes, then you'll need a vernier caliper. I have some not-very-expensive non-digital ones and they are immensely useful.

If you are relapping the valves, then you'll need valve grinding paste and a valve holding sucky-cuppy thing. These are small valves so get a small one. They often come in a set, just make sure it has a very small one in there. I used water based pastes and not oil based. Easier to get out of everywhere. And you DO want to get it out of everywhere.

For reassembly:
* a micrometer for checking shim sizes on reassembly.
* A torque wrench
* Moly grease and some oil (and a mixture of both at the same time)
* Feeler guages to check valve clearances. If any are out, you'll be up for some shims.

I have a smaller compressor which was priceless for cleaning stuff. Also good to have a few liters of brake cleaner or some cleaning solvent handy.

I used a dremel for de-coking the valves and exhaust ports and cleaning up all bolt threads before reassembly.

.. and I took plenty of photos of stuff during dissasembly showing things in-situ and with any relevent markings shown.

All in all, it was not a difficult job, just took time.

Greg.

[talcumpowderbut]

thanks so much guys. honestly i would be lost without the internet haha. I the last couple of times i had it running it didnt seem to smoke at all. But i was not hard on the revs as it was late at night in my shed with niebhours near who im worried will complain haha. i think im going to get someone to have a proper look at it and give me an expert opinion
. And then i will take it from there. Before i strip the engine and find out its all good. But seriously thanks so much.