Valve Stem Seal Replacement Without Removing Head

[leener]

Guys, just after some verification about what I'm about to do... Next weekend, maybe... If it isn't raining. Just need to make sure I'm not about to dive in and mess it up.

I need to get it going, because I will be selling up and want this bike to be working properly for the next owner, so I have a fighting chance of getting a good price.

I have determined that the Triumph 955i (2003) has weeping stem seals, because the bike only spews up some blue smoke when warming up, but has no trouble when riding, after it is warmed up. The plugs get fouled up in C1 and C3 (more in C1), and I am going to replace the stem seals on the exhaust side.

Although, hot compression was a little lower on C1 and C3, compared to C2, it wasn't MILES off, so hopefully there isn't much or any blow-by. It runs fine when the oil has burnt away.

I have placed an order for new seals, have a new oil filter on the way, and have some idea on what to do.

So here is the plan...

- Remove tank and airbox

- Unbolt rocker cover

- Remove plugs

- Set engine to TDC and make sure I recognise TDC on the crank shaft, as I might need to be cranking it over with no cams!

- Take out the CCT

- Remove and clean cams, plus inspect for damage

- Support chain (unsure what to do with this, as the engine will maybe get cranked again, with a free floating cam chain...

- Remove buckets and shims, keeping them in the right order to go back in

- Feed rope down cylinder 1's spark plug hole to fill it up, stopping the valves from dropping in, making sure to have the piston at TDC. As I am focusing on C1 and C3, both pistons should be at the top, already.

- Go to valve 1, hold a deep socket over it, and SMACK that bugger down with a hammer to compress the spring

- The cotter pins (what you call them?) should fall out, and the springs should be able to be pulled away

- Mop up any oil pooling around

- Now I should be able to get the stem seal out and fit the new one, pushing the new one snugly on as tight as I can get it

- Grab some strong cable ties and compress the springs down, before feeding them back over the valve stem

- Lay pins back in, keeping everything back where it belongs, and snip the cable ties to boing the springs up

- Repeat for each valve

- Put everything back together

Hopefully I have this right.

[SlowBusa]

I wouldnt trust the mark for TDC on the crank shaft

Get yourself one of these stick it down the spark plug hole and get a true reading of TDC

[Joeman]

Ambitious project!!

The rope might work if you have the piston below tdc feed in as much rope as you can then turn the crank to compress the rope again the underside of the valve...

Buy spare valve collets because yours are going to scatter when the valve spring rebounds!!

[SlowBusa]

Yeh best to pop some rag into the spark plug holes ......you dont want a rogue collet dropping into a spark plug hole....then you will have to take the head off

[oldgrump]

Question! how you going to compress springs to get collets back in?? if you taken cams out etc to put new seals in, wouldn't it be quicker to remove head as one lump and do them on bench!! you'll need to compress spring quite away down to fit collets back in!!!

[megawatt]

You'll be extremely lucky if collets jump out, more likely jam half out. If you must do it with head on, make a lever that you can use with a bolt on the head, to compress the valve springs. Cut a slot on two sides of the socket, so that you can remove collets with a magnet or tweasers. You can also use it to rebuild.

[Mr Fro]

Question! how you going to compress springs to get collets back in?? if you taken cams out etc to put new seals in, wouldn't it be quicker to remove head as one lump and do them on bench!! you'll need to compress spring quite away down to fit collets back in!!!

 

I was going to say the same thing. You need to squish those buggers down quite a way to get the collets back in. Besides, I doubt there will be room for the retainer with two or three cable ties in there too.

I think you'd be better off knocking up a lever that pivots on the can bearing bolts.

Edit: bloody hell [mention]megawatt[/mention] , beat me to it!.

[SlowBusa]

Ive seen it done on a car engine on youtube

but a bike is smaller and space is more restricted

But some bike mechanics do it the way [mention]leener[/mention] is talking about

[TimR]

Air compressor and adaptor in plug hole or has been done using a compression tester .

Remove cams so all valves closed ..build up pressure and 99.9% of time it works and allows spring compression to remove collets etc

But if you have a dodgy seal your screwed .

[Bianco2564]

Air compressor and adaptor in plug hole or has been done using a compression tester .

Remove cams so all valves closed ..build up pressure and 99.9% of time it works and allows spring compression to remove collets etc

But if you have a dodgy seal your screwed .

 

Done this numerous time on race engines works just fine.

We have a special tool knocked up that is basically a threaded spring compressor on a bracket,the bracket bolts to the head on any suitable threads.

It would require you to fabricate such a bracket to suit the trumpet and be sure it fits all the cylinders.

Also on another engine type we used a lever under a bar that was bolted to the head.

If both cams are out,set the piston at BDC on the cyl you are working on so the air pressure doesn't flip the engine over and tangle the chain up.

It can be a time consuming faff, and have to say for the sake of just whipping a few head bolts out of your engine you could spend hours making it work when having the head off would be more straight forward.

[megawatt]

And if you take the head off, you can check the valve sealing faces, valve seat conditions and valve runout. All off which affect cylinder pressure.

You can also get the valves refaced, seats recut and valve guides replaced.

[fastbob]

Feeding rope into the combustion chambers ? Wow, that's a new one on me . Is this a tried and tested practice or an ingenious idea ? Personally I would bite the bullet and get the head off and onto a work bench . Its going to cost you a top end gasket set though . Good luck

[fastbob]

Air compressor and adaptor in plug hole or has been done using a compression tester .

Remove cams so all valves closed ..build up pressure and 99.9% of time it works and allows spring compression to remove collets etc

But if you have a dodgy seal your screwed .

 

Well the object of the exercise is to replace some dodgy seals so ........

[Joeman]

Air compressor and adaptor in plug hole or has been done using a compression tester .

Remove cams so all valves closed ..build up pressure and 99.9% of time it works and allows spring compression to remove collets etc

But if you have a dodgy seal your screwed .

 

Well the object of the exercise is to replace some dodgy seals so ........

Meant valve seat seal not stem seal. If the valve doesn't close properly you won't be able to maintain the pressure in the cylinder to keep the valve up and it could drop into the combustion chamber. Then it's a head-off job to recover the valves.

[fastbob]

Air compressor and adaptor in plug hole or has been done using a compression tester .

Remove cams so all valves closed ..build up pressure and 99.9% of time it works and allows spring compression to remove collets etc

But if you have a dodgy seal your screwed .

 

Well the object of the exercise is to replace some dodgy seals so ........

Meant valve seat seal not stem seal. If the valve doesn't close properly you won't be able to maintain the pressure in the cylinder to keep the valve up and it could drop into the combustion chamber. Then it's a head-off job to recover the valves.

 

Yes of course, wasn't thinking right there

[leener]

I was going to go down this route to do the job, without removing the cylinder head, purely to save cost. But, reading some of the comments has me thinking that it would probably be easier to take the head off, and do the job in the kitchen, rather than out in the elements.

The bit I'm struggling with is trying to find a replacement head gasket, online, because they all seem to come as a kit, costing a bloody fortune! And, I'll definitely want to replace it.

I think taking the head off is probably a good idea, because I am sure I have covered well over 1000 miles with this problem, and the valve will need a damned good clean, at least. Top of the piston will be gunked up, no doubt.

Trying to find a gasket...

[megawatt]

If you absolutely cannot find another head gasket, there is a slim chance that you can reuse the old one or make a new one from annealed copper.

[leener]

Tis a slim chance that you can reuse the old one or make a new one from annealed copper.

 

I am just going to have to give it my best shot using the method that I first conjured up, taking my time, and being as careful as possible. Removal of the head with a gasket that is 35k miles and 15 years old might end up costing a lot more to fix.

I need to shift the bike to fund a replacement car, with a baby on the way, now.

My 2000 Diesel Pug 306 with a Kawasaki ignition, no working horn or windscreen washer, perished aux belt, and blowing blue smoke, needs to go, too!

Weather isn't looking good for this weekend, so might take me a few weeks to get round to it.

[Joeman]

It's a lot of time and effort and cost for gasket kit etc.

I'd try advertising it with the issue listed so potential new buyers are aware. This time of year there are loads of people looking for winter projects.

[fastbob]

Tis a slim chance that you can reuse the old one or make a new one from annealed copper.

 

I am just going to have to give it my best shot using the method that I first conjured up, taking my time, and being as careful as possible. Removal of the head with a gasket that is 35k miles and 15 years old might end up costing a lot more to fix.

I need to shift the bike to fund a replacement car, with a baby on the way, now.

My 2000 Diesel Pug 306 with a Kawasaki ignition, no working horn or windscreen washer, perished aux belt, and blowing blue smoke, needs to go, too!

Weather isn't looking good for this weekend, so might take me a few weeks to get round to it.

Have you seen the company called Sprint Manufacturing?

[leener]

I have it for sale on Gumtree with the issue mentioned, but nobody is taking a bite.

I don't think it'll be easy to sell, anyway.

I just fired an email up to [email protected] to see if they can get a head gasket, so cheers for that, Bob. Hoping they'll quote a reasonable price.

It's a good idea to get it stripped, just to clean it up, and make sure that nothing else is wrong with it. Plus, I will reap the rewards of having tackled something that I have never done before. A year ago, engine's were a thing of pure wizardry to me, but now I got my head around everything... except gearboxes!

[oldgrump]

Can't you just buy a genuine Triumph Head Gasket? had a look on here but not sure what model yours is.http://www.worldoftriumph.com/triumph-motorcycle-parts.html, thought it was about £58.00.

[leener]

I had a response : T1153000 is £49.92 from Sprint Manufacturing for the head gasket. I think it's a good idea if I bite the bullet and do it.

Damn, they're quick. That said - it's a 5 day lead time on the part, from point of ordering direct from them.

It doesn't really make any difference to me, because - how many days and weeks have I had to put off doing stuff when it rains?

Wish I had a garage...

Lots of photos will be uploaded when I eventually start this.

So, now my plan is to remove the head and most likely replace the head gasket, as well.

This will enable me to take the whole thing indoors and work on it, without getting rain inside the engine. And, it will be a lot warmer, and I can have a beer while I'm at it.

[SlowBusa]

If you absolutely cannot find another head gasket, there is a slim chance that you can reuse the old one or make a new one from annealed copper.

 

I did this job a few month back and reused the gasket with copper coat

Ive spent 4 hours so far stripping the bike back down because the head gasket has started leaking

Get A NEW gasket and save doing the same job twice!

[fastbob]

Can't you just buy a genuine Triumph Head Gasket? had a look on here but not sure what model yours is.http://www.worldoftriumph.com/triumph-motorcycle-parts.html, thought it was about £58.00.

£52.92 I make it , not bad at all for genuine Triumph. The pattern ones I suggested were £122