Valve Stem Seal Replacement Without Removing Head

[Bianco2564]

Yes, you can dress the shells, the caps just hold the shells in place. Lightly polishing the scratches will spread the oil film across the journal and not around the journal in a narrow strip.

 

Yes you can dress it with a bearing scraper,not something an inexperienced hand should attempt though.

If a bearing is seriously scored it should be replaced,crank polished or ground with appropriate sized shells and the cause of the scoring investigated.

You sat polish the scratches,do you mean scratches in the shell or journal?

[fastbob]

It might be worth remembering that the original intention here was to cure a smoky bike that turned out to be down on compression and not to blueprint he entire engine . Those bearing shells look pretty good to me . Yes , a click test wouldn't have been a bad idea but I would be inclined bolt the rods back up again once the cylinders have had a light hone . I have to say that dressing white metal bearing surfaces with anything containing abrasive particles goes against my instincts. My thinking is that if the shells had noticeable scoring then there would also have to be room for whatever did the damage to have got between the shell and the journal. As there is no significant scoring surely it follows that the bearing tolerances are most likely to be ok ? After all Leener did not report any rumbling or knocking before the project began . So , if it ain't broke ......

[leener]

All rings in spec, big ends clearance is fine and in spec, so all seems ok. Here are some pictures, however. Scoring is present, but not excessive. The clutch housing has some serious marks from some trauma.

I may have to have a think about what steps to take, next.

The bores were a little scored, but the diameter was the same all down. I carefully pushed a ring down all the way and checked each inch to see if the gap was always the same. No idea if anyone else tried this, but it is the best I can do with what little tools I have.

I am now being asked... or told to go take father in law to the shops so he can get his obesity prescription of sugar filled crap. Being the only able bodied person has its problems, because certain individuals are too lazy.

I need to finish this engine, but can’t to much else until the gasket kit arrives.

As it is, the low compression is not looking to be due to the pistons.

 

[leener]

 

I have been cleaning up the the top and bottom halves of the engine to get rid of vast amounts of dirt, mud, and caked up oil. The paintwork on the engine is not great, but I’ll cover that up.

I managed to extract two stuck half-bolts that had sheared off, on the stator cover port, and sanded (gently) the old gaskets off. Some more to do, but making good progress.

I’m going to do more investigation, but noticed a lot of grey sealant had got into the head gasket, which I must have ignored prior to fitting. Some had blocked one of the holes for the coolant, which teaches me to take my time and work cleaner, in future.

The work goes on...

[fastbob]

I saw an episode of Wheeler Dealers once where a cylinder head with valves installed was tested by a specialist for any leaks . It was placed on a device that consisted of a flat table with a rubber mat on it . A vacuum was applied for a period of time and two readings were taken to determine the efficiency of the valves . I think they were also checking for porousness because it was an old car . I bet if you Google around you might find a back street shop that does this . In fact , the same place could almost certainly have a look at the bores as well .

[leener]

I saw an episode of Wheeler Dealers once where a cylinder head with valves installed was tested by a specialist...

Cheers, mate. Good idea. I need to give one more look over and teat (TEST - my phone always autocorrects to “teat”) for leaks, and try to re assemble the engine, before doing another compression test while the lump is in the garden. I hope that I can suss this without cracking into the bank too much more.

 

Loadsa pics

I tell you what mate, your bolt keeping method is spot on.

When I did my ZXR I just chucked everything in a magnetic tray and trusted my memory.

 

Cheers . I’m trying to be as organised as possible.

I spent 30 minutes looking for the bleeding metal o-ring from the balancer shaft, what’s it called, only to find it had fell into my toolkit.

Not much space to work in, in a metal shed.

[fastbob]

Keep soldiering on !

[SlowBusa]

The clutch housing has some serious marks from some trauma.

 

 

Someone please correct me if im wrong but I think thats normal

Ive seen it before

"IF" memory serves me right its to do with balancing ?????

[leener]

Someone please correct me if im wrong but I think thats normal

Ive seen it before

"IF" memory serves me right its to do with balancing ?????

 

I’m only assuming that it’s normal. I never had any issues with this before, and can’t see any sign that the clutch was opened and attacked by a rabid dog.

I wonder how many other engines have these marks on the clutch.

First time I have ever had an engine open to this degree, so I’m spotting all sorts right of interesting stuff... like a B on the back of the piston rods.

[megawatt]

You wouldn't get marks like that from rotation of the clutch hub.

[SlowBusa]

Old Yamaha XT500 ...thats where ive seen them before........decades ago and that bike didnt have a problem either

[Stu]

The clutch housing has some serious marks from some trauma.

 

FC7A6EC1-913C-4E49-A420-06C60EE1C2D4.jpeg

Someone please correct me if im wrong but I think thats normal

Ive seen it before

"IF" memory serves me right its to do with balancing ?????

 

Yes I have seen it many times

[JRH]

The photos in my service manual show the same marks on the clutch basket.

[leener]

Nothing exciting. Just a bit of engine cleaning in advance of the weekend. Plenty to do.

Lots of nasty old gasket getting removed.

 

 

 

 

 

[leener]

Good day! I have had a productive one.

Hope everyone else is having an equally fun day as me.

I have reattached the crank halves, after a careful and sparing application of sealant, and ensuring that the crank balance shaft is positioned perfectly, as to not collide with the crank and big ends during cycle.

Checked and cleaned the hell out of everything, using my favourite aftershave (WD40), and reapplied loads of oil to journals, gears, and everything that needed it.

Followed the exact procedures, as dictated by the Haynes manual, and torqued up the crank case. It was fun, having to keep turning it round to repeat each half to higher specs. I enjoy the torque bit for some reason.

Checked to see that the crank spins freely, without and major tight spots. All seems ok so far.

Cleaned up the clutch cover and fitted it with new stainless steel bolts, carefully checking it sits perfectly.

Noticed shocking state of various engine covers and got sanding them down. Now they look very mad-max, but might end up leaving them like it.

The stator cover is the worst! I did my best.

I need the correct sump gasket, and stator gasket... or I could butcher the ones that I have. They were off an older model, but scissors are ok, right?

I’ll just order the right ones and wait.

Nearly there.

 

[SlowBusa]

You Really Went for it Didnt you

[megawatt]

Have you run it through all the gears?

[leener]

Have you run it through all the gears?

 

Will do that tomorrow. The gears are back in the same position as when it came apart, so should be fine. I am making sure that it's all assembled perfectly before hitting the starter.

Sprag clutch was easy enough to get back together.

I have used a hell of a lot of WD40.

 

You Really Went for it Didnt you

 

By the time I finish with this project, this bike is going to look nothing like it did before. It'll look like scrap, but will run great, I hope.

[megawatt]

Why did you use WD 40?

[leener]

Why did you use WD 40?

 

Cleaning off the vast quantity of dirt and oil from the casing. I had to add plenty of oil back in to make sure everything moves silky smooth, but when any crap got in the engine, I had to gently remove it with a clean cloth.

It's the only thing I have to clean, and honestly haven't looked into using anything else.

The biggest bug bear is the state of the engine casing, because its just terrible.

Also, when looking over the frame, the rear wheel does not spin freely. In fact, it's a bit tight, and stops as soon as you do. It's this thing to result in a new bearing, and big socket set to get it off? I know that it's been stood a few months, but I always thought the back wheel was a bit stuck.

[megawatt]

You should remove any WD from the inside of the casings with brake cleaner. All the internals should be clinically clean and then oiled with fresh engine oil, then all the gears meshed, gear selector mechanisms stroked several times and all crank bearings lubed.

[fastbob]

You should remove any WD from the inside of the casings with brake cleaner. All the internals should be clinically clean and then oiled with fresh engine oil, then all the gears meshed, gear selector mechanisms stroked several times and all crank bearings lubed.

 

Absolutely right, every moving part should essentially be primed with fresh engine oil . Surely you haven't assembled the engine using nothing but WD40 ?

[leener]

Cleaned outer casing with wd and fresh oil inside. Whole thing has been cleaned and oiled, including inside bearings. Any crap that got in was carefully removed with dry and clean cloth.

I can’t do much more until I get new gaskets.

[fastbob]

Morning, could I thoroughly recommend this excellent engine paint, sticks to anything except a certain brand of aftershave.

[Bender]

Read through most of the updates but confused as to what your doing with regards pistons/rings/bores, sorry if i missed something but if your just putting back together what you took apart there is likely to be little to no improvement in compression ??