Timing Chest Gasket Removal & Tensioner Life

[n3303j]

Now that they've taken the Methelyne Cloride out of Aircraft Paint Remover what will remove this aged on gasket?

[lucian]

CRC makes a spray remover. I've had some success with acetone and patience.
https://www.ebay.com/itm/284973871851?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A1bZJUpUWIQmyJG2d5tZwYdg41&norover=1&mkevt=1&mkrid=711-117182-37290-

[guzzisteve]

I used bug hydrator made by Motul, worked better than anything ever. I was amazed.

[Antietam Classic Cycle]

"Aircraft Remover" from Rustoleum works pretty well. May require multiple applications.

Heating the gasket with a heat gun to soften it eases removal as well. 

[Stevex]

Stanley knife blade...with care.

[n3303j]

Gasket stayed with crankcase.
Engine is in the frame.
Gasket surface is vertical.
Not the easiest place for hand scraping.

[Huzo]

If it’s of any use, I have had mine off a few times and just re used the metal gasket after spraying it with copper spray.
Zero leaks.

[80CX100]

After cleaning up a few plain fibre gasket messes on the valve covers, I try to coat the engine side of any new gaskets with a little grease and use metal core Valpolinis if possible.

For scraping tools the big plastic bread bag type closer thingies that come on big bags of turnips,beets, etc are very handy with no fear of damage.

I've also got a neat little tool that is intended for scraping/cleaning glass, uses exacto type blades.

At times I've used rubbing alcohol or WD40 to help clean final sticky bits, just because it's what I have close at hand.

fwiw

[n3303j]

Guess I was just hoping someone knew of a stripper that still contained Methelyne Chloride. That seems to be the magic ingredient. It was never officially banned, but was a matter of discussion 5 years ago. Guess everyone panicked and got it out of their products before they became the next "Roundup" (Talc, Camp Lejeune, etc).

I threw out my last can of Aircraft Stripper after the contents ate their way through the can. It was serious stuff. Usually the cans would collapse and then start leaking product.

Meanwhile I can buy pure Methelyne Chloride mail order. Go figure.

[Cam3512]

Dude, it’s pretty much a paper gasket.  Don’t let it beat you.

[n3303j]

DONE: Razor blade & sanding block. 2 hours lying on the floor.

Acetylene torch didn't phase it.
Swear it's Asbestos.
Torch didn't even mark it.

Old gasket was green stuff.

New gasket was charcoal gray.

We'll see what happens if I ever have to go in the timing chest again.

From our FWIW department:
The blade tensioner had 80,000 miles on it.





The side plates wore grooves 0.050" deep in the blade
The rollers wore 0.035" off the blade surface.



It would not have gone another 80K miles and still function.

The timing chain showed no visual signs of elongation. (111,538 Miles)
The driving (crank) sprocket looked almost unworn.
Either of those parts probably would have gone another 100K miles.
I replaced them while I was on the neighborhood.

[Huzo]

DONE: Razor blade & sanding block. 2 hours lying on the floor.

Acetylene torch didn't phase it.
Swear it's Asbestos.
Torch didn't even mark it.

Old gasket was green stuff.

New gasket was charcoal gray.

We'll see what happens if I ever have to go in the timing chest again.

From our FWIW department:
The blade tensioner had 80,000 miles on it.





The side plates wore grooves 0.050" deep in the blade
The rollers wore 0.035" off the blade surface.



It would not have gone another 80K miles and still function.

The timing chain showed no visual signs of elongation. (111,538 Miles)
The driving (crank) sprocket looked almost unworn.
Either of those parts probably would have gone another 100K miles.
I replaced them while I was on the neighborhood.

Jeez that’s a long way gone, you did well attending to it….

What bike is it ?

[fotoguzzi]

That’s the aftermarket blade tensioner? Looks like it did the job.

[n3303j]

That’s the aftermarket blade tensioner? Looks like it did the job.

Bike is '77 850-T3.
I put tensioner in at 30K miles.
Removed at 111,538 Miles.
I'm assuming wear rate dropped when the chain rollers were also pressing on the blade.
Suspect service life is around 100K miles.
Glad there's an oil filter to catch the powdered plastic.

There's one gear each side of the driver (crank).
The driven cam is contributing to the slack in the chain.
The driven oil pump is actually using the tensioner as sort of an idler.
The drag from the pump tries to straighten out the slack side of the chain.
This increases pressure on the tensioner shoe.
Wonder how much torque is required to run the oil pump at rated pressure?

[Huzo]

This increases pressure on the tensioner shoe.
Wonder how much torque is required to run the oil pump at rated pressure?

Dunno, but I’m not a big fan of the amount of load the large tensioner places on the oil pump bearings.
Mine is coming out when I get it home and these are going in permanently.

[fotoguzzi]

 

Dunno, but I’m not a big fan of the amount of load the large tensioner places on the oil pump bearings.
Mine is coming out when I get it home and these are going in permanently.

[Huzo]

Yeah.
I had them in once before, but began to doubt whether there was enough lash…(there seemed to be zero) and the thought of them expanding was too much to contemplate.
Roper (and others) assure me that the aluminium cases expand vertically with temperature and this opens up the clearance.
That makes sense to me.

[n3303j]

Dunno, but I’m not a big fan of the amount of load the large tensioner places on the oil pump bearings.
Mine is coming out when I get it home and these are going in permanently.

Oil pump shaft is running on double ball bearings.
Not worried about the radial load on that shaft.
100K so far with little wear so it will outlast me (Age 78).
Interesting to see if your straight cut timing gears whine louder than my plastic chain tensioner resting on the case wall?

[Huzo]

Mine has done 200,000 and not broken, so that’s not an issue.
The bearings do have some play, but I have a new oil pump. The gears will make more sound initially, but I’m told they bed in quite quickly and settle down.
I just like the idea more.

[Huzo]

The only section of chain not under tension during operation, is the run between the crank/oil pump sprocket.


Clearly there’s no room, but that’s where the slack should be taken up ideally.
I do agree that the torque required to spin the pump under operational conditions is probably relatively light, but having the tensioner where it is, is not what you’d do if you were able to avoid it.
They work and they last, but it is not ideal.