siddus74

Jet cat back together ... we sure these bearings for the AMT Mercury are 8x22x7 D608/602 then?

Scott.

Ruizmilton

My Feedback: (29)

Scott:

This is the refernce from where I got the size, they state it's for the AMT netherlands Mercury, you can call them to confirm...
http://www.bocabearings.com/bearing-...ry-hpes-198-lb

siddus74

Ruiz,

Well done ... they say its the electric start ... wonder if they are the same for the Air start?


Scott.

Ruizmilton

My Feedback: (29)

It should be, electric or air start makes no difference on the bearings...

idleup1

If they are the same as amt 180 they are 22x10z6

http://www.bocabearings.com/bearing-...00603C-10x22x6

out of stock. I need a set also.

siddus74

Got the Amt strippped to the point of removing the compressor whell but its on so F****ING tight .... why would it be that tight? I take it that the compressor wheel is screwed on with the left handed thread like the nut? We heated it up and every thing and it wont budge ... it has 2 holes in it on either side of the shalt which we made tool up for with two pegs (we used drills) they kept snaping!

It has got to a point where to holes in the compressor wheel are starting to distort ....

Can any body offer any advice ....


Scott.

Couch Potato

How strange, mine popped off easily with a little warming from a blow torch.

siddus74

Couch ... was it left hand threaded? Was yours a Mercury?

Scott.

Couch Potato

Hi Sid,

It was an early AMT Mercury HP.
I have the old compressor in my hand, the hole is smooth bore, not threaded at all.

I had trouble with the pre-load, it was done with crinkle washers, and the sliding rear bearing holder jammed.
Gummed up thu' lack of use I think.

If you didn't get the compressor hot enough, then if it budged a wee bit it may have picked up and is now stuck like snot to a blanket.

siddus74

Any chance of a picture fella? ... was yours an air start jobbie?

Is your compressor serviceable (git a feeling if I manage to get mine off its going to knacker it)

God Im p***ed off ...

Scott.

Couch Potato

My Merc has now been sold on, no pics of my attempted "butchery".
My compressor has a small nick on the tip of one tall blade, I wouldn't trust it.
I'll take a pic of it later, and if the experts think it looks servicable, you can have it.

I feel you frustration. This turbine is a jewel and really requires the correct tools to work on.
Lathe, special mandrill etc.

And despite best efforts to mark the exact position of compressor and turbine on shaft with a scalpel scratch, never got it balanced properly.

siddus74

I can get it ballanced .... but as I said I think the compressor will be scrapped if I ever manage to get it off ... you say you didnt have to apply much heat on yours ??

Additional : So did you replace the compressor at some point because of the nic? If you did where did you get it from and was it expensive?

Scott.

Couch Potato

My compressor came off with moderate heat.

Compressor was replaced with a new one, supplied from the factory. Along with bits for conversion from air start to (manual) electric start, and bearings etc.

It was not cheap but fair. I'm not sure AMT will supply those sorts of spares now, it was a long time ago.

Robrow

Scott, if your wheel is not coming off its not hot enough.

Rob.

siddus74

Rob

Would putting the assy in the freezer over night then heating the wheel with a torch help me out at all?

Scott

Robrow

I would just use a heat gun, make sure you heat the wheel all over for some time to allow a good heat soak, enough heat and it will come off. Never had one no matter how tight that did not eventually come off...it has to...simple physics.

Rob.

Couch Potato

Sid, here are some pix of my compressor.

Note the nick at 3 o'clock
If you do the same to the blade at 9 o'clock, it might balance.
There will be some loss in efficiency, but it will suck and compress !

Existing balance marks are from factory, not touched by me.

What do you Guys reckon, is this a grenade waiting to go off ?

siddus74

Couch,

Those pictures have explained a couple of things, i wondered why the two holes on the top face of the turbine wheel were different depths and not quite symetrical, they are not for a special tool to wind the turbine wheel off, they are drilled to ballance the wheel!

This of course is backed up by the fact that your wheel clearly shows that the center hole is not threaded and the holes in your top face are not at symeyrical points ... Maybe I should heat the wheel up some more and try and knock the shaft through.

Scott

Ruizmilton

My Feedback: (29)

Siddus:

Have you tried holding the turbine with a crescent wrench (by the hex base, not the turbine nut)and twisting the compressor by grabbing it with a bath towel? That's what I did to pull the compressor off a Pegasus... still you have to be carefull not to damage the compressor blades...

siddus74

Not sure what you mean, we had a wrench in the turbine wheel nut anf heated the compressor then tryed turning it off whilst wearing a welding glove ...

Was your compressor wheel threaded?

Scott

Ruizmilton

My Feedback: (29)

Siddus:

No, my compressor was not threaded, and I do not think yours is..., seems to be stuck hard, I believe the only option would be to continue trying with the heat...

frema

Heat it , and use a press to push it out , but do it carefully , with no damaging the back of the engine.
when you heat it , heat it not to long
you all know aluminium is warmed up very quickly so the shaft will be warm as well ,and you never get the wheel of.
so warm the wheel , you can not hold it with you hands for short time , thats the good temp, and then inmediatly press the shaft.
be carefull with the thread ,use a brass piece of material between the press and the shaft .

Good luck ,

Martin.

frema

Dont tuch the blade.
If you bend it back ,it will brake.
I run with an engine that has two bends, and still runs 250k , without a problem.

siddus74

I cant see the damage? am I being an idiot? How much for it then fella?

Scott

Couch Potato

The blade tip is missing, not bent.
Siddus, PM me your address and I'll post it to you.
If you can PayPal me the postage I will be happy.
I'll PM you when it's gone and advise, won't be much.