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Discussion Starter #1
Hey guys need some help here.

First let me ask this:

What else besides these three things can cause water in the cylinder?
1) Cracked head (or hole)
2) Bad head gasket
3) Bad cylinder


I picked up a 1985 6000 El Tigre. Hadn't ran in years. Gas looked like coffee and smelled like turpentine.
Radiator was empty, but didn't think anything of it as it sat for so long.
Didn't have spark, but the key switch was broken.
Fixed that and pulled her over with the plugs out to check for spark.

(I should say there was some goo-ey stuff on the plugs, but I figured someone put oil in the cylinders before parking it.)

Whole bunch of crap came out of one side. I dunno
looked around couldn't see anything. came back 5 minutes later and
pulled her over and a LOT of crap came out of the cylinder.
Noticed radiator was going down, but hoped it was just air trapped.
Put a little gas in the "dry" side and pulled it over with the other plug out.
Almost started, not much flew out of the cylinder this time.
So I put some gas in both sides, plugs in, and gave it a rip.

Can you say volcano??
I got an anti freeze shower as I had the radiator cap off. :Bangin:
Pulled the engine and I found a few things, but nothing obvious.
Head gaskets looked OK, but it was getting dark.
"wet" cylinder had been enscribed with a number two and arrows
pointing for direction. Rings look good, skirts are good, could not see
any obvious problem.
 

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Almost sounds like a blown head gasket. If you get pressure in the cooling system right after starting a cold engine its compression pushing the liquid out. I have an 84 el tigre 6000 and I blew a head gasket and the coolant would gush out just after starting cold.
 

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Discussion Starter #3
oops, hit send instead of preview.....

I haven't pulled the cylinders yet but I got a lot of numbers.
I'm curious if someone already replaced a cylinder.
The entire motor came out and apart as if it had been done many times before.
Nothing was over tight, everything came right off.

I should say it's got some Arctic cat racing decals and paint.
Never seen them before, but I'm no expert.
It also only has 2400 miles on it.

Anyway here are some numbers if anyone can affirm that things are original or not.

Chassis: mfg 9/84 vin 8502406
Spirit AH50L5 0662-004 engine decal on water pump housing. Correct
500cc pre mix, dual fuel pump, twin vacuum ports.
Engine Lower case: H50-500916 on long side.
Engine Lower case: SCEM 500cc Made in Japan.

Head casting No.: 92/540 E1
Mag side cylinder: has 1220 stamped on side at base.
has 81E7 stamped on front of base.
Clutch side cylinder: has 9LH8 stamped on front of base.

Carbs are mikuni and are stamped W4 / 74
anyone know if these are 38mm or 40mm?

According to Browns and other sites information,
I have no idea what is unique about the 85 crank case.
But the same head fits 80,81,84,85 500 pre-mix.
Same with the cylinders.
However the cases for these engines as well as the 78,79 440's
and the 77 340's all used the same case halves.
Was the 85 the only one with dual pump ports?

Sorry for the novel guys,
any feedback is appreciated.
 

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Discussion Starter #4
It's been too cold to get back at this.
I've been trying to find a listing for cylinder casting numbers.

It just doesn't make sense that one would be 81E7 and the other 9LH8. Doesn't the 8 & 9 indicate the year of build?
I'm thinking one was replaced earlier.

Anyway if someone has one of these engines, would you mind
checking your cylinders for casting numbers.
Thanks.
 

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Way back when I had a 76 Rupp Magnum that would blow water. It ended up being a stripped head bolt. Cylinder pressurized the cooling system and boiled it over.
 

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Discussion Starter #6
Thanks Pol-Cats,

I looked at it a little more today.
All the through holes in the head are dry and kind of crusty white as to be expected.
All the dead end holes in the cylinders are dry except for two,
but that could be from me spilling as I pulled the head off.

Just curious what the results would be if someone put 440 gaskets onto a 500 motor?
I realize the 2mm difference between the two would be hard to catch at a glance.

This late in the season, I'm tempted to put new gaskets in.
Then bolt it down to my bench with a two liter bottle gravity feeding coolant to the head and see what happens.

It would either still pull coolant in if it wasn't a leaky gasket,
or it wouldn't do anything if it was.
Beats stuffing it all the way back in.
 

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I think you would need a closed system to find out. What I would do is put it back together, seal up the water ports and some home do a "leak down" test like we do for crank case leaks. Not sure what psi to use though.
 

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Discussion Starter #8
I pulled the jugs off.
It's looking like this was a problem for a long time, and someone gave up and let it sit.
There is a lot of scale rust where the front shocks bolt in, from water sitting. Most likely from coolant being pumped out the exhaust.
There is evidence of the muffler filling with coolant as well.

The rings are froze on both pistons. One dark from ignition, one washed clean. Same with the head. the reed stopper on one was all cruddy like the inside of a radiator.

I still don't see any major fail. There is no rust on the crank. (amazing) Washed the case out with gas and diesel.
It spins free and even. Makes some noise when dry, but un-sealed bearings do that.
Blew it out and then filled it with oil. Rods have some play in them,
not sure how much this engine normally has. It looks like there is a needle bearing at rod base rather than a solid.
No evidence yet of oil seepage from the area where the one bolt threads popped the case bossing. I think it is OK. I'm sure trying to take it out would be worse than leaving it alone.

Head gaskets are 500 (70mm). Usually you can see a fail point if there is a leak. Especially if severe. Going to check the head for straightness.
Cylinders show signs of honing. I don't know what plated ones look like new, so I can't tell if too much was done.
At least there are no major scratches from the frozen rings.

As always, thanks for your thoughts.
gg
 

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Have you checked the head for warpage ?

I've read in a few places that some of the gasket sets head gaskets do not seal correctly.

Mike
 

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Discussion Starter #11
Looking closer today it looks like there is a gouge in the head from a previous tear down.
Might be it, I'll try and clean it up.
Anyone know what an untouched cylinder should look like?
These have been honed somewhat, but I have no idea if it was done too much.
Or what the max over bore is without having to have them re-plated?
 

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Looking closer today it looks like there is a gouge in the head from a previous tear down.
Might be it, I'll try and clean it up.
Anyone know what an untouched cylinder should look like?
These have been honed somewhat, but I have no idea if it was done too much.
Or what the max over bore is without having to have them re-plated?

As far as the head lay it on a piece of glass and see how flat it is with a feeler gauge. You can clean the head up by taping some 400 grit wet and dry to the glass.

nikasil is pretty tough, you can see it coming off/ wearing thin normally around the ports.
 

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Discussion Starter #13
Making time for this when I can.

The top edge of one cylinder is gone.
I mean it looks evenly rounded all the way around as if it was done on purpose only in the process the surface area for the metal gasket ring was cut in half.
One side of the head shows a great deal of pitting from pre-ignition.
Most likely due to someone drilling out the airbox with a spade bit.
If I can't find a used one, it looks like welding and a re-grind.

I still think someone raced this thing at some point.
It has custom hand painted "arctic cat racing" striping and emblems.
The sled must have landed extremely hard on the front end.
On one side every single bolt was snapped. Both A arms, sway bar, and shock bolt.
On the other side, one rod end stripped out and the spindle arm where the tie rod bolts on was twisted 180° from the ski being pushed in.
Amazingly the tunnel, pan, and front engine box all look straight.

Anyone ever seen that much damage on this style suspension?
 
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