New to me Steamer losing coolant

[El Pescador]

So...the new Tiger is losing coolant.  It started to overheat, so I thought maybe the thermostat was stuck since the overflow tank is full, but when I checked the coolant level in the radiator, it was low.  The PO had mentioned it was losing some, so I thought maybe it was a leak somewhere, but I haven't seen any on the garage floor so now I fear it could be more.

I'm concerned it might be a blown head gasket or worse.  The question is, where should I start?  I can't be sure when the last time the oil was changed, so I thought about changing the oil, putting it all back together, running it a couple of miles and seeing if the oil changes to milky color?

Or should I do a compression test now while the tank is off?

Any other suggestions?  Your help is appreciated.

[HeavyHustler]

Check the oil and see if it's milky.

If it isn't then maybe you could do a coolant flush and an oil change.

[Mustang]

compression test NOW!

[El Pescador]

Aye Aye.  Hahaha.  Thanks.

[El Pescador]

Ok...compression test tonight. 120 125 125 on stone cold engine and crappy harbor freight compression tester. What now?   Oh and checked gap while plugs out. They were all good without looking stream cleaned.

[threepot]

Waterpump gskt? or drain bolt washer?  Worth checking everything when engine is running.

[Mustang]

That's good all three are the same .
A little low but we will say it's the gauge.
New oil New coolant ride it.
See what happens................

[JayDub]

Had a blocked header to radiator hose once so the header was in effect isolated from the rad, didn't notice the level dropping over time.

[El Pescador]

If I had a good gauge, what should the compression be?

[ram33]

cant find the compression listed in the manual, but theoretically it should be about 155 psi.
you will lose some due to valves being open for a bit on compression stroke so maybe 135-140?
your valves could be tight which can also lose some.
i wouldn't worry as yours are close together so shows no leaks in hg or cracks

[El Pescador]

Thanks, I couldn't find compression values either.  I'm cleaning carbs and checking valves next.

[El Pescador]

OK...Put everything back together and it ran terribly!  I took it back home, pulled the tank again and it turns out I didn't get #2 cylinder plugged in with good connection.

I checked the oil at the time.  It didn't have a cappucino color, so I'm confident there isn't coolant in the oil.

Next...I decided while I have the tank off I might as well clean the carbs and check valve clearances.  I don't think this has ever been done BTW.

So I have a few out of spec

two exhaust at .23 and one at .25  the rest are either .2 or .15


The real question is...Number 1&2 cylinder intake are within spec 3@.15 and 1@.13  but number 3 cylinder is WAY off... .06 and .04 (double checked).  As you can tell, I'm a total noob at this so I don't know how unusual that is, but for it to be so different from the others is concerning.  It is only 1 to 2 shim sizes?

As always, your help is greatly appreciated.

[ram33]

it could be the valve recessing into the head
change for the correct shims and do another check in a few 1000 miles and see if its changed a lot again
you can get the same shims cheaper elsewhere as many different brands use same shims

[threepot]

The thinnest shim you can use is 2.025.Measure the shim in already,and Just use the chart in the manual to calculate the replacement shims. Its not uncommon for the inlets to close. I've just finished them on my Super3. All the inlets were out..4 had negative clearances! 2 of those were the thinnest shims! Ive cheated to avoid taking the head off and replacing all the valves. Ive ground the relative amount off the top of the valve. Its a time consuming job,but I managed it. New cam chain,guides and plugs..bike fired 1st time.

[Mustang]

@    El Pescador ,
that is totally a common occurrence on a steamer .

the only ones I would change shims on are the two intakes on #3 . get them up to at least .10 mm , personally I'd go for the high side at .15
and don't worry about it , you'll be good for 10 k miles at least b4 you need to check them again .
Unless you flog the dog at 7500 rpm all day long on the interstate ......