Weird overheating issue, intermittent

[tntmo]

So I found out that a brass fitting will fit.  Got one at the local Home Depot for less than $2



Fits just fine. 



Now, hopefully it won't be spewing coolant on the dash anymore.  But if it does continue to overheat, I'll look into the thermostat next. 

[Chris Canning]

Which brings us full circle because some time back Metalguru did a thread on such a brass fitting and we cannot such in the Uk,he got his from Canada.

I knew when we were in Carlsbad in January there was something I mean't to buy and just couldn't remember bit of a hike to go back!!

[tntmo]

Ok, so the bike has been acting up a bit over the last week or so.  It stays cool for a day or two, then on the way home from work it will creep toward the red and maybe put out a bit of coolant or steam from the overflow, which works good now that I have the brass elbow.  Anyway, I was on a back country ride today and it crept toward the hot side about 50 miles into the ride.  It stayed down below the red, but just a bit below.  The engine never felt hot, and it would even cool down a bit when I stopped and let it idle and then crept towards the hot side as I got back on the road.

Stopped for lunch, let it cool down.  On the way home, it started to get hot again, and then pushed into the red.  I pulled off the highway and steam was coming out from under the tank.  I kept the bike idling and it cooled off to below the middle of the temp gauge.  I was less than ten miles from home, so decided to try to get home. 

It would heat up to just below the red, spewing steam from under the tank and then it would cool down and quit steaming everywhere.  Made it home just fine and pulled the tank off after it cooled off. 

Here's what I found.  Hole in the thermostat housing, and the rest of it was not in good shape either.











The thermostat shouldn't look like that, pretty sure?! 



Never had this apart before, but I believe this is supposed to be a guide for the thermostat.  It's all messed up inside.



Also found this piece of metal in the thermostat housing.  WTF?

[Mustang]

well on the plus side you at least found the problem ...........

[tntmo]

I'm hoping this is what has been causing the overheating issues.  Maybe the thermostat has been getting jammed up in there?

Anyway, I got lucky and snagged a thermostat housing on Ebay for $45 shipped.  Hoping for the best. 

[Sin_Tiger]

Don't want to be the dour  Scot again but I'd suggest having a look inside your water pump and a good flush with decent pressure hose in the reverse flow direction.

[tntmo]

For sure, that is planned before running this thing up again. 

Don't want to be the dour  Scot again but I'd suggest having a look inside your water pump and a good flush with decent pressure hose in the reverse flow direction.

[Sin_Tiger]

Giffard you found it though 

[tntmo]

Changed out the thermostat housing and thermostat with used parts I got from Ebay.  Bled the system out fairly well, at least I think so.  Last night I got it all finished up and took the Tiger out for a ride, did about 25 miles and it stayed nice and cool.  I figured my issues were behind me.

This morning I got started on a ride out to the mountains.  It was doing just fine until about 15 miles into the ride where it spiked up to just below the red and started bubbling out of the overflow tank all over the side of the tank, the dash and it was  blowing out the hose in front of the rear tire.   I pulled over and let it cool off a bit, wiped everything up.

On the way home, it would quickly heat up to about 3/4 on the gauge and steam was coming from the overflow tank.  When I would stop for a bit, I could hear it bubbling in the overflow.  It would get hotter on the highway, cool down at stop lights a bit and heat up as I would go faster. 

So now I'm back to square one.  It runs cool on one ride, then gets hot on the next. Runs hot on the highway, but stays cooler in town. I just don't know...

Untitled by tntmo2, on Flickr

Untitled by tntmo2, on Flickr

Untitled by tntmo2, on Flickr

[Bixxer Bob]

If you are sure you bled it properly and had no air pockets, I'd be looking closely at the water pump again.  Is the drive to the impeller ok?  It sounds like the pump isn't working all the time. I know that's a long shot, but when you eliminate the likely, you have to deal with what's left.  I think Sherlock Homes said that.

The imtermittent feature of this fault is leaning me away from head gasket at this stage, but a compression check wouldn't do any harm.

Edit: just read your post again, are you sure the Ebay stat is working properly?  A new one isn't that expensive......

[tntmo]

I am going to try to bleed the system again and see what happens. 

I pulled the water pump cover to check that out, I didn't see anything unusual. 

Thermostat would be my first thought as well, just find it funny that it's acting the same as before.

Would head gasket be intermittent like this?  I'd think it would be all the time.

If you are sure you bled it properly and had no air pockets, I'd be looking closely at the water pump again.  Is the drive to the impeller ok?  It sounds like the pump isn't working all the time. I know that's a long shot, but when you eliminate the likely, you have to deal with what's left.  I think Sherlock Homes said that.

The imtermittent feature of this fault is leaning me away from head gasket at this stage, but a compression check wouldn't do any harm.

Edit: just read your post again, are you sure the Ebay stat is working properly?  A new one isn't that expensive......

[Bixxer Bob]

I don't think head gasket would be intermittent, hence me saying I'm leaning away from that for now, but at the same time if it's not the obvious.......

Stats sometimes get lazy and are slow to open, but it still sounds as though yours is sticking, or the pump is.  I thought the stuff you found in yours worrying and it could be another piece of junk has made its way round to the stat or pump.  You'll know when you strip it.  And I'd still like to know what it was originally, or where it came from.....

Test the stat in a pan of cold water then heat the water up.  The stat shoukd open at the temp stamped on it.

[tntmo]

Ah, yes...I see you said that earlier about the head gasket.  At this point, I'd love to just know what it is so I can get it repaired and enjoy my Tiger! 

Well, I pulled the tank off and checked it all out again.  Pulled the radiator and ran a bit of water through it, seems to be flowing well.  Here's what the repair looks like, not pretty but don't think that should cause these issues.

Untitled by tntmo2, on Flickr

I pulled the water pump out, everything looks ok there.  I removed it completely, the drive spline on the back is fine and is engaging into the engine.

Untitled by tntmo2, on Flickr

Then I pulled the radiator cap and found this again.  The thermostat housing is getting messed up!  This was a used Ebay part, but was in nice shape when I installed it.  Now, is the thermostat failing and causing this to break down, or is this from something else?

Untitled by tntmo2, on Flickr

I don't think head gasket would be intermittent, hence me saying I'm leaning away from that for now, but at the same time if it's not the obvious.......

Stats sometimes get lazy and are slow to open, but it still sounds as though yours is sticking, or the pump is.  I thought the stuff you found in yours worrying and it could be another piece of junk has made its way round to the stat or pump.  You'll know when you strip it.  And I'd still like to know what it was originally, or where it came from.....

Test the stat in a pan of cold water then heat the water up.  The stat shoukd open at the temp stamped on it.

[Chris Canning]

Is the engine oil clear?

[Bixxer Bob]

I can follow Chris's thinking, that looks oily.  Is it oily?

Also, was that lip broken when you fitted it or has it just happened?