Thermostat housing leak

[mattster31]

Been absent from this place for quite some time.....:-( Work just seems to always get in the way....that and we bought a travel trailer.....but I digress.

So I started it up the beast the other day (after it sat for over two months....long winter) and I noticed steam rising from around the tank. It smelled like coolant. So after pulling the tank, cowling, rad, pushing wiring out of the way etc......I discover the leak to be eminating from the thermostat housing proximal to the radiator. Of all the places to get a leak it had to be there :-( I am hoping its just the seal but I noticed the small 90 degree nipple that protrudes from the housing cover (clutch side) was also wet around it. That piece is only replaceable with the housing cover. Perhaps I should replace that part as well as a new thermostat? Has anyone experienced a leak in this location? Thanks in advance!!

Mattster

 

[Canadian FJR]

That sucks. Did you do any work to it over the winter or did the seals just dry out from sitting all winter?

Canadian FJR

 

[mattster31]

Haven't touched a thing on it since I yanked the engine out two years ago for the valve shims (with the exception of oil changes)

Just get on and ride...........neglect is a vengeful ***** :-()

Probably had it coming...............

 

[JamesK]

I had a small leak develop in that same area at around 130k miles. Replacing the thermostat (which has a built-in gasket) did totally fixed the leak.

You can do the job by just removing the lower cowl, that will give you sufficient flex room to get at the area without having to pull of the upper cowl.

 

[Canadian FJR]

Where exactly is this thermostat that you speak of ?

Canadian FJR

 

[JamesK]

Where exactly is this thermostat that you speak of ?
Canadian FJR

It's right next (before when siting on the bike) the glove box on the LHS. The thermostat housing is just below the radiator cap.

 

[SkooterG]

Where exactly is this thermostat that you speak of ?
Canadian FJR

It's right next (before when siting on the bike) the glove box on the LHS. The thermostat housing is just below the radiator cap.

On a Gen II. Location on a Gen I is completely different.

Mattster31 - my first 04 FJR developed a slow leak at 95,000 miles right after a crash interestingly enough. Turns out it was the thermostat - or actually the rubber seal that is part of the thermostat. A new thermostat took care of my leak. From your description I don't know what the heck you are talking about. But if it is a leak coming from the T-stat housing I would first suspect the thermostat seal.

Edit: Here's an old thread on the subject of my leak. I have some photos at the bottom of page 2: https://www.fjrforum.com/forum//index.php/topic/19677-coolant-leak-at-the-thermostat-housing/

 

[mattster31]

Thanks Scooter, and yes, the GENII and Gen I's are in totally different spots. I wish mine was just under the rad cap. I read the post on your leak shortly after posting myself. I've got it in the same spot you had. Right along the seam of the housing. Only way I could actually see it was through a mirror angled just right as it was on the forward side towards the rad, but In order to be sure I pulled the radiator off and it was confirmed. Although, in pulling the rad off I noticed it very wet along the bottom corner of the right side manifold, so I'm going to take it to a rad shop for pressure testing to be safe. Could have just been from the leak but I hadn't ridden it yet and it wasn't leaking at the end of last year....I think. I'll see what a re-core costs but I'm guessing it will be at least the same as the cost of a new one ($345)........but then I have to wait till the end of the month when I take a trip down south, because the prices up here are ridiculous.