WR450F - HGF or something else?

[-Cappo-]

I decided to list my elderly WR450 on eBay, as I never use it and probably won’t in future. It’s a very well-used 2004, which I listed at £0.99 no reserve, and it has bid up to £1400-ish which I’d be happy with. However….

I took it for a new MOT yesterday (passed with 0 advisories) but on the way home, about 9 miles, it boiled over about 200 yds from my house. I left it overnight, then put some coolant in this morning. Started it without the cap to check circulation, and this was the result:


https://youtube.com/shorts/p2ooHzXgMlM?is=tghLw5yr...

(Can’t get that to embed as a video here).

I’m assuming that’s head gasket failure? Just wondered whether anyone could confirm or provide an alternative diagnosis. I guess I’ll be cancelling the listing then while I decide what to do with it.

[Steve Bass]

-Cappo- said:

I decided to list my elderly WR450 on eBay, as I never use it and probably won t in future. It s a very well-used 2004, which I listed at £0.99 no reserve, and it has bid up to £1400-ish which I d be happy with. However .

I took it for a new MOT yesterday (passed with 0 advisories) but on the way home, about 9 miles, it boiled over about 200 yds from my house. I left it overnight, then put some coolant in this morning. Started it without the cap to check circulation, and this was the result:


https://youtube.com/shorts/p2ooHzXgMlM?is=tghLw5yr...

(Can t get that to embed as a video here).

I m assuming that s head gasket failure? Just wondered whether anyone could confirm or provide an alternative diagnosis. I guess I ll be cancelling the listing then while I decide what to do with it.

Perhaps a compression/leakdown test will confirm. Also see if the engine oil is showing signs of coolant contamination.
You might have a water pump issue with an impeller failure or such.
Fingers crossed it's the water pump but that failure might have exacerbated the head gasket...

[-Cappo-]

Steve Bass said:

Perhaps a compression/leakdown test will confirm. Also see if the engine oil is showing signs of coolant contamination.
You might have a water pump issue with an impeller failure or such.
Fingers crossed it's the water pump but that failure might have exacerbated the head gasket...

I’ll try a compression test. It seemed to be running fine yesterday, no obvious loss of power. I did consider the water pump, but I can’t think what else would be firing coolant out so forcibly other than compression (plus, starting from stone cold, what was coming out was steaming within a few seconds so something is superheating it!)

[Steve Bass]

If that's from stone cold then yeah, you might be looking at the head gasket.

[-Cappo-]

Just have to decide whether I can be bothered pulling it apart, or whether it goes back on eBay for spares/repair! It’s not worth a lot of money even if it’s running properly. I’ve had the top end apart in the past, to replace piston/rings, but I don’t enjoy doing that sort of stuff any more and it’s just a time drain.

[Steve Bass]

If you're taking the top off, it's probably going to need the head skimmed, gaskets, chain guides etc. Maybe better to sell as is and let someone else take the hassle.

[-Cappo-]

Steve Bass said:

If you're taking the top off, it's probably going to need the head skimmed, gaskets, chain guides etc. Maybe better to sell as is and let someone else take the hassle.

Yeah I think so too, thanks Steve.

[Jap90s]

It's hard to find a cheap dirt bike

I'd list it as a classified ad for 30 days at £1495 and see what happens, I think you'll sell it for near that