Renamed, Head Gasket Leak, Solved

vtrtomuk

after research and reading on many car forums iv decided to go with a copper head gasket with a bit of hylomar universal blue and a re skim on the head... depending on what the engineer says will double up the base gaskets. hopefully that will be the last time i hear of a leak.

with the help of the new thermostat as well

will probably take some pictures when putting it back together wont be till around the 20th of this month though

vtrtomuk

UPDATE,

had the head checked by a engineer buddy and its all flat so no warpage.

the workshops theroy for the blown head gasket.

in normal operation the thermostat regulates and pressurizes the system as @Calum stated maintaining a optimal temperature,

without a thermostat and having a free flow the "cold" coolant from the rad is being dumped into a boiling hot engine causing " thermometric" stress over time you end up with unevenly cooled parts of the head and develop hot spots "most likely over the exhaust port" this causes the aluminum to expand quicker than other parts and essentially crush the head gasket in small places. basically a slight bulge in the head surface. the engine then cools and the aluminum in the head then returns to normal, unfortunately the gasket cannot, so when you next start the engine from cold the gasket then blows past the weakest point your crushed head gasket !

i relise @Calum you have said this earlier doesn't hurt for a second opinion. but thank you i wouldn't have chased the thermostat route if you hadn't have clocked on to it

well parts should be here tomorrow including a new THERMOSTAT! so fingers crossed

cheers lads

Calum

Yeah sure mate. I do a fair bit of reading. I didn't appreciate the importance of the thermostat until I read it possibly 6 months ago. I always ran with one.but didn't know why until quite recently. What he said is true, but I doubt the head will be cold, the hot stale pockets are what I have read time and time again.

I'm sure he's right though.

vtrtomuk

http://i44.photobucket.com/albums/f21/tom_smith7/IMG-20160412-WA0001_zpsrdcpssxh.jpg

So i got all my bits and have all been fitted. went for a 40 mile ride last night no leaks and no need to top up coolant,

on the way to work today 30 mile trip let bike cool coolant is just under rad neck so possibly just working out air bubbles so probs lost 5-10ml

this is using the copper gasket with copper sealant "spray a gasket" type of stuff

see how it goes on the ride home

vtrtomuk

Update,

went to go get a maccy d's for lunch lost a bit of coolant, so im afarid its still not done anyway got a second head now so ill go get that skimmed and the barrel checked, why are these such a bast**d to seal done x amount of 2 stroke head gaskets never had a leak., yet the dt is a pain. so im just going to go on the assumption that things are warped somewhere, at least i got a geunuine head gasket floating around now. the head gasket should show where the leak is hiding .

i think its safe to say yamaha should have used O rings instead of steel gaskets like all there other 2 strokes, funny that iv never seen a AM6 or a rotax 122 (not yammys obv) head gasket leak there both oring'ed, i feel a experimental project comming on

has anyone done it before ?

Calum

@tomimsmith1992 Yes actually have seen it before. Although you still need to seal against the rest of the faces.

I a, surprised you are having so much trouble. I had one head gasket go on a cheap head gasket. And if you have seen my belgarda build then you know I have dealt with rough engines lol

You had the barrel skimmed as well?

vtrtomuk

well im actually debating weather im just panicking,

head and barrel skimmed and copper gasket with copper seal torqued to 22nm. the water has dropped in the rad to what i filled it up to, water is just sitting below the rad neck, and don't seem to be losing anything more, that's probably just where the water level is set.

like i said im probably just being a idiot and lacking faith lol. i'll see how it goes for a week and keep an eye on it,

Calum

@tomimsmith1992 You would expect it to drop a little once it's bled etc.

See how you get on.

vtrtomuk

just out of curiosity where does the water level usually settle? pictures welcome

Darty

@tomimsmith1992 You can expect the water level to drop over time, if it's always above the top of the core you should be fine. Mine usually settles about 5mm below the neck and is good for over 800 miles or more untouched.

https://farm2.staticflickr.com/1680/26399968226_8339ed7d30_z.jpg

https://farm2.staticflickr.com/1528/26333536622_d52b506a06_z.jpg

vtrtomuk

Cheers @Darty perfect just what i was looking for !

vtrtomuk

Update, All is good ! looks like its fixed for now !

can someone remind me noise from clutch in neutral but when you pull the lever the noise goes ?

can't remember what it is the cause ?

Calum

Clutch needs to be balanced properly if it's dismantled.

But But noise is generic. Is it metal on metal sound?

DT125R FORUM

Renamed, Head Gasket Leak, Solved