WHAT WOULD YOU DO NOW

[roblc350]

YPVS 31K CYLINDER HEAD
Engine was in the frame
connected up the rad & pipework & filled with water
water pissing out..Checked head bolts all were tight
Engine taken out / head off / Head gasket looks new ( as this was surposed to be a rebuilt engine )
After reading some threads on here & talking to yogi
brought some high temp silicone
losened the base / barrel nuts to finger tight
head face placed on pane of glass / no signs of any wrarpage 
silicone applied to head 
Torqued in sequence in 2 stages to final 22lb & tightened the base nuts
Connected rad up on bench / filled with water
Now Got Small constant WEEP 

WHAT WOULD YOU DO NOW  ??

Thanks ALL

[midlifecrisisrd]

Did you apply sealant to the barrel side of the gasket?

Steve

[roblc350]

Hi Steve
as per the instrutions on the silicone
apply to one surface only ?
so i applied it to the head side

[veg]

Rebuilt? By whom? Says who? When? Receipts?

[stusco]

Jul 28, 2020 16:18:01 GMT 1 roblc350 said:

Hi Steve
as per the instrutions on the silicone
apply to one surface only ?
so i applied it to the head side

This would only apply if there wasn’t a gasket 

[roblc350]

as i said veg
surposed to of been rebuilt
who said....the guy i brought it from
by who...a engine builder / mechanic mate of his
reciepts for parts fitted .... No
Photos of rebuild...yes

Now back to the problem

[veg]

So no comeback then? That’s what I was angling at. Eg builder of repute?

[roblc350]

No comeback...correct
builder of repute...well i dont know him

[jon]

I usually heat cycle a few time before putting any water in on a freshly installed gasket.

Jon

[tony2stroke]

Get the head pressure tested, Check gaskets on bottom of barrels are clean, put a metal ruler (sideways) across the barrels once they are tightened down on engine, to check 1 is not higher than the other, I would do this first.

[roblc350]

i will try the metal ruler tip first as the head is off
the base gaskets are new
if above is good
i shall apply silicone to both faces ( below & above the gasket and try again
if that fails i shall replace the head or get it skimmed / refaced
unless someone else has any other ideas

Cheers

[stusco]

If your putting sealant on any gasket it needs to be on both sides of the gasket

[midlifecrisisrd]

I also worry about between the layers when reusing a head gasket

Pity I'm bot at home, I'd have sent you a new pattern head gasket foc

Sure I have one somewhere

Steve

[roblc350]

Cheers Steve
going to try what i said above tomorrow

[4l04ever]

Where was the water leaking from? Was it the same place after attempting repairs?

[Shytalk]

Jul 28, 2020 22:08:42 GMT 1 4l04ever said:

Where was the water leaking from? Was it the same place after attempting repairs?

Yes, my thought as well, where is it leaking from? any pictures of it that you can post up?

[earthman]

Jul 28, 2020 18:02:46 GMT 1 jon said:

I usually heat cycle a few time before putting any water in on a freshly installed gasket.

Jon

Interesting, I never would have thought of doing that on any water cooled engine,..how long does it take for the temp gauge to go up then?
I'm guessing that you are just running the engine whilst in the garage rather than on the road??

[chrisg]

Jul 29, 2020 11:31:33 GMT 1 earthman said:

Jul 28, 2020 18:02:46 GMT 1 jon said:

I usually heat cycle a few time before putting any water in on a freshly installed gasket.

Jon

Interesting, I never would have thought of doing that on any water cooled engine,..how long does it take for the temp gauge to go up then?
I'm guessing that you are just running the engine whilst in the garage rather than on the road??

I’m guessing that because the gauge isn’t in water, it will not read any temperature. I’m guessing it’s run for a couple of minutes?
As you say, interesting 🤔

[roblc350]

Update
Originally the leak was just down one side ( that was before I done anything)
Also checked across the barrels with a metal ruler. & all ok there
After applying silicone to just one side Of the head the leak was just towards the front corner
Today siliconed both sides
Head toqued down once again
Going to let it cure overnight
Can’t run the engine just yet as Dave the carb master has them
So can check tomorrow on the bench to see if it’s now sorted or wait and run it up for a short time before adding water
Think I’d rather know now if it’s sorted or not so will check tomorrow & if not get the head refaced
Cheers

[tony2stroke]

Head bolts and washers can cause some issues if not in good condition, if washers are bent or distorted they can alter the torque setting, also if the threads are not clean on the bolts or studs it can do the same, they should all tighten up with your fingers at same pressure until you start torquing them up, if you feel resistance there something wrong, always use some oil on the studs before torquing down and make sure everything is lubed up, dirt can also alter settings, if you hear any grinding when doing up bolts there is most likely some crud in there somewhere.

[Tobyjugs]

Have you checked the height of both barrels? Base gasket landing face to cylinder head landing face.

[flames]

I had same problem with mine leaking out of gasket on front corner area on l/h cylinder a while ago. Went through 3 gaskets ( fibre variety ) but had had them a while and eventually put it down to them losing the stickiness if that is the right term. I ended up getting a gen yam gasket and it seemed to cure it. I have removed the motor now and have noticed my barrels look to be sitting at slightly different heights. Not sure if barrels may not be a matched pair but maybe the cause of original leak. Perhaps the gen gasket just did a better job of sealing but may also of hidden an issue I didn't know I had.