jack the front of the car up as much as you can. stick some jack stands under it just incase. start run till operating temp with heater on.

 

all the bubbles will rise out the radiator and maybe solve your problem.

 

if you can get lower temp thermostat get it. if they don't can you drill a couple 4mm holes into it? or is that tooo dodgy?

the radiator isn't the forward most part of the cooling system, there are heater hoses an lpg converter (being deleted before car is back together) and possibly the heater core in front or higher than the radiator..... maybe I need to bleed the heater core?

 

drilling holes in the thermostat doesn't change the operating temperature of the cooling system, just makes it much much slower to get to operating temperature.

 

I can buy (or should be able to as they are listed in the tridon catalog) thermostats in a large number of different temperatures to suit this application too, so 5 degrees cooler it is!

 

Robert.

the radiator isn't the forward most part of the cooling system, there are heater hoses an lpg converter (being deleted before car is back together) and possibly the heater core in front or higher than the radiator..... maybe I need to bleed the heater core?

 

Wouldn't be a bad idea at all. :jamie:

the radiator isn't the forward most part of the cooling system, there are heater hoses an lpg converter (being deleted before car is back together) and possibly the heater core in front or higher than the radiator..... maybe I need to bleed the heater core?

 

Which is why it is good practice when bleeding the cooling system to jack the front of the car up and tape a coke bottle or the like upside down over the radiator cap (with the bottom cut off and partly full of coolant) to raise the hydraulic head of the system so that it resides in the bottle and not in the piping or heater core

 

Cars with parts of the cooling system higher than the radiator cap are notorious for cooling problems - VL Commodore anyone?

Was just about then mention the commo when I was reading your reply Hiro, but then you beat me to it. The holdens engineering for you though. The RB30 skylines didn't have the same problem.

Was just about then mention the commo when I was reading your reply Hiro, but then you beat me to it. The holdens engineering for you though. The RB30 skylines didn't have the same problem.

 

That's because the front of the R31 is a box rather than the VL's slightly angled box.

Once again, Holden going for "style" over actual common sense, a practice confirmed with just about every HSV bodykit ever since.

Edited June 23, 201016 yr by Hiro Protagonist

LOL I work for Holden and HSV..... LOL again!!

 

I had a neat little thing for bleeding cooling systems when I worked for Peugeot, it was a largish 2lt or so filler bottle with a radiator cap fitting on the bottom, you could put in on in place of the radiator cap and fill it, and the two litres of fluid under gravity would assist in the bleeding of difficult cooling systems (think peugeot 307 or 406 with dw10td engine). I haven't seen something quite that good since I left!

 

Robert.

Which is why the RB30 has a bleed screw on the top hose before the thermostat.

back to original topic:

 

just put thermostat in a bowl, boiled the jug and poured boiling water over it...... not sure how fast these things are supposed to open but its opened a few mm, more on one side than the other after maybe a minute..... don't think thats quite right!!

 

on the basis of this investigation and discussion, I'm going to go out on a limb and say that as the combustion rings on the HG all look clean and nothing screams out "blown" I'm going to say that the HG wasn't blown.... yet.

 

Keith, feel free to give me a bit of shit lol.

 

still got oil pressure issue and oil consumption issue to sort out. I have access to a good bottle brush hone now, and I've purchased a complete gasket set on trademe.co.nz for a good price, just gotta get bearings, pistons and rings, and thrust washers.

 

Robert.

:looks for shit-throwing emoticon: :yes:

 

So, are those going to be oversize pistons, which will sort out any problems with your over-honed bore and make the hone you've just bought redundant...

 

Just toss the block in for a clean and a bore and you know its all done properly.

 

What do you reckon on the oil pressure?

didn't buy a hone - borrowed one. and being a bottle brush hone it should take a minimal amount of material off the bore...

 

there are a few small scored that are deep enough not to go away and I'm umming and ahhing about what to do.... might end up boring and oversize..... haven't ordered any parts off anyone yet.

 

going to measure it up anyway, I've got some specs...

 

as far as the oil pressure goes, there is significant wear in the mains and the cam bearings, and scoring in everything...

 

pretty sure there wasn't wear in the oil pump or leaks anywhere internally, but I'll check it out again anyway.

 

Robert.

there is significant wear in the mains and the cam bearings, and scoring in everything...

 

Cheap oil filter... should have gone genuine! :D

 

Weren't those new mains? There must have been something in the oilways.

 

You going to tie it on the back of the motorbike and take it 50km into work to clean it?? :yes:

mustn't have got all the crud off it from when I honed it with the block in the chassis.... mains weren't new, big ends were.

 

I degreased and pressure washed it tonight, then honed it with the bottle brush hone (borrowed from work!) and cleaned it thoroughly several times and oiled it all up.... I'm getting obsessive over cleanliness lol...

 

I'm using 90915yzzd2 filters for everything I own these days as I work next door to toyota....

 

I'm going to measure it up, but I think I'll find the bore OK (unless its been honed too much) and the pistons worn. It was making a noise that I think was piston slap when it was running and there appears visible wear on the skirts of the pistons.

 

need new cam bearings, mains, and probably big ends (they are scored badly). crank doesn't appear scored, will measure and check it though.

 

will investigate oil pump and measure clearances - new oil pump wasn't that dear...

 

Robert.

scratch marks in the bore that won't hone out are above oil ring anyway!

Put it inside the garage with both heaters on and I'll come around in the weekend!

 

Looks like it will be freezing.