Head Gasket Again!!!

[My Car Pwns]

hey, as most of you's know i had a problem wit my car a couple of weeks back.. turns out i had blown the head gasket, warped the head and seized the engine all at once.. after putting a new engine in.. 5 weeks later i'v blown another head gasket.. im gonna jus buy the gasket ($40) and change it.. any suggestions? hopefully the head will still be fine.. is there any way to make the head gasket not blow..? its getting ridiculous..! im starting to hate VL's..

[rattattack1313]

Have a goood read of the manual, if you have one........make sure everything is kept clean..........look for a ridge in the top of the bore, if a large ridge is present, it needs a hone-out........make sure all the old gasket is off both surfaces.....and while the head is off, get it checked, make sure it isn't warped.......and look carefully atr where th hasket is blown....has it burnt a lot of metal on the head/block???? hope not...usually this is a prob if you have driven it for ages and ages with it blown............hope this is a little help.....

[My Car Pwns]

yer i have a manual... wot do u mean by a ridge in the top of the bore.. well wen i realised it was blown.. i didnt drive it at all.. i got it towed home.. but wen i looked at the oil cap on the head.. it was totally creamy n etc.. so i dont know how long its been blown for.. it jus heated up yesterday n i stopped driving str8 away.. u seem to know a lot about VL's should i fix n sell it? coz it seems my VL has been nothing but trouble.. if the head is gone i'l b on my 3rd engine in a 2 month period..!

[vlv8vic]

are you keeping your eye on the coolant levels? needs to be full at the radiator and also at the bleed points. bleed points are most importants as thats where steam builds and blows the head.

[rattattack1313]

Up to you if you fix & sell....sounds like you just got a few lemon motors.....and by the ridge, I mean a build-up of carbon , etc, at the top of the barrels...the pistons don't go right to the top..so there is a bit of the barrel that gets some build-up on it sometimes............while the motor is apart, best to check these things that are easily fixed, while the motor is apart......I'd fix & keep........

[harry3]

when filling the cooling system you must undo both bleeder bolts ( they may sieze and shear off if they havent been undone for a long time) and then force water into the radiator using a garden hose until it flows out both boltholes, then replace radiator cap first

otherwise a steam trap will form, water wont get to where its needed and engine damage will be done

this is a notorious problem for VL sixes, due to the top of the water passages being higher than the top of the radiator.

if the head is warped also check the top of the block

[Bax]

Just to clarify what you said there harry3.

If you park the car on a slight incline to make the radiator the top of the coolint system you should be able to trickle the water in there. WIth both bolts undone on the cooling system. Wait for water to come out of the bottom one. Do it up, then wait for water to come out of the top one, then do it up. Then put your cap back on.

[VT-565]

.....and by the ridge, I mean a build-up of carbon , etc, at the top of the barrels...the pistons don't go right to the top..so there is a bit of the barrel that gets some build-up on it

youre talking about the deck height, rat....most stock motors should run a few thou deck height, meaning the distance between the top of the piston at tdc and the deck or block height. Sorry rat, it's been a while since i spoke to yer.....

[Bucket]

did you get the head pressure tested when it got decked (machined flat) or did you just put it back on without doing either of the above.

Now they should have checked the minimum thickness and pressure tested the head for cracks, its like checking for a pulse on an unconscious guy when you'r dealing with VLs's. If not, spank someone hard ok.

When you take the head off again, the head gasket should be like a crime scene as rat said, have a look around the edge of each bore while the head gasket is still attached and look to see if oil or water stains go between any oil galeries and water jackets. If not then you may need to look at the head again buddy. (unless for some reason you got the PCV hose and the little coolant hose on the side of the plenum mixed up.

[My Car Pwns]

i havnt got it tested yet.. probably gonna take a look tonight to see if i can find the reason that this heap of shit keeps bringin me headaches..! wot do u rekn the odds are of it jus being the head gasket? 1000 to 1? lol. also if it is the head again, do u rekn it would be better to put the nissan motor in2 my VL, apparently the heads don't go on them..?

[Bax]

You'd still have to bleed the system exactly the same way.. Exactly the same motor, just that the radiator is lower in the vl. Which leaves the pocket of air in the plenum/head area.

The skylines didn't have problems with cracking heads but thats because the radiator was higher and they didn't have any problems with air pockets. But on the same note we can ditch the airpockets by bleeding the system, as stated above.

You should be able to pick up an entire engine for 2-300 dollars. Unsure of condition of course, thats the only problem with it.

Depends how much cash you've got to throw at this thing, i wouldn't bother changing engines. But if you get a new head put on professionally, and bled and you take care of it and it still cracks you may have a more serious problem.

There was a particular car on calaisturbo that had consistent problems, happened to the poor guy heaps. With many a trip to the mechanics to help him out and find a cause. I think he gave up in the end.

[tripodum]

When you have checked and cleaned very carefully, put the new one on with Hylomar. It's the answer to a virgin's prayer.

[Bucket]

thats just a spray on goo onto the gasket.


Mark do you know if the head that went back onto your car was pressure tested. Also, did you put the head on yourself, if so did you use the correct tightening sequence?

Bex, i owned an 87 Skyline which cracked the head but i think i was running around with low water for a while, it was yonks ago now.

[My Car Pwns]

i put the entire engine myself.. so i didnt change the head or anything like that.. jus put it all in.. do u think i can raise the radiator a bit..? ? i dont have too much money to throw at my project.. but im earnin minimum 300 a week..

[Bax]

You don't have to raise the radiator, just bleed the system like I've mentioned above and it will be fine.

[Bucket]

ok so you put the entire motor in at once, was the oil looking fine afterwards, as if it was running ok?

Secondly, was the temp running below half the whole time?

Every time i bleed my system, i drive it down the road cause where i live is heaps hilly, and then i turn around and flog the crap out of it all the way up the hill, it gets the car up to operating temp and forces the air to the bleeder if it wasnt done properly so i can bleed it again.

If your car is going to overheat, it will always do it under maximum load. Dont be a goose about it too much but give it some close to home and watch the temp gauge, have a little spanner on hand ready to bleed.

[harry3]

I carry a spanner for the bleeder bolts and a length of rubber hose that fits in the radiator cap to increase the water pressure in case I get a radiator leak when out in the middle of nowhere
its best to remove the thermostat when flushing the cooling system
as mentioned the VL 6 is I think unique in that the top of the water cooling passages in the engine are higher than the top of the radiator, due to holdens having to shoehorn an engine into the commodore that was never designed for it

[Rhino Racing]

Interesting reading guys. and congrats to all for some wothwhile infomation.... good to see a forum working well for someone in need.
But dont forget to KISS.... (Keep It Simple Stupid!)

All of the things mentioned are definite possibilities for your reoccuring problem.. but you have also got to go back to basics and start again.

1)The original problem might have been caused by a stuck thermostat or blocked radiator........ You said that the whole engine was changed but you did it yourself.......... did you throw a new themostat in it.....If not, does the new engine have a thermostat in it at all( this can cause issues with coolant not flowing to the back of the head properly). Or did you use the old thermostat..... Maybe it is seized partially and not allowing adequate flow through the engine.Even when fitting a new thermostat it is a good practice to test its operation before installing it. This is done quite simply..... put a saucepan full of water on top of the stove.......use a piece of wire to lower the thermostat into the water.... watch the valve open fully and you can watch it close again when it cools down, You can verify the temp that it opens if you have a thermometer to monitor the water temp.
The thermostat is basically a valve that is tempreture sensitive and will open and close to regulate engine tempreture by allowing more or less cooler water from the radiator through it.

2)Did you flush out the radiator properly or have it tested for restrictions? Years of sludge and especially after doing a head gasket the build up of carbon etc from exhaust gass is quite common and overlooked when looking for a cause.

3)When the car overheated the second time..... did it just read hot on the temp gauge or did it actaully overheat ..... did you see a loss of coolant , steam etc when you pulled up?
Cause it could be coincidental that the new engine has a temp sender unit in it that is stuffed...... and it just read high on your gauge, withiout actually cooking the donk.

4)If all of the above are o.k. then you could just be unfortunate enough to have picked up another donk with a problem in the same area.
Then you have to ask the question. Why was it removed from the car that it came out of.

5)Lastly another thing to keep in mind......... engines that have been removed from cars and sit in sheds etc for a long period of time.... are sitting there without coolant in them........ all of the seals etc on head gaskets (and around cylinder sleeves, high performance and diesel applications) will dry out and perish.... when subjected to heat and stress of normal engine operation they can fail.

Sorry for the long reply but you didnt clarify all of this in your thread.... .. ..... it pays to take a step back some time and start from scratch.

Look forward to hearing back from you about all of this.

[My Car Pwns]

thx for help you guys..
i didnt buy a new thermostat.. i flushed the radiator, but didnt have it tested, the car did overheat, since i put new engine in it heats up quick but jus stays exactly on half.. maybe jus a lil bit ova.. but i woz told that wos normal.
the car woz running fine up till then.. bit of rough idling but otherwise fine...
i dont know what u guys mean by bleed the system..

[rattattack1313]

By bleed the system, we mean for you to follow the top radiator hose towards the top of the motor...there should be a bleed valve there.......warm the motor...then loosen the bleed valve.....let all the air out of it.....

[Bax]

Yep, There are two bolts, Both have caution do not open when hot stickers next to it. Ones next to the top hose from the radiator as rat has said, the other is on the top of the plenum.

Excuse the dirtyness but heres a picture. All your doing is letting the air out of the system so the coolant can get in contact with every part. So there are no hot spots forming which causes the warping, cracking etc.

[My Car Pwns]

ok that makes things clearer.. so i do that after i fix the engine yer? but lil confused again.. the radiator hose goes to the engine.. in the pic isnt that the fuel injection? or do i bleed both?

[Bax]

You bleed both, I'll try and find you a better picture.

The picture above is the plenum, that splits the air into each individual cylinder before it gets mixed with fuel and burnt. But coolant makes its way up there too to get bled.

I'm fairly sure I've posted another thread, I'll look soon

[Bax]

I have.. Heres before I removed it.

http://forums.justcommodores.com.au/...achmentid=5867

[markandsam]

ive got a vl with a nissan rb30 motor and have been told they crack there heads too.
i do find a few drops of oil in the top of the radiator sometimes ,, but it still goes pretty well. i cant afford to get a new head as yet , if thats what it is!!