The V8 Owners Forum -

Finally got round to getting underneath the engine to try and see where the coolant and oil leak was coming from. Up until then I believed it was coming out of the rear seal and or back of block.

I was surprised and disappointed to see it coming from the head gasket on both sides, particularly since the engine has only done around 2k since rebuild/install.

Looking back through the posts here it seems to be a fairly regular issue with composite gaskets and stretch bolts - and I built mine with both!

So now I need some advice on replacements...

I'm not a fan of tin gaskets, so which are the best comp gaskets and are any available with extra sealant around the oilway & waterway?

Does copper gasket sealant improve the sealing of comp gaskets?

Studs v non stretch (HT) bolts - are studs worth the extra dosh?

Any other tips or hints?

Just to confirm that it's a 3.5, P6 'S' block with 14 bolt SD1 heads (outer bolts just pinched). The block and heads have been skimmed and were flat and true when installed.

Chris.

Never have issues with composite gaskets. Not even with boost But have ARP bolts that does the trick.
I always re torque heads after 600 miles stated or not stated in the manual.

Another point, your torque wrench, is it accurate ?? cheap ones don't come with a certificate with the deviation in measurement noted.
Have had cheap ones 30lbft out. Did costs me 3 pairs of head gaskets before I figured out it was not the engine having a problem, it was the cheap torque wrench instead.

Good ones should be tested once a year. If I borrow one in a local garage I first ask when is it last checked and certified.

Thanks for the reply JP.

Excellent point about the torque wrench. Mines a few years old now - time to invest in a new one!

Definitely going to invest in ARP studs, despite the cost.

Chris.

FWIW I went for the studs from John Eales, I haven't compared them side by side but apparently the thread into the block is longer and less likely to pull out.

Composite MLS gaskets seem to get good reviews but they should considering the price of them! If I ever pull the heads off my engine again I will fit them. I like the fact that they do over size holes for the cylinder bores, I would go to over size even though my bores are standard 4.6 jobbies. The reason for this is that the fire ring on a standard sized gasket is only half compressed due to the huge chamfer at the top of each cylinder.

Never known OE head gaskets (Elring) to be an issue in fact far from it even when used with OE stretch bolts however I use the former with ARP head studs, I have known people to use the stretch/yield bolts torqued to 70 lbs and no known issues so far

Misterb_57 wrote:Thanks for the reply JP.

Excellent point about the torque wrench. Mines a few years old now - time to invest in a new one!

Definitely going to invest in ARP studs, despite the cost.

Chris.

If it is a decent make torque wrench, get it calibrated. Likely to then be more accurate than a new one. If a poor one, you have the answer. You do know to return it to a low setting when not in use? If it's been left on a high setting, it will likely be well out.

I doubt bolts or studs would make any real difference to your problem. There must be something wrong with your faces, gaskets or torque settings. And if both heads are leaking, most likely the torque setting.

The OP stated that he used stretch bolts.
Unless the torque wrench is way out, the initial 15 lbf.ft torque on the bolts is unlike to be far out.

It's doing the second stage 90 degree turn that people hold their breath and will some times give up at 75 degrees. I have been guilty of this.

Does anyone have a torque wrench that will do 15 lb sq in? Both of mine start at 20.

DaveEFI wrote:Does anyone have a torque wrench that will do 15 lb sq in? Both of mine start at 20.

I have one.
It's 15 lbf.ft not 15 lb sq in.

Yes - sorry for the typo. But 15 ft lb is a pretty low setting. Most things on a car that need a torque wrench - here at least - are rather higher. I've managed with mine which start at 20 ft lb for many a year. So I'm glad I stayed with the ordinary bolts.

Misterb_57 wrote:Finally got round to getting underneath the engine to try and see where the coolant and oil leak was coming from. Up until then I believed it was coming out of the rear seal and or back of block.

I was surprised and disappointed to see it coming from the head gasket on both sides, particularly since the engine has only done around 2k since rebuild/install.

Looking back through the posts here it seems to be a fairly regular issue with composite gaskets and stretch bolts - and I built mine with both!

So now I need some advice on replacements...

I'm not a fan of tin gaskets, so which are the best comp gaskets and are any available with extra sealant around the oilway & waterway?

Does copper gasket sealant improve the sealing of comp gaskets?

Studs v non stretch (HT) bolts - are studs worth the extra dosh?

Any other tips or hints?

Just to confirm that it's a 3.5, P6 'S' block with 14 bolt SD1 heads (outer bolts just pinched). The block and heads have been skimmed and were flat and true when installed.

Chris.

If you are happy that the decks and heads were flat I think that your torque wrench may be knacked mate ?
I gave up on stretch bolts years ago. I dont like them. I used old non stretch bolts a few times on many engines with no problems. I eventually fitted a set of ARP head studs. I have re used this set of studs about 20 times now on various rebuilds over the years.
These days I use Elring composite head gaskets. I really like these

I only needed to use the copper gasket sealant when I was on the ragged edge with my Rover V8's when I was running huge amounts of nitrous on the engines? You should not need to do this unless you are pushing the engine above its design limits like I have

For a stock Rover V8 of any size that I have built for normal road use I always use Elring comp gaskets and non stretch bolts or an ARP stud kit.

If you are seeing coolant and oil seeping out of the head to block area then your heads and or deck are not flat... OR! the heads are loose??

The fact that you are seeing this leak from both heads does seem to confirm my thoughts??

DaveEFI wrote:Does anyone have a torque wrench that will do 15 lb sq in? Both of mine start at 20.

We do torques as low as 100 inch pounds in some applications on our choppers.

unstable load wrote:

DaveEFI wrote:Does anyone have a torque wrench that will do 15 lb sq in? Both of mine start at 20.

We do torques as low as 100 inch pounds in some applications on our choppers.

Oh indeed. I have torque screwdrivers too. Just nothing that does 15 ft.lb.

Although my torque wrench is old I've always (without fail) wound it back to zero after use. Will get it checked out first, before I shell out on a new one.

Thanks for all you posts and comments. Definately be checking the heads and decks again - both have been skimmed!

Who sells Elring gaskets.

Trouble is I put the engine back together years ago (2007) and then parked it in a corner, while I finished the restoration - then last year it all came together. So Im struggling to recall details.