Rover V8: can a headgasket leak slightly?

[The Doctor]

On an SD1 Vitesse.

I keep loosing water (and i know it's leaking a bit around the waterpump, new one ordered from RimmerBros).

But i also have some mayo on the fillercap and it's quite rough running when started and smoking brownish. To me these 2 are signs of a headgasket failure, but i can drive it along for quite a distance without any trouble at all. All other BHGs i had so far where quite severe, i.e. dumping all the water in one go, overheating and smoking like a complete industrial zone.

The Rover doesn't do any of that, only the temperature creeps up when the coolant level is going down to much and the car is idling whilest sitting stil. And then the heater stops working.
All of that is corrected when the coolant level is ok again.






Any thoughts about this?

[penrhynrallycentre]

Got a Mgb in for work at the mo Headgasket is weeping on the back of the engine so YES it can happen,BUT best to get it done asap before serious damage is done


Dave

[dodgerover]

Yes they can especially if its got the standard all metal headgaskets, it probably has as they are a: standard and b: cheap! Our range rover must have done 20K like that before we got around to putting on some composite ones from real steel

They're easy to do if that helps

[v8ian]

you will get mayo around the filler neck this time of year from condensation, normally nothing to worry about, get the pump sorted, and see what happens,

[10mpg]

After you've fixed the pump (probably all it is) check the rubber pipes to the water pump and the front to back water rail (and pipes to the heater matrix), these often have little weeps on them which are bloody hard to spot, might just need a few pipes, also seen quite a few coreplug weeps over the years, esp hidden up on the underside of the block near the starter.....

See if you can get someone to do a leakdown test, that'll help diagnose a weeping headgasket amongst other things..

Rover V8's have a fault from the factory in that the unequal clamping forces on the head, causes them to cant over time, making the headgaskets blow into the valley, when you replace the headgaskets (if you need to) don't torque down the outermost row of bolts (above the exhaust manifolds), just nip them up, stops this problem dead, on later Thor blocks this row was deleted anyway, it just took Rover 15 years to figure it out..

Composite gaskets will pull your CR down so if you don't need them it's not essential, I've fitted both composite and tin over the years and never had a problem with either if you're head and block services are v good then you'll be fine with tin, depends weather previous owners have been religious with the antifreeze....

The rough running is probably a tired cam, RV8's hide wear very well and run OK even in dreadful condition they suffer from poor top end oil lubrication, caused by low oil pressure, and they knock out cam lobes quite regularly, couple this with a tired injection system (is yours still on the flapper system?) and Rovers truly dreadful range of distributors (if it's not a 35DLM8 then bin it and get one or preferably a Mallory if you can) means rough running cars are the norm rather than the exception..

As V8ian says a small amount of mayo this time of year is quite normal, esp on RV8's which as standard on a Vitesse basically have a condensing tube for a crank breather system..

hope this helps

[Brigsy]

Do a compression test and go from there. Fix the water pump first though it might be nowt.

[The Doctor]

Mar 1, 2012 0:53:37 GMT 10mpg said:

After you've fixed the pump (probably all it is) check the rubber pipes to the water pump and the front to back water rail (and pipes to the heater matrix), these often have little weeps on them which are bloody hard to spot, might just need a few pipes, also seen quite a few coreplug weeps over the years, esp hidden up on the underside of the block near the starter.....

See if you can get someone to do a leakdown test, that'll help diagnose a weeping headgasket amongst other things..

Rover V8's have a fault from the factory in that the unequal clamping forces on the head, causes them to cant over time, making the headgaskets blow into the valley, when you replace the headgaskets (if you need to) don't torque down the outermost row of bolts (above the exhaust manifolds), just nip them up, stops this problem dead, on later Thor blocks this row was deleted anyway, it just took Rover 15 years to figure it out..

Composite gaskets will pull your CR down so if you don't need them it's not essential, I've fitted both composite and tin over the years and never had a problem with either if you're head and block services are v good then you'll be fine with tin, depends weather previous owners have been religious with the antifreeze....

The rough running is probably a tired cam, RV8's hide wear very well and run OK even in dreadful condition they suffer from poor top end oil lubrication, caused by low oil pressure, and they knock out cam lobes quite regularly, couple this with a tired injection system (is yours still on the flapper system?) and Rovers truly dreadful range of distributors (if it's not a 35DLM8 then bin it and get one or preferably a Mallory if you can) means rough running cars are the norm rather than the exception..

As V8ian says a small amount of mayo this time of year is quite normal, esp on RV8's which as standard on a Vitesse basically have a condensing tube for a crank breather system..

hope this helps

Wow, a lot of info there!

I'm a Rover (and english car) newbie, so bear with me, i'm going to answer as much of the questions as possible.

The oil pressure on the gauge is sitting at around 30psi when driving around, is this good or bad?
BTW, it runs perfect when warmed up, it just doesn't like to be idling when cold.

Don't know about the injection system, it all looks stock, and it's a single plenum one, I guess there's an airflowmeter in front and probably stock.
I also don't know what distributor I have, all I know is, that it's much bigger then the Toyota ones i'm used to!

I'll go and do a leak test this weekend (fingers crossed it will pass MOT tomorrow )

2 pictures from the engine i made last week.

[bl1300]

Mayo around the oil filler can be caused by condensation so on its own is not nessesarily a problem. HG can weap slightly and if they do they will blow completly eventually. If it was mine id fix the water pump and run a compression test, if its ok then id just keep a close a close eye on the water level and if its still dropping do the HGs

[mt2man]

I thought my head gasket was on the way out because i was loosing water and some mayo. I kept topping it up with water but then realised there was probably no antifreeze in it.

Topped it up with antifreeze and havent had a problem since, i guess it was just boiling or evaperating off or something? The antifreeze seems to have sorted all my problems.

[10mpg]

First of don't trust the gauge Rover oil pressure gauges esp on SD1 are pure fiction most of the time, one of my SD1's the gauge actually started working in reverse...

30psi on the gauge if it's right is ok when driving around, I'd like to see more, but 30psi will do no harm it does mean either your engine or oil pump is a bit past it's best, what it does at idle is more important, you should have around 20psi at idle if the engine was healthy in reality anything over 10 will be ok, I've seen engines that sounded ok that dropped to 0 at tickover, like i say they will take huge abuse before failing completely, a legacy from their American roots..

Your injection system looks standard and is what is known as the 'flapper' system, you'll understand why if you look into the afm.. these are ok and usually keep working, but they are renown for niggly problems, later 'hotwire' systems are better even these are quite compromised..

That said even though they're fussy, they're quite easy to diagnose at home, i suspect you may have a worn flapper a couple of tied injectors, maybe a duff sensor...

[nomad]

"can a headgasket leak slightly?"
Yep, I had a Nissan 1.8 Turbo that was leaking between 2 pots, ran fine like that for months, no oil or water problems just uneven running and low on power.

Fix what you know is wrong (waterpump) then check the other bits.
Mayo - could be condensation if it's just used for short trips and never gets hot to burn it off.
You should be able to find a local garage that can do a "sniff test", their machine checks the water in the rad, if h/gasket is gone the machine tells you, quick and simple proof for you

[ChasR]

I also believe that an emissions tester will work for testing whether the coolant has mixed with oil by putting the probe near the coolant in the header tank.

Whether it is true or not is another matter.

[v8ian]

RV8s design is well over 50 years old now, admittedly its been a progression of upgrades over the years, The Oil system on them is a high volume system rather than high pressure system, run the engine on 20/50 mineral oil and it will last for ever