Engine 850: B5254S/2.4/20v: Head Gasket failed, head off.. what next?

[dinky1]

Hi Guys!

I've been absent for several years now - sorry about that - but i still have the safrane parked up outside and up on axle stands.

So last time i was here i mentioned that it had HGF. This was confirmed with cylinder pressures being all out and the dreaded mayo - even after an oil change. I was gutted.

Anyway i put in the spare engine, that ran reasonably well for a while, then decided also to go the same way - white mayo, coolant loss etc. FFS.

Anyway i found the problem which was causing the cooling fans to malfunction - an airlock. I tipped the car up on it's side one day to take photos of the fuel lines and then the fans started working the next day. They then stopped again so it's an airlock in there and having now found the radiator cap needs to be pulled out not just turned 90degrees.... urgh..

Right so the replacement engine has HGF. I've had the head off today, the stretch bolts have rust on the threads. The gasket itself has lots of lovely mayo at the back of cylinders 3,4 & 5.

Cylinders don't seem too bad, couple of specks of mild rust and thats about it.










So whats my options here?
Will the stretch bolt holes be screwed due to the rust?
Also if i get the head skimmed, will the camshafts be ok? - i read years ago on a site elsewhere that a lady had hers snap after a skim..

I can't really replace the head as renault charge silly money for them and they are modified - the renault version has a large engine mount on top that the volvo doesn't have and the bolts go directly into the head:



Also as you can see in this next picture, on the gearbox end of the engine is a lifting loop - which unlike the timing side, is attached directly to the head.



I can't help but wonder now, is the way i've crane'd these in and out the cause? - I've always removed it with the gearbox attached - extra weight on that side of the lower engine & loop / stretch bolts on that side of the engine - which of course as you see in my photos above, are the 3 cylinders with mayo on the gasket.



So whats my way forwards here?

Should I skim? Should autobox somehow be removed first in the future? or should i wrap a chain under it and lift like that to avoid strain on the stretch bolts?

If i skim, will the camshafts survive?

So many if's and buts... sorry lol..

[winsox]

Originally Posted by dinky1

Hi Guys!

I've been absent for several years now - sorry about that - but i still have the safrane parked up outside and up on axle stands.

So last time i was here i mentioned that it had HGF. This was confirmed with cylinder pressures being all out and the dreaded mayo - even after an oil change. I was gutted.

Anyway i put in the spare engine, that ran reasonably well for a while, then decided also to go the same way - white mayo, coolant loss etc. FFS.

Anyway i found the problem which was causing the cooling fans to malfunction - an airlock. I tipped the car up on it's side one day to take photos of the fuel lines and then the fans started working the next day. They then stopped again so it's an airlock in there and having now found the radiator cap needs to be pulled out not just turned 90degrees.... urgh..

Right so the replacement engine has HGF. I've had the head off today, the stretch bolts have rust on the threads. The gasket itself has lots of lovely mayo at the back of cylinders 3,4 & 5.

Cylinders don't seem too bad, couple of specks of mild rust and thats about it.










So whats my options here?
Will the stretch bolt holes be screwed due to the rust?
Also if i get the head skimmed, will the camshafts be ok? - i read years ago on a site elsewhere that a lady had hers snap after a skim..

I can't really replace the head as renault charge silly money for them and they are modified - the renault version has a large engine mount on top that the volvo doesn't have and the bolts go directly into the head:



Also as you can see in this next picture, on the gearbox end of the engine is a lifting loop - which unlike the timing side, is attached directly to the head.



I can't help but wonder now, is the way i've crane'd these in and out the cause? - I've always removed it with the gearbox attached - extra weight on that side of the lower engine & loop / stretch bolts on that side of the engine - which of course as you see in my photos above, are the 3 cylinders with mayo on the gasket.



So whats my way forwards here?

Should I skim? Should autobox somehow be removed first in the future? or should i wrap a chain under it and lift like that to avoid strain on the stretch bolts?

If i skim, will the camshafts survive?

So many if's and buts... sorry lol..

Hello there

You are lifting it fine, the volvo lift point on the back of the engine also connects to the cylinder head, but also the base. I would not worry about this.

Check the head and if needed have it skimmed, personally id just skim it.

You will see bits of rust in it as its been sat long. Just flush it all out when you can, especially coolant passages.

[CNGBiFuel]

That's how I lift mine. Even have the same cheapo 'sale-ends-soon' - "To you twenty-two sobs" load-leveller. Skimming is always cheap. It's the hassle getting it set-up to do it, et al that you'd want to avoid. However it'd be wiser to bite the bullet. I'm about to do one myself. New rings etc whist I'm on. About now, RobertDIY is your best mate.

[Familyman 90]

Get the head tested for trueness - if there's any variation then get it skimmed.

[Clan]

Originally Posted by Familyman 90

Get the head tested for trueness - if there's any variation then get it skimmed.

The problem is Renault use their own gaskets poor quality compared to the volvo ones . volvo use green gaskets and Renault cheap black ones which crumble after a while .That maybe what let air into the cooling system.

[dinky1]

Hi Guys!

Sorry i've only just seen your replies, did check a day or two after posting but there was nothing so i figured there was no interest - clearly i got that wrong!

Anyway i've put it in for skimming and had the head washed out of all the oil and shavings in another garages special head washing machine. He checked the head and then the cam shaft bearings and he said the bearings are still straight and it should be ok - phew!!! It came out looking a hell of a lot cleaner - i wish i'd taken the rocker cover and the rest of the engine in too!

After posting i think i might have found another serious cause of this engine going the same way as the first. The ecu has been failing to turn on the cooling fans. I was asked one day to take photos of the fuel lines for another safrane owner so i jacked it up at a steep angle and got snapping. The next day the cooling system ran wonderfully for the first time in around 4 years and continued doing so for 1.5 hours until i cut the engine. Day after that, dead again so i figured there was an air lock in there somewhere that had shifted. The radiator cap has always been an issue on these and has stumped other safrane owners. It turns 90 degrees to the open position but the manual left out something - you then have to put grips on the thing and pull it out to expose a big air hole So now it looks like i had a load of air trapped in there via the rad that was buggering up the coolant sensor - even though the dashboard was still showing the temperature.

@Clan yes i've heard about the gaskets before. This one has come apart with the green ones though including for the thermostat housing so renault have done a half decent job on this engine - kinda. I'm in touch with the volvo dealers by email who are trying to put together a replacement gasket set for me. There is some confusion as to what engine it is as it was supposed to be a B5244S going by the 2435CC /168hp thing and the rest of the specs however the dealer said it can't be as it wasn't used for an 850 so it's now looking to be more like a B5254S or B5254FS - both of which are 2435CC too - odd! What renault have done to this engine though is to modify it in a few ways - the cam pulley wheels have been swapped (exhaust is now inlet and vice versa) meaning the timing marks are useless. The timing cover is also different (still stamed "Made by volvo" though) so the timing marks are still redundant anyway. There is a mount on top of the engine with a bolt going into the head at a really weird angle (just to ensure you can't use a volvo head - swines) and they've given it a different lifting loop above the gearbox than the volvo units, inlet and outlet manifolds are also different along with the recirculation system. There may be other differences too but none that i can remember off the top of my head. You'd definitely recognise it as a volvo if you saw it but you'd also see immediate differences too.

@CNGBiFuel I got fed up with that load leveller. It's good for smaller engines but for the 5 pot volvo it just wasn't long enough so as you can see i had to come up with my own extension to it (works very well). The original leveller kept bending the lifting loop inwards over the rocker cover. An old friend found me a bit of steel bar in his scrap metal collection (RIP Mike old pal) which i then cleaned up with a wire brush on the grinder, cut to length, drilled holes and smothered in hammerite. It's been a great tool and was the best thing he could leave me with to remember him by. I had wanted to simply make a longer load leveller but trying to find the same threaded bar to go through the sliding mechanism was impossible. None of the engineering companies round here could replicate it (only syaing "years ago when we had the right tools we could have done that for you but not now.."). I even contacted the manufacturers and they were very hostile towards me over it with one reply simply stating "dont want to help you" - charming!

Anyway I've got the skimmed head in the garage upside down sitting on polystyrene and wrapped in bubble wrap with oil on the surface to me mounted over the cylinders (the lower half of the engine is also greased). I'm just waiting on the final details for gaskets, stretch bolts etc so that i can crack on and start rebuilding it.Thanks for the sterling advice, i will take some pics and keep you updated!