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Head Gasket


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My Eclat is giving me some worries, there is steam coming from somewhere below the lower rocker box. I have to conclude that I have a gasket problem. I have tried Kseal which has not cured it, I might try a second go at this as the leak is small (only slight wisps of steam!), the oil is clear so no leaks into the sump.

My questions are, is there anything else to try before I take the head off, do I have to take the engine out to do it and what else should I do at the same time.

All advice is welcome.

Peter

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Hi Peter, You certainly don't need to remove the engine to take the head off but it depends what you then find and then need to do thereafter.

Do you have facilities (engine crane, space etc). Personally I'd avoid putting anything in the engine to solve the problem as these 'cures' tend to hide a bigger issue which may/will come back to bite at a more inconvenient time. Sorry, that isn't particularly positive but I bit the bullet with my last car and doing everything myself (as far as I could) was an education.

Is the price for that bit in Yen or £?

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So it is possible to get the head off and out of the car without moving the block, yes I do have the lifting tackle if need be.

it just seems darn hard to get to the lower down stuff without being a gynaecologist.

peter

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I'm not sure if you need to loosen the engine mountings to improve movement/access but I know of at least 2 cars where the head has been removed and the engine is still in situ.

@phil flash might be able to ellaborate

I assume the cam cover gaskets aren't leaking oil (can't see that being steam though?)

Is the price for that bit in Yen or £?

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Peter,

Yes, head can come off with rest left in situ. Getting exhaust manifold off is the worst bit. Need to release the exhaust downpipe pipe from the manifold, support engine with jack & block of wood under the sump to release engine mountings. Lotus Manual says remove LH  engine mounting mounting but I found it easier with both off to lift engine and move it to offside a bit to get at exhaust manifold and remove it, otherwise it's very tight to the chassis rail & body.

Good idea to get plenty of big boxes to keep all the bits that are coming off and a few tubes of Deep Heat for back ache...

My procedure was, if I remember correctly ... remove bonnet completely. Put car on ramps at front to drain cooling system and release downpipe while underneath. Support engine & loosen mountings.

Leave it on ramps, it makes engine higher so less backache.

Remove

air duct and airbox from carbs, cambelt guard

Inlet manifold with carbs,

plug leads and plugs,

Underneath to remove engine mountings and then jack up engine and push towards offside to access exhaust manifold securing nuts (x 12). This can be tricky if they've never been off as not much rotation of spanner or socket handle available and some may be rusted solid. I used a powered 1/2" ratchet handle on some, bent ring spanners on others, 1/4" drive sockets to get to others. When I rebuilt I fitted new studs with brass nuts from my Cooper S days to make future removal easier. Stainless studs are available now too. (Once manifold is off the rest is easy!)

Remove cam covers and check valve clearances (in case any need shim changing at rebuilding). Remove cambelt and remove cam housings with cams checking whether shims are sat on valve stem or up inside the cam followers (they can drop out and get mixed up or lost)

The manual says that some non-aircon' type water pumps may need removing to lift head but my Riviera had aircon' so not an issue for me.

Release head nuts evenly and progressively in reverse order of tightening sequence working diagonally inwards (so 10,9,8, etc )

Tightening sequence shown in manual as 

 8   6   1   3   9 (Exhaust side) -> Front

10  4   2   5  7  (Inlet side)

Lift head evenly on studs to remove. Engine has wet liners so I made up some steel straps to go between studs 3 to 5 and 4 to 6 with tubes cut to length retained by head nuts to clamp the cylinder wet liners. Manual warns against turning the engine with no head can shift liner if it isn't clamped. Get a bit of 'crud' in coolant under it and it won't go back down properly and it becomes 'an engine out' job!

On rebuild 

Torque for tightening head on oiled stud threads is 70 lbs ft for all, then ONLY 3 pairs in middle (1 to 6) up to 75 lbs ft.  (and always fit a new cambelt) 

Any other questions?  Happy to help. Have re-valved head and done complete engine gearbox rebuild but some time ago. Have Lotus Workshop & Parts Manuals if any info needed so just ask...

Phil

 

 

 

 

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Phil           Leave me alone I know what to do - I think. 

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Phil - top man. I knew you'd deliver the goods.

Replacement of head........

reversal of the above, except you must leave it in your garage for at least 4 years before putting it back together :devil:

Is the price for that bit in Yen or £?

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Not sure where Peter's steam is coming from though....  where's the " lower rocker box " ???  :)

Phil           Leave me alone I know what to do - I think. 

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  • Gold FFM

get a mirror on an extending rod and have a good look and see if it's possibly a core plug leaking. Does it lose much coolant.

 

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Thanks for the advice, the steam is probably just a tiny weep that is dripping onto the exhaust somewhere. I will get the car on ramps and have a proper look before doing anything drastic.

Do I need to  use gasket sealant on the head and will it go back flat without skimming?

Thanks again to all

Peter

Sorry Phil lower rocker box is the exhaust cam cover.

peter

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I guessed you were talking about the exhaust cam cover, just having a joke....

May also be worth checking it isn't weeping out of a hose and running along the joint between head and block and then onto the exhaust. Blue paper towel off a garage forecourt is useful to wrap round hoses to trace leaks as it goes dark blue when wet.

If it is just a small external gasket weep it may be worth taking the cams off to get to the head nuts and just checking the head is correctly torqued down before you go to the trouble and expense of removing the head.

Remember torque figure is for 'oiled threads' so maybe a bit higher if dry.

If you do replace head gasket it should go on dry apart from a ring of Wellseal around the oil pressure hole on both sides, according to the Manual.  Double Click here  >>>>>     Wellseal

Heads are quite substantial and shouldn't need skimming unless they've been 'well cooked' and bowed or warped, or been eroded by gasket failure. An 18" engineer's steel rule and a set of feeler gauges is one way to check for flatness. I've also found the black glass ceramic hob in our kitchen makes an excellent surface table - but be careful on the glass, the head is quite heavy, (and I only use it when my wife isn't around !)

Phil           Leave me alone I know what to do - I think. 

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I'd still take the engine out - it's only a few hours to do.  Get an engine stand, do the job indoors in the warmth.  Enjoy doing it, rather than hating every minute.  Check out the state of the liners, swap all the o-rings and cam front seals, and the like.  

Doing  it in-situ sounds like utter misery to me.  There is really not a lot of clearance on the exhaust cam assembly side, and doing things like the shims is a real fiddle. 

 

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Quote

Do it in the car, getting the engine out is a pain, there are several excellent threads on the forum on the detail, cost wise, its only a few pounds to get the head skimmed. Well worth running it down to a engineering shop. I have done both my cars over the years its very straight forward. take extra care the liners don't move, you need to clamp them down as soon as the heads off. Keep us all undated on progress.

John

 

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I wouldn't skim the head unless it needs it. Check if it's flat and if not then skim it by all means but there can be significant consequences. If you skim the head the valves will be closer to the piston crowns when they're at TDC and a bit of clearance checking is needed. It's already quite tight, hence the valve cutouts in the pistons.. 

At max revs, con rods stretch to their maximum on the exhaust stroke, exhaust valves can 'float' and pistons can rock slightly on the gudgeon pin and will be high on the exhaust side with exhaust valve open so dynamic clearance will be less than static clearance. You'll need to do some checking of valve to piston cutout clearance. You can use Plastigauge, Plasticene or even Bluetac in the piston valve cutouts. If your new head gasket has the same part number as the old one it should end up the same thickness when torqued down so you can refit the head with the old gasket torqued down to do the measurements and refit the cams with the valve clearances correctly shimmed and carefully turn the engine by hand without too much force. Then remove the head again. If I remember correctly at least 80 thou' static clearance on the inlet valve and 100 thou' on the exhaust valve is needed but may be worth looking around the internet to check that.

After you've 'squished' whatever you put in the valve cutout, inspect it too make sure no piston is showing through, it shouldn't be because that's certainly 'interference' at max revs, and then carefully cut a section out and measure the thickness. If you've got the desired clearance you can continue to refit the head with new gasket. if you haven't the valve cutouts in the pistons will need to be deepened to achieve the clearance.

Quite a lot of work for skimming a head if it didn't need it.  Also..Compression Ratio will increase if the head is skimmed, reducing the combustion chamber depth and there may then be issues with 'pinking' and ignition timing that need to be addressed. 

So I'd say check if the head is flat and don't skim it 'willy nilly' - think the expression is "If it ain't broke, don't fix it."

Phil           Leave me alone I know what to do - I think. 

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  • 4 months later...

Hi,

I posted elsewhere on here about how well my 2.2 is running now -and it still is over 160 miles now

-- but it is drinking the water way too heavily with no evidence of leaking, about a litre every 50 miles.

...the past 4 trips in it have confirmed the presence of water with the oil and mayo under the oil cap, so I am forced to think its a head gasket issue. Keeping it topped up with water isn`t going to work in the long run.

Tried K-Seal and have driven about 110 miles since  but that has worked marginally if at all.

Therefore I am going to try "Steelseal" on it next as I`ve heard good things about it, (at least if their numerous website endorsements are to be believed).

Has anyone else tried "Steelseal" and how has it gone ? 

Thanks

Dan

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Not something I'd ever consider using even on a low performance engine and particularly not on a wet liner engine or turbocharged engine where things are more critical.

Lots of vids on youtube showing it working but this one shows how it can also block waterways - 

My concern is a local blockage wouldn't be apparent from a general increase in engine temperature but one cylinder may run hot enough to melt a piston.  Melting point of aluminium is 660°C and normal exhaust gas about 650°C so cooling by waterways in head and block is pretty critical and depends on cooling by the inlet charge at the stoichiometric ratio. Running rich cools it more but running lean can result in melting pistons even when the water cooling is working properly.

They say they'll refund the cost of the product if it doesn't work but what about the cost of engine damage?

Also .... oil with water in it isn't a very good lubricant at all. With water in the oil and 'mayo' under the cap you are in danger of scuffing the cam lobes and running the bearings. Remember when you drain the oil the oil in the oil cooler and pipes doesn't come out so it can be a bit of work to get emulsified oil out of the system.

 

Phil           Leave me alone I know what to do - I think. 

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I've never used it in a 907, but I've used Holts Radweld and Barrs Leaks in other engines with good effect.

As a student I worked as a greenkeeper and there was an old International 684 tractor that had a cracked block, and a strong dose of Barrs Leaks kept it running fine as long as I didn't work it too hard. This was a crack, not just a blown gasket and it worked surprisingly well.

I'd give Bars Leaks a try before I went to the faff of whipping a head off.

 

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Thanks Dunc-There seems to be a 50/50 mix of opinion on various forums as to whether Steel seal works (including it working wonders on an Elise K-Series -ah yes the K series....:ermm:

A lot of posts refer to it making things worse - just clogging up the heater/pipes/radiator instead which would be catastrophic !

It seems vital to flush the cooling system first with (arguably) no anti-freeze at that point and a rather obvious point is that some head gaskets are too far gone to be helped (although my car still starts very easily and with no misfires).

I don`t really want to take the risk with a 912 engine as guinea pig but the alternative is bloody expensive

....sounds like the Barrs Leaks might be a good half-way solution compromise type thing.  

 

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Hello again ,

-done some more online research, seems that these substances either work or will royally screw everything up, nothing much in between.

I just don`t want to risk clogging the innards with additives any stronger than K Seal-if it goes wrong it`ll be "new engine" time.

Even a rebuild is preferable to that..... :sofa:

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A head gasket change is fairly straight forward albeit long winded. Rewarding if done right, catastrophic if timing belt position is not observed carefully.  do you have a garage and is this your daily driver?

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I simply cannot see the sense in taking the risk?

900 series engines have an enviable reputation BUT they are not tractor engines (forgive me Dunc but I used to follow a similar logic with an old Fordson Major).

The use of ANY additive is surely just a route to delaying the inevitable but significantly adding to the risk of something catastrophic happening in the medium to longer term.

Take the lesser hit now and be reassured of a job well done?

  • Like 1

Is the price for that bit in Yen or £?

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Hi I`m looking at specialists to do the job ; I note that Lotusbits are booked up until at least November so I`m asking other specialists. I know a good local guy who works on  his own Countach (!) and who  I trust but he won`t be able to to do it until April 2018, knowing him. 

If you know of a Lotus specialist apart from Paul Matty, Lotusbits, Fibreglass Services Chichester and the people in Hammersmith and the people in Newmarket  (already tried) I would be very interested to approach them for an estimate.

Thanks

Dan

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  • 2 weeks later...

I`ve noticed the water consumption go down a bit over the past few "test" drives, seems like the K Seal might be continuing to do its stuff.

But still looking at new head gasket unless a miracle happens.

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On 4/21/2017 at 16:50, basalte said:

Hi I`m looking at specialists to do the job ; I note that Lotusbits are booked up until at least November so I`m asking other specialists. I know a good local guy who works on  his own Countach (!) and who  I trust but he won`t be able to to do it until April 2018, knowing him. 

If you know of a Lotus specialist apart from Paul Matty, Lotusbits, Fibreglass Services Chichester and the people in Hammersmith and the people in Newmarket  (already tried) I would be very interested to approach them for an estimate.

Thanks

Dan

Try Lakeside Engineering at Addlestone near Woking/Chertsey or Max500.com at Guildford - both very good.  Love the old engineering workshop feel of Lakeside...

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