Replacing Head Gasket - Tips, Tricks and Helpful Advice

[Jock The Rock]

Gday

I'll be pulling the head off (300Tdi) hopefully on Thursday, getting it lightly skimmed on the Friday and getting it back on, on Saturday/Sunday

I was just wondering if anyone can offer any advice, hints or tips that might come in handy?

I read in the Workshop Manual I can resuse the bolts up to 5 times. So, as this will be the first time I'm planning to reuse the bolts

[justinc]

Gday

I'll be pulling the head off (300Tdi) hopefully on Thursday, getting it lightly skimmed on the Friday and getting it back on, on Saturday/Sunday

I was just wondering if anyone can offer any advice, hints or tips that might come in handy?

I read in the Workshop Manual I can resuse the bolts up to 5 times. So, as this will be the first time I'm planning to reuse the bolts

Good evening young Hamilton

Nothing unusual in this job, yes you can reuse your head bolts, make sure you use Elring gaskets, and clean the bolt holes and block surface thoroughly.
Don't forget to re tension the first stage (45Nm) as by the time you get to the last 4 bolts, the first few have become looser. IE recheck them all at 45Nm before attempting the 2nd and 3rd 60Deg stages.
Valve clearances will be way out after so make sure you do them again, and recheck them after a drive/ initial warm up.

You should have it knocked over in a day easily

Any Q's, give me a call on the mobile, I'll be at home Sat.

JC

[discoveryseries1]

Gday

I'll be pulling the head off (300Tdi) hopefully on Thursday, getting it lightly skimmed on the Friday and getting it back on, on Saturday/Sunday

I was just wondering if anyone can offer any advice, hints or tips that might come in handy?

I read in the Workshop Manual I can resuse the bolts up to 5 times. So, as this will be the first time I'm planning to reuse the bolts

use carb cleaner to clear the oil off the block and heads, get the head re conditioned when its off, even if its just a valve lapping, pop new valve guide seals on the valve stems, its heeps of value for money, apecaly scince you have the head off alredy, pull the core plugs out and pop in brass plugs, you may as well do it all when its off to save time and money later, and have peace of mind when it goes in, eg i just rebuilt and re engineered my engine and poped it in, i skimped on an oil seal that i forgot to get and said well she will be right, now next weekend i have to pull it agin it has an oil leak on the main. cost,...... 300 to buy an engine crain and 50 bucks for 2 new seals, i dident have to buy a crain, but the engins i have pulled i have bought some one a crain by now,

- machine head,
-lap valve seats
-new valve stem seals
- brass welsh plugs,
- stainless head exhust studs,
- all fasteners with anti seaze aspecily exhust studs,

as much anti sease as you can put on the studs with out barfing on them.

thats just me tho, when its out you may as well do it while she is out and toey.

let us know how she goes mate,

[discoveryseries1]

woops, i forgot to mention , on the oil return inside the head, eg the oil gets pumped up into the cam via the bearing caps holding the cam, and then trickles out and spills over the valve springs, ect, then falls down and through the holes in the head, where the holes are, you will see a casting inprefection where the hole is there will be a small razor type cast left behind. take a die grinder with a 1/4 inch end mill and take the burs out and open it up, the objective is to alow the oil to trickle through the hole as soon as possibul and avoid a build up of oil. when the engine is shut off, you have a hot head and thin layer of oil on it , not flowing because the pump is off, then the oil bakes on from the heat, this causes the build up of sludge, a killer in engines, mine was full of it from pore serviceing from prior owner and dirt injestion. the oil flowing into the engine faster also helps with lubracation recurculation aspecaly in the event of a low oil situation. dont get carried away boring and all that , its just to help the flow.

i ported mine too, just a touch up to get the sand marks off the head ports. let us know how you go.

rember if you havent modified evrey thing and made it better,...... keep working on it....

[Jock The Rock]

Good evening young Hamilton

Nothing unusual in this job, yes you can reuse your head bolts, make sure you use Elring gaskets, and clean the bolt holes and block surface thoroughly.
Don't forget to re tension the first stage (45Nm) as by the time you get to the last 4 bolts, the first few have become looser. IE recheck them all at 45Nm before attempting the 2nd and 3rd 60Deg stages.
Valve clearances will be way out after so make sure you do them again, and recheck them after a drive/ initial warm up.

You should have it knocked over in a day easily

Any Q's, give me a call on the mobile, I'll be at home Sat.

JC

Good evening not so young Cooper

Alan sent me an elring gasket so thats good

Trouble is Thursday is a public holiday so the head machining place won't be open

I understand this is a bit of a tricky question but why to you think my head gasket blew with the number of ks the motor has on it? Just age and the gasket weakening?

woops, i forgot to mention , on the oil return inside the head, eg the oil gets pumped up into the cam via the bearing caps holding the cam, and then trickles out and spills over the valve springs, ect, then falls down and through the holes in the head, where the holes are, you will see a casting inprefection where the hole is there will be a small razor type cast left behind. take a die grinder with a 1/4 inch end mill and take the burs out and open it up, the objective is to alow the oil to trickle through the hole as soon as possibul and avoid a build up of oil. when the engine is shut off, you have a hot head and thin layer of oil on it , not flowing because the pump is off, then the oil bakes on from the heat, this causes the build up of sludge, a killer in engines, mine was full of it from pore serviceing from prior owner and dirt injestion. the oil flowing into the engine faster also helps with lubracation recurculation aspecaly in the event of a low oil situation. dont get carried away boring and all that , its just to help the flow.

i ported mine too, just a touch up to get the sand marks off the head ports. let us know how you go.

rember if you havent modified evrey thing and made it better,...... keep working on it....

Thanks for the suggestions mate

When you say brass welsh plugs you mean the ones in the top of the thermostat housing and top of the radiator?

Also I don't reckon my head will need doing up, the engine has only done 94k

Also when you suggest deburring that part, won't I end up with little metal filings all the way through my engine?

Thanks

[lyonsy]

shove rags into the cylinder's when your clean the deck blow out then carfully remove and throw rags away where not used again for rebuild.
then pour oil into pot's and wind the engine over by hand untill you no longer get any crap coming up the cyinder walls may need to re oil several time's it will be sand and sand and rings dont mix.
when doing the block get wet&dry 600 and crc it and use ether a block of wood or steel so you dont make the surface of the block uneven.
dont use anti sieize on the bolts ideal use mollybond grease otherwise use engine oil the chemical make up of anti seize can cause problems in the oiling system.
also check black surface is flat with flat edge anything up to 2 thou is ok.

id reconmend getting the valve's checked for wear and put some guide seals while all apart.

as a bit of extra insurance on the gasket get some hylomar and spare the head gasket good stuff will help it, spary stuff should be more then enough, if you dont mind spending and want to be doubly sure get the hylomar aerograde (pl32) its what the fly boys use as headgasket's (there a bit tighter on tolerance's)

rember the cleaner the better and change oil after a a couple of hours of running jsut to be sure.

[Disco_owner]

I would have thought if you lightly machine the heads then you'll have to get a different thickness steel shim gasket ? Also RAVE states to discard the Head Bolts and get new ones? although I know folks here have re-used the old head bolts without any issues?

[camel_landy]

The head gasket on the 300TDi is fairly straight forward but here's a few pointer for you...

Head Bolts
I was taught that they can be re-used (at the LR Technical Academy) but they should be checked first (run them through your fingers to check).

Push rods & caps
When you remove them, keep them all in order so that you can put them back where they came from.

Oil change
Make sure you've got all the bits needed to do an oil change too. When you pop the head off, no matter how well you drain the fluids, you'll be getting coolant in the oil!

Head skimming
Are you sure you need to do this? You're not supposed to skim the 300TDi head... Check it with a straight edge & if it doesn't need doing, don't do it!

Head gasket
There are 4x different thicknesses based on cylinder protrusion... Make sure you fit the correct one.

Valve Clearances
When you're checking the valve clearances, don't forget 'the rule of 9'.

HTH

M

[Tank]

If the head is flat, don't get it skimmed, IF you do you will need to get the valves seated deeper to avoid hitting the pistons, Regards Frank.