Thread: Head off/New Head Gasket Coming/Anything Else?

any help is greatly appreciated.

Cheers in advance!

The engine has used excessive oil and the valves were covered in oil when I dropped them off a the engineers yesterday. He reckons new valve oil seals will fix the oil getting past the valves.......

Do you guys think I should drop the pistons while I've got the head off to have a look at the rings? My guess is that I would need to replace them.....

Cheers,
Neo

If you think rings might be the problem, you'd be wise to attend to that whilst you're in the guts of it, and before it becomes less of a problem and more of a fail to proceed.

Originally Posted by neophyteguy

I've got a few queries and would appreciate any help you can offer as this is my first "head off" experience.

- Does the new VRS head gasket (from ALL 4x4) require any type of sealant?
Not sure but all of the head gaskets I have used in the last 35 years were assembled dry. Most important of all is install the right way around.
-Is it best to put the manifolds together before mounting them on the head, or to put the exhaust manifold on and then the input manifold?
You should be able to put them on afterwards with not much hassle which will make it lighter to lift.
-I didn't really specify it, but would you reckon the head will now be "unleaded friendly"?

It was from the factory so don't worry about it.

-As I was pulling out the head bolts, I didn't pay any attention to which bolts came from where. I'm sure I'll figure it out, but does anyone have a general quid as to where the different size bolts go? DOH!

-Is it ok to clean the top of the pistons while the heads are off or should I just leave them alone? If so, what's the best way to clean them?
Use a piece of hardwood cut at 90 degrees on the end as a scraper. when it gets blunt re-cut it with a carbide saw.
-Is there a gasket between the bottom of the exhaust manifold and the top of the pipe? (Where the pipe meets the manifold-triangular fitting)
It depends on which exhaust you have but from your description it is the conical fitting which doesn't need a gasket. Use a smear of high-temp silicone on it for a guaranteed seal.
I'm really hoping this freshen up will sort out some of the issues I have with burning oil, but not really sure. Either way, I'm sure it will run better than before.....The valves were completely covered in oil, so the machinist is sure I'll have a decrease in oil use--hehe

Neo

Give the pistons a good shake with your thumbs when they are at TDC - if there is appreciable movement, it probably needs new rings. If there is a prominent ridge at the top of the bore, it probably needs re-boring. A reconditioned long-engine with new parts and gaskets etc. will cost about $2500 unassembled, depending on what work needs doing.

For the head work; examine all of the fasteners and discard any that are damaged or rust-pitted. Clean the male and female threads before assembly. Use a tension wrench on the fasteners with the head bolts lightly oiled. I usually use Loctite 243 on the manifold fasteners. Make sure that all of the manifold faces are completely flat and the corresponding head faces - quite often there are raised lumps around the female threads.

Get the rocker gear examined as well; check for worn bushes and shaft and wear on the rocker arm faces - replace or re-condition.

Treat the machine to some new coolant hoses when you glue it together again - good luck and have fun

Cheers Charlie

Thanks guys, I appreciate the replies!

I'm not getting much movement from the pistons, but still wondering if perhaps the "scraper" ring isn't right in one or more pistons.

The pistons are marked as:

1B
2A
3D
4D

The engine has not been re-bored according to the piston sizes.

--DOES ANYONE KNOW HOW TO ORDER RINGS FOR A STANDARD OEM PISTON?

--There is certainly a ridge large enough to catch my fingernail on in each of the pistons. I've read that if new rings are put on, they'll break off on the ridge? If I only replaced the other "rings" and left the top one one (assuming there ok), would this get around the issue?

--Can a machine shop come up with rings or is this a land rover only item?

Thanks again!
Neo

Sounds like it might really be worth your while to get yourself a Series Land Rover Repair Operation Manual (or at the very least a Haynes). And there are a number of vendors on this forum who can supply any and all OEM or NOS parts. For me, it has been a very big help getting to know my local Land Rover parts and service outlet, too.

Thanks Gary!

I've got the green bible, the original LR manuals and a few others. I guess my question really is more around whether or not I can simply buy new rings and put them on but:

-Will the lip break the new ring

-Can I simply replace the lower rings so the top one doesn't break off (if the lip is an issue)

I've got to take the sump off to replace the seal any ways, so I'm going to be most of the way there as the head is already off. What I don't have time/$ to do at the moment is to take the entire engine out and then have it bored.

If it's simply a matter of pulling the pistons and putting in new rings while I've got the head off then I'll be pulling things apart today.........

Thanks again everyone
Neo

Neo,
If you can catch your nail under the ridge, then the cylinder bore needs measuring with an internal micrometer to see if it has worn past its upper tolerance. If it is too worn it is re-bore time - fitting rings to an oversize, out-of-round bore, doesn't work for long.

If the bore is still within tolerance new rings can be fitted; however; the bores will need honing and the rings should have a stepped-ring in the top piston groove. Repco used to make them and probably still do. Ideally the ridge should be removed. Before you decide what to do, clean the bores with a clean rag and look for scoring on the cylinder walls; excessive glazing (shininess) or any other nasty defects. If any exist the engine has to come apart.

My advice is to strip the complete engine; get someone to measure the bores if you don't have a micrometer; measure the crankshaft and inspect it for scoring where the seal runs; inspect the camshaft and rollers (keeping everything in order) and get a quote to have everything re-conditioned.

Remember, that there is little point in fixing only one part of an engine, as it works at its best when everything is in perfect condition and adjustment, so check everything.

Cheap engine parts can be bought from the UK, but I can't vouch for the quality. ACL are good quality parts, which your engine re-conditioner will be familiar with,

Cheers Charlie