First time in the engine

Good morning everyone,

I am preparing to delve into my engine and thought I'd check in with some experts prior to messing it all up. First my questions...

Q1. a) How long should I allow myself to get the bits apart and get to a stage where I can see what's going on?
b) How long should it take to subsequently put back together (once parts are sourced)?

Q2. I am doing this on a drive with no specialist tools or kit. Is there anything that I am likely to be halted by?

Q3. Is it okay to leave the engine part dismantled for a few days whilst I source bits. Can I just cover the open engine with a tarp and weight it down or do I need to take more care of it whilst it's exposed to the elements?

My understanding is I need to be looking for some core things whilst in there, those being; cylinder head (cracked?), worn piston rings, head gasket knackered, valve stem seals had it. I'm guessing the last 3 I should replace anyway? I would still like to know what to inspect even if I am systematically replacing them as I like to test my limited knowledge and see if I can make sense of what has happened and why.

I was aiming to start this afternoon whilst we have some good weather here in the South. I just want to make sure I'm prepared for what lies ahead.

Thanks for your help and guidance. It's appreciated, as always.

Andy.

It usually take me around 2 hours to do a head gasket.

Ok, now let's start at the beginning... The cylinder head is the bit that sits on top of the engine. Before removing it, take off everything that is bolted or otherwise attached to it, i.e. manifolds, etc. You don't say if it is your S3 petrol or are you working on a doozil? If it's not a doozil, take off the fuel pipe stuff, and if it is take the injector pipes off the injector thingies.

Once that lot is off, take off the tinny bit that's held on with 3 nuts, and underneath that you wil find a shaft with 8 bits of wobbly things on it.

Before you take that off, get yourself a bit of cornfalkes packet and make some holes in it and number them 1 to 8. You will need that for the bits that come out at the back end of the rocker things. These are called 'push rods' and must go back in the same holes that they came out of.

When you start to undo the bolt thingies that hold the head on, refer to your manual for the tightening sequence - they usually show a picture - and take them off in the same order.

Once you have the head off, the valve stem oil seals are straight forward if you have a valve compression tool ... essential bit of kit!

You can then check the rings by putting your digit on the top of a piston and see id it wobbles. If it does, you will have to drop the sump to get the pistons out to replace the rings.

Always replace the head gasket after you have taken the head off. The full gasket set only costs a few quid, so it's worth doing.

If you are leaving the head off for a few days, get some bits of oily rag and stuff the cylinders with them, and give the mating surfaces of both the block and the head a smear of oil. Not only will that help to prevent a film of rust developing, it will also make it easier to put back together again!

Yes it's generally OK to cover it with a tarp, as long as you prevent any condensation forming underneath it!

You don't say if the engine is running or not. If it is running OK, don't do anything to it that you might regret later!

However, before doing anything RTFM.

Hope this helps.

Thanks Dog. I have read the manuals (Haynes and the generally more helpful LR Workshop Manuals) so I have a fair idea of the steps I need to tackle.

I don't have a valve compression tool so thanks for making a point of that. I'll definitely order one before I begin.

I suspect that I will need to get quite a few parts - if previous jobs on this car are an indicator - so I think it will be a non-runner for at least a week or two whilst I figure out what needs doing, order the parts and then put them back together. So it's useful to know how I can protect things against the elements so thanks for that also. I guess though, there is no reason why I can't stick the head back on whilst I wait for things so perhaps I won't need to leave 'the head off for a few days' and subsequently not have the worry of the elements getting into the engine.

How long does this job of dismantling and reassembling normally take? Is it fiddly, labour intensive or is it all quite straightforward once you've got the prep work done of removing manifold, fuel & cooling pipes etc? It's my petrol I'm working on by the way.

I understand that the worst case scenario (which I'm prepared for as my car seems to have been pretty unloved and unrepaired for a lot of the past 40 years!) is that the actual block is cracked. In which case I will need to replace the engine complete I presume. I'm thinking next worst is the head is cracked which will require a replacement head at a few hundred quid. Is all other stuff fairly manageable/cheap or are there still some other pretty terminal scenarios I could expect once I'm in there?

Sorry for the longwinded posts but I have a lot of questions. I have researched a fair bit and I believe a lot of my assumptions to be fairly accurate but there's nothing like someone who actually knows this stuff to straighten things out or confirm that I understand things correctly.

Thanks.

theres a brass bung on passenger side of block half way up nearer the front than back drain system there it stops coolant spilling into cylinders when heads undone, heads rarely crack ,bores unfrequent to,wear on bore willbe most evident at the top of ring swept area on passenger side ,mext to none at fore and aft sides of bore and reducing as you go down bore , valve guides are replaceable and cheap as are valves ,spray grease is what i use to protect bores etc if job standing,bore and ring wear is the most common problem on all 4 cylinders upto 200 tdi

What makes you think that the block may be cracked?

If you are losing coolant, have you checked that the core plugs are not rotted away and leaking?

You still havemn't said if the engine is runniing or not, as that would give some further clues before you start stripping it down.

Thank you James, most helpful in what I should be looking out for.

Dog, nothing makes me think the block is cracked. I am just offering my understanding of possible scenarios once I'm in there. Sorry for missing your question: The engine runs, though very ropey and been getting progressively worse over the last year. Compression results were WELL down, being 130psi, 66psi, 121psi & 137psi. I hope for my sake that it is a cheap and simple fix, but every other job done on it so far has become far more involved than originally the symptom may have indicated so I am just preparing myself to understand all of what I might be faced with.

Check your that valves are fully closing on the No 2 Cylinder, and gap your tappets.

If they are not seating you will get leakage through giving a misfire as the fuel wants to burn inside the manifold rather than in the cylinder.

Are you getting any pressure building up in the sump and blowing out of the oil filler cap?

Righto dog, I'll check those things first. How would I test for pressure build up in the sump? If I take the oil filler cap off with engine running then it puffs exhaust fumes out. I don't know if that helps diagnosis at all?

depends on amount ,taking off filler cap is how you check for crank case pressure ,but much shows rings/ bores blowing,valves arent opening fully ,head gasket ,i think i would want to remove head judging by compression reading as well

It puffs out like a miniature steam engine.

I always thought I would remove the head anyway as the car is an unknown to me and I'm gaining confidence in it by systematically familiarising myself with it all, knowing that once I put it all back together it should give me trouble free motoring for years to come. As oppose to only going as deep as seems minimally necessary, to find in 6 months I have to have it all off again to do a more thorough job of it anyway.

But, my own personal compulsions aside, it's nice to know that I am doing what seems like the right thing anyway by getting it off. Once it is off I think I will need a lot of questions answered as I won't know what tolerances are acceptable. I have found that one of the hardest things of having no experience. That is, when I look at a seal or whatever it is, I have know idea if it's state is acceptable or if it is a wonder that it's still doing any job at all.

Thanks so much for your help so far chaps. It's really appreciated.

Hi,

Liking the guidance on this thread! A quick question though - how can you tell if valves are closing proerly or not? By eye, or taking a measure?

Ta

What does your oil smell like? That's another clue ... If it smells of petrol/exhaust, then it sounds as though you might need to fit a new set of rings. Do them all, not just the one that's kaput.

In the Series I the bores had a thick chrome lining and were not really susceptable to wear, so it would be OK just to change the rings. For later models, I'm not sure if they were chromed or not, so over to James for further info.

Changing the rings is not difficult as you can lift the con rods and pistons through the top after removing the sump. Refit by dropping them back through the top, using a piston ring compressor or some old feeler gauges to guide the rings back into the cylinders.

I have to admit that when I did mine I renewed the pistons at the same time. A pleasant surprise was that the replacement pistons and a full set of rings were a lot cheaper than I thought they would be!

Mate,

You never told me if that alternator worked.

It would have been nice to know.

rxl123 said:

Hi,

Liking the guidance on this thread! A quick question though - how can you tell if valves are closing proerly or not? By eye, or taking a measure?

Ta

Click to expand...

If the the head is on the block all you can do is ensure there is a tappet clearance or do a leak down test (which is a little bit specialist)

If the head is off, just turn it upside down and pour petrol or paraffin in the chamber. Then wait for the leak or not.

300AJC said:

Mate,

You never told me if that alternator worked.

It would have been nice to know.

Click to expand...

Hello mate,

Sorry I never got back to you, I've had a number of priorities come up since you sent it and not been able to get it on. The vehicle's off the road now until I can get the head off - been waiting 6 weeks for this rain to stop and I'll finally start the job! Will let you know when I finally get it on and if it works.

Thanks again for sending it though, really very kind of you.

Water247 said:

Hello mate,

Sorry I never got back to you, I've had a number of priorities come up since you sent it and not been able to get it on. The vehicle's off the road now until I can get the head off - been waiting 6 weeks for this rain to stop and I'll finally start the job! Will let you know when I finally get it on and if it works.

Thanks again for sending it though, really very kind of you.

Click to expand...

Righto. Hope you're back on the road soon.

Can anyone point me to a VALVE COMPRESSION TOOL that will be good for the job on this 2.25 petrol engine? I want the cheapest possible whilst it still being fit for the job. Thanks.

if you buy cheap there's a very good chance the tool will flex before it gets to do any compressing

Hence asking for a recommendation for one that is 'cheapest possible whilst it still being fit for the job'.

Is it worth also buying a piston ring compressor tool or is it not too much bother to get the pistons back in without one?

Hoping that if we get another week of sunshine I will finally get this job under way.

Water247 said:

Hence asking for a recommendation for one that is 'cheapest possible whilst it still being fit for the job'.

Is it worth also buying a piston ring compressor tool or is it not too much bother to get the pistons back in without one?

Hoping that if we get another week of sunshine I will finally get this job under way.

Click to expand...

you do reallly need ring compressor to fit pistons back in ,it is pssible without but you run a big risk of breaking ring , i have a set like these and prefer them if fitting lots of pistons https://encrypted-tbn1.google.com/
images?q=tbn:ANd9GcQrYEIdG31zyPvDDe01E_k9a2A372qJxhlmegwU5MJiBUYYs2vW