head gasket help

[rpcee]

Hello,
Not sure I should have, but having many years ago owned am MG1600 'R' (WJH 489Y which I guess is long gone) I have on a whim bought for far too many £ an MG 2.0 EFi, only the head gasket and fuel filler pipe are both in need of a change.
Do I get the MG Montego Haynes manual to show me thru changing the gasket, and where on earth do I get the fuel filler pipe? There must be one in the country?
Actually I assume the head gasket is gone cos (a) the mechanic who is v. good says so, (b) there are air bubbles in the expansion tank, (c) one of the hoses pressurises v. quickly.
Also the heater doesn't work, which I read is possibly down to a faulty thermostat, but could this also be the hg? Would someone remove the thermostat to hide a hg problem? The temp. gauge reads low I hope this is why I got 23MPG on a run.
Cheers, Richard

[E_T_V]

Hi and welcome to the forum. Yes a haynes manual is available for the maestro 2 litre, which should take you fairly well through the process of changing the head gasket.

If you are getting bubbles in the coolant and also hoses are pressurising before they get hot then indeed it does sound like headgasket failure.
When the headgasket goes the heater usually goes on the blink too so I'd not worry about this too much yet.

The thermostat may have been removed to mask or help with the headgasket failure to prevent the car from airlocking and becoming overheated.

The fuel filler pipes may be available from a place nicknamed "ledbury" If you do a forum search on it you'll find the details however he doesn't post them. (The contact details are on a "sticky" thread in the recommended link section). The fuel filler pipe is a common problem as they rot through. If you are really stuck then someone on here may have a spare one or you may be able to get one made or your old one repaired.

If you need more help then please ask and we'll do our best!

[rpcee]

I'm sure I will be back - I only changed one head gasket before and that was a 1979 Escort OHV, which I am told is as simple as it gets. I'm a programmer by trade and not used to real objects that make your hands dirty rather than just give you invisible RSI, but just can't face adding mostly labour costs to something I already overspent on - was wondering whether to cut my losses and sell it on or what. Fortunately still have my trusty 309 so no rush to fix the MG.
I could only find one Maestro Haynes manual which says it doesn' cover the MG 2.0 EFi so assumed the Montego 2.0 Petrol one would cover the engine - is that right? I've a funny feeling my old Maestro manual chucked on the bonfire last year as I'd "never need that again".
I'll try Ledbury tomorrow, many thanks.
I'm assuming that most parts are easy to come by - water pumps/alternators etc, and it's the Rover specific body parts that are getting rarer - is that a good assumption?
Thanks

[E_T_V]

Yes your assumptions are pretty much spot on most service items are pretty easy but some bodypanels are tricky. Yes you will indeed need the montego manual (which covers the EFI), rather than a meastro one, (sorry my grey matter is slowing down tonight).

The headgasket is pretty easily changed in a weekend, (worth changing the cam belt at the same time) and as you say it is labour costs rather than any other costs that would make it expensive to have fixed at a garage.

When it is running right you'll be impressed I'm sure, and you'll see a lot better mpg too!

[rpcee]

I did enjoy the drive home in it, I guess with a rich fuel mixture it was quite nippy, but also thankfully no bearing type noises, brakes working fine and very fluid round the country lanes, so I'm hoping the rest of the car is not the equivalent of the engine. Also must admit I'm looking forward to doing the HG, although a little nervous.
Anyway my next more general question is that my torque wrench has been unused for some years, 7+, and kept in a fairly damp shed (seems to rain here in Wales), it's a Sykes Pick... so was of reasonable quality but should I now play safe & get a new one, or assume if it "clicks" easily on low settings it is still reasonably accurate? Apologies I don't know the right terminology.
Richard

[rpcee]

Thanks, Ledbury do have a filler pipe @£15 but I found a personal visit to the local rover dealer (only 30miles away) yielded one so forked out £50 for that.
Decided to cheat on the gasket, the mechanic will do it, as the car is 120 miles from me so I'm not sure I might do more damage driving it that far. Next time maybe.

[rpcee]

another change of mind, mechanic reckons I can get it home to do the hg myself. Is there any particular brand of gasket i should ask for, and what's the opinion on use of gasket sealant stuff?
Also do I need to buy new bolts?
Has anyone ever made a photographic record of doing a head gasket/timing belt I could look through online? If i remember correctly the Haynes manuals always have non obvious bits in.
Thanks, Richard.

[E_T_V]

The haynes is pretty straightforward. The only tool you'll need that you might not have is a torque wrench. The head bolts are re-usable just oil them with light oil before replacing them. Any aftermarket gasket set will do or you can probably still get them from rover too. Payen are a reputable gasket maker but I've used all sorts before now with no probs yet.

Don't use any gasket sealant on the head gasket itself unless is specifically asks for it.

[rpcee]

Should have the car fairly soon - end of week. I need to drive it with headgasket gone for 100 miles, also the radiator leaks. I assume it would be a bad idea to add radweld with a broken HG. Would the extra pressure cause the rad leak? Is 100m too far to risk? (Obviously many water check stops but it's very rural route - no traffic jams but long distances between towns and lovely steep hills).
Many thanks.
Also are radiators freely available?

[E_T_V]

Yes radiators are freely available. Yes it is usually a bad idea to drive a car with a blown head gasket. If it is mixing oil and water together then don't drive it let alone 100 miles. If it is just loosing water into the cylinders then so long as you can prevent it from overheating you might get away with it.

[rpcee]

managed the trip, used some water but didn't have to top up, radiator doesn't seem to be leaking and car still sounds sweet as a nut and I can't see bubbles is the expansion tank anymore, I smell fishy red herrings. Temp. gauge still v. low and idling seems to be anywhere between 600 and 1400 rpm - not hunting up and down but one time you stop it's 1400, drive a few miles, stop, it's 1000, etc
Still, least it's home & doesn't need to go anywhere til I know more.

[rpcee]

Just did a compression test - from left to right (is that 1 to 4 or 4 to 1?) I got 120psi, 150, 150, 160 which according to what I read means a fault.
The leftmost thread wasn't in too great condition, but I think it sealed OK.
What's the best way of cleaning the thread up as best as possible? I guess once the cylinder head is off makes it easier.
Also when I removed the plugs, the gap was rather wide (over 1mm) and plugs somewhat carbonised apart from the end of the earth electrode which was basically clean (removed while engine hot), which according to Haynes means over rich fuel mixture (though in their picture the whole of the electrode is black), but I guess I don't worry about that til the HG done.

[E_T_V]

If the spark plug thread is damaged this can cause your low pressure reading. There are two ways that may fix it. The first is a thread chaser. Basically this is similar to a tap to re-tap the thread but it cleans out any debris etc. It won't help if the thread is badly damaged however. If this is the case then you'll need to helicoil the thread when the cylinder ehad is off. This isn't usually terrible expensive and is well worth doing whilst the head is off for its gasket replacement if it looks dodgy. I think they are usually about 20 quid to do. I had to have one done on my motorbike once and it lasted just fine.

[elj737]

I had a similar issue with a plug therad and used a thread chaser (Halfords?) which was about £10. You just screw it in and it cleans the thread and should help the plug reseal.

Regarding the 'headgasket' issue, perhaps it is an airlock in the system ?

[E_T_V]

The air lock is preventing the heater from working, as air (well combustion gases really) are entering the coolant and sitting int he heater matrix.

This is one of the final signs of headgasket failure in the perkins. The first is pressurised hoses. Then if the pressure is left overnight in the tank the car starts using a little water. Then the heater goes cold. Then you start using a lot of water!