325 head gasket change

Need technical Q/A then you're in the right place

Moderator: martauto

User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sun Feb 16, 2014 5:56 pm

Hi I am new to the site so bear with me, just got my first e30 325i touring that I have bought as a project. I haven't had time to properly check the head gasket as the previous owner said it had gone and I got it at a good price. Can anyone tell me how long it would take to change it or an approx price? I am in Manchester.
kam-325i
E30 Zone Team Member
E30 Zone Team Member
Posts: 4851
Joined: Tue Sep 27, 2005 11:00 pm
Location: TELFORD !!!! (Shropshire) Stevetigger Land !!!

Post Sun Feb 16, 2014 6:03 pm

Welcome to the Zone !!!

I did mine in around 4-6 hours, that included new cam belt, cam belt tensioner and water pump, Bleeding the cooling system afterwards was a bit of a pig.....
Pete don't care about colour, He would shag a rainbow if he could find the end of it....
Image
PG325
E30 Zone Camper
E30 Zone Camper
Posts: 1194
Joined: Sat Jun 06, 2009 11:00 pm

Post Sun Feb 16, 2014 6:09 pm

Just prey none of the manifold studs snap as this happened to me when I did the gasket, had to have it drill out in the end, and it meant the car was off the road for a week.
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sun Feb 16, 2014 6:24 pm

Ok thanks, I will be able to properly at Look at it tomorrow. Fortunately it will be my weekend toy!
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sun Feb 16, 2014 6:27 pm

Does anyone have an opinion on an induction kit and is it worth it?
Grrrmachine
E30 Zone Wiki / Team Member
E30 Zone Wiki / Team Member
Posts: 8043
Joined: Sat Feb 09, 2008 11:00 pm
Location: Warsaw, Poland

Post Sun Feb 16, 2014 8:07 pm

Be wary if someone tells you the HG has gone on a 325i. Unfortunately the heads on these engines are the weak point, and if the engine overheats the head will crack in the majority of cases.

If you're going to tear things apart to do the gasket, it's worth sending the head off to be pressure tested before refitting.

And no, an induction kit is not worth it at all.
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sun Feb 16, 2014 8:26 pm

Ok cheers
User avatar
Brianmoooore
E30 Zone Team Member
E30 Zone Team Member
Posts: 49360
Joined: Mon Jan 10, 2005 11:00 pm

Post Sun Feb 16, 2014 8:41 pm

What are the symptoms of this "blown head gasket?"
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sun Feb 16, 2014 8:45 pm

He has driven it 100 and odd miles and then checked the oil. He said it was creamy but not used any water ad might be condensation as it had been stood for a while before use??
User avatar
Brianmoooore
E30 Zone Team Member
E30 Zone Team Member
Posts: 49360
Joined: Mon Jan 10, 2005 11:00 pm

Post Sun Feb 16, 2014 8:58 pm

Get everything up to pressure and temperature, stop the engine, remove the rocker cover, and start the engine again.
Watch very carefully, at the bottom of the rear two cam bearings, to see if an occasional bead of water emerges, scuttles across the surface, and disappears down one of the drains.
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sun Feb 16, 2014 9:05 pm

Ok cheers will do. Would the condensation be a possibility?

If it's just a bit of mayonnaise on the end of the dipstick and under the oil filler cap, then it probably is, especially if the coolant level doesn't go down.
If the whole of the oil is turning to mayo., and the car uses coolant, then it's probably a crack.
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Mon Feb 17, 2014 10:36 pm

Right, got the car home today but didn't drive it just in case it was the head. Looked through all the receipts for the cr and puns the head was replaced with a full kit at just over 100k, it is now showing 153 with all the MOT s to back it up. How long are the heads meant to last??
User avatar
Brianmoooore
E30 Zone Team Member
E30 Zone Team Member
Posts: 49360
Joined: Mon Jan 10, 2005 11:00 pm

Post Tue Feb 18, 2014 12:35 am

Heads are meant to last for ever, but don't take kindly to overheating of any kind, airlocks, or the use of under strength corrosion inhibitor/antifreeze.
What is the oil like (level and colour), and the same for the coolant in the bottle. Correct level is supposed to be the seam half way up the tank, but a lot of E30s will settle at about 10mm below this level, which is absolutely fine.
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Tue Feb 18, 2014 8:17 am

On the filler cap and dipstick it was very discoloured. Didn't get home until late and it was dark so will check today. It has overheated at some point as there is another recirpt not that long ago saying investigate overheating problem. It seems to be running fine with plenty of power. But the coolant warning light is on and the check light also.
Grrrmachine
E30 Zone Wiki / Team Member
E30 Zone Wiki / Team Member
Posts: 8043
Joined: Sat Feb 09, 2008 11:00 pm
Location: Warsaw, Poland

Post Tue Feb 18, 2014 8:54 am

Do Brian's rocker-cover test to check for cracks. If you don't see the symptoms, do an oil and coolant change and drive it for a while. If the symptoms return, start looking for a new head.
User avatar
Brianmoooore
E30 Zone Team Member
E30 Zone Team Member
Posts: 49360
Joined: Mon Jan 10, 2005 11:00 pm

Post Tue Feb 18, 2014 10:01 am

What do the contents of the coolant tank look like? Does the coolant lamp stay off if the bottle is filled? Failure of the level sensor is common.
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Wed Feb 19, 2014 7:10 pm

Coolant level is all fine and the right mix. Coolant light has stayed on even tho some was added, also the washer light has stayed on and I have filled them up so must be a dodgy sensor? Oil level is correct.
User avatar
Brianmoooore
E30 Zone Team Member
E30 Zone Team Member
Posts: 49360
Joined: Mon Jan 10, 2005 11:00 pm

Post Wed Feb 19, 2014 8:12 pm

Check that the plug of the washer bottle is pointing upwards. It can be turned in the bottle (round hole) so can get turned on its side.
For the coolant sensor, unscrew it and check that it's not gunged up and sticking, check that the wires to the plug haven't cracked through right where they enter the plug, and then check that shorting the two pins of the plug together with a short piece of wire keeps the light off. The sensors eventually fail when coolant seeps into the centre stem and rots through the fine wires to a reed switch. New ones are readily available.
If the coolant is clean and maintains level, then I doubt if you have a cracked head.
Do a compression check on all six cylinders.
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sat Feb 22, 2014 11:39 am

Absolutely spot on with the washer sensor. Removed the coolant sensor and cleaned it but no joy. Very impressed with the help on the sure as this morning I have managed to fix my passenger electric window and rear wiper with no parts needed. Rear wash doesn't work though. What is the easiest way of changing the coolant?
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sat Mar 01, 2014 3:07 pm

Ok, changed the coolant and sensor and all is ok. Ran it half an hour and not used any water/coolant. What is the normal running temperature for the 325? Mine as sat at the 3 quarter point between the blue half way, is this right as I am changing the oil today also??
User avatar
Brianmoooore
E30 Zone Team Member
E30 Zone Team Member
Posts: 49360
Joined: Mon Jan 10, 2005 11:00 pm

Post Sat Mar 01, 2014 8:59 pm

Needle just slightly to the right of the line between the blue sector and the centre line is correct for a six cylinder E30, which is where I think you say it is.
For reference, on a four cylinder E30, the needle sits in the middle.
So, it sounds like you've got yourself a bargain - of all the 'problems' you listed, the only expense was a coolant level sensor.
Any cam belt history? Would be a pity if that let go and destroyed a good engine.
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sat Mar 01, 2014 9:23 pm

Nothing on the cambelt history, changed the oil today and took it on a 30 mile test drive. Filer cap was cleaned prior, slight discolouring when returned home. No coolant use and temp all ok. I think I will run it and see it what happens. Absolutely love this car! I can clearly see by the oil that's come out that it hasn't been looked after, shame about that because what a cracking car. Even if the head gasket has gone I will get it changed and keep it. MOT and tax and I picked it up at a really good price.
User avatar
Brianmoooore
E30 Zone Team Member
E30 Zone Team Member
Posts: 49360
Joined: Mon Jan 10, 2005 11:00 pm

Post Sat Mar 01, 2014 9:50 pm

Johnboy83 wrote:Nothing on the cambelt history,
Then get yourself a belt, tensioner pulley and water pump, and change it ASAP, unless you enjoy Russian roulette!
Steering, brake and clutch fluid changes should probably also be in the schedule.
£66 invested in having the injectors rebuilt should also be high on your list.
User avatar
Johnboy83
E30 Zone Newbie
E30 Zone Newbie
Posts: 50
Joined: Mon Jan 20, 2014 11:00 pm

Post Sun Mar 02, 2014 12:03 pm

Yeah will do. Do u recommend anyone to do the injectors? It will be going in for a full service and all fluids changed very soon. To be on the safe side the discs and pads are also going to be done.
User avatar
gooner1
Out humping Reindeer
Posts: 13280
Joined: Fri Apr 14, 2006 11:00 pm
Location: Northampton.For my sins.

Post Sun Mar 02, 2014 12:20 pm

Johnboy83 wrote:Yeah will do. Do u recommend anyone to do the injectors? It will be going in for a full service and all fluids changed very soon. To be on the safe side the discs and pads are also going to be done.

http://www.e30zone.net/modules.php?name ... c&t=152878
Image