E46 cracked head?

[Corey6]

Greetings fellow beamer lovers. Bought an 03 e46 320ci and i think the head or block may be cracked. I have no smoke out of the exhaust but bubbling in the expansion tank and overheating. I put more coolant in and it drinks it then it begins to push the coolant up the expansion tank? Ive ran some steel seal through it today and ill see how it is tomorrow morning. Any idea if its a cracked block or a failed head gasket?

Cheers

[Corey6]

EDIT: no water in oil and no oil in water either. Running perfect with no misfires.

[helix402]

Blocks don’t crack on these. What does happen is that if you put a new head gasket on the the threads often pull out of the block as you tighten the new head bolts (40Nm followed by 90 degs off the top of my head).

I guess you bought the car you asked for advice about buying? You could use a block tester to check for presence of exhaust gases in the coolant.

[anonymous-user]

It's buying a sniffer kit that checks for hydrocarbon gasses in the cooling system

Or take it to a garage and have them do it.

If there is then its worth getting a compression test done

Usually with a cracked block you will get water loss

If its HGF then the exhaust gasses can be forced into a cooling gallery and pressurise the cooling system.

Id does sound like HGF between a cylinder and a water gallery to me.

[Corey6]

Aye i did, just couldnt resist and for 450 you cant go wrong. It could be the head bolts need re-tightning. It'll be going in for a compression soon anyway so ill ask about a sniff test. Hopefully the steel seal will solve the problem....

[anonymous-user]

Corey6 said:

Aye i did, just couldnt resist and for 450 you cant go wrong. It could be the head bolts need re-tightning. It'll be going in for a compression soon anyway so ill ask about a sniff test. Hopefully the steel seal will solve the problem....

Don't do it..
You might find that the head has warped as a result of the car overheating in which case the head is scrap.
If so, when the heads warp they will pull the head studs from the block, the block will need heli coiling, you will need a new head and new head studs.

Really should have avoided this one imo.

[helix402]

The problem won’t be due to loose head bolts, unless the old ones have damaged threads-in which case you’re back to the problem mentioned earlier. The blocks can warp on the M54 in addition to the heads.

[Corey6]

Youre probably right, but im selling my old car to fix this one up so i dont mind spending a few hundred on it or even 1k. To me its still a bargain. So i wont get the bolts re tightened if thats going to cause more damage. Ill see how the steel seal is tomorrow and hopefully ill see results. I spoke to the previous owner and he said he's never ran the car while its been above optimum temp so i dont think that'll be a problem. Maybe the waterpump isnt circulating the coolant which has resulted in head gasket failure?

[Mr2Mike]

They will be torque to yield bolts anyway so not possible to tighten them any further.
Attemps to do so will just stretch the bolts further, (or quite likely pull the threads out of the block even further).

[dhutch]

I guess if it's a tidy car, for under £500, that's worth £1500 or so fixed, you have a budget to put it right if you're interested in a bit of a project.

I have a x-reg 330ci and it's lovely. 154k on the clock, very at home on the motorway and good fun on the lanes.

Daniel

[Corey6]

Its a super tidy car. It'd be worth loads more if the head gasket was fine but it was just a steal and the lad wanted rid of it, hopefully it all goes to plan, even better if this steel seal works haha.

[Sardonicus]

Dont bother with block seal remedies its a BMW engine not a 1930's Ford model A one, agree with previous advice i'm afraid

[Corey6]

Too late, ive ran the steel seal through it yesterday and she's working spot on today, no bubbles, not over heating and driving as smooth as ever. Maybe it was jist a hairline crack in the head but its solved the problem now.

[anonymous-user]

Corey6 said:

Too late, ive ran the steel seal through it yesterday and she's working spot on today, no bubbles, not over heating and driving as smooth as ever. Maybe it was jist a hairline crack in the head but its solved the problem now.

Well done, cheap motoring.

This is the type of car/problem/price point that this stuff was designed for.

Bot of advice - run it for a couple of weeks then have a coolant flush and change. If you leave it in there's a chance it may start to clog cooling lines and water pump.

it's worth £50 to get this done and you will be good to go.

[dhutch]

Fair enough. Always interesting to hear when these things work. Hopefully it lasts, keep us posted!

Daniel

[Corey6]

Will do. Ive took her out for a good run today and all seems fine

[iSore]

Steel Seal does work on the M52/4, seen a few that have been rescued with it. It beats changing an engine. The 2.2 isn't the best thing - they can really hammer though some oil and it's surprising how many have been replaced with 2.5's - a direct swap, better engine and a fair bit more poke.

[Corey6]

I think it'll be something ill do later on, at the moment im just waiting to shift my old car and get some cash behind me for a new exhaust, coilovers ect. I was tempted for a 3 litre swap but the petrol would be far too much to justify the swap as im a student anyway. Just curious, can you remap the ECU of the e46 in anyway? Im not sure on these.

[anonymous-user]

Corey6 said:

I think it'll be something ill do later on, at the moment im just waiting to shift my old car and get some cash behind me for a new exhaust, coilovers ect. I was tempted for a 3 litre swap but the petrol would be far too much to justify the swap as im a student anyway. Just curious, can you remap the ECU of the e46 in anyway? Im not sure on these.

The fuel and oil consumption difference of all 6 cylinder m54 engines really is marginal anyway.

[dhutch]

Yeah, when looked into it there was very little between the 330 and 325 on mpg.

Mine tends to stick at 31mpg mixed us, I can see 38 on a long run certainly if there is a 50mph roadworks. Can't maintain less then 22ish even if trying!


Daniel