Replace head gasket or...

E28 technical advice asked and given! Troubleshooting, modifications and more.
Post Reply
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Replace head gasket or...

Post by 1st 5er »

...swap out motors from parts car.

Here's the why.
:x Found chocolate shit in my eta's coolant bottle and on the dipstick. :x

I've also been wanting to do a 5 speed swap into this car,
but have been putting it off until slushbox failure,
but that didn't happen, this did.

The two options I'm considering:
1- change motors and do the 5 speed swap all at once
or
2 - head gasket replacement and leave all else as is.

If I go with option 1,
what are you thoughts as to what I should do to the other motor before installing,
other than the water pump, the timing belt and associated parts?
All I know about the other motor is that it ran when we pulled it.
Don't know the mileage,
but IIRC the broken odometer showed 198K and came without any service records,
so not certain of internal condition.

Thanks for any and all comments.

Looks like the E12 goes back into service without getting to the body work.
turbodan
Posts: 9223
Joined: Jan 09, 2007 10:19 PM

Post by turbodan »

Does the engine use coolant? Does it overpressurize the cooling system when running?

I wouldn't condemn anything just because of some doo doo is the expansion tank.
johnnye23
Posts: 5059
Joined: Sep 27, 2006 3:47 PM
Location: Auburn Ca
Contact:

Post by johnnye23 »

I am with Dan on this.Get a test kit from the auto parts store and confirm a head gasket failure. If confirmed I would do the entire engine/5 speed swap and be done with it . ;)
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

turbodan wrote:Does the engine use coolant? Does it overpressurize the cooling system when running?

I wouldn't condemn anything just because of some doo doo is the expansion tank.
Yes, uses coolant without visible leaks or tell tale smells anywhere.

Don't think it overpressurizes, the car still runs at normal operating temps and has not overheated.

The doo doo is also on the dipstick.

How and/or where else does water and oil have the opportunity to mix?
nnarth212
Posts: 1953
Joined: Aug 10, 2009 6:06 PM
Location: San Francisco

Post by nnarth212 »

Under the oil fill cap-- or you can remove the valve cover.


The head gasket is not difficult to replace with a bit of help.

WELCOME TO
Image

... I just left there.... new gasket, happy motor.
turbodan
Posts: 9223
Joined: Jan 09, 2007 10:19 PM

Post by turbodan »

swatterssr wrote:[Yes, uses coolant without visible leaks or tell tale smells anywhere.

Don't think it overpressurizes, the car still runs at normal operating temps and has not overheated.

The doo doo is also on the dipstick.

How and/or where else does water and oil have the opportunity to mix?
The oil passages of the M20 make it much less likely to mix water and oil than an M30. The oil feed and drain passages all go through the HG right next to head bolts and pretty far away from any coolant. Its a lot more likely to be burning it or leaking it externally than for it to be mixing fluids internally.

If you've got another motor and a 5 speed that can go in, I'd probably just go with that. You could have a bad HG or a cracked head. I've blown the hell out of some M20 head gaskets and I've only had water in the oil once the heads actually crack. Anything is possible, but if I were you I'd just do the motor swap and run it.
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

That's kinda the way I was leaning, go ahead and do the complete swap.

Do you think it necessary, based on the info I've presented, which is all I know, to do a top end job on the replacement motor before swapping?

OR

On what information would you make that call?
Should I do a compression test, etc. to make that determination?
turbodan
Posts: 9223
Joined: Jan 09, 2007 10:19 PM

Post by turbodan »

I dont think a compression test will help you here. If the gasket were blown like that it would be overpressurizing the cooling system and constantly purging.

I can't say for sure which way you should go without actually looking at the car. Just to be sure, you could try taking it for a good long drive to get it nice and warm and do a hot oil change to remove any residual moisture from the crankcase. If it still has any chocolate milkshake on the dipstick after that it would be a bad sign.

What kind of driving do you do with the car? What is the duration of your average trip?
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

turbodan wrote:I dont think a compression test will help you here. If the gasket were blown like that it would be overpressurizing the cooling system and constantly purging.

I can't say for sure which way you should go without actually looking at the car. Just to be sure, you could try taking it for a good long drive to get it nice and warm and do a hot oil change to remove any residual moisture from the crankcase. If it still has any chocolate milkshake on the dipstick after that it would be a bad sign.

What kind of driving do you do with the car? What is the duration of your average trip?
Casual city driving.
Can't get too spirited in an eta automatic.
My wife had been driving it daily up until about 3 weeks ago when we got the touring.
Her commute is about 5 miles each way, and then occasional trips to the store, etc.
These trips usually not more than 5 or 6 miles each way.
I've been daily driving it since the touring purchase.
My daily driving averages close to 60 miles per day, both city and highway.

We've made many road trips in this car over the last several years including a 2,361 miler to '09 5erFest.

The only unusual thing that has happened lately, is the fan clutch failed in the locked up position.
This of course caused no overheating, just loud whirring when in the upper RPM.
I happened to have a brand new one on the shelf that I replaced it with immediately.
That was back on the 8th of this month.
An interesting note here; the temp gauge had always been running almost straight up until this fan clutch failure.
Now for the last 2 weeks after changing the fan clutch the temp gauge never made it even near the center, it stayed about halfway between far left and center gauge.

The only other mechanical change was the installation of my new 8mm Red wires along with a new cap and rotor.

I'm guessing there is no way to differentiate between a blown head gasket and a cracked head without pulling the head.

Do I change the oil and flush the cooling system prior to this "good long drive to get it nice and warm"?
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

Alright guys and gals...

It's been 2 1/2 weeks and it looks like it worked.

No oil in the coolant and no coolant in the oil.
Check out the temp gauge.
DD'ing 60 + miles per day in H'town traffic,
including sitting on the freeway during the afternoon commute,
this is pretty much where it stays.

How long it'll hold up, :dunno: .
But hey, about $25.00 out of pocket for the Prestone Super Cleaner, Bar's Leak product pictured, and coolant,
and a couple of hours of rather easy work,
I'm not complaining.

Image
Image

Why would anyone "hate" M20s?
Son of a
Posts: 2366
Joined: Jul 17, 2007 8:50 PM
Location: Housatonic, MA

Post by Son of a »

swatterssr wrote:Why would anyone "hate" M20s?
Sherman, I have no idea. Don't get me wrong, I love my M30, but when it comes to absorbing abuse and still being easily repaired, nothing made by BMW beats an M20. My family has well over 1 million aggregate miles (and counting) on M20-powered vehicles and zero HG/head/valve issues.

You put power to an M20 that was running when parked, and barring rodent damage or other "active" destruction during its years* of being decommissioned, you can get it running for less $100 in parts and an afternoon. If it costs you anything at all. To truly destroy an M20 takes either work, a piling of massive neglect, or pure idiocy.


*I used "years" intentionally. The Grape has sat for at least 3 years and still starts and runs with a fresh battery. Heck, the day we finally hold its funeral (probably this summer) I imagine we'll get it running again just for old-times sake.
ElGuappo
Posts: 8130
Joined: Feb 12, 2006 12:00 PM
Location: Sacramento, CA
Contact:

Post by ElGuappo »

hmmmm, interesting.

I have an m20 e34 that my ex drives that has developed oil in the coolant recently but still drives fine, I was getting ready to do a HG (again-put an unknown but seemingly good head on from a friend when car was purchased last year) this car drives ~100 miles/day.

I guess this is a cheap test, I jsut HATE bleeding the e34 m20 cooling system. Easily the WORST/HARDEST to bleed cooling system BMW ever made.
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

Our, new to us, 95 E34 M50 Touring, bled pretty easily through the bleeder screw next to the coolant overflow tank on the side of the radiator.
It seems simpler than the E28.

I followed the instructions to the tee on the Bar's Leak Seal bottle.
Being able to use the block drain during the flushing and then the drying, for the 12 - 24 hours after the treatment, I'm sure helps it dry out inside the block for the sealant to set up.

I'm very pleased with the results.
I did no diagnostic work to determine cause of the seepage.
I just know it was going both ways,
and now it goes neither. :alright:
ElGuappo
Posts: 8130
Joined: Feb 12, 2006 12:00 PM
Location: Sacramento, CA
Contact:

Post by ElGuappo »

The M50 IS far easier to bleed than the later M20's. You essentially have to pressurize the coolant res to have ANY chance of bleeding it, then bleed at BOTH the rad bleed screw AND the thermostat bleed screw.

I made a perssure cap from a hollowed out rad cap sealed with silicone, a threaded fitting to a screw down pressure valve to dial down the air pressure, then just hook up the compressor and put in about 10psi and away we go...
Slaytanic-666
Posts: 861
Joined: Oct 05, 2008 1:42 AM
Location: Van Isle, BC, Canada

Post by Slaytanic-666 »

I beg to differ on the bleeding of air out of the coolant sys. on my 83 528e M20 it's as simple as the bleeder screw letting it run out (until no more bubbles) with catch pan under neath, it doesn't get any simpler than that. :banana:
a
Posts: 12473
Joined: Feb 12, 2006 12:00 PM
Location: Marshfield ,MA

Post by a »

I bleed through the upper aux fan switch. Never had any trouble.
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

OK, here's the update, preceded by the original symptoms.

Initially had water in oil & oil in the water & was losing water,
so had to refill coolant overflow about every other day.

After the previously mentioned fix, (I didn't think it'd be permanent)
here's the current symptoms;
Absolutely no water in the oil.
Slight amount of oil in the water.
Still losing water, but now it's like weekly that the coolant warning light comes on.
No overheating, needle never gets past 2/3 to the middle mark.

I've not pulled the head to check for failure point,
and probably won't.

I'm going to do the complete engine and 5 speed swap at the same time,
but hate to do all that work while the autotragic is still working fine and the motor is still providing 100% reliability on a DD basis.

Any thoughts or comments on that part of the scenario would not go on deaf ears,

but,

the real question is,

do I use the M20 out of my US 528e parts car, VIN - 9655200
or :dunno:
the Euro 525e 5 speed donor's M20, VIN - 1113730?

(Will this Euro M20 run on 87 octane or must it have 90+?)
Not sure of exact mileage of either,
but will replace timing belt and head gasket on either before installation.

Thanks in advance for taking the time to read and respond. :D
a
Posts: 12473
Joined: Feb 12, 2006 12:00 PM
Location: Marshfield ,MA

Post by a »

Ive had a 265 trans and stuff from an 82 528e waiting in the wings for a 5 spd conversion. FOR 10 YRS :rofl: The darn 4 HP 22s refuse to die. :cry:
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

a wrote:Ive had a 265 trans and stuff from an 82 528e waiting in the wings for a 5 spd conversion. FOR 10 YRS :rofl: The darn 4 HP 22s refuse to die. :cry:
That's what I'm thinking too...

But, I really want to be able to drive this eta more than 'just around town',
and I'm not really confident in the head and/or headgasket holding up to an extended trip.
Not necessarily a V@V / RTT style road trip but at least in the 200 + range.
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

Update...

I stopped the coolant into the oil, but not all the oil into the coolant issue.
But, while driving about a month ago the fairly new upper radiator hose burst.
It literally ripped from almost end to end.
Not sure how or why but guessing the gasket finally totally gave up the ghost allowing combustion gas into the cooling system.

Earlier in the year I picked up a rebuilt eta head, along with a bunch of other "packrat" stuff,
and this past week got the additional necessary hardware to complete the task
of head and gasket replacement.

Hopefully this exercise will put this thread to rest.


Edited to add "hose". See bold type above.
Last edited by 1st 5er on Nov 30, 2010 11:33 AM, edited 1 time in total.
Lucas_Roehr
Posts: 1139
Joined: Nov 06, 2008 2:56 PM
Location: Sacramento, CA

Post by Lucas_Roehr »

swatterssr wrote:Update...

I stopped the coolant into the oil, but not all the oil into the coolant issue.
But, while driving about a month ago the fairly new upper radiator burst.
It literally ripped from almost end to end.
Not sure how or why but guessing the gasket finally totally gave up the ghost allowing combustion gas into the cooling system.

Earlier in the year I picked up a rebuilt eta head, along with a bunch of other "packrat" stuff,
and this past week got the additional necessary hardware to complete the task
of head and gasket replacement.

Hopefully this exercise will put this thread to rest.
No, dont do it!! Dump everything and replace everything you want or you will never do it!! At least hear me out on this one. Losing a timing chain may have been the best thing that ever happened to my white e28. I pulled the entire thing out, cleaned ALL of the grease and oil off of virtually everything, put one new gasket on virtually everything including the transmission input/ output/ shift rod seals, and bolted a good head on everything that was already there. Doesn't drip a drop, doesn't consume a thing. In 3500 miles since I changed the oil last the level is still well above the 3/4 mark.

I put together a 528e that I wanted to swap a 5 speed in, and never did swap it, and regretted even past the day I sold it (sold it to a buddy who has all the parts but STILL hasn't done it yet).

I'm also currently putting together a former 533i slusher car in the same way as my dd 535i (bolting a nice refreshed head on a used block). I considered leaving the slushbox when I disassembled it, and kept track of everything as if it would go back in. After it was apart for a minute I considered what happened to my 528 and figured if it wasn't now it would never happen. As of Sunday my b34 powered 533 purrs with motronic from an 87 (not as nice as m1.3 would have purred :bawl:), and needs one more solid day of work to have the tab welded in place for the shifter linkage, and get the pedal brackets, etc., sorted out.

It's a lot more work than just doing a head gasket. But if you dump everything out all at once you have the chance to do it all one time. If money is not a constraint, then I vote e2i swap, manual swap, and 3.46 or 3.73. If you are trying to watch expenses then I guess just bolt the head on. It is nice for me to know that both my 84 and 86 e28s have drier engine bays than a lot of people's 04 and 06 vehicles. If you aren't inspired to scrub and reseal the entire drivetrain yet, maybe I need to post some pictures of how dry my two resealed cars are. :dunno:

I guess all that I am trying to point out in all of this rambling is that if I hadn't jumped some teeth on the t-chain, I probably would have put off all of the other seeps and drips that was making me add a gallon of coolant a week, a quart of oil ever 2500-3000 miles, and dripping gear oil all over. I just bought the 533 that I am rambling of, and it will be very nice knowing where most of the components are in there life expectancy. So do everything now so you can be done with it.
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

I appreciate the tip, and would do it if there were any other issues.

Earlier in the year the 5 speed swap was done.
I'm really not interested in more power out of this car, thus not doing the e2i swap.
I prefer the economy over the power increase.
I've got other "funner" cars...
The motor is tight and doesn't, or at least didn't, drip a drop of anything anywhere.

Money isn't part of the equation, but expediency is.

Thanks again for the comment, as that is the right way to proceed, in most cases.
shagrath
Posts: 14980
Joined: Jun 15, 2009 12:21 PM
Location: pLace

Post by shagrath »

Sherman I sent PM. :D
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

shagrath wrote:Sherman I sent PM. :D
It's next.
Lucas_Roehr
Posts: 1139
Joined: Nov 06, 2008 2:56 PM
Location: Sacramento, CA

Post by Lucas_Roehr »

hmm... I guess I should have noted the red 5 Speed in your signature. Ok, well then yeah, put a damn end to this thing. :lol:

Gathering all the parts in advance is definitely the smoothest way to replace a head gasket. Remove one cylinder head. Install one cylinder head. No down time or unexpected surprises at the machine shop. Have fun with the r&r.
1st 5er
Posts: 21865
Joined: Jun 13, 2008 12:15 AM
Location: Cypress
Contact:

Post by 1st 5er »

She's all buttoned back up.
Had to install a new radiator, plastic crap...
Post Reply