Head Gasket Issues

[colin evans]

Hi All
I haven't posted on here for a very long time as my 280SL has behaved itself for a few years! I need some help now as I am stumped, I will lay out all the details of what has happened.
I started the car one day and it hydraulicked quite sharply, then started ok. I was only fettling it so didn't drive it out that day. Next time out, I got a mile down the road and the temp gauge kept rising (it always settled at 180 before). I turned around and made it home in 5 mins but with a very hot engine. It was smoking white a little, but it always had done that a bit. I assumed it was the head gasket gone.
I stripped it down and had the head skimmed by a reliable local business and I fitted a new gasket (it took 2 attempts as the supplier sent the wrong one first time and stupidly I didn't notice until it was back together and water started coming out of the plug holes when I refilled the coolant. I got the correct gasket and torqued the head to 65 ft lb cold with new bolts. I never measured the head as my car is a genuine 50,000 miler and I made the assumption that it hadn't been done before.
It still smoked white more than I expected, but I drove around 10 miles fine with no overheating issues, although it seemed harder to start, which I put down to timing, I had somehow messed up the distributor position and had a big misfire on the first start up attempt. Once I corrected this it started and ran ok.
A couple of weeks later I took it to the local Merc garage around 8 miles away for MOT and to check the timing, which they adjusted. It ran ok on the way home but didn't idle as evenly as before and it white smoked at idle. By the time I got back there were clouds of white smoke at idle. I waited a couple of days and tried some K seal as a desperate measure but that seemed to be ineffective. I drove it down the road yesterday and noticed a loss of power, quite severe. I took the rocker cover off and there was mayonnaise everywhere. I retorqued the head to 80 ft lb warm after reading this forum but it when I started it back up it struggled to run and still smoked.
My thoughts are (and I am only an enthusiast not in any way a mechanic so please go easy on me!)
-Head was skimmed before so it is now under the minimum measurement
-Cracked head
-Cracked block
Is there anything else I should consider before I strip it down again to investigate? I did read somewhere that a porous inlet manifold could create the same symptoms, but it seems unlikely? My car is a manual.
Many thanks in advance for any advice!
Colin

[Pinder]

I think when you put the new head on you should have had it torqued down to 80lbs. its possible that water made it passed the new gasket as it was not on tight enough. also maybe have the head checked for cracks etc.  :(Im not an expert so lets see what the rest have to say on this).

Regards

[merrill]

i had a weeping head gasket issue.

purchased a new head gasket and some copper spray from metric motors.
pulled the head, cleaned the surfaces, sprayed the copper on the surfaces re installed and no issues since.

[Cees Klumper]

The 'mayonnaise everywhere' is especially concerning, given you drove it such short distances since putting the head back on. And of course the white smoke. I would remove the head again and have it tested for cracks, unless upon removal it is clear that the new gasket failed. Best of luck with the repair.

[colin evans]

Thanks guys. For reference if I look at fitting another gasket, what should I torque it down to cold? I used 65 ft lb as per the Haynes manual.
Thanks
Colin

[Pinder]

Colin  check the Haynes manual again for the 280sl not the 230 sl spec.  I took a Quick Look . I think hot engine it’s 80lbs and cold 72lbs. I think you have a 280sl?

Regards

 Pinder

[Pinder]

Here is a photo of the Haynes manual I have from 1977

[Cees Klumper]

The head needs to be torqued down in 3 successive stages and in a specific pattern.

[ja17]

Check the compression in all cylinders before you take the head gasket off again. Remove the plugs and spin the engine with the starter first to expel any water from the cylinders before the compression check. Your compression readings could give you a clue to where your problem is located. You might have a crack somewhere so try to find the cause and location of the failure or you might be wasting your time again. Head bolt torque on a M130 engine should be 80 ft/lbs. in three stages. After first warm-up re-torque the head to 80ft/lbs (warm engine). Re-torque the head again after 500 miles (warm engine). I also use the copper gasket spray. Replacement of the head bolts is not required on the M130 engines that do not have stretch style bolts like later Mercedes engines. Also realize that the blown head gasket allows engine coolant into the combustion chamber which then fills your exhaust system with engine coolant. As the exhaust heats up the coolant in the exhaust, white smoke will return for a considerable amount of time. Eventually the problem lessens and then disappears, as long as everything else is ok. You may need to change the oil twice to purge the water out of your engine or you risk damaging the engine bearings from circulating all the water through your engine.

[colin evans]

Thanks, will do. This is definitely new contamination and the power is well down so something is not right.

[MikeSimon]

Really stupid question (maybe): You are aware of the fact that there are two different head gaskets for the M130 2.8L engine?

[colin evans]

Hi Mike, thanks yes I found this out when the SL shop sent me the wrong one. I stupidly didn’t notice until I started refilling the cooling system and water poured out of the plug holes. Head straight back off and waited for correct gasket to be sent out!

[colin evans]

Joe, what would you expect compression readings to be?  Mine are;
1 105
2 107
3 106
4 98
5 107
6 107
So pretty even except 4 and that’s within the 10% rule, but not sure what the expected figures would be?
Cheers, Colin.

[Cees Klumper]

The tech manual lists values starting at a minimum of 120 and up to 175 psi compression ...

[Benz Dr.]

Those are some low compression readings. I would be surprised if it would barely start and run.

[colin evans]

Ok thanks. Guess I’ll have to strip it down again and get the head crack tested, as I am still none the wiser.

[colin evans]

Hi All
So I pulled the head off again, and whilst nothing immediately jumps out at me I am not sure about the quality of the gasket. This one came from the SL shop (I am in the UK) and was by Elring, I am told that the Mercedes version is no longer made. Does anyone know if there is a better quality option? In same places the metal part of the gasket is literally right on the combustion chamber, and in the close up pic it looks like it has distorted on the edge of the chamber. I also have some questions about valve stem seals but I'll start a new topic for that.
Thanks in advance.
Colin

[MikeSimon]

Mercedes did not make and does not make head gaskets. Elring was/is an original equipment supplier. Elring aftermarket head gaskets are released by Mercedes Benz and should be fine.

[merrill]

when you re torque the head gasket (after 500 miles I think) 

before you start the re torque process.
1. loosen / remove spark plugs
2. remove coolant tank cap.
3. I recommend pulling the lower radiator hose

follow the re torque process exactly

good luck!

[colin evans]

Thanks, just taken the head and inlet manifold to the machine shop for pressure testing. Fingers crossed.
Can anyone tell me the torque setting for the smaller head bolts at the front (2 external and 2 in chain aperture)?
Thanks

[merrill]

hi
if you search the forums you will find the answer.

when i replaced the head gasket on my car it just tightened them by hand. 

[Dave H]

Hi Colin , I’m up in Yorkshire and laughing to myself as I’ve currently got the same troubles.
Rebuilt engine running beautifully until a week ago then lots of white smoke , white smoke very dense as I have the Evan’s waterless coolant in and a tiny bit of that  from a leaking head gasket into the cylinder causes thick white smoke is the downside.
Nothing to loose I torqued to 90 lb ft  last week hoping to stem it but to no avail. Replaced the head gasket yesterday and after work tonight just spent an hour fitting the awkward exhaust manifolds, I hate this part ..Hopefully a few hours each night after work and I’ll know if it’s worked or I’ll be looking for another cylinder head. The intention was to have the head skimmed again as around the water ports still show some signs of corrosion but on measuring it is allready at 93mm so unable to do so.The leak actually wasn’t bad, I was loosing next to no coolant and no overheating, just lots of dense white exhaust caused by what I believe to be the waterless coolant. Like you I had an Elring head gasket and replaced it with another Elring, hardly any evidence that it was leaking on inspection?
The head could be cracked like yours but I’ll soon know later this week if the dense white smoke has stopped or I’ll of wasted a few days for nothing. Best of luck , I’ll be following your progress with interest mate .
Regards .
Dave .

[ja17]

Colin, check your compression gauge, they can give you a false reading when they ingest carbon from the engine.

[colin evans]

Joe and Dave, thanks.
Dave, did you mean 83mm? I think the min is 84mm, mine is nearer 85mm. Sounds like we have a similar issue. Just had a call from the machine shop, the head pressure tested fine so good news. I had the inlet manifold tested too and that is also fine. I have filled the block and levelled the car as best I could and after 10 days lost only a couple of mm of coolant, which may well be evaporation. I cleaned the bores and left them dry for a couple of hours to see if any rust marks appeared, but nothing. Checked the block face and it is straight. So all still a bit of a mystery, although bearing in mind this all started with a brief hydro lock I am still nervous. Hopefully it was something simple like some debris in the bolt holes (I did blow them out) or the torque wrench needing re-calibrating (I'll check that). I can't put it back until together until I track down a new gasket as SL shop are now out of stock until end of June, the one they sent me yesterday was bent in half.
Joe, to save me searching can you remember the torque setting for the four smaller front head bolts?
Cheers, Colin.

[Dave H]

Hi Colin
Hopefully we both just have failed head gaskets, i had hoped my old head gasket would give some indication of this but nothing stood out ?. Only the dense white exhaust for me , no mayonnaise or drop in coolant either, a racing colleague pointed out the dense white exhaust was due to the Evans waterless coolant getting into the cylinder as it smokes like hell he said.
I only ran it a few miles home when it started so should be no lasting damage. 
In the winter i will source a new cylinder head as even after skimming last time the water ports still show some corrosion around them and this worry's me. Given more time i would of had the head pressure tested but i have a couple of shows to attend with the car in the next few weeks so needed a quick turnaround, had it been winter i would of investigated further.
The 83mm is genuine so possibly the higher compression this might cause and the fact that i omitted to do a 500m re-torque of the head bolts since rebuild may be factors in my case ? I will know on Saturday when i fire her back up.