PETROL IN COOLANT FLUID

[hands_aus]

Yesterday (Friday) I had the Front Crankshaft Seal replaced AGAIN (last time May 2008). This time a different mechanic from the last time (same company) replaced the spacer ring plus the oil pan gasket which required the radiator to be removed.

I could smell PETROL/GAS when I removed the radiator overflow tank Cap as part of my usual checks to make sure the fluid levels (engine oil, coolant, battery, brake fluid) were correct.

I spoke to the mechanic who did the job and he admitted that the coolant (less than 12 months old) was stored in a container that had previously been used to store fuel/gas and that is where the smell was coming from.

He then proceeded to tell me that there would be NO problems now or in the future with seals/hoses.
I suggested that I might flush the system and add new coolant. He said that it would do no harm to do so.

About 30 minutes later, because I was unhappy with his explanation, I called back and spoke to the supervising mechanic and told him of the situation.

He nearly had a fit. He asked me to return the car and he personally flushed the system as all the staff had left for the weekend.

The heater valve was opened and the engine was started during the 2nd flush.
I watched and after flushing there was no PETROL in the water coming out of the car.

He then filled the system with new coolant.

After driving the car home (about 5Km) and letting it cool over night I checked the coolant fluid. I can smell petrol also I can see some fuel floating on the surface.
On Monday I have to take the car back for a complete flush out and new coolant again.

HERE ARE MY QUESTIONs

Will the 2 flushes be enough to clean the petrol/gas out of the system?

What seals are likely to be damaged short term or permanently?

Is there anything else I should consider?

[bpossel]

Hi Bob,

That sounds terrible!

Lets let the experts answer your questions, but I would say (non expert opinion), if there was a small amount of fuel in the can, mixed in with the radiator fluid, and this was only in the engine for a short period of time, probably no real issue.  It is good that you caught it early.

If it were me, I would drive the car with the heater on and let the fluid flow....  I would then keep taking it back to your repair guys and have them drain and replace the fluid until the smell of fuel is completely gone.  With all of the nooks and crannies (technical term...) in the engine, it could take several flushes to get it all out.  I would also demand MB brand radiator fluid, at their expense.

Good Luck!
Bob 

[merrill]

would it be reasonable to do a coolant system flush and de oil?

citric acid flush and de oiling the system then adding new coolant should do the trick?

[Shvegel]

I don't think that the small amount of fuel left would do any harm to the hoses etc. but I can sense that you still find it annoying. Since gasoline is so volitile I would try simply leaving tha cap off overnight and just letting it evaporate.  Since the top of the radiator is the high point in the system and gasoline is lighter than water it should collect there.

It might take a time or two to get it all but you will sleep better at night.

The mechanic who flushed the system is the one to keep. Speaking as a former line mechanic, BMW Instructor and current Chief Engineer on Large private yachts anyone who will take the time at the end of the day on a Friday to fix someone else's mistake is a rare individual indeed.  Ask that he alone work on your car and if he does a good job tip him.  It isn't so much that he needs a little extra money(beer, coffee and baked goods are also appreciated) but the cachet in the shop of being able to tell the other mechanics he got a tip for doing a good job will make him remember you.

Mistakes and misdeeds happen. It is how people recover that really speaks to a man's character.

[scoot]

"the coolant was being stored in a container that previously contained gas" -- Is he saying that the container still had some gas in it?  I'm wondering if there is the possibility of gas being introduced into the cooling system in some other way.  (Is there another way - like a blown head gasket or something?  I would think that would mess up the oil more than anything else...)   Anyway, it sounds really strange that the mechanic would mix coolant and gasoline.  Something fishy about this story.   Maybe it is just that the mechanic was an idiot, or maybe it is something else.

[glenn]

Do 'petrol' and glycol mix?

[66andBlue]

Glenn,
that question as stated is difficult to answer.
If you mean 100% pure glycol then the two may mix quite a bit. Just like dry ethanol mixes with gasoline (E15 or E85).
But when you add water (to make antifreeze, say a 50% solution) the situation changes drastically, there is very little mixing of the water/glycol mixture with gasoline. That is why pure glycol is used, for example, to dry liquified gas, it "sucks out" the water.  My guesstimate is that less than 0.01% gasoline is dissolved in a 50% glycol/water mixture.

[Benz Dr.]

There's no way gas can get into coolant unless you put it there. I've seen ATF get into coolant if the oil cooler in the rad had a leak and I had a engine recently that put a lot of oil into the coolant because there was a small hole in the block. That was on a 300SE which has an aluminium block. The 250SL could also leak oil into the coolant if the oil cooler started to leak.

Oil, ATF and gas won't mix with coolant. It can go into emulsion while the engine is running but will separate out once the mixture cools. It all depends on how much oil you have in there.

I always keep my fuel in approved containers. Used antifreeze is a bit different and new stuff stays in the container until I use it. Once in a while a bit of oil will get into antifreeze while it's being drained if oil is dripping somewhere but I use new stuff unless it was new to begin with. If it's really contaminated then I'd get fresh coolant.

There IS something fishy about this story. It has the same smell about it as all the posts about inept vendors and idiot mechanics that I see here on a regular basis. The poster has a genuine question and all but we need to separate that from our personal problems with those we do business with. 

[scoot]

There IS something fishy about this story. It has the same smell about it as all the posts about inept vendors and idiot mechanics that I see here on a regular basis. The poster has a genuine question and all but we need to separate that from our personal problems with those we do business with. 

It wouldn't be THE FORUM without the voice of reason that Dan brings to us, centering us back on the point at hand!!!!   Thanks Dan!!!                           

[waltklatt]

Hello Bob,
Wow, lucky you got it in time and the master mechanic knows the situation.
Petrol in the coolant will cause problems as petrol expands at a fast rate and can lead to boil over if youre not careful can lead to a purge of the vital coolant. 
Keep your eye on the temp guage and level in the expansion tank.  Also keep a few coolant containers full in the trunk in case you notice a spike in the temp or loss. 
The 'idiot' should be tarred and feathered for such a dumb move.  Never mix fluids for the car in different containers.
That's why we have containers that are labeled seperately for each type of fluid.
Check the head gasket and seams for the coolant periodically.  Perhaps disconnect the hoses and flush with warm water, using prodigious amounts of water.
Walter
1967 220SL-diesel

[Benz Dr.]

This is more supposition than reality. I might be able to smell perfume but it doesn't mean I'm wearing it.

If the rad has been flushed out how much gas do you really expect to be left in there? The smell doesn't mean a skunk is in your house or in your car.
 Never have I seen such an over wrought reaction to a sorted out screw up. It's not like the car is going to blow up like in the movies or something, although the thought obviously unglued a few people.

The original mechanic admitted that the used coolant was stored in an empty gas can and that it wouldn't hurt the engine. He also went on to say that it wouldn't hurt to change the coolant if the owner wanted to. The owner of the shop, when contacted by the owner of the car, made a bigger deal out of it than the situation called for because he wanted to save face. There was nothing dishonest about anything that the shop did. Some of the over reaction was to calm the customers fears which I can fully understand. However, in this case I don't think it worked all that well and nothing I've seen posted here has helped to further that cause.

So, I'll give it to you straight up.
The head gasket won't start to leak. The hoses probably won't ever swell up. The engine won't start to overheat or blow up, the sky won't fall...... there is a tomorrow.
 

[hands_aus]

Guys,
Thanks for all your responses.

Dan, thanks for your assessment of the situation.

"The head gasket won't start to leak. The hoses probably won't ever swell up. The engine won't start to overheat or blow up"

The Leading mechanic knew I was a member of the local MB Club and he said that as they were trying to get more club member business, they must do the right thing and correct the problem or I would discuss the situation with everyone I knew.
He was right.

I spoke to the Service Manager and suggested they use this situation as an opportunity to assess their workshop procedures and as the mechanic was new to the company that they tell him of their practices and company standards.

I took the car back on the Monday and left it with them.
After flushing the cooling system 2 more times the Service Manager decided there was no more fuel in the coolant.

This company went out of their way to correct this problem.
I have no problem with them on this matter.

As part of the crankshaft seal job they found the valve cover seal was a bit old and suggested that I have it replaced.

I thought about it and as I had previously purchased the valve cover seal and bolt copper washers, and as they already had the car there, I suggested that they adjust my valves at the same time.

The mechanic adjusted them to .004" and .008" inlet and outlet respectively. He said that was the MB spec and the engines run better at those settings.

When I picked up the car after the work, the Leading Mechanic and I had a smell and a listen before I left.
The coolant was clear of fuel (big nose here) but the engine was clanking away.

I suggested that the valve cover bolts were too tight and after having them loosened and tightened the engine seems to be going well.

MY opinion is that the engine is noisier overall than it was before.
The Leading mechanic suggested that after running it around for a month I take it back and have them check the valve clearances again.

It is a bit like "they will ride up with wear".

Again thanks for your responses.

[Benz Dr.]

This sounds like a place that is making efforts to make things right and is customer oriented. You can't go too far wrong doing that.

We always set the valves on 113's to .003'' and .007''
 .00 4 and .008 is OK for really cold weather as it aids a bit in starting but most drivers don't use their car in the winter.  The noise you hear won't go away and may get worse in time.
Thing is, you can hear a loose rocker but you can't hear a tight one. That's why it's a good idea to check them and particularly on an unknown engine.

When a car comes in I just assume it hasn't received any real maintenance and usually do everything unless I can see that it's been serviced. This sets a base line from which to start and I'd recommend that to anyone.

[ja17]

Yes I agree with Dan and Shvegel,
The small amount of fuel and the short time involved will most likely cause no problems.   If left  in larger quantities over a much longer time, the rubber coolant hoses could deteriorate and the water pump seal may suffer.