petrol in coolant fluid

W113 Roadster 1963-71 230SL, 250SL, 280SL
W121 Roadster 1955-1963 190SL
W198 Coupe 'Gullwing' and Roadster models
Post Reply
hands_aus
Finnie
Posts: 294
Joined: Wed 22 Feb, 2006 9:46 pm
Model you own: w113
Location: Brisbane

petrol in coolant fluid

Post by hands_aus » Sat 07 Feb, 2009 10:12 pm

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?
Bob Smith
Brisbane

1967 'early' 250SL, auto, PS

CraigB
OZBENZ Admin
Posts: 5004
Joined: Thu 23 Jun, 2005 1:18 pm
Model you own: I own multiple different models
Location: Hawthorndene (Adelaide)

Re: petrol in coolant fluid

Post by CraigB » Sun 08 Feb, 2009 12:16 am

Wow Bob. It is getting late so just passing on some gut instinct that the whole petrol can thing sounds a bit odd. Are you having any loss of fluid, overheating etc.? Just thinking how fuel might make it into the cooling system and wondered about head gasket. If it really is just the residue of petrol from a can, I can't imagine it will have any long term affect on seals but other opinions will be interesting.

With your crank seal, do you know if they did anything with the pulley? Over time they can get a groove in them which if shallow might be able to be machined, but another solution is something called a 'speedisleeve' or something like that which is a very thin sleeve (stainless I think) that can be pressed on to that contact surface on the pulley and probably last longer than the original.

Craig
Craig Baulderstone
Lurch
280s's
280SE3.5
280SL
350SL
500SEC's
560SEL's

User avatar
Hendrik
Mercedes Demigod
Posts: 5497
Joined: Thu 28 Jul, 2005 10:33 am
Model you own: w124
Location: Hawthorndene SA

Re: petrol in coolant fluid

Post by Hendrik » Sun 08 Feb, 2009 11:00 am

Sounds like you need to change workshops.
Given the amount of fuel I'd say there may have been fuel left in the container used for storing the coolant :roll: sure people make mistakes but that is just so dumb.
Yet another example of why I like to do as much spannerising as possible, sure I make mistakes but not that dumb.....yet.
I have a bucket I use just for coolant, whilst it is in there I put a plastic bag over the top and use a 1.25L plastic soft drink bottle with a pair of stockings in it to filter the coolant back into the engine.
I also have dedicated sump oil bucket and use the tops of soft drink bottles as funnels. I make sure to wipe them clean prior to using them to pour fresh oil into the engine. The size of the bottle funnels make it easy to give em a wipe over. Also I use the funnels to tip waste oil back into oil containers to store the stuff until such time as I make a run to the recycling station to get rid of all the old fluids. It is also handy to use the funnel to drain all the oil out of the bucket by positioning it in such a way that the spout of the bucket sits inside the funnel and after a few hours just about all the oil is out of the bucket.

hands_aus
Finnie
Posts: 294
Joined: Wed 22 Feb, 2006 9:46 pm
Model you own: w113
Location: Brisbane

Re: petrol in coolant fluid

Post by hands_aus » Sun 08 Feb, 2009 9:45 pm

Hey CraigB,
The fuel and water should not mix given the separated fuel lines and water channels.
Also this situation is new and not existing with no previous water leaks or fuel in the coolant.
The spacer ring I had replaced sits on the crankshaft and the shaft/spacer combo spins on the seal.
See #14 on the attached pic.
I am not sure what you mean about the 'groove in the pulley'. Maybe the pic will help you explain it to me.
VibrationDamper250SL.jpg
Hey Hendrik,
I have been doing the general maintenance, grease and oil change, tuning etc on my Pagoda with no cross contamination of fluids and I am a backyard mechanic.
This job required the radiator to be removed from below so a workshop situation was needed, which I don't have, so regretably I took it to professionals.

My understanding is that water hoses/seals and fuel hoses/seals are made of different materials and water hoses/seals are not supposed to come into contact with petroleum products.

Thanks for your replies
You do not have the required permissions to view the files attached to this post.
Bob Smith
Brisbane

1967 'early' 250SL, auto, PS

User avatar
Hendrik
Mercedes Demigod
Posts: 5497
Joined: Thu 28 Jul, 2005 10:33 am
Model you own: w124
Location: Hawthorndene SA

Re: petrol in coolant fluid

Post by Hendrik » Mon 09 Feb, 2009 12:53 am

Professionals? Pffft.........professional at taking money out of your wallet maybe.
No, ideally petrol should not enter the coolant circuit but I doubt it would have done any damage if it was in there for a short time and wasn't that much.
If the shop was any good they'd tell you to bring the car back in 500ks time for another flush. If there is still petrol present in the coolant, then I would suggest that the amount of fuel was substantial and a replacement of all the rubber was necessary.

hands_aus
Finnie
Posts: 294
Joined: Wed 22 Feb, 2006 9:46 pm
Model you own: w113
Location: Brisbane

Re: petrol in coolant fluid

Post by hands_aus » Fri 20 Feb, 2009 8:14 pm

Thanks for your responses.

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".

The Pagoda website has a TOUR for the adjustment of the VALVES here
http://www.sl113.org/forums/index.php?topic=10218.0

Next time I might have a go at adjusting them myself.

Again thanks for your responses.
Bob Smith
Brisbane

1967 'early' 250SL, auto, PS

CraigB
OZBENZ Admin
Posts: 5004
Joined: Thu 23 Jun, 2005 1:18 pm
Model you own: I own multiple different models
Location: Hawthorndene (Adelaide)

Re: petrol in coolant fluid

Post by CraigB » Sat 21 Feb, 2009 8:52 am

I'm glad that worked out OK Bob. My initial comments were based on not believing someone could be stupid enough to do that - I mean it is not like petrol is odourless when they picked up that container.

I don't know the clearances off the top of my head but if that is correct it should be right. The last thing you want is clearances that are too tight. I might be quieter but if too tight the valve doesn't close properly and you end up burning valves.

I guess they were honest about their motivation to fix it but wouldn't it be nice to have a mechanic that just fixed it because it was the right thing to do, not just because they could see they might lose business beyond you! I guess that's why I should never go into business, I would probably go broke doing the right thing!
Craig Baulderstone
Lurch
280s's
280SE3.5
280SL
350SL
500SEC's
560SEL's

User avatar
John Green
OZBENZ Admin
Posts: 6610
Joined: Mon 20 Jun, 2005 3:49 am
Model you own: w112
Region: Australian Capital Territory
Location: Canberra-center of the known universe
Contact:

Re: petrol in coolant fluid

Post by John Green » Sat 21 Feb, 2009 9:19 am

Early engines being more rattly after a head job or valve adjustment is not that uncommon. The cause is that the ball pivots (the bit you turn to adjust the clearance) is no longer round but slighty oval. Now all is well and it has worn into he rocker arm, but when you turn it the two worn surfaces no longer mesh correctly.

We had one a few months back that sounded like a diesel after doing the clearances, but it was a strange one with one very loud rattle, isolated it to which rocker it was by rubbing the engine with our "see through" rocker cover and replaced the offending ball pivot and rocker arm, ran perfect after that.

One of you clever guys that posts up the pictures of the parts books put the rocker arm picture up and you will see what I mean.
Inaugural OZBENZ national meet this September, all welcome to attend. https://ozbenz.net/viewtopic.php?f=46&t=25165

M.B Spares & Service 14-16 Lyell St, Fyshwick ACT. Ph 02 6239 1099

http://mbspares.com.au - Supporting Australia's Mercedes-Benz Enthusiasts.

CraigB
OZBENZ Admin
Posts: 5004
Joined: Thu 23 Jun, 2005 1:18 pm
Model you own: I own multiple different models
Location: Hawthorndene (Adelaide)

Re: petrol in coolant fluid

Post by CraigB » Sat 21 Feb, 2009 9:41 am

Thanks John, that makes a lot of sense. I certainly have spares with noticeable wear but hadn't thought about the effect of rotating that in adjustment. I am a bit desensitised to rocker noise though and more worried if it sounds a bit silent!
Craig Baulderstone
Lurch
280s's
280SE3.5
280SL
350SL
500SEC's
560SEL's

hands_aus
Finnie
Posts: 294
Joined: Wed 22 Feb, 2006 9:46 pm
Model you own: w113
Location: Brisbane

Re: petrol in coolant fluid

Post by hands_aus » Sun 22 Feb, 2009 9:50 pm

Hey John,
Thanks for that info.
Reading your response I gather that it is ok to replace ONLY the worn adjuster pivots and rocker arms and not necessary to replace them all.
I am going to have them check the valves again in about a months time... after the next club run to the Sunshine Coast.
So if there is a problem I may ask them to adjust them to .003 and .007" and if necessary replace the worn adjusters and rocker arms that need it.
again thanks
Bob Smith
Brisbane

1967 'early' 250SL, auto, PS

User avatar
Mercmad
Mercedes Demigod
Posts: 8055
Joined: Sun 11 Sep, 2005 8:01 pm
Model you own: w109
Location: Brissy
Contact:

Re: petrol in coolant fluid

Post by Mercmad » Mon 12 Oct, 2009 12:09 pm

I think i know about this story... Actually petrol in the water is no big deal,it's volatile and will evaporate at engine running temp with zero harm to the hoses etc. I would have simply ran the engine at running temp with the cap off. Simple?
I would be more concerned with water in the petrol,then you would have cause for concern.
or a leaking water thermo on the MFI pump leaking coolant into the pump ( yes i have seen this often and a 6.3 has an MFI pump which costs $48,000 !).
TAppets shouldn't be audible from the drivers seat. It's annoying and it will further exacerbate wear problems . The best way to sort them out is to listen the hot engine as it idles then mark on the cam cover where the noisiest ones are. then with the engine dead cold check the clearance. give the tappet a whack against the pivot with a small hammer and check it again. you will see a difference of a few thou ,split the difference and reset it ,give it another whack to make sure and it should be OK for the next 12 months.

hands_aus
Finnie
Posts: 294
Joined: Wed 22 Feb, 2006 9:46 pm
Model you own: w113
Location: Brisbane

Re: petrol in coolant fluid

Post by hands_aus » Thu 15 Oct, 2009 2:17 pm

Follow up I thought you might be interested.

In March they asked me to take the car back in a couple of months so they could re-check the valves.

So in May I took it back thinking that as they were going to take the valve cover off again it would be a good time to have the timing chain and adjuster replaced.

They gave the job to the same mechanic who worked on the car previously.

During the wait of 4 weeks for the genuine adjuster ($480.00) to arrive from Singapore, they had the car with the valve cover off in their workshop.

When the mechanic was replacing the timing chain he dropped the chain connecting clip into the engine.
He removed the oil pan (a new seal $65.00 was fitted in March) to retrieve it.

The distributor (PERTRONIX FITTED) was removed to help align the timing marks.
When the distributor was refitted the PERTRONIX module was incorrectly wired up which 'blew' it. The car wouldn’t start.

As I was expecting to have the car back that day, I called them asking about it and they told me it wasn’t running because the Pertronix module wasn’t working.
The old (almost new) points that were kept in the front subframe recess were installed.

They got the car going but very badly...way too rich.

The mechanic told me they asked a ‘Pagoda Expert’ from their other workshop to help set it up but he couldn’t make any difference.

Checking the car after bringing it home, I found that the ‘EXPERT’ adjusted the Venturi valve to be open at idle, shortened my linkage rods and had 'leaned' the fuel screw on the injection pump to the point where it had lost the ‘click’ feel.

The dwell was set incorrectly at 32 degrees (38-41degrees) and the timing was set at 8 BTDC with vacuum when it should be 2-4 degrees ATDC with vacuum (hot idle).

When I corrected these settings the engine was running too lean allowing me to richen the injection pump fuel screw to the point where the ‘click’ returned.

As part of their fiddling they disconnected the non-standard start-up ballast resistor by-pass relay that I had installed. Now re-installed.

I adjusted the air fuel mixture using the injection pump 'link-rod off' test.

I took the car for a drive and could here a rattling noise under the valve cover so I took it back to the workshop supervisor and asked him to listen.

He immediately asked me to bring the car back and THIS TIME he would check the valve adjustment.
I told him I want it done with the engine cold with .003” inlet and .007” exhaust settings.
Previously he told me that he prefers to do the adjustments on a hot engine.

The Company offered to pay for a new PERTRONIX unit plus the plastic tube from the valve cover to the inlet manifold because the mechanic broke the original one by bending it back instead of disconnecting it.

I set up the timing etc again and the car seems to be going great.

This whole process took 10-11 weeks when it should have taken 1-2 days at most.
Bob Smith
Brisbane

1967 'early' 250SL, auto, PS

CraigB
OZBENZ Admin
Posts: 5004
Joined: Thu 23 Jun, 2005 1:18 pm
Model you own: I own multiple different models
Location: Hawthorndene (Adelaide)

Re: petrol in coolant fluid

Post by CraigB » Fri 16 Oct, 2009 6:06 pm

So have you found a new mechanic Bob! Is it the same one that didn't do up your driveshaft bolts?
Craig Baulderstone
Lurch
280s's
280SE3.5
280SL
350SL
500SEC's
560SEL's

hands_aus
Finnie
Posts: 294
Joined: Wed 22 Feb, 2006 9:46 pm
Model you own: w113
Location: Brisbane

Re: petrol in coolant fluid

Post by hands_aus » Sun 18 Oct, 2009 4:46 pm

Hey Craig

It was the same company but their new workshop just on the inner north of the CBD.

I am still looking for a new workshop because as you know there is always the next project.

cheers
Bob Smith
Brisbane

1967 'early' 250SL, auto, PS

Post Reply

Return to “W113 and W121 Roadsters & W198 300SL”