SEC problems

Oshbosh

Hi,

okay, its only 17 but the SEC series is 26 years old so i think it still qualifies as a classic (for this forum anyway i hope! )
Okay, just bought a beautiful 420SEC, 76k FMBSH. Onlu done about 5k in the last 5 years but was MOTd every year, hadn't had a service during that time though until just before i bought it.

Yesterday after being out for a run for about an hour i started hearing a slooshing / churning kind of a noise which seemed to be coming from the area in front of the driver, i could only hear it while stopped at traffic lights,junctions etc.

At this point the temperature guage was at around 40-50 degrees, the oil pressure was at the top of the guage at 3, so i think normal
for both of these.

When i got the car home i sat and listened to it for a few minutes with the driver's door open. Next thing steam starts escaping from the corner of the bonnet by the driver's wing mirror and through the hinge area of the open door, then a liquid started pouring onto the ground from, what appeared to be under the driver's door, the liquid was green and i'm sure it is the anti-freeze.

I let it cool for an hour or so and brought some water to fill the head tank for the radiator. ( i think this is the correct name ).

It filled up but if i waited a few minutes i could always put a little more in, looking through the plastic tank it seemed to be about 3/4 full.

This morning the water level in this tank had dropped to about 1/4 or less.

I'm hoping this is just some piping which may have perished over time due to the car not being used regularly, or possibly a water pump, anyone have any ideas ?

thanks

Osh

Oshbosh

a wee photo !

PaulK_CCI

sounds very much like a knackered waterpump bearing.... the churning noise, and then the water escaping at standstill...

I'm sure our two Merc specialist "Ben's" will be able to answer that one in more detail for you.

MercMad

I hate to tell youi but it sounds like the interior heater matrix has ruptured. Hopefully it could be a hose, but I doubt it, and either way I think this will be a dash out job to rectify, not cheap !

Check under the carpets, right as far down as you can to see if they are damp. Also it is possible that it is one of the electrically controlled valves near the bulkhead in the engine bay !

Sorry cant help you any further, but I recommend you dont drive it, or if you have too bring lots of water and put the heater / A/C settings to cold !

Oshbosh

thanks guys, thinking about it i think the churning noise may have been a boiling sound,

8~)

Congrats Oshbosh - apart from this overheating incident I'm sure it will be a great car.

Couple of comments: if the temp gauge was at 50ish degrees after an hour's driving then the engine is running cool - should be at 80ish. That gurgling could have been overheating in the matrix or maybe an airlock... do you get hot air from the vents when the engine is up to temperature?

Did you measure how much water/coolant you put in. Not sure of the capacity of your SEC but it'll surely be more than the standardish 4 litres.

As said by MercMad, check for dampness around inside the car under the dash, etc.

With any luck there's a leaking pipe somewhere and an airlock... if not it could be more serious, as indicated by other posts.

Stevo11

I'd vote for a thermostat change and a coolant change + bleed.

If it still happens I'd move on and check the previously mentioned valves near the bulkhead in the engine bay.

Much much easier than a dash out ;-)

Steve

Oshbosh

thanks guys,

i put in probably 1.5 litres of water, every time it came up to the lip it would subside after a few minutes, and i could put in a little more. you say it might take as much as 4 litres ? Is this the total of radiator plus the head tank ? There's no way the head tank can take 4 litres. If this is the case then perhaps i didn't have enough water/anti-freeze in the car to begin with ?

It just had a service though so i'm guessing those levels were correct.

lot to think about, i need a professional to have a look at it i think,

never thought i'd be praying for an airlock or a busted hose but here goes...!

cheers

Osh

Oshbosh

Anyone know any Merc specialists in the central Dublin area.

I've contacted Benjamin Lichtenberg but he can't look it for 3 weeks, and i'd rather not wait,

cheers

Osh

3ps

phibsboro John Keaney?

sorry for your woes, it's a lovely looking car.

Oshbosh

Found a guy in Harold's Cross called Sean Murphy, Greenmount Motors. Anyone used him ? He charges 80euro per hour + VAT, is that what the rates are like these days ? Sounded like a decent guy though and not too far away although i need to check where / how bad the leak is first before venturing out

corktina

shoot me down in flames if u like but i would guess the header tank will have a full mark somewhat lower than the filler lip. It is probable (Guess) that the level falls because there is an overflow to take away the excess. (proper name for header would be expansion tank....needs room for expansion Id say...

8~)

If water/coolant has leaked out, 1.5 litres will barely wet the pipes. Capacity of the cooling system is likely to be around 6 litres on that car. You mention the car had a service - coolant change is not part of a standard service.

In order to fix I'd start with the basic and cheapest options and work up... start off by bleeding and refilling and determine if there is actually a leak.

...finish up by changing head gasket... though thankfully no mention of plumes of white smoke or oil in the water.

Dades

Oshbosh wrote:

Found a guy in Harold's Cross called Sean Murphy, Greenmount Motors. Anyone used him ?

He had my SL for a day and solved a vibration issue I had. Wasn't a huge job I gather, but he sorted it out out great (€200 if I recall). They were stripping an Aston DBS in the workshop too!

MercMad

Sean at Greenmount is highly recommended by the MB Club here. Still any mechanic can pressure test a car like that so I would be inclined to fill it with water and drive to your nearest back stret garage having placed a quick phone call previously !

mike65

Is there any sign of a greasy film on the inside of the windscreen? If the matrix is borked thats a common sign not to mention a slightly sweet smell when the fans are running.

Mike.

Oshbosh

put some more water in it on Friday and the level hasn't dropped this time.
Only thing is now the car won't start ! All the lights seem to come on as normal, but when i turn the key there is a single click and then totally dead.

Looks like i'll have to get it trailered over there, has anyone here used a service like that ?

thanks

andreas_220D

Oshbosh wrote:

All the lights seem to come on as normal, but when i turn the key there is a single click and then totally dead.

sounds like your battery needs to be recharged

8~)

Second the flat battery theory.
Good the level hasn't dropped. However you need to check it with the engine running also in order for the cooling system to be pressurised.

Oshbosh

okay, is there any chance the flat battery is related to the coolant system problem in some way ? Just seems strange it would go flat all of a sudden.

I did put water in it while the engine was running on Friday morning but could only put a little bit in.

8~)

No logical way the flat battery could be related to the coolant issue.

Oshbosh

took it down to see Sean Murphy and its not looking good, he says it needs the cylinder head gasket replaced. We let it run for 20 mins to heat up and he placed a funnel over the radiator cap and poured in some water every now and again. He then revved it slightly and you could see the water bubbling, more each time he revved it up. Said the seal has a leak and air is being pulled through into the engine, which then ends up in the coolant sytems, i think that's what he said does this sound right ?

Anyone fancy a guess at how much this might cost to fix ?

Mr Murphy didn't want to it himself. I'm going to speak to the Dealer as well and see if he will help, he said he gave 3 months for anything big so i think this counts.

Sean Murphy was a really nice guy though, didn't charge me for taking a look at it,

8~)

...that's a pity. I did say earlier worst case it was head gasket but really didn't think it would be because you didn't mention any other symptoms of gasket failure.

Regarding cost to change it... I have no idea. It requires a lot of stripping just to get to the gasket. Much of the charge will be labour.

MercMad

You have somne kind of warranty with a dealer...............thats great, definitely use it !!

Strange that Sean wouldn't take it on, he must be out the door !

Oshbosh

i think he said the job was too big for them, a lot of heavy lifting or something.
I asked if there was any possibility it was something else but he said no, definitely the head gaskets. Is the test he did on my car scientific enough do you think ?

We'll have to see what the dealer says, as he's in England but fingers crossed. thanks everyone, what a feckin pain in the ass, i guess this job will probably need to be done at some stage but pity it has to be now.

8~)

Better now than in 4 months time. With any luck the dealer will be somewhat decent. Is it an established classic dealer?

The test Sean did is probably scientific enough - there shouldn't be air in the coolant and the bubbles indicate air getting in.

Oshbosh

the dealer was a decent guy, didn't deal in classics per say but interesting cars, he had another Merc coupe there and quite a few volvos, i'd like to get some kind of idea of how much this costs before approaching him, wish me luck, thanks everyone,

beanderb4

Oshbosh,

I blew the head gasket on my 280 SEC last year. A well know classic merc specialist was looking for Euro 1,300 plus to do it. That should give you a feel for what is involved cash wise!! PM me and I'll give you the name of a guy that may do it cheaper for you if your dealer does not cover it - however your dealer really should do it.

Cheers.

andy.s

Anyone selling SEC parts ?

Eric318

Damn I love those SECs! More than once have I been about to part with good cash for one of them!! But I have always been kept away by the complexity of the mechanics (well, first time round it turned out that the chassis number had been tempered with... A magic ray of sunlight alerted me to the fact...).

Oh man that head-gasket story is sad. Like others say, you should try to get your money back and look for another car. May be you can strike a deal with the seller for a price rebate but make sure you have the work done by someone of will be loyal to you not to him as his incentive will be to do a quick/cheap job. You never know where a leaky CHG can lead to (skimming the head, cracks, etc. and while the head is off, why not get into a full engine rebuild, none of which you wanted to get into in the first place...)

I found myself in a similar situation when I bought my first XJC. The situation escalated to the point of involving lawyers. The mechanic kept the car for weeks supposedly to fix it and then... went bankrupt. I had to bribe one of his "associates" to get my car out of the sealed workshop on a Sunday morning without the liquidators knowing... There is nothing like doing business with straight people. And this is a hobby after all, it does not have to be excruciatingly painful all the time...

Good luck though.

Oshbosh

Hi,

so, good news about the SEC ! I took to a guy recommended to me by my Uncle, who is the trade, and he had it fixed in a day !

The problem was a blocked radiator plus a faulty temp sensor and also a hose at the back of the engine was loose. New rad, sensor and tightening of the clip on the hose has solved the problem.

Thank God ! I was bricking it in case it was a gasket job and had very little luck finding someone who wanted to take on such a job.

He said the temp guage was now reading a little low, 60 instead of 80, and that i would need a new transmitter for this, anyone know what this is ?

After replacing the rad and sensor he let it run for a few hours and said it was running perfectly with no overheating. I'm a little worried about the temp guage reading low and would like to get this transmitter thing fixed, if anyone can clarify what this is please let me know.

I drove it up and down to Donegal over the weekend and it drive just great, thoroughly enjoyable, a real magic carpet ride !

Thanks very much for all your help everyone,

Osh

ps here's the guy's details, a really nice guy to deal with, seems to specialise in Mercs, Jags and BMWs

Peter Sheridan
1A Maxwell Road
Rathgar
01 4978004

tc20

Good news Oshbosh!

Glad you got the car sorted and back on the road. I love those SECs and hope to get round to having one someday. Did you put the contact details in the sticky for specialists?

hi5

For transmitter ,he could mean 'sender'?

Oshbosh

will put his details in the sticky now.

What is the sender ? Sounds like something which 'sends', the data from the temp sensor to the guage, is that right ?

I was thinking this might be it but was then wondering why the temp guage was reading anything at all if this part needs to be replaced ?

MercMad

Glad you got sorted !

To be honest a temp sender is the same thing as a temp sensor, just different terminology. The SEC has several, maybe your guy could be a bit more specific !

There are 3 units are located around the thermostat housing, where the top rad hose goes, and all are marked "Water temperature gauge" on the parts info. Obviously you have one for the gauge, then another for the ECU and I expect another is a changover switch !