Unlead?

How can we define a car that have been converted to run on unlead? I mean apart from the sticker.

Many thanks in advance.

Reply to
mini86
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Have a look where the head joins the block, for signs of a new gasket or new sealant. If it doesn't look as though the head has been off recently, then it probably hasn't been converted.

Unfortunately, if the head has been off, it doesn't prove that the conversion work was done.

Jim

Reply to
Jim Warren

Jim Warren ( snipped-for-privacy@OMITblueyonder.co.uk) gurgled happily, sounding much like they were saying :

Not does it prove that any was needed in the first place.

Reply to
Adrian

I was looking into this myself

I'm going to be looking at a few Mk1 Escorts this weekend, do they need to be converted, one owner says he runs his 1970 model on unleaded with no problems but has had no convention work done

Reply to
BORG

The message from "mini86" contains these words:

Define? What exactly do you mean?

Establish whether it has been converted or invent a snappy title for the class of converted cars?

If the second 'Unplumbed'?

Reply to
Roger

I've no experience with Escorts, but there are some engines which theoreticaly need to have hardened exhaust valve seats fitted, yet in practice are quite tolerant of unleaded fuel. Previous use of leaded petrol causes a "lead memory" effect, where deposits of lead compounds have formed a hard coating on the valve and seat. In the case of many Triumphs, around 20,000 miles of using leaded petrol leaves enough lead memory to last the life of the engine (typically 100,000 before substantial rebuild). I know other cars are far less tolerant, the BMC A-series is reputedly quite prone to problems, though I've no personal experience. As for the Escort I really don't know, but I would have thought that a relevant owners club would have discussed this previously, is there a specific messageboard? Cheers, Bill.

Reply to
Bill Davies

Most cast iron head engines will give problems sooner or later. Of course if you drive gently it will be later...

Reply to
Dave Plowman (News)

BORG realised it was Sat, 03 Dec 2005 09:19:22 +0000 and decided it was time to write:

No car 'needs' to be converted. Most cars with engines designed for leaded will happily run for tens of thousands of miles on unleaded before there's any sign of valve seat recession. Don't be misled by the FUD spread by the press and other people.

Did he say how many miles he has done on unleaded? Do you know his driving style?

Reply to
Yippee

NO but he seems to be a fan of Mk1s and said he didn't thrash it as it was an old car, it's also an automatic

Reply to
BORG

It's obviously high temperatures that eventually cause the valve or seat to fail - hence the greater problems with the siamese exhaust ports on BMC engines. So driving style will have quite an influence.

Reply to
Dave Plowman (News)

Ask to see the receipt for the conversion!

Reply to
Peter Hill

But you might need to look at the timng to avoid pre-ignition - e.g. my old

1300 Cavalier was easily "converted" to run on unleaded by adjusting the timing.

Reply to
R. Murphy

BORG realised it was Sat, 03 Dec 2005 11:19:21 +0000 and decided it was time to write:

In that case I wouldn't worry about valve seat recession if I were you. Careful owner and auto box equals long engine life.

Just run it on unleaded until you've run out of adjustment on the valves. By that time, the engine will probably need a complete rebuild anyway.

Reply to
Yippee

Dave Plowman (News) ( snipped-for-privacy@davenoise.co.uk) gurgled happily, sounding much like they were saying :

Unless they had hardened inserts from new.

Reply to
Adrian

Think this is pretty rare until unleaded arrived.

Reply to
Dave Plowman (News)

Thanks for all replys. Sorry about misleading, as I am a foreigner.

The car is actually a 84 Merc 2.8 straight six. Does it got a Aluminium head or a Cast iron one? Any idea please?

Reply to
mini86

Dave Plowman (News) ( snipped-for-privacy@davenoise.co.uk) gurgled happily, sounding much like they were saying :

Not unless the head also went into cars heading stateside.

Reply to
Adrian

Think all '84 German cars are ok on unleaded.

Reply to
Dave Plowman (News)

Would depend on when. Things like MGBs didn't have inserts when exported to the US.

Reply to
Dave Plowman (News)

Head is Al.

I had a '83 280TE which said it needed 4star(98RON) leaded, not 95RON unleaded. I think this was for the octane rather than lead and that the timing could be adjusted for 95RON fuel at the cost of some power and efficiency but I sold the car before finding out for sure.

I think you should be OK with 98 or 97RON unleaded but a Merc dealer would be able to confirm.

A
Reply to
Alistair J Murray

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