15 replies to this topic

[tomtic]

Got a 'composite' gasket from minimine, there doesn't seem to be any stampings on it. One side is a material similar to the manifold gasket, black/grey with the silver rings. The other side is the steel 'fillet' which is shiney silver, this does not have the rings around the piston.

Any ideas on which way up this goes?!

Thanks

[tomtic]

Just attached some pictures of the gasket.

Attached Files

•  31072007003.jpg   511.19K   8 downloads
•  31072007002.jpg   481.88K   5 downloads

[Big_Adam]

It's an El Cheapo one. Metal rings showing up and then put it one which ever way it fits. Will only go on one way.

Edit

Bulky half to the back, where the push rods are.

Edited by Big_Adam, 31 July 2007 - 07:30 PM.

[tomtic]

Thanks!

Yeah, it's the one that minimine always fit apparently, I said I didn't want a copper one. So black side up then? I was just a little confused as I've always thought the rings go upwards, but I remember something about scraping compound off the block where a gasket had been?

[Big_Adam]

Aye, you might need to scrap it. Copper one don't tend to leave stuff behind but the one you have is basically same stuff as exhaust gasket. Which sticks.

[tomtic]

I've tried the copper ones, and they haven't been too great, so I've taken Guessworks's advice and gone for a composite one.

[Big_Adam]

Ah okay then.

You got the rest of the head stripped already then?

[tomtic]

yeah, it's been in for resurfacing and pressure testing, just rebuilding it all now.

[Big_Adam]

Cool cool, how much the skim set you back. My guy dose it for £30-40 depending on time and how good his day is going.

[tomtic]

Erm, it was £24 for the skim and £24 for pressure testing. That was from A. Yates & Son in Stoke-on-Trent (Fenton).

[Guess-Works.com]

IMO, copper ones are overrated carp....

however, not doing many 998's don't use either very often.... with 1275's there is only one gasket to use and thats a BK450...

[Sprocket]

IMO, copper ones are overrated carp....

with 1275's there is only one gasket to use and thats a BK450...

Unless it fails causing the engine to barf out all its coolant out the exhaust in 500 yards, cooking the paint off the block and melting No2 spark plug electrode. I suspect however, that this was on the German Autobahn, so at what speed i do not know. Both block and head fresh skimmed, Minispares head stud kit and just under 1000miles on the clock, I am devastated. Think there is more to it but wont know untill tonight when i finaly get a chance to have a look.

I will NEVER use the BK450 again after having several leak and after this catastrophic failure.

Many rate this gasket, so im not going to say they are wrong, just my experience

AF460 all the way

[GraemeC]

Sounds bad Sprocket.

However as you say there is probably more to it than simple gasket failure and the AF460 could've done exactly the same.

I've never had a problem with the BK but have with the AF. Horses for courses and personal choice etc etc.

Edited by GraemeC, 01 August 2007 - 11:29 AM.

[Sprocket]

And the beat goes on, la de da de da, la de da de de.


Ho ho ho, the story unfolds.

This engine failure i reported, is not as serious as i was lead to believe, however, it could have been disastrous to the point in scrapping the engine.

Baisicaly, this chap went to IMM in Denmark, when the got off the ferry on the way there, they filled up , only putting about 20 litres of fuel in to top the tank off. However, this fuel station only had 91 octane available so the coctail of 95 and 91, probibly resulted in a final rating of 93, two points down from the minimum 95 that Rover state should be used on the injection engine.

Now then, heres where it gets better. When we built the engine, we built it with the exacting same compression ratio as the cooper engine we used, 10:1. The engine was designed around economy so the non cooper ECU was chosen, normaly run on an engine with 9.4:1 compression ratio. Not normaly a problem with 95 unleaded, but with 93, some where in the ignition map, the engine has gone into detonation, only slight mind as there is no damage to the pistons, block or head. The spark plug electrode has melted and the Waffer thin BK450 gasket fire ring has burned through into the water jacket.

It is likely that the plug was the first to go, and as the plug gap started to close up, it would start to over heat and glow, thus promoting detonation and killing the gasket at the weakest point.

I think the truth will never really be known, other than sub 95 unleaded was used in an engine with EFI that is optimised to run on probiby 97, but happy on 95.

By all means a fairly easy road side fix, if they had the parts

In todays lesson you have learned that European (special) 91 RON unleaded is bad for your engine!

Edited by Mini Sprocket, 02 August 2007 - 12:14 AM.

[GraemeC]

So lucky they had an 'inferior' gasket and self destructing plugs - saved the expensive bits from giving up!