25 replies to this topic

[sonikk4]

What hg have you been using?? Copper or composite

Oh and normally for doing a compression test, all plugs out and throttle fully open.

[gazza82]

When my Midget was poorly it was only running on 1 & 2! You could actually pull the leads off 3 & 4 and it would still idle.

Pulled the head thinking hg and the exhaust valves had bits missing! Probably run too weak at some stage .. but that was one of the easier issues to fix on that car!

Edited by gazza82, 30 October 2020 - 07:38 PM.

[Cooperman]

To do a compression test, you remove all the plugs, fit the pressure gauge to No.1 plug hole, fully open the throttle and spin the engine over on the starter motor for 5 seconds. Then you will have a true reading. Repeat for the other cylinders in turn.

 

However, it looks like although all the pressures look low, which to some extent is because the test was not done correctly, there is a problem with 1 & 2 which is most likely a head gasket.

 

As above, re-lap the valves whilst the head is off the car.

[maystro]

What hg have you been using?? Copper or composite
 

Sonikk4,

 

The first head gasket was a cheap copper one that came in a kit.  It failed so I then changed to a German made composite Victor Reinz after using a stone on the block face.  It was good for about a month.  

I have noticed this Victor Reinz gasket which was recommended to me is not available anymore by Minisport Australia or Mini spares UK.  

 

I had a quality control problem with a German made Iwis timing chain recently.  Maybe all the Krout's are in lock down on the Heineken? 

 

Anyway I have genuine copper Minispares head gasket I ordered from the UK a while ago so I'll see how that goes after  I try and flatten out the block a little more.  

 

Thanks

 

Brad

[sonikk4]

Copper head gaskets especially for the 998 really need the head face and block deck to be perfectly true. I went through all of this with a Minispares Copper head gasket and it leaked fluids even after a full heat cycle and re torque. Luckily nothing internally mixed and the car ran fine.

 

However i knew the head face was true as was the block. A decent straight edge, torch and feeler gauges was used. Old skool and nothing manifested itself. However the HG leaked. There have been numerous people complaining about Copper HG's leaking especially on a 998.

 

There have been other threads on here and FB ref not running water on an initial start up etc etc but i'm highly dubious about that process. Anyway i contacted [email protected] on here and they sent me a composite HG and that was spot on when fitted and run up.

[maystro]

OK we'll this looks to be the problem, blown between 1 and 2.

 

 

This German composite head gasket sure did make a mess of the block and head surface when it came to removing it. It fell apart and stuck in places.

I got a spare copper gasket I'll try.   Does the copper side go top or bottom,  it doesn't say. 

 

 

Also I noticed my number 1 cylinder sleeve is loose so I can pull it up.  This might have damaged the gasket?  

Is it possible to reglue the liner with a cylinder liner sealant such as this.

https://www.permatex...iner/?locale=en

 

Thanks Brad. 

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[maystro]

Here is a pic showing the loose cylinder liner. How are these actually secured into the block originally?
I was thinking of using some loctite 620 which has similar properties to the permatex sleeve sealant. Is this possible?

Thanks
Brad

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[kit352]

I would think it would be nearly impossible to refit that liner properly while the piston is still in place. Anything less than a tear down would be a bit of a bodge job. Ive never seen or heard of a liner being loose enough to pull out by hand. Its quite possibly the source of your tappy noise too which is a scary thought.

Edited by kit352, 05 November 2020 - 12:41 AM.

[Dusky]

Thats scrap/rebuild time. Liners are press fitted. Being that loose is a big problem. Could try oversize liners but probably not worth the hassle.

[maystro]

Yeah well I'm not so sure?  

 

I pulled the sleeve up as far as it would go before losing contact with the compression rings and soaked the bore with degreaser, then a few days later I soaked the bore with thinners.   A week later I smeared the sleeve with Loctite 620 and slowly pushed the sleeve back into the bore whilst turning it to make sure it got good coverage.  I the let it sit for another week.

 

Put on a new genuine Minispares copper head gasket copper side up and now my engine is running great.  Although I think Im probably driving a ticking time bomb?  

 

Brad

[Dusky]

620 is rated for up to 200°C, so that might work. Given that it has atleast 343982N of adhesion force (24 n/mm2, surface area of bore/stroke of a stock 998). That's more than 34 tonnes of force. Might work.