8 replies to this topic

[alpder]

Just finishing-up rebuilding an A+ 1275. It's my first A-series rebuild.

 

I've come to to put the head on tonight, and I see that the new gasket doesn't align with the cylinders. It misses so badly that on the back of the engine the gasket overlaps the cylinders (by about half a mm) while on the front there's a large gap (2-3mm). There's no spare movement on the studs.

The item is a composite one from BGA... don't have the part number handy but it's listed as being for the 1275.

 

I assume this is a duff gasket? Or am I going to spend £30 on MiniSpare's GUG702560HG replacement... and find that I regret it because it'll be exactly the same?

Also... BGA's gasket is almost symmetric but it has two different oil-feed holes. Like they're options - because only one can actually be used. At one end, the hole has a copper ring. At the other end the hole has a slightly bumpy rubbery surround and no copper. The gasket appears identical top/bottom (and isn't marked) which means you can flip it either way round. Which leaves me asking which gasket-hole goes over the oil hole and which gasket-hole is just blanked? And why the option?

 

Just when you think you're on the home straight, heh. Anyway, late now. Time for a beer while I wait for much wisdom to appear below this post...

[nicklouse]

Post up a picture.

[alpder]

Here we go.

"North" of the red arrows, the gasket protrudes into the cylinder.

The blue arrows show the two optional(?) oil feed holes.

Attached Files

•  IMG_20230209_085150311.jpg   69.9K   7 downloads
•  IMG_20230209_085229883.jpg   71.03K   6 downloads

[DeadSquare]

File the stud holes, 1mm oval.

[Tones61]

fit a bk450

[slidehammer]

Personally I wouldn't use it, I would source one from the reputable Mini specialists. Even if you enlarge the stub holes to position it better there is no guarantee it will stay in place when the head is fitter and torqued down. having an overlap over the cylinder will lead to a hot spot and possible detonation.  

[alpder]

Hmmm... tried filing. Nice idea but it leaves raised edges (and metal filings) so not ideal even if positioning could be guaranteed.

Then, in a belated light-bulb moment, I realised I could try dropping the old gasket onto the block to tell whether the issue is the block or the new gasket.

The old gasket aligns pretty well. So that's settled it: sorry BCA, it's the bin for you.

Thanks all.

[minidave54]

As mentioned above, fit a BK450 (mini spares TAM1521).

I have fitted several and never had an issue.

[Cooperman]

BK450 - always!