17 replies to this topic

[MrJenkinsEsq]

Evening all,

Just wondering if anyone else has experienced this problem with a head gasket, or whether it is a problem at all?

I've just had my block back after being machined. It's an ex MG Metro A+, and has been rebored to 1330. I offered up the BK450 gasket that came with my mini spares head gasket kit, just out of curiosity, and noticed that one of the waterways doesn't line up with the gasket. The copper ring actually covers part of the hole. It's the hole next to the 'Front' stamp. Dodgy gasket? Me worrying too much? Don't want to blow the head gasket on my first full engine rebuild!








As always, all help is massively appreciated :)

Edited by MrJenkinsEsq, 23 July 2016 - 09:59 PM.

[Spider]

There's BK450's and then there's BK450's,,,,,,, I gotta say, while I do sometime use these gaskets, i really think they are way over-rated.

 

I know that it's marked FRONT and TOP etc, but try flipping it over and yes, if it lines up, it can be fitted that way, just be sure that the Oil feed hole has a copper sealing ring around it.

[absx2]

I have fitted a quite a few Genuine Payen TAM1521 gaskets ( BK450 ) without issue.

Either you have a Chinese knock off or a wrongly marked gasket but I would guess its marked at the same time the rings are pressed or I just flip them until they look correct.

I can`t remember due to it being a brain off, second nature activity and I have not done one on a 1275 this year but I have never had one back following replacement.

 

 

There's BK450's and then there's BK450's,,,,,,, I gotta say, while I do sometime use these gaskets, i really think they are way over-rated.

 

I`m suprised you find them way over rated as the Payen gasket was fitted to all the Rover minis produced and head gasket issues only seem to arise when a head has been removed and badly refitted with poor quality gaskets or over torqued.

I`m going to guess you use GEG300  and they are a good price. Your experience would be welcome as I got in a load of BK450`s before the GEG300 was produced.

There is also the GUG702560HG  with a rubber sealing ring that "can cause problems"  what the hell 

[Spider]

My first choice is the Payen AF470. These I've found are great BUT only if the deck of the head and block are 110 % or better and studs of the same spec are fitted. Never had an issue with them ever in the 30 years I've been using them. I know a while back, they changed the make up of them, and was a concern, but needlessly so.

 

The BK450 on the other hand, which is a softer and more forgiving Gasket I've had a few let go after a good many miles between cylinders, usually between 1 & 2 or 3 & 4. Almost without exception, when removing a head that's had one of these fitted, there's been evidence of water leaking across the deck and I've seen a few that have leaked out the front. A Mate who swore by them have oil leak problems from the pressure feed hole.

 

The AF470 (and AF460) being a Copper gasket transfer heat better and so the decks of the head and block expand (and move) at similar rates. Not so with the BK450 as they are a heat insulator and this is why they have water jacket sealing issues.

 

<EDIT: The BK450's I've used I'm sure were the 'real deal'. they were packaged in a Payen Packet and in fact similar packaging to the AF470's that I've had such great success with >

Edited by Moke Spider, 24 July 2016 - 09:43 AM.

[MrJenkinsEsq]

How strange! Have flipped it and it's the same. All the other holes line up perfectly, just this one partially covered. The gasket came from a mini spares head gasket kit:

http://www.minispare...ic/AJM1140.aspx

Reckon I'm best off trying for another one from a different retailer in case there's been a bad batch, or looking for an alternative?

[MrJenkinsEsq]

As for the condition of the block and head, both have just come back after being reconditioned and refaced by the wonderful chaps at Southam, so would a copper gasket be suitable or still risky?

Appreciate the input! The only photos online I can see of anything vaguely similar is from those fitting a BK450 onto a small bore block (which this definitely isn't!), with a 12g940 head. The gasket wasn't packaged separately though, it was loose in the mini spares cardboard gasket box. Hummmm...

[dyshipfakta]

Discuss your issue with mini spares if it is a diff gasket I'm sure they will exchange it for you. It may be an issue they are aware of.

[Spider]

As for the condition of the block and head, both have just come back after being reconditioned and refaced by the wonderful chaps at Southam, so would a copper gasket be suitable or still risky?

 

Not sure how those guys finish them. I grind my decks, I think many shops mill them. Even if milled, it still should be OK, however, I'd suggest a little hand finishing with an Oil Stone (a good one). This will also show up the quality of their machine work.

 

I'd also suggest removing the first 1 or 2 threads from all the stud threads in the block. This seats the studs down lower in the block and so when torqued will have a larger zone of influence on the block deck, rather than just localise it around the stud.

 

Lastly, at the very least, make sure all the studs are the same type and not a mix. New ones are best of course, but be sure they are good quality. ARP are good of course but with these, the original ones as fitted from the early 70 to the end of production were very good, along with the flanged nuts. Some new ones I've found are poor quality and can usually be identified when screw them in, they'll 'wobble' around on the UNC thread. Because the 'wobble' this shows the thread is formed not square and so when torqued up, the loading goes down one side of the stud only and they snap - clean with the deck of course!

[MrJenkinsEsq]

Thanks all, mostly wanted to check it's not something glaringly obvious that I'm doing wrong. This is my first large bore engine rebuild, and everything is just that little bit different!

Will definitely give mini spares a call on Monday, check if it's something they are aware of. Love this forum :)

[absx2]

I have just dug out an AF460 and the hole in question is smaller and in the correct place so talk to Minispares.

As Moke Spider says. I just use a countersink bit to relieve the treads on the block.

[Turbo Phil]

Any updates on this ?

Phil.

[RooBoonix]

Just thought I would say, I also had an issue with a headgasket from a Minispares head gasket kit. (BK450). I fitted the head, and the water flowed out the front of the block/head join as I was filling the cooling system up (didn't even have the engine running). Had an old friend come over and take the engine back apart and he confirmed everything I did was correct, we fitted a GEG300 (I think it's GEG300, the copper 1275 gasket from minispares) and I haven't had any problems since.

Head was skimmed but block was untouched (just cleaned up by me). So, after the hype of BK450 HG's I was a bit disappointed!

[Mini Manannán]

My first choice is the Payen AF470. 

 

That's the one I use, it's been very reliable.

[MrJenkinsEsq]

Any updates on this ?

Phil.

Sorry for not getting back to this with an update!

 

Situation is that I compared it to a BK450 bought from another supplier and the two were absolutely identical.

 

I then ordered an AF470 (Minispares part GUG702560HG) and again the hole locations are absolutely identical.  In fact, the only difference I could see was that an oilway has a rubber seal instead of copper.

 

Minispares' response was that 'often the gaskets overlap some of those holes'.  I didn't get a reply after sending the photos.

 

I also had a chat with a friend of my dad's who runs a 1275 historic rally car who had also had experience of that hole not quite lining up before, but hadn't encountered any problems, so I'm going with the 'suck it and see' approach.  I'm going to keep a very close eye on it once the engine is finally in the car.  Unfortunately it's looking like another couple of months before I'm going to get a chance to start it up and see what's what.

 

Will let you know how it goes...

[Northernpower]

Just a thought. If you turn the head upside down how does the gasket look in terms of alignment? If the gasket is off centre with the block will the oil still flow through to the head or does the overlap affect the oil transfer from block to head?