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MG Midget and Sprite Technical - 1500 Head gasket replacement
Started a new thread in the technical section on this: 2 questions. Where to buy a headgasket for a 1500 with recessed bores - will the £12 from Greg at sussex be fine - can you get more expensive and potentially better quality/advanced ones? Do people use a gasket sealant like wellseal on head gaskets? Thanks Chris |
C L Carter |
Chris, just clean it up really well and check it with a straight edge. Clean and check the head surface too. If you can find a Payen gasket, they seem the best. Don't attempt any gasket seal this will just make things worse. Also, make sure you have a good torque wrench, they can be wayyyy out unless calibrated regularly. Last of all, use good quality nuts - get a set of ARP if you can stretch to it. I've blown a couple of head gaskets but it was a combination of crap gaskets and crap wrenches that caused my grief. |
Bob T |
Thanks Bob, I'm on the lookout for a Payen now, I already got replacement nuts and washers during the last build. What I am now VERY confused about is which gasket is correct in terms of the recessed block. Some people have said that ALL 1500s had a recessed block and therefore any gasket sold for a 1500 will have the correct fire rings. (Debs) Some people have said the switch was made in 78 and all they stock is the flat gasket with no fire rings at all?? (greg at sussex classics) Some people are saying the Spitfires 1500 had flat? Some people are saying the early 1200 and 1300 were flat. Some people are saying all gaskets have fire rings... and that some are deeper than others... Some people say that the early gaskets are totally flat (no fire rings at all) Some people have said that the correct gasket has a tab protruding out the side of the engine which indicates its for a recessed bore? Can anyone tell me what is true and what is myth. More importantly can anyone tell me who to buy a decent and correct gasket from. I no longer trust ebay for this... and Greg says his are wrong... My options to me now I think are: MGOC or Moss... or Rimmer brothers... |
C L Carter |
Know how you feel, a murky subject! All head gaskets have fire rings, or you soon buy one that does. But, the thicker ring is not very obvious, until you torque the head down - but then you cannot see the damned thing! I think Debs is right, and all 1500 are recessed (unless they've been to Debs, when they will have been cut flat!) I also seem to recall that the change was in midstream of 1300, as the one I have here is flat, but the one I described in the other thread was recessed, both cars claimed to be 1972; the one present is definitely early 72. Mid-late 1300 is the MKIV Spit, for which there does not seem to even be a parts book. Might look it up here, as they are good and they use factory or aftermarket mfr's parts numbers. I do not recall all of it, but I've always gotten the correct gaskets for whatever I/m working on. http://www.the-roadster-factory.com/ FRM |
FR Millmore |
Might be an idea to ask Debs where she sources hers from Christian I would certainly rate her information higher than most in the 1500 "field" Do you have her number? |
Bill1 |
I remember seeing a John Twist video on 1500 head gasket not that long ago |
Nigel Atkins |
For what it's worth, I'm working on a Spitfire 1500 engine as we speak, and the bores are recessed: http://www.flickr.com/photos/safety_fast/8484345054/in/set-72157632793749760/lightbox/ -:G:- |
Gryf Ketcherside |
The change point was partway through the 1300's, FH25001, 1972 model year. |
Paul Walbran |
Yup, what Paul said. It's the 1300's that were cut flat. The head gasket for a 1500 has to be the correct type for the recessed head. Generally speaking, when it comes to 1500 lumps, Debs is always spot on. Chris, as long as you're just using std CR, all you need to do is use a good gasket, make sure the surfaces are clean and flat and torque it up well. It should be fine. Mine is running at about 10.5CR and thats all good using good quality std parts. |
Bob T |
No I don't have Debs' number. But if anyone can alert her to the post that would be amazing. At the moment the only thing I've found which is definitely PAYEN is this at rimmer bros... quite expensive especially as it is only the HG and not a set... it has a new part number AJM373PAYEN which is apparently a derivative of GUG2546HG which I think is the correct gasket. http://www.rimmerbros.co.uk/Item--i-AJM373PAYEN Debs can you confirm this is the correct gasket for the 1979 1500 recessed block? |
C L Carter |
I got my last Payen gasket from Moss at Feltham IIRC. I'm sure they'll check its a correct Payen type on the shelf if you call them. £20 sounds about right for a quality head gasket. Don't be tempted by a cheapy eBay £10 jobby! |
Bob T |
I rang rimmer and they confirmed AJM373PAYEN is the right one for the recessed block. So I'm placing my order now. |
C L Carter |
I got my last Payen gasket from Moss at Feltham IIRC. I'm sure they'll check its a correct Payen type on the shelf if you call them. |
Bob T |
? Where did that come from? Top job :o) |
Bob T |
So if anyone is interested, I think this is the situation with the 2 types of gasket. Debs correct me if I'm wrong. The early triumph 1300 used a flat (non recessed block) and so used a normal flat gasket. At some stage in the triumph 1300 production they switched to a recessed block and hence a gasket for a recessed head was produced. When they created the 1500 which is used in the midget 1500's they simply lengthened the stroke of the engine increasing its volume and kept the same recessed block. So the same gaskets were used. I believe you can identify the gaskets from a picture, the recessed block gaskets have a tab sticking out the back of the engine. See photo: http://www.aptfast.com/UserData/Images/Large/100899.jpg The non recessed gaskets do not have this tab. See other photo: http://www.aptfast.com/UserData/Images/Large/100902.jpg The tab is a clever idea, it means you can tell what gasket is in your engine without taking the head off. |
C L Carter |
This thread was discussed between 04/03/2013 and 07/03/2013
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