• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.

    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

1275 Head to block dowel pins

64nailhead

Freshman Member
Offline
I'm pretty new here so take it easy on me (first post).

I have acquired a 68 Sprite with a 1275cc that was disassembled when I inherited it. I'm in the process of putting it back together. I have a manual by Robert Bentley - The Complete 1275 Manual. I have a question about head to block dowel pins. Are there supposed to be any and in what holes do they go? Each of the holes that look like they could be the correct location are in the coolant porting of both the head and block. I would prefer not to guess and I would also prefer to have my head gasket seal correctly as well - lol.

Thanks in advance for any help you can provide!
 
No dowels.

I am not sure what the current preferred head gasket is. When I last installed one on a 1275 it was the Payen BK450 (composite gasket with a sealant on its surfaces).
 
That explains why I couldn't figure out where to put the dowels - lol.

It had a copper one in the box of old parts when I got, but I got a composite one in the Payen gasket kit I bought. I chose the composite as I've had very good luck getting them to seal in all other builds. Also, I had the heads and deck resurfaced, less than .010" each, so as to allow for a proper head seal. I intended to install the gasket dry, but is there a recommended sealer?

I should also mention that I have new studs and nuts as well - the old studs were horribly stretched.
 
Check specs for torque and tightening order. And the little studs for valve train only 25 lbs or so IIRC.
 
With the black composite gasket you don't use a sealer. With any of the copper gaskets (copper/copper or copper/something) I generally use spay copper on both sides (NAPA??) to aid in sealing the gasket.
I have never had an issue with the water or oil passages leaking.
 
Per Joe's comments, the composite gaskets go on dry. If you use the copper one, a sealer like KW Copper Coat works well. If you don't find KW Copper Coat in local parts stores, it is easily found on Amazon.
 
Welcome aboard -- I have a '69 Sprite. When my head gasket went kablooey, I used the Payen gasket. While you have the head off, you may want to have the blanking plug replaced with a threaded unit. I'll see if I can dig up the threat. It could potentially save you a lot of aggravation down the road.

Edit: Here's the post on the topic on the MG Experience: https://www.mgexp.com/phorum/read.php?1,2096990,page=1#utm_source=alias&utm_medium=mgexperience.net

I'm presuming by your handle that you are also a Buick aficionado?
 
The only time I had trouble with the blanking plug moving was due to sever overheating due to lack if coolant and me not having the brains to pull in at the Glen. My brain fade cost me an engine.
The plug moved due to the extreme overheating and a good machinist repaired. However I have never heard of the plug moving under normal driving conditions.
 
The only time I had trouble with the blanking plug moving was due to sever overheating due to lack if coolant and me not having the brains to pull in at the Glen. My brain fade cost me an engine.
The plug moved due to the extreme overheating and a good machinist repaired. However I have never heard of the plug moving under normal driving conditions.

I would agree -- but if you ever have an overheating situation, why compound it by losing the head gasket as well?
 
Old thread and just getting this together. I had both the head and block resurfaced. The head was pressure tested with no issues. I'm going with it. Hopefully by the end if the month I'll be cranking this up.
 
Back
Top