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Re: Overheating and combustion chamber seal

From: bill lock
Fromemail: [billlock@bla-jowett.com]
Category: Technical
Remote Name: 192.168.1.1
Date: 20 Jan 2002
Time: 17:30:13

Comments

keith , I quite agree with your theory. The original aluminium was too elastic both in compression and tension. Perhaps you need to give any crankcase a rest from being pulled and compressed to allow the metal to revert to its original shape for a while before re-use.

I know that many do not tighten the head studs more than 35 lbs ft and are successfull by re-tightening later (i.e. undoing nuts completly and retorquing to the desired level. I t all points to new crankcases being very desirable. i am reaching a conclusion on the specification.

material - hardened al alloy with low expansion and as strong as cast iron. pattern to be very much simplifiedby avoiding most of the recessess & sharp indentations of the to increase strenght of unit. lower entry port for cooling water to allow stronger achor for nearest head stud and cooling water to be evenly distributedover and under liners. large oil galeies with slightly re-positioned inlet from filter housing which I have reluctantly left alone with mike Alfrey,s mod using an AL spacer and o ring seal. all threads will be metric i.e. 5/16 will be 8mm and 3/8 -10 mm, allowing higher torque compression on cylinder heads. And incidentally lowering costs . internal balance pipe will be omitted and an external one provided for by casting extension blocks for cylinder heads plus longer carb studs. If you have any comments please feel free to make them. The cost of a fully machined crankcase including all studs etc will be circa 1250- I will be requesting 600 deposites at NJD 2002. Best wishes Bill Do you wish to avail youself of the Midland Section Annual Lunch on the 3rd Feb price 10.95? it looks like 36 people will be attending.


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