You are not trying to push my anger button are you Bulent? :-)

Paul Lamar

Bulent Aliev wrote:

Oops! I didn't think about that. Sorry.

For those of you new to the list, plugs up is where the engine is rotated 90
degrees with the spark plugs on top of the engine. In the early days when we 
were forced to use the Mazda distributor the engine was lower by running
it plugs up. That is no longer true. Distributors are no longer necessary 
due to electronic ignition. The engine is actually lower right 
side up if the spark plugs and plug wires are taken into consideration.
For a super low engine the water pump can be modified to 
eliminate the protruding thermostat housing. 

The drawbacks were not well understood at the time and several people
have had sever problems. One engine was over heated and had to have a new
rotor housing and another engine seized after 400 hours from no oil 
pressure. I don't know for sure why it lost oil pressure but I suspect
it is because the chain driving the oil pump was not getting proper
lubrication or perhaps the oil pump became worn to the point it lost
prime owing to the fact it was further from the oil level in the sump.
Normally the pump is under the bottom of the engine close to the oil level 
but with plugs up it is on the side of the engine. Fortunately the 
engine seized while running on the the ground.

Other potential problems are improper cooling of the rotors due to oil
drain back problems and steam pockets in the cooling jacket adjacent to 
the spark plugs which happen to be the hottest spot in the engine.
After all bubbles rise. Mazda engineers designed the engine to run 
upright for many very good reasons I am sure. Some of which we may not 
be aware of.

Needless to say I don't recommend the plugs up orientation. 

Paul Lamar
 
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