MTFCA Forum

Pictured below is a 1918 block I’m taking apart and am down to one stuck piston to complete the task. Now the reason for this post is to point your attention to the extra oblong water hole opposite the usual one, both in the center section of the deck. Has anyone come across this modification - I assume this is not factory.

The aftermarket Reeder heads also have two center section oblong water holes which seem to match up with what we see on this block. I have a high Reeder head and was wondering if mating this head with the pictured 1918 block would have any problems I haven’t thought about, other than modifying the head gasket. I’m collecting parts for a future 1918 TT project. Thank you for your thoughts.

Rich C.

Here are some from last month;
https://mtfca.com/phpBB3/viewtopic.php?t=16419

Rich, I am not alone in having that extra oval hole on a Reeder aluminium head welded up and the head resurfaced after it had warped and blown a head gasket. There being no corresponding passage in the block means the extra hole in the head is superfluous and in fact can cause problems.

Allan from down under.

My Reeder head... Rich C.

My opinion on why the hole on the driver/left side of the engine "should" be blocked off is for proper cooling.

If you notice the exhaust valve arrangement, there are two exhaust valves side by side in the center. That will be the hottest point of the block and need the best cooling possible.

Now notice where the "cooled" water enters the block. It comes in on the left side water intake, headed straight toward the water hole between the two exhaust valves. If the hole on the left side above the water intake is left open, some of the cooled water will rise thru the hole above the water intake and head back to the radiator before it can help the cooling of the two center exhaust valves. But by blocking the hole above the water intake it gives the thermsiphon system the best chance of getting the "coolest" water possible to the area between. The two exhaust valves.

I have always made sure that the left side hole is blocked off. Now that is just my opinion of why the hole should be covered.

My 2-1/2 cents worth...........