YAMATO COOLING 2018..........The Final Chapter.

[Matt Dagostino]

Following up on the optional Enhanced Drilling approved by the SORC last month, ALL Yamato Stock Outboard towers including the 300ssh towers may be drilled to the new cooling spec if a driver chooses to provide additional cooling to their engine. The SORC recently, by a majority vote adopted this 2018 measure. Also the spec of 1.4" has been opened up to 1.5" below the cavatation plate to allow more tolerance for some of the older model Yamato towers.

I have attached the NEW Rule Page 75 showing the 1.5" measurement along with a link to the SUGGESTED Drill Guide that members of the Cool Team and SORC crafted for the do it your-selfer. Chairman Brewster has posted this info also on the APBA Resources page and will soon add it to the rule book link on the APBA site for quick reference.

The Enhanced Tower that was raced in Tabor City will be on display at the Chicago National Meeting later this month with hard copies of the suggested Drill Guide. Members of the Cool Team and SORC will be giving a short presentation on the journey of this project.

Thank you to those involved for making all Yamato's cool again.....

[Flatiron]

Excellent now if someone could solve the availability issue on 321's

[ricmontoya]

We need to get the Environmental Protection Agency to back down on their restrictions. Know anyone that could help us?

[pav225]

Flatiron, have you called TJ to order a motor?

[Flatiron]

I have 2 on order arrival date ?

[ZUL8TR]

How would that work for the Y80, do they have cooling issues at 1/2"?

[Matt Dagostino]

Yes.........we have a couple here in Region 4 that have issues at 1/2inch. You may want to consider drilling just the bottom hole on the Yamato 80 as it has two water holes on the strut! If you drill both you may 'dump' water which may not be cool. We focused on the Yamato 321 and 302 towers during our work over the last 2 years. We did not drill a Yamato 80 tower but suspect that you may want to try just drilling the bottom hole.

[DeanFHobart]

Great work to all of the SORC and the committee who worked on this issue. This should solve the problem.

[Hydro doc]

What about a tool that measures from the prop shaft, removing veriablilty of the cavitation plate.

[Matt Dagostino]

The measuring tool is in production, it is similar to what is shown in the drill guide........... It will be at the annual meeting in Chicago for your approval Doc.....

[ronronx]

I had the same thought that the prop shaft could be a more accurate location to measure from so I machined a tool to fit the prop shaft with a tab that reached up to the bottom of the pickup hole. Out of the six towers I had access to, three of the newer style and three of the older style, four were the same and two were lower by 1/16" to 3/32". One older tower and one newer tower measured low. I then pulled all the gear cases and measured them from the top surface down to the top of the prop shaft with a machinist square and they all measured the same. There is another machined surface on the bottom of the tower you could measure from but I have given up as it appears the pickup hole location is somewhat subject to the Yamato machinist that set up the fixture that day or year. Kyle Lewis, where were you when they needed you.

I still think the prop shaft is an easier and more consistent location to measure from but there will be variables either way.

Best Regards,
Ron McMurphy

[GrandpaRacer]

The 1.5 inch spec is very generous and all should easily pass. Since it cools easily above 1.5 inches there is no reason to push this spec. Hopefully now cooling is no longer an issue and everyone can go back to racing.

[Big Don]

If you measured off the prop shaft and you machined the top of the lower unit it could possibly not meet spec. But who would ever do that?

[ronronx]

No worries Sir, wasn't trying to change anything. Hydrodoc asked a question, I tried to give him some info. Big Don had a question, I tried to answer. Next time I will just send them a PM.

[Matt Dagostino]

All good Ron, was just trying to explain the process we thought through. We wanted to keep it easy and simple. Say hi to Ken for me...)

[Team B&H]

I'm sure no one ever considered that, much less had it machined. It seems to me that it would be much easier to clamp the driveshaft housing to a mill and machine off the gearcase mounting surface than it would be to try and hold the gearcase to have the top milled a bit. Of course I'm just a woodworker, not a machinist! Ever see an inspector measure the height of a driveshaft housing? I bet Edgar never did that!

[Hydro doc]

Thanks Ron.

[ronronx]

Again, just thought you and others might be interested in what I have had the opportunity to witness.

Good luck in 2018
Best regards,
Ron

[Matt Dagostino]

Ron..........thanks for sharing. We also witnessed a few things through the last 2 years that were eye opening! Now as John Adams points out we can hopefully go back to racing and not worry about cooling our Yamato's.