NEWB Engine Height Measuring Question - TUNNEL HULLS

**wasvette** · 08-11-2016, 06:56 AM

For the Liberator 21 it sounds like the experts (Wildman, etc) reco starting at '1.25" above the pad". Easy enough, right? Well, can someone clarify for me what the reference point is that will be 1.25" over the pad?

> Is it the tip of the sportmaster nose cone 1.25" above the pad?
> Is it the prop shaft line 1.25" above the pad?
> Or something else entirely?

And, one more question - Is the engine height on this 21 Liberator in the video what we're shooting for? Looks like the nose cone is just above the surface (no drag) and the water pick in the water just enough to get good flow.

https://m.youtube.com/watch?v=Enph73GF-d4

Thanks in advance for the education!!! I'm learning slowly but surely which is half the fun.

Kevin

**wasvette** · 08-11-2016, 08:25 PM

So I'm not alone on this? Can anyone help answer what the reference point is that needs to be X" 'over pad'?
thanks!

**John2250** · 08-12-2016, 07:32 PM

I'm also dealing with this right now I spoke with randy and Dave at liberator and it's the center of the prop shaft is my
understanding

**John2250** · 08-12-2016, 07:34 PM

But both are extremely helpful and will answer the phone if you call them

**JPEROG** · 08-12-2016, 07:44 PM

Take a straight edge off of the center pad and the point of your sportmaster (which is the same as your prop shaft centerline) needs to be 1.25 to 1.375 above. If you still have water pressure then keep going up. The higher the case the faster the boat is on top.

Large Dia. propellers work the best on these "typically a 32 Drag 4 insures a 100+ for Randy every time".

Joe

**wasvette** · 08-12-2016, 08:42 PM

Originally Posted by John2250

But both are extremely helpful and will answer the phone if you call them

For sure they are; I just don't want to bother either of them if the info can be gleaned from a post. I'm trying to be respectful of their time as I'm not a current customer.
Thanks for info!!

**wasvette** · 08-12-2016, 08:52 PM

Originally Posted by JPEROG

Take a straight edge off of the center pad and the point of your sportmaster (which is the same as your prop shaft centerline) needs to be 1.25 to 1.375 above. If you still have water pressure then keep going up. The higher the case the faster the boat is on top.

Large Dia. propellers work the best on these "typically a 32 Drag 4 insures a 100+ for Randy every time".

Joe

Joe. Thanks a lot. This is exactly what I needed to confirm. When I go hydraulic, it won't matter as much. But for now, need to know where to dial in the manual jack plate.

**sharpeye Mike** · 08-13-2016, 07:30 AM

Keep in mind that your motor has to be trimmed level with your pad for the measurement to be accurate.

**wasvette** · 08-13-2016, 07:38 AM

Originally Posted by sharpeye Mike

Keep in mind that your motor has to be trimmed level with your pad for the measurement to be accurate.

Thanks - I'll be looking at this today - I think it is close. I'm all the way up on everything so if not high enough it will have to wait until I get a hydraulic jack plate.

**JPEROG** · 08-13-2016, 08:52 AM

Originally Posted by sharpeye Mike

Keep in mind that your motor has to be trimmed level with your pad for the measurement to be accurate.

I should have mentioned that you want to use a level on your running pad and make sure that your cavitation plate is at the same angle. The other variable is the amount of set back that is being used. The more set back the higher you will be able to run and still maintain water pressure. I am pretty sure the slidemasters that Randy uses are 12 inch.

Joe

**dompie99** · 08-13-2016, 06:18 PM

I am confronted with the same issue as this thread. I have an HST with a monster 3.0L V6 and when I bought the boat, is had an Land-and-Sea jackplate that was frozen about 1.5'' above pad. I fixed the engine and tried a few setup's. I installed setbackplates ( 4'' ) and added the land and sea plate ( fixed ) it was good but not as I was expecting, went to 10'' setback with the land and sea, I could go much higher with water pressure. Now, I came back with a Paralift that I start to like very much because over here, there is a lot of shallow water spots and it's ideal for raising the engine on idle to cross those areas. Now, since I fixed the overtemp issue, I am working on the top speed issue.....finally.

**wasvette** · 08-15-2016, 10:45 AM

Joe - So is the video accurate for good engine height or could it be a little higher assuming water pressure still good?

https://m.youtube.com/watch?v=Enph73GF-d4