Engine making oil fix

BBlalock · Posted: Tue Sep 10, 2024 11:05 am Post subject:

Thanks for these replies, and sorry for the delay getting back into the site.
1. For clarification, "making oil" is a mechanics term for gas getting into the crankcase and increasing the amount of 'oil' in the engine. Water in the oil is easy to see.
2. The low initial compression and leak down #'s I think was for the purpose of selling a new motor. I watched the second guy do the tests to get good #'s.
3. This motor doesn't have an internal fuel pump and there isn't a diaphragm on it. There is a low pressure pump for getting gas out of the tank to the VST and a high pressure pump in the VST for the fuel injection.
4. If the VST overflows that goes up into the canister which overflows through a tube into the lower engine cowl and into the water.
5. The 'Yamaha' mechanics tech book says 5-6k rpm is normal. I'm at 5,400 rpm. And, yes, 40 mph is not a secure feeling ride with this boat. It slides a bit.
6. As it is now we are 'supposed' to check the fuel pressure regulator this week.
7. If it tests good then I'm going to see about the prop suggestions I received, since that is relatively cheap.
8. Lastly I'll consider the tear down. And I will use a reputable shop to do the work. 610 hrs on it now.
Benton
Sad

BBlalock · Posted: Thu Sep 12, 2024 10:17 am Post subject:

Avidmagnum12 and others:
I just checked my prop and it is a PowerTech 23R16P CL200
This is a bit larger than yours, isn't it? Typically I cruse at 4100 rpm and 26-28 mph. 3.0-3.4 mpg on the Yamaha gage.
Tech is supposed to come today to check Fuel Pressure Regulator
As you can tell by my profile I run 100% at sea level.
Benton

thataway · Posted: Thu Sep 12, 2024 12:21 pm Post subject:

What is the wide open throttle RPM and Speed on your boat with this 16" pitch prop? This is not related directly to the making oil, rather to if there is lugging of the engine, which I doubt.

Thanks.

BBlalock · Posted: Fri Sep 13, 2024 7:59 am Post subject:

A correction on the prop size.
The '23' is actually 'Z' 3. It is a 16 pitch PowerTech doesn't label their props as 14.5x16.
I have sent a request for explanation of what prop I have.

Avidmagnum12 · Posted: Mon Sep 16, 2024 5:58 pm Post subject:

Your boat is probably much lighter than the C-Otter. I’ve never seen over 3 mpg at 26 to 28 mph. We live on ours for 5 months straight and travel remote areas where it could be self rescue or no rescue. Lots of stuff! Your prop is not far off if you get over 5000 rpm at WOT. My goal is to turn 5500 or more at WOT. I trust you with will work out your oil problem. Took a while to answer back as some of the anchorages we’ve been at had no cell service.

BBlalock · Posted: Mon Sep 23, 2024 3:10 pm Post subject:

Update: Tech coming tomorrow to check the fuel pressure modulator. I have a used aluminum 14.5x17P prop ($48.) to try. Also getting the cost of a powerhead if needed.
Still trying.
Benton

BBlalock · Posted: Wed Sep 25, 2024 10:10 am Post subject:

Still waiting to test the fuel pressure regulator.
I did get a turn key quote for a rebuilt powerhead $8,700 with 1 yr warranty. My tech has used them many times and has never had an issue with any of their work.
New motor 3x+.
Ran it 4 hrs and gained 1/8" on the dipstick.
Benton

WCF · Posted: Wed Sep 25, 2024 5:22 pm Post subject: