Peninsular 300hp Prop

[DougSea]

This is a request of the guys out there with the 300hp Peninsular in a 28TE:

There's a long back story to my question but it's late and I'm going with the short version. After some repairs due to a prop strike this last summer my engine never turned the proper RPMs. My understanding is that this engine should be turning 3600 RPM at WOT. I'm getting 3200 or less (as the season progressed and I got build up due to crummy bottom paint my speed dropped off)

My prop is currently in the hands of a tuner (Chuck at pitchperfectprops.com in Stamford CT) and while he's confident he can get some of my RPMs back I'd like to know if the right prop is on my boat - meaning I'm not 100% certain the right prop made it back on after repairs. So, the question is - what prop is on your boat? I'm going to try and get a hold of the guys at Albin, and maybe add to that customer service post, but I thought I'd put it out to you guys.

Any information on which prop you have and what your WOT and cruising numbers are would be greatly appreciated, especially if you're running a 3 bladed prop as I am. My boat's a 1997 and I'll dig out the transmission ratio when I get back home tomorrow. If you happen to know yours and can include it with your prop numbers that would be great.

(I'm sure Tomcat has precise numbers but I believe he's got the newer 315 so it's not an exact match)

Many thanks to you all. Think Spring!

[Denis]

I will be heading down to the boat this weekend and I will take the numbers right off the prop. and I will also include the trans. ratio for you. I have a 94 with a 300hp Peninsular with 650 hours on it.
I also had some trouble getting the high rpm numbers last year. I keep the boat fairly loaded so I don't expect it to perform like it was empty but I would get only 3200 wot. I called Peninsular and they had me do a few tests for them such as holding the throttle wide open in neutral and checking RPM. Everything seemed ok to them so I started to empty the boat a little at a time. I picked up 200rpm by taking some of the weight out, it was mostly stuff I didn't need anyway. I will be interested in compairing your numbers to mine. I'll write back this weekend. Denis

[JackK]

Doug -
If it helps any, I have a prop scan report for my prop that I can email.
I don't think it would be useful though because mine is a 4 blade
(315 Yanmar).
________________________
2003 28 TE Dogonit

[jcollins]

Hey Doug,
I think we have the same engine (6.2?). Mine is a 3 blade, 18x18, Nibral.
I have a Hurth 1:56 to 1 V-drive. I seldom run at WOT but I recall it being 3500. If you remind me in the spring I'll check and make a note.

[DougSea]

Hey Doug,
I think we have the same engine (6.2?). Mine is a 3 blade, 18x18, Nibral.
I have a Hurth 1:56 to 1 V-drive. I seldom run at WOT but I recall it being 3500. If you remind me in the spring I'll check and make a note.

Thanks for the info John - I think you've got the exact same setup as me. My survey listed my prop as something other than 18x18 (19x17 I think) but I'm inclined to think the surveyor just read it wrong when he chipped the growth off. The prop I pulled off and took to be scanned is an 18x18. If it HAD been a 19x17 on the boat I'd expect OVER not UNDER revving on the engine.

Jack - appreciate the offer but I don't think it's going to help in this case - different blades and engine power/rpm. Your offer did make me wonder if there's some why to make a 'technical library' available here on the forum. Your prop-scan could be useful to some of the other guys with that engine/prop setup.

Dennis - Sounds like you've got the same setup as me as well. Any more info on your prop and ratio would be great. Also, if you can recall, could you share the tests that Peninsular had you go through? It would be interesting information. I've always been hesitant to run my engine up to high rpms when 'unloaded'. Don't know why, probably the sound of screaming engine without the offsetting wind and wave noise just weirds me out...

[jcollins]

I've always been hesitant to run my engine up to high rpms when 'unloaded'. Don't know why, probably the sound of screaming engine without the offsetting wind and wave noise just weirds me out...

Yes. Me too. Since I'm still a newbie when it comes to diesels I've been hesitant.

[tomcat rio]

4oo cubic inch 310 hp, 2.00:1 hearth gear box, 19x26 four blade nibral.
..
i think it might exceed 3600 rpm at full throttle by just a bit.
.
you might want to get gere's book on propeller theory. somewhat esoteric, but i learned a little.

[jcollins]

4oo cubic inch 310 hp, 2.00:1 hearth gear box, 19x26 four blade nibral.
..
i think it might exceed 3600 rpm at full throttle by just a bit.
.
you might want to get gere's book on propeller theory. somewhat esoteric, but i learned a little.

Help me learn something here. They are both 6.2 liter engines. Both 400 c.i. What makes the 10 HP difference? Just the year manufactured?

[DougSea]

Help me learn something here. They are both 6.2 liter engines. Both 400 c.i. What makes the 10 HP difference? Just the year manufactured?

To make it more interesting - boatdiesel.com shows the older Peninsular 400TA as making 280hp - so it's a 30hp difference. Go figure. Good time to call Peninsular perhaps?

[Denis]

I would assume it's a change in the fuel injector pump and especially in a different boost in the turbocharger. Small changes in boost can affect hoursepower output dramatically.

[tomcat rio]

quite an HP spread for the same basic engine...the current engines are not built by GM . american general bought the rights and did some changes.

http://www.amgeneral.com/vehicles_gep.php
....
peninsular uses their own pistons. the same engine is also available with a super charger vice turbo charger from a different manufacturer.

...http://www.peninsulardiesel.com/marine.html

[Denis]

Doug, I went down to the boat yesterday to get some numbers for you. The prop. is an 18" x 18" LH NiBral three blade prop. The trans. is a Hurth HSW 630. The ratio is listed on the plate as V1 - 1.56 - 1.57. Im not sure what that means but that is what is typed on the plate. My WOT with the boat loaded is about 3,300. It cruises very nicely at 2,200 rpm making about 20 knots. I think I would like to get a few more rpm,s at the top end but Im not sure if it is worth the trouble.
Peninsular asked me to perform a few tests last year. After warming the engine up he said to peg the throttle and check the rpm in neutral. The governor should hold the rps,s at between 3,800 and 4,000. That worked out fine. He said to make sure the bottom was very clean and to run Stanadyne diesel fuel cleaner through and to run a Stanadyne lubricator. If I wanted to make a change that I should try to take an inch of pitch out of the prop. to reach the 3,600 suggested. Hope some of those suggestions help. Denis

[tomcat rio]

but you might want to double check the numbers.

[tomcat rio]

i.e . the engine is turning 1.57 times as fast as the prop. one number is in foward and the other is in reverse. the ratios are very close.
...
i have a hurth 2.00:1. so, at 3600 rpm the prop is doing 1800 rpm.
i chose this ratio because it allows a wider variation in prop pitch, diameter and blade variations.

[DougSea]

Doug, I went down to the boat yesterday to get some numbers for you. The prop. is an 18" x 18" LH NiBral three blade prop. The trans. is a Hurth HSW 630. The ratio is listed on the plate as V1 - 1.56 - 1.57. Im not sure what that means but that is what is typed on the plate. My WOT with the boat loaded is about 3,300. It cruises very nicely at 2,200 rpm making about 20 knots. I think I would like to get a few more rpm,s at the top end but Im not sure if it is worth the trouble.
Peninsular asked me to perform a few tests last year. After warming the engine up he said to peg the throttle and check the rpm in neutral. The governor should hold the rps,s at between 3,800 and 4,000. That worked out fine. He said to make sure the bottom was very clean and to run Stanadyne diesel fuel cleaner through and to run a Stanadyne lubricator. If I wanted to make a change that I should try to take an inch of pitch out of the prop. to reach the 3,600 suggested. Hope some of those suggestions help. Denis

Dennis - Thanks very much! It looks like we're running the exact same setup. Between you and John I feel much more comfortable that the right prop made it back on to my boat after the repairs this summer. Now if I could just figure out what they did with my 200 RPMs!

Did Peninsular say anything about your WOT numbers? Every book I read about diesels says it's important that the engine reach it's spec'd RPMs at WOT or you're putting too much load on the engine. I'm really hopping my prop guy can get me back up to at least 3500, 3600+ with the boat running light would be even better.

Really appreciate the additional feedback on unloaded RPMs and the fuel treatment. Also considering having my fuel polished before this season - who knows what sits at the bottom of my 10 year old tank.