New bravo III props w/ engine upgrade?

Dennis, yeah they both were new engines with BIII drives. I can see where a load would be good during a break in....and a boat engine sure get's one from the 1st hour of service. I love the smell of hot curing paint and the tick-tick-tick as the engine cools on a new motor. Were you breaking in the diesel in your Suburban?
 
Dennis - I guess I was just planning to follow the break-in instructions that are (hopefully) provided with the motor and the sage advice of my mechanic.

Chris - Hoping to have it done in the next two weeks - so it will probably be more like 4 weeks! The good news is the shipping distance is less than 200 miles so I might get to visit the engine on the pallet in just a few days when it arrives here.
 
Congradulations on your 383ci :thumbsup:
Thats a nice upgrade.
 
As far as break in on a fresh motor that has no dyno time...run it at varying speeds for the first 10 hours. Don't be afraid to run WOT but don't hold it for more than about 30 seconds...but do stretch it out some. I wouldn't run at any one set engine speed for more than 10~15 minutes at a time...either fast or slow. Avoid long idle speed times especially during the first 5 hours. Watch all of the gauges closely and be on the look out for water and oil leaks....and don't freak if you see a few...just tighten what is leaking and go on. Watch the oil level and look for any metal that might be on the dip stick (this isn't likely).

Drop the oil and filter after 10...re-fill and take it out and run the be jezus out of it!!

I guarantee one thing...the first time you feel that big torque push when you get out of the hole and the bow falls over...stretch it out a bit and you'll have a grin from ear to ear.:thumbsup:
 
I've got a perfectly good engine but man I really would like to have the 383.

There is a complete 5.0L on ebay (just like mine)....if it brings a high enough price, this is something I may have to consider.

Now all I have to do is figure out a way to convince the Admiral...
 
1stSeaRay said:
Now all I have to do is figure out a way to convince the Admiral...
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Oil drips in the bilge... you clean it up... it keeps coming back. "Honey, I keep cleaning it up, but it keeps dripping again...":smt001 Ummm... Does she read this forum?:lol:

RAB - I totally agree to do exactly what the installer/Merc tells you. I was just wondering about "reality".

Jeff - Yes, was breaking in the engine that's in my Suburban. I lost an oil line while driving. Spun 5 bearings among other things. Had it totally re-built... Better, Faster, Stronger. Luckily, it didn't quite cost 6 million dollars. Lower compression pistons, splayed main caps... next step is a bigger, more efficient turbo.
 
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After spending all day in the shed, acid washing, wire brushing, painting and polishing and not to mention flushing out the remote oil filter lines and fittings, that was a dirty job !! I was so happy to see those 2 movies you posted up. It's so good to see what you are working towards. I've been running die-nuts down bolts and cleaning out holes with a hand taps, so everything will go back like new !

After seeing those "Bad Boys" in action, I can hardly wait to get mine back ! Thanks John, you made my day.
 
Chris Dauth said:
After spending all day in the shed, acid washing, wire brushing, painting and polishing and not to mention flushing out the remote oil filter lines and fittings, that was a dirty job !! I was so happy to see those 2 movies you posted up. It's so good to see what you are working towards. I've been running die-nuts down bolts and cleaning out holes with a hand taps, so everything will go back like new !

After seeing those "Bad Boys" in action, I can hardly wait to get mine back ! Thanks John, you made my day.
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WOW !!! Chris...you "Diggers" really are "hard core".:thumbsup: I love it !! Die nuts on all of all the studs and bolts...and you probably are down in the bilge with a cold Fosters sitting on a stringer grinning from ear to ear !!:smt038

Glad I brightened up your day. I found myself watching both of those more than once also.
 
Rab, now you have the motor out, maybe it is a good time to check your bottom two transom bolts, and change them to SS. They are impossible to get to when the motor goes back in.
This is what I pulled out and what is going back in !

Bolts.JPG


John, I actually had a couple of cans while I watched the movies ! Was at it again today, got that remote oil filter all cleaned up ready for paint tomorrow !
 
Well, as I sit and wait for my new 383 engine install, I am thinking about those props again. I looked up the Sea Ray Prop Charts on thier site and for the 2001 260DA, they list the same B3 props for all of the 5.7, 6.2 and 7.4 engines - which are 15 3/4 X 22 CUP and 14 1/4 /x 22 CUP. The WOT on the 5.7 is shown at 4800 rpms and the 6.2 & 7.4 are both listed at 4600 rpms WOT. The B3 drive ratios are listed as 2.20:1 on the 5.7 and 6.2 and 2.0: on the 7.4. The 4.2 diesel w/ B3 is listed as 15 3/4 X24, 14 1/4 X 24 w 1.81:1 B3 ratio.

Interestlingy, I actually have the 24P props on my B3 (bought the boat used - came with the 24P's installed). I have the 2:20:1 ratio B3. I wonder if having the 24's will give me better performance with the 383 than the 22's would? Or does the cupping on the 22's make them close to the non-cupped 24's?
 
Merc racings site say with the cupped B3 props. You should go one size less on pitch. If your lucky, Maybe you will have the power to cup your 24's
 
RAB, I'm going to stick with my existing 17 1/4 X 23P for the moment which should unload the new 383 for break in. (Bravo II gear box). I'll see how it goes as it loaded up the 350 pretty much so could be OK for the new motor. Also I have a 16 3/4 X 25 in the shed if I need it. I think it will be a bit of trial and error.
 
rabyers1 said:
Well, as I sit and wait for my new 383 engine install, I am thinking about those props again. I looked up the Sea Ray Prop Charts on thier site and for the 2001 260DA, they list the same B3 props for all of the 5.7, 6.2 and 7.4 engines - which are 15 3/4 X 22 CUP and 14 1/4 /x 22 CUP. The WOT on the 5.7 is shown at 4800 rpms and the 6.2 & 7.4 are both listed at 4600 rpms WOT. The B3 drive ratios are listed as 2.20:1 on the 5.7 and 6.2 and 2.0: on the 7.4. The 4.2 diesel w/ B3 is listed as 15 3/4 X24, 14 1/4 X 24 w 1.81:1 B3 ratio.

Interestlingy, I actually have the 24P props on my B3 (bought the boat used - came with the 24P's installed). I have the 2:20:1 ratio B3. I wonder if having the 24's will give me better performance with the 383 than the 22's would? Or does the cupping on the 22's make them close to the non-cupped 24's?
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After the 383 gets some time on it and loosens up a bit you will know. What was the WOT RPM with the 350? The 383 will have enough HP/TQ to best the 350 RPM numbers by somewhere around 200~400 RPM..thats a guess. It could be more...but it will not be less. With the BIII and it's bite the additional RPM will convert to more performance at any RPM as compared to a BII.

If you were getting 4600~4800 from the 350 with your current set up, you will most likely end up at 4800~5000 with the 383....which should be perfect.

I'm thinking also that the 7.4 makes 450 lbs. ft. of TQ and gets mated to a 2.0 gear. The 5.7 makes 350 lbs ft. and gets the 2.2. Your 383 will make a bit more than 400 lbs ft. so you are probably "Bulls Eye" with the 24"
 
Sprink56 - The boat topped out at 4,500 rpm WOT with the 5.7 EFI and 24P props. So I guess it would not be unreasonable to expect the 383 to be able to reach the mid-point of its 4,800 - 5,200 RPM WOT rating. That would give me an increase of something like 500 rpms (like you said 200-400 or better, but not worse). What kind of an increase in top-end MPH should I see with this? Was getting about 39 MPH at 4,500 WOT (on GPS).
 
Ray,

If you only consider the math you can figure that given 40 MPH at 4500 RPM you get roughly 8.9 MPH for each 1000 RPM. With no allowance for additional slipage one could figure 5000 RPM (5 x 8.9) would yield 44.5 MPH. This is all theoretical due to prop efficiency, slip, loaded weight, etc. but should be pretty close. Once you get the engine installed and run it for 15~20 hours you will be able to get a better handle on your particular application.

More importantly than top speed I think you will notice an overall improvement in acceleration, throttle response and the ability to maintain a cruise speed with additional loads. Moreover, it will probably be more fuel efficient as well. :thumbsup:
 
Kind of like getting a new girlfriend. Fun to read about.
 
Spot said:
Kind of like getting a new girlfriend. Fun to read about.
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Yep...know what you mean. It's kind of fun if you can't do it yourself..to live it vicariously through others.

I enjoy someone else experiencing this stuff almost as much as when I get to do it...plus we get to share a lot of knowledge and experience.

I have a fair amount of experience with Chevy V8s and Mercruiser drives...but I don't know "Jack" about marine diesels.... experience wise.

Some of the knowledge/experience on this forum is priceless. For example...if Frank W. says something... you can just about figure it as "gospel". :thumbsup:
 
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Allright, the 383 has landed at the boatyard. I am going up to take a look tomorrow. My mechanic says it is a very impressive motor just sitting on the pallet. He mentioned something about the smell of new paint.
I feel like going there tonight!

Unfortunately, they don't have the right risers they need for the different exhaust manifolds and my particular application - so now we wait for those to arrive.
 
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