Cummins 480CE Props with New Heads?

[Ray Isaac]

Good morning everyone,

 

Good morning everyone,

 

I have a 2005 Sea Ray 420 Sundancer with the Cummins 480CE engines. Before last season I had the heads replaced, after cooler cores replaced,  new injectors, new water pumps installed, and new turbos being installed this spring. I’ve done all this as a “1000 Hour Service” process as well as to eliminate the “dropped valve” issue. While running on my existing props the fuel burn was below the curve and numbers suggested by Tony, and the boat easily hit the rev limiter. The existing props were 22×25 (one was de-tuned from 27) and I believe I was running at about 2 – 3 mph where I should be at cruise. In September I ordered new Veem Conquest 22×25 props with a slight cup, hoping I could sea trial those before the end of the season. They did not arrive in time to do that (I just received them this week) and after discussions with the prop shop I decided to go with a 22×26 without any cup. We agreed on this since they advised me that the cup was equal to 1” of pitch anyways. I plan to install these this spring and sea trial to get GPH, RPM, and MPH figures. My question is since I now have the new style factory heads is the fuel burn and EGT still as big an issue for longevity? I’m cautious of doing any damage to the motors but also would like a little better performance, which I’m sure the new prop design, let alone the slight pitch increase, will provide. Additionally, is there anything else I should be looking for at sea trial or any other things I should be observant of?

Thanks in advance for the help. This forum and  have been extremely helpful. 

Topic

[Steve Lewis]

250watt oil pan heaters.  When we had the heads installed, we had the mechanic put them on since he was down there.  They run on 110AC.  Shorepower.  I have an outlet in the engine compartment that is on the bulkhead right above our battery box.  I plug them in there.  I typically let them run about 24hours(or more if possible) and they warm the engine from the bottom up.  They heat the underside of the oilpan so the heat conducts up the whole engine if they are on long enough.  The engine compartment feels nice and warm and dry.  Does a very nice job of pre-warming everything.  Engines seem to start easier and the exhaust smoke is minimal.  I feel like a better dock mate now that we don’t smoke out the neighbors when we fire up to head out.

SBMAR sells them.

[Ray Isaac]

Steve, curious – what are the “Wolverines” you installed?

[Ray Isaac]

Thanks for the feedback Steve and yes, let’s stay in touch to share notes and experiences. My personal email is [email protected]. I attached a picture of my readout at 2260 RPM’s  

 

[Steve Lewis]

Ray,

I think we should stay in close contact.  We have now run our boat with the brand new heads a few times this season.  We had beautiful weather this Memorial Day weekend so we were able to run to our favorite hang out anchorages around the Lake Erie islands and I kept an eye on things.  Here is what we are seeing:

2220rpm, 29gph total, 22.5 – 23mph depending.  Coolant temps are the normal 159P and 165S.  We have seen a change in EGT.  We are now 750P/700S which is “more or less” a flip from last season.  I am going to guess that this can be written off to tolerances…….   I am happy to run the engines from 2200 – 2300 depending on conditions but mainly settle in the 2220 – 2250 range.  2260 should be no issue and since we both have the advantage of being in cool fresh water, our engine cooling is at an advantage. Our depth sounder has a temp sensor on it and the water temp in the open water of Lake Erie is 60F.

We finally have our wolverines installed and I have started to use them.  Not sure about yours, but when our engines started COLD they tended to smoke.  The wolverines have made engine starts much easier and they barely smoke now.

You seem to be right on the curve and we are a touch over the curve.  We both have the new heads so I think we should stay in touch and compare notes as we run these in and gain real world experience.  Our summer trip in July is to Traverse City, MI.  That is about 4-5 reasonable days of running in each direction.  I will keep a detailed captain’s log and share along the way.  

[Ray Isaac]

Performance readings with the new props

Good Morning Tony,

Thanks as always for the previous guidance on this forum. I finally had a chance to get the boat out and try the new props this weekend. As a reminder I installed Veem 22×26 props with no cup. My performance on these was 13.7GPH Port and 13.2GPH Starboard (the engines seem to always vary side to side by about .3-.5 GPH, even at idle) at 2200 RPM. I was running at 162 degrees on both motors and speed was around 24.5 MPH. At full throttle the engines wound up to 2674 and I was burning 23 GPH at that RPM.

Question; at 2260 RPM I was burning 14.3 GPH and the boat seemed to run perfect and I gained a little speed as well. Temperature is never above the 162 and I have now replaced the heads, aftercoolers, turbos, raw water pumps, and injectors. Would 2260 be an acceptable cruise RPM?

Thanks again Tony for all your help!

 

Ray

[Ray Isaac]

The paint I ordered is;

Cummins PAINT WHITE 3885909 – Marine Parts Express. … 3885909, PAINT WHITE, Cummins, $ 13.48<br />It seems to match perfectly on the 480 CE

[Steve Lewis]

Paint Options

Correct cummins paint

 

[lpmcc]

Do you have a part # for the factory paint?

[Ray Isaac]

Here’s a shot of the engine after last season. 

[Ray Isaac]

Paint

Steve,

I used the Cummins factory engine paint and it didn’t discolor at all last season. The only place there was some scorching was at the exhaust manifold connections to the heads, but that’s to be expected. The turbos, aftercoolers, etc all looked fresh at the end of the season. I used it again on the new turbos and I’m expecting the same results. 

[Steve Lewis]

RD,

Ditto with Ray.  We did proactive/preventive replacement of heads, raw water pumps, fuel filters and had our cooling circuit serviced when we bought the boat(Apr 2021) and then again when the engines were torn down for the head replacements(winter 2022/2023)……….  we are in Lake Erie so fresh water and everything looks good even though we have some marine age, but relatively easy marine age.

A very heavy ounce of prevention……  The cost of the preventive fix is about half of what a total catastrophic implosion would cost to fix.  We knew that going into the purchase and offered accordingly.  We splash in a week and will sea trial the heavy work with our mechanic and then get humpty dumpty put back together again.  Cockpit decking, furniture etc……..

The 460 that we have is heavier than the 420 so our fuel burn is a little over the 450 curve  even after 2 inches of pitch removed.  I will live with that based on the new heads and our EGT base line from last season.  

I will use some kind of chemical paint remover on the turbo air pipe, rinse excessively, dry and then paint with high temp white paint.  Rob Schepis has many posts on what products to use.  It will be interesting to see what discoloration I get based on our current full cruise load.

[Ray Isaac]

Richard,

I did the heads as a precautionary measure given that I am not the original owner of the boat and I’m not sure how it’s been driven in the past and how hard it’s been pushed. I figured the ounce of prevention (expensive ounce) was much better than the pound of cure. I also did the aftercoolers and injectors as well, and I just replaced the turbos this spring. I like to have confidence in the power plants because we often take extended cruises. 

[Richard Dodson]

Paint

Out of curiosity what were you going to use to strip the dark paint. 

[Richard Dodson]

Head swap

Just curious, was the head swap prior to your purchase done as a result of a dropped valve seat ?  

[William Walter]

New heads

Ray I have a 38 tiara open so my numbers probably would be of little use to you.The 38 open with mechanical engines was propped 28 by 24.when tiara put the 480 ce in they propped it 30 by 24. The extra 2 inches probably killed those engines in tiara’s at least. I am am probably still over propped at 29 by 24.I’m still over propped but I really don’t push the boat as I burn 12.8 gallons at 2100 rpms.The boat moves along at 21.5 knots. The boat never exceeds about 65 percent load in all sea conditions.Unfortunately as the season goes on those numbers go up but the boat moves along nicely at 2100 rpm’s.Bill 

1 user thanked author for this post.

Ray Isaac

[Ray Isaac]

Steve, You’re definitely looking at the right criteria of cruise statistics. As Tony says, most of the usage and wear and tear is at cruise RPM’s so that’s what I’m going to focus on. I’m running ZF 280 IV with 1.561:1 ratio so I’m geared a little lower than you. Probably acceptable given the lower weight of the 420. <br />Thanks again for the dialogue- this is helpful  

Ray

[Steve Lewis]

Ray,

WOT was not the issue.  Hit the gov from the get go.  It was cruise fuel burn I was worried about.  The engines had 590 hours on them and previous owner ran them hard so I was worried about dropped valve seats.  Turbos and air pipes are dark.  So I wanted lighter load at cruise rpm’s.  I took care of loading first then replaced heads.  Just for fun I might remove the dark paint on the port side air pipe and repaint to see what kind of discoloration happens with our loads.  Port side is the easy access side for us.  We splash in about 1.5 months. <br /><br />I have ZF 280IV with 1.77 reduction gears.  What’s in your boat?

[Ray Isaac]

Thanks Steve for the thorough response. The 460 is definitely a bigger boat than the 420/440 (and a beautiful boat as well. I wanted one but couldn’t find a nice one when I was looking to buy). I would suspect that there is probably a light cup on your current props – it seems every shop always puts a cup in because of the performance advantages.

I’m going to install the 22×26’s and do some performance tests this spring, the first being a WOT test to make sure it achieves the factory rating. Then I’ll examine EGT and GPH as well. With the 22×27’s that you had on, were you able to reach the factory RPM at WOT? What was the WOT RPM with the 26’s and now with the 25’s?

Ray

[Steve Lewis]

Ray,

The original spec on the HyTorq props when we bought was 23×27 with “H-Cup NI” stamped on the prop in our survey pics.  That is factory spec for the 460Dancer.  When we ran the sea trial we had 300gal fuel(3/4 tank) and probably 20gal of water, 4 people and no gear.  The fuel burn that I focused on was 2200rpm 30gph and we recorded 23mph speed.  Remember we are a larger heavier boat than yours for comparison purposes.  After we reduced pitch to 23×26 AND loaded in all of our stuff we ended up with a cruise of 22.5mph @ 2140rpm and 30gph burn.  That was a step backwards but as Tony pointed out to me in previous posts, the test conditions changed materially.  Over the winter of 21/22 We took another inch of pitch out and arrived at our 23×25 dimensions.  I do not see any reference to cup on the computer reports.  I have had it in the back of my mind to call them and see if there is any indication in their systems of cupping……

So we are now at 23×25 and ran the entire 2022 season with those dimensions AND EGT.  So we are now running 2220rpm, 22.5 mph and depending on conditions 29-30gph total and 725F/750F on EGT prt/strbd.  This is with FULL Cruise load which is 300 gal fuel, ~25gal water 2 humans+1dog and 2 weeks worth of food, clothing, folding bikes and other things.  We are heavy in that configuration and still over the curve. 

This off season we did the following:  sand blast then barrier coat and finish coats on the bottom paint.  New Cylinder heads(4942463) and raw water pumps(SMX).  We also had the cooling circuit serviced again since the engines were apart.   

I am going to update the Project thread I started a while back once we are in the water and running and can update things with real world data.

[Ray Isaac]

Thanks for the replies Gentlemen. I have a couple of follow up questions:

William, what boat do you have and what props are you running? Do you have any operating parameters that you’ve compiled; EGT, GPH, Curve, etc.?

Steve, what were you seeing for readings with the 26” props and now with the 25’s? We’re those straight or did you have a cup on them?

Thanks again, this is very helpful. 

Ray

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