Crusaders seem underpowered, 10 meter sedan

[slogfish]

Hello forum. This is my first post here, although I've been lurking around the site for a while. I've had many boats, sail and power, but this is my first twin engine cruiser. I just purchased a 1985 International 10 meter Sedan this past summer. I had been looking at cruisers for a while but I kept coming back to the Trojan since I loved the boat overall. I was reluctant to buy it due to the engines running a little hot and seemed underpowered. But after several sea trials and a lot of back and forth offers, she's all mine and I couldnt be happier, I love the beam and it seems to be built like a tank. The boat fit my needs perfectly and I don't mind doing the work to make this boat great again!
The engines sounded and ran great but they would get up to 220 degrees when WOT. So I knew I would be doing some engine work, I'd like to try to get some more years before repowering. The rest of the boat is in great shape for its age, and no major problems anywhere else besides everything being 30 years old haha.
So I've spent a few months troubleshooting and fixing the cooling issues. I replaced the heat exchanger and elbows on stb, raw water pump on port, and two new 160 stats. I figured once I got it running cool, I would be able to run it out better and get more speed.
Well, I got to cruise about 3 hrs today and port engine stayed at 160 and starboard ran 170-180 degrees. So I'm happy with that! But, I'm still not getting the performance I was hoping for.

I was hoping to see what other similar boats are running. After reading a lot of posts, I was kind of expecting 20-25mph top speed.

Today at WOT I'm doing only about 14.8 mph(gps) on flat water with full 250gal gas and 2 people on board.
Starboard was running at 3500rpm, and port only 2700rpm.
Temps - Stb 180*, Port 160*
Oil PSI - Stb 65, Port 55
I have documentation on a prop job 5 months ago. Props are 18 diameter x 21.4 pitch.
Starboard engine was noticeably steaming from exhaust a bit.
She wants to fall of plane at about 13mph with Stb2600rpm and port3000rpm
Bottom was cleaned 4 months ago but I haven't run it much. I noticed a little growth on bottom today.
I did run this boat up to 18mph one time, right after bottom cleaned and only a quarter tank. I only did it briefly because stb engine temp would get 200+.
I had a marine mechanic check the engines and he was confident they were strong. But have not done compression or diagnostic tests.

I love the boat and I plan on keeping it for many years. I plan to do some Atlantic coastal cruising around NC once I get my confidence on these engines. Any thoughts and/or advice would be greatly appreciated. I'm glad to be now part of the Trojan club!

[kboette1]

Welcome to the Trojan family. Why were you running different RPM's on the engines while running? They should be synchronized when running. That is a huge issue in my opinion. Are the temperatures you are getting on the gauge accurate? You should try to verify the temps with a non-contact heat gun. Did you replace the oil coolers as well as the heat exchangers? you can clean heat exchangers using a product like RYDLYME Marine. Good Luck!

[prowlersfish]

Bottom was cleaned 4 months ago but I haven't run it much. I noticed a little growth on bottom today.
. I'm glad to be now part of the Trojan club!

Welcome to the Forum and congrats on owning a Trojan .

"Bottom was cleaned 4 months ago but I haven't run it much" This is were you need to start Clean bottom and running gear . I assume you have 350hp 454s ?

The Trojan sedan is not and fast boat but should do better . By sedan I assume you mean the fly-bridge model ? Most the 10 meters on here are the express style and mid cabin and they will be faster .Their reported speeds seem to vary some what . A Friend's 10 meter fly-bridge aft cabin would only do 18 knots at wide open , But I believe yours would be lighter and faster . That boat was very sensitive to trim tabs so playing around with those will help .

May I ask where you / boat are located ?

[slogfish]

Thank for mentioning that kboette. Yes the engines are out of synch. That was another concern i fail to mention. Even at idle they are about two hundred rpm difference while throttle positions are same. The difference increases greatly while under way. Would I make that adjustment in the throttle cables or is it electronic? I think there should be more throttle movement, Ill try to adjust them at the carbs next time out. Im still figuring out all the systems on the boat.
I havent replaced the oil coolers but I did remove them and flush with water to look for old impeller pieces. They seemed to free flow fine. I think my temps are under control now with the new heat exchanger and elbows. But what would cause the steam?

Prowlersfish thanks for reply. Yes 350hp, 454s. Im currently near Oriental, NC on the Neuse River. Its brackish water here and very protected. I plan to move to the coast by next spring when I feel confident in the boats reliability.
18 knots would be a great increase over the 13knot top speed im getting. I feel like its barely on plane. I have to keep the trim tabs almost all the way down or the boat starts to plow. The previous owner removed the 2 gas tanks and installed one 250 gal tank under the cockpit. He also removed the Onan and replaced with 10 batteries and a 3000 watt power inverter. So the weight displacement probably shifted more to the rear.

[prowlersfish]

That shift in weight could be a big factor . If you can move the batteries it may help . Do you even need that many ? (that depends on your use )
Bigger trim tabs maybe needed . And I will repeat myself clean bottom and running gear are a must .

[Mahi Mahi]

Slogfish,

By any chance....is this boat the "Sea Cow"?

and if so, did you buy it from a guy named Joe from Ohio?

[slogfish]

Ha yes it is. I guess you know the boat..and Joe?

[prowlersfish]

I believe the boat is a 10.8 meter

http://www.trojanboats.net/wforum/viewt ... 927#p92927

[slogfish]

Ok, Yep I figured I'd run into someone that knew this boat. It is definetly a 10 meter, but the link you posted led me some inverter posts and surveyor that were about this boat. It does have the funky inverter setup. I haven't run the inverter yet due to my skepticism of it. I might go back to the gen setup before its all said and done. It's a 30 year old boat and I knew it wasn't perfect. I weighed my options well before buying. I will eventually update the entire boat to my liking anyway and have a blast doing it.
I spent 3 days on the boat before I bought it. And by now I've seen every crevice that can be found. I can attest to the sellers rigging of a few things on the boat. He is definitely a unique character lol. He scared me off twice but the boat called me back. Ive had over 20 boats in my life, mostly older boats. Several of them I brought back from the dead and passed them on to be enjoyed for many more years. I don't mind tossing thousands into the "hole in the water", gotta spend it on something! The whole thing needs updating, I'll have it better than new. It gives me more confidence in the boat when I know it in and out. I think I was a shipwright in a former life, I just like old boats!

[prowlersfish]

This the link I meant to post . I believe you found it . As long as you understand the inverter issue and handle it I think you will be fine . Look at the alternators to make sure they are approved for " marine gas inboard use "

http://www.trojanboats.net/wforum/viewt ... 1&start=30


Good luck

[slogfish]

I can understand the previous potential buyers worries, I had the same doubts. But I got the boat now and Ill fix her up right.
So now that all the contraversy is cleared up, Id like to revisit the engine sync issue.

How are the engines synchronized? Is it done manually by adjusting the throttle cables or electronically with the sync meter on the console. Ill be back on the boat next weekend and I want to try to get them synched.

Thanks

[prowlersfish]

Just move the throttles until both engines are at the same rpm or using the sync meter , you can try adjusting the cables to get the levers lined up . Unless someone has install a synchronizer getting them in syn is control by you and the use of the controls

[RWS]

you will find my oft posted efficiency chart (when she had gas 454's ) in this link:

http://www.trojanboats.net/wforum/viewt ... efficiency

Your vessel will be heavier and have more windge than an express, but it's a good start.

4 blade props and larger tabs with dropfins made a huge difference for me when I was still a gasoline boat.

RWS

[Drafter]

Slogfish, I have the exact same boat and year. We've been through ours inside to out. I struggled with running hot for a while too. Hiring a decent old school carb man to get things dialed in on the rochesters helped. Found a guy who runs around keeping local high end muscle car collections in tune. Don't expect a 30 year old mechanic to know much about 30 year old carbs that were obsolete before he was born. Both were running really rich. I run out around 30 mph. I cruise around 2800 rpm about everywhere at around 16-17 mph. I almost always run full (242) gallons, and my trim tabs don't even work. Drives me crazy to not keep it topped off. I'm just weird that way, and yes realize I'm dragging 1800 pounds of fuel around for nothing. I am very popular with the jet skiers though.... I took a day to run 3 hours this spring at 3000 rpm with the hatches left at the dock and logged thermal gun readings on everything every 15 minutes. Engines were dead on at 160, even though gauges were 180 plus. Replaced sending units and gauges and that helped a ton. Gauges are notoriously way off. If you're fresh water cooled, go through each component in line one at a time and check for flow. My issue was finally solved by holding a good sized shop vac hose in blow mode on the exchanger hose and blowing out the oil cooler backwards with air. No telling how many impeller chunks have gotten stuck in the oil cooler over 30 years of previous owners. Pieces started flying out that didn't come out with a water back flush.
I can still warm up to 200 degrees if I push it to 4000 for very long and the lake water temp is 85+ degrees. That may just be a need for new risers. All of my risers and elbows are actually still 30 year old originals. Not a ton of 10 meter sedan guys on here. Holler if I can help with anything.

[Paul]

.... I took a day to run 3 hours this spring at 3000 rpm with the hatches left at the dock and logged thermal gun readings on everything every 15 minutes. Engines were dead on at 160, even though gauges were 180 plus...

Keep in mind that the sending units are reading coolant temperature in the cylinder head while the thermal gun is reading the external surface temperature of the engine. The external surfaces will always read a little cooler.