Mid cabin 1988 repower

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prowlersfish
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Re: Mid cabin 1988 repower

Post by prowlersfish »

Lt1240z wrote: Thu May 13, 2021 6:24 pm RWS you are running zf63 I didn’t think they were strong enough to hold that much torque. I am in no rush but would like to get the gears in the next month.
I am at the boats now redoing skylight windows.
My main curiosity would be the pros and con 1 .5vs 2.0 gear.
Bob states I can only swing an 18 “ prop. Bob did you just change props or shafts too? Prowlerfish what’s the rating on your 6bta’s?
Also Bob what cpu are you running?
Thanks,
Frank
Pro on the 1.5 gear is you will probably will be ok with the shaft. With the 2.0 you likely will have to up grad the shaft.

My Cummins info , Starboard 300 6TBA 300HP@2800 rpm (proped to 2975), port 370B 355HP@3000 (Proped to 3150) ZF 220A gears .
Lt1240z wrote: Thu May 13, 2021 7:52 pm Also the motors I bought were originally stern drive, dampener plates are all the same correct?
No they are not. They must match the gear. Also, gear and bell hosing must match.






.
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat :D
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Lt1240z
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Re: Mid cabin 1988 repower

Post by Lt1240z »

Prowlerfish,
So you are running mismatched motors. Interesting since the base is the same does one have bigger injectors/turbo etc?All mechanical?
As Cummins has a lot of upgrades easily obtained.
Have you tried to match them?
Yanmar seems to be much more restrictive. Seems tractor pulling may be path to wisdom.
Can you tell me the equivalent prop size to RWS 20x20 in an 18”?
RWS can you share some mount pictures etc 😀
Chesapeake Beach MD
1988 Mid Cabin "Tiki Taxi" 454/350s currently....
1996 Carver 310 Santego 383 Strokers Mefi 4
1971 240Z LT4 Mefi 4
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prowlersfish
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Re: Mid cabin 1988 repower

Post by prowlersfish »

Lt1240z wrote: Thu May 13, 2021 10:02 pm Prowlerfish,
So you are running mismatched motors. Interesting since the base is the same does one have bigger injectors/turbo etc?All mechanical?
As Cummins has a lot of upgrades easily obtained.
Have you tried to match them?
Yanmar seems to be much more restrictive. Seems tractor pulling may be path to wisdom.
Can you tell me the equivalent prop size to RWS 20x20 in an 18”?
RWS can you share some mount pictures etc 😀


300 has the older Denso injection pump the 370B has Bosch and of course different injectors. Same turbos ( 300 replacement upgrade s the 300/370 turbo ) as it was replaced. The 370B replace a 300 that blew. No, I have not tried to match them . See no need to spend 15-25k to get another 370B when they are pretty close match as they are. I did however upgrade the 300s cooling system to match the 370.

2.0 gear 3 blade 18x23.5 18x21.7 all cupped

1.5 gear 3 blade 18x14.7 cupped 4 blade 18x13 cupped ad .7 without cup on all
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat :D
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Lt1240z
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Re: Mid cabin 1988 repower

Post by Lt1240z »

So essentially 18x22 cupped is a good starting point with 2.0 gear.
Took out a electric pump yesterday on the 454 to get rid of a delivery problem. SOB would stall out starboard motor at the channel marker every time. Like it knew ! Missed it once by 3 ft second time it did it!
Going to take her out today or tomorrow
RWS did you utilize the existing aluminum mount that is about 4” wide and runs down the stringer or just add too it?
Prowlerfish why not just change pump and injectors?
Thanks,
Frank
Chesapeake Beach MD
1988 Mid Cabin "Tiki Taxi" 454/350s currently....
1996 Carver 310 Santego 383 Strokers Mefi 4
1971 240Z LT4 Mefi 4
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prowlersfish
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Re: Mid cabin 1988 repower

Post by prowlersfish »

Lt1240z wrote: Sat May 15, 2021 9:38 am
Prowlerfish why not just change pump and injectors?
Thanks,
Frank


Because it's not that simple (is it ever?) To change from a Denso to a Bosch pump takes a new gear case, different lines and bracket And of course different injectors. Now the injector spray pattern is different so the Bowl in the position is different. so to do it right new pistons would be in order. A bad mismatch could cause piston failure ( maynot be the case here but .....)

A lot of time and money. And for what gain? A knot or so at wide open? Unless you really know Cummins and the pump you can't tell the difference between the engines. You sure can't tell by running the boat.
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat :D
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Lt1240z
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Re: Mid cabin 1988 repower

Post by Lt1240z »

I see your point.
RWS do you know the size of the trans cooler hose?
Chesapeake Beach MD
1988 Mid Cabin "Tiki Taxi" 454/350s currently....
1996 Carver 310 Santego 383 Strokers Mefi 4
1971 240Z LT4 Mefi 4
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RWS
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Re: Mid cabin 1988 repower

Post by RWS »

I do not know the size, sorry.

Also we bonded and bolted a pair (one per side) of flat aluminum plate to the stringers to better spread the torsional load from the diesels engine mounts.

RWS
1983 10 Meter SOLD after 21 years of adventures
Yanmar diesels
Solid Glass Hull
Woodless Stringers
Full Hull Liner
Survived Andrew Cat 5,Eye of Charley Cat 4, & Irma Cat 2
Trojan International Website: http://trojanboat.com/

WEBSITE & SITELOCK TOTALLY SELF FUNDED
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Lt1240z
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Re: Mid cabin 1988 repower

Post by Lt1240z »

Thanks RWS I used to power steering cooler for reference. It’s 1.5 . I have all the stock at my buddy's I need of aluminum.
Did you utilize the original at all? The Yanmar mount is definitely wider or par with existing plate.
Picking up the gears on Wednesday. ROAD TRIP :P My buddy’s on me to start the Yanmars this weekend . We’ll see.
So I ran Tiki harder than I had ever, opened up the 4 barrels and set her to open buffet. I did grin a bit missed the sound of opening 4 Barrels. Boat impresses me more every day.
I did break the widow on the Carver doing the window seals , a month ago.... I just did the template yesterday.
I feel a little bad, just a little.
Chesapeake Beach MD
1988 Mid Cabin "Tiki Taxi" 454/350s currently....
1996 Carver 310 Santego 383 Strokers Mefi 4
1971 240Z LT4 Mefi 4
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RWS
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Re: Mid cabin 1988 repower

Post by RWS »

Didn't use the Trojan factory mounts or plates at all.

My front mounts included heavy wood blocks, as I recall.

Here's a 2006 photo of the mounting system used

RWS
Yanmar_Mounts.jpg
Yanmar_Mounts.jpg (129.2 KiB) Viewed 8425 times
1983 10 Meter SOLD after 21 years of adventures
Yanmar diesels
Solid Glass Hull
Woodless Stringers
Full Hull Liner
Survived Andrew Cat 5,Eye of Charley Cat 4, & Irma Cat 2
Trojan International Website: http://trojanboat.com/

WEBSITE & SITELOCK TOTALLY SELF FUNDED
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Lt1240z
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Joined: Tue May 11, 2021 10:33 am

Re: Mid cabin 1988 repower

Post by Lt1240z »

RWS
Thank you
As they say a picture is worth a 1000 words. On the mid cabin the mounts ride inside the Stringers , mounted about 4-5 inches down on a single plate that runs al the way to transmission mount one piece.4 -5 inches wide max. Will either bulk it up or make a new one.
Image
I have a whole machine shop/dynojet sitting unused except by me and son-in-law. Sad a lot of power came out of there back in the day. He Tuned the green bomber from fast and furious. They made him stop at 1500hp@wheels leaving a lot on the table. RIP Sr.
Chesapeake Beach MD
1988 Mid Cabin "Tiki Taxi" 454/350s currently....
1996 Carver 310 Santego 383 Strokers Mefi 4
1971 240Z LT4 Mefi 4
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Lt1240z
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Re: Mid cabin 1988 repower

Post by Lt1240z »

One of my motors
Image
Image
Just figured out picture posting :mrgreen:
Chesapeake Beach MD
1988 Mid Cabin "Tiki Taxi" 454/350s currently....
1996 Carver 310 Santego 383 Strokers Mefi 4
1971 240Z LT4 Mefi 4
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RWS
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Re: Mid cabin 1988 repower

Post by RWS »

Suggest you run the valves, replace the timing belt and tensioner while the Yanmars are out.

simple, easy and NOT EXPENSIVE and the parts are available through Yanmar or Toyota dealers or on Amazon/Ebay.

RWS
1983 10 Meter SOLD after 21 years of adventures
Yanmar diesels
Solid Glass Hull
Woodless Stringers
Full Hull Liner
Survived Andrew Cat 5,Eye of Charley Cat 4, & Irma Cat 2
Trojan International Website: http://trojanboat.com/

WEBSITE & SITELOCK TOTALLY SELF FUNDED
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Lt1240z
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Re: Mid cabin 1988 repower

Post by Lt1240z »

Will Do RWS
Went to Harkers
Island NC yesterday,nice place!
Came back with gears
Image
Last edited by Lt1240z on Thu May 27, 2021 1:27 pm, edited 2 times in total.
Chesapeake Beach MD
1988 Mid Cabin "Tiki Taxi" 454/350s currently....
1996 Carver 310 Santego 383 Strokers Mefi 4
1971 240Z LT4 Mefi 4
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RWS
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Re: Mid cabin 1988 repower

Post by RWS »

John Leed requested that I install a VACUUM BREAK when I did the repower.

He also provided the necessary exhaust items to make this work out with my existing system.

I took his advice.

BEST !

RWS
1983 10 Meter SOLD after 21 years of adventures
Yanmar diesels
Solid Glass Hull
Woodless Stringers
Full Hull Liner
Survived Andrew Cat 5,Eye of Charley Cat 4, & Irma Cat 2
Trojan International Website: http://trojanboat.com/

WEBSITE & SITELOCK TOTALLY SELF FUNDED
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prowlersfish
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Re: Mid cabin 1988 repower

Post by prowlersfish »

How is the repower coming?
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat :D
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