420hp Yanmar's in a 36C?

[ohiohatteras]

Found a killer deal on a pair of RTO Yanmar 6 cylinder 420Hp with gears......wondering if you guys know if they will fit I my 1976 36C?

Looking for any and all $.02......
Thanks

 

[Boatsb]

Found a killer deal on a pair of RTO Yanmar 6 cylinder 420Hp with gears......wondering if you guys know if they will fit I my 1976 36C?

Looking for any and all $.02......
Thanks

Rocket sled is my first thought.

I'd make them fit. Or give them to me for my 41c.

 

[Tim Powell]

Rocket sled is my first thought.

I'd make them fit. Or give them to me for my 41c.

Scott some how i do not belive that was the answer he was looking for. Did the 36 come with 3208 cats at one time. Just compare the two specks. I suspect that will produce a good educated guess.
My suggestion is to check the install price befor you get to excited. Unless you going to get Scott to do it.

 

[saltshaker]

Found a killer deal on a pair of RTO Yanmar 6 cylinder 420Hp with gears......wondering if you guys know if they will fit I my 1976 36C?

Looking for any and all $.02......
Thanks

Call Slane Marine. Give Tom the model # for the engines and gears and he will tell you what the fit will be. That would be a fast runner if they fit. I'd expect slightly better performance than those with the 370HP Cummins 6BTA's.

 

[Boatsb]

Scott some how i do not belive that was the answer he was looking for. Did the 36 come with 3208 cats at one time. Just compare the two specks. I suspect that will produce a good educated guess.
My suggestion is to check the install price befor you get to excited. Unless you going to get Scott to do it.

3208 n yes but not the turbo without raising the deck. The 420Hp Yanmar is a straight 6 and may be too tall. I'm pretty sure the length is no problem.

if you need install bring them here.

 

[Tim Powell]

3208 n yes but not the turbo without raising the deck. The 420Hp Yanmar is a straight 6 and may be too tall. I'm pretty sure the length is no problem.

if you need install bring them here.

Thay is what he is looking. Jack may have had a good idear Tom Has done a bunch of 36 in the past 2 years.

 

[saltshaker]

When I did my repower on the 46C, I would give Tom the model #s of the engines and gears and he'd tell me how'd they fit. I had him do the installation drawings for the yard and they were dead on.

 

[Avenger]

I'd expect slightly better performance than those with the 370HP Cummins 6BTA's.

I'd expect it to keel-walk.

 

[saltshaker]

I'd expect it to keel-walk.

I'm sure it will but don't most of the cummins repowers have the same issue? That can be fixed and is only an issue at high speeds. Each model is different but most can run up to the high 20's or near 30kts before the boat gets up on the keel. What's that number for a 36C?

 

[Boatsb]

Id say the 36 will go a bit faster than a 41 before keel walking as the keel is narrower. I dont know where it will start but Id bet the 420 yanmars can take it there and then some. If you had rear lift rails and tabs it may help but she was never designed to take that much HP.

More of a concern is the stringer system. Is it even close to the task of handling that much HP? I bet it needs to be reinforced.

 

[jim rosenthal]

I think they will fit- aren't the turbos on the sides etc? Either Tom Slane or Tony Athens at Seaboard Marine in CA can tell you. Tony sells Yanmars and he has repowered at least one 36C, although he used Cummins Bs for that one.

It will be very quick indeed. My 36 will do nearly 31 knots and is stable, although I don't think I'd want to go any faster than that. Things would get squirrely.

The Yanmars are no heavier than the 370 hp Cummins. They may even be lighter. Like he said, a hot rod. You might need to go up on shaft size depending on the gear ratio. You can get another 1/4" in shaft size by using thin-wall bearings in the strut and stern tube. Standard issue in these boats is 1.5"- you would need 1.75" shafts, I would think.

There was a 36C-I repowered years ago with 420hp 3126 Cats, and I think Tom knew something about that boat. My recollection is that they reinforced the chines while they had the engine room empty- they built and installed lateral bracing from the outside of the engine beds to the chines. He will remember it, I'm sure. I think the boat's name was Wildcat, but I am not sure.

 

[saltshaker]

Plenty have been done with 370hp Cummins. I would think the Yanmars would be fine from a HP standpoint. Shafts may be ok as the Yanmars are a high rpm engine. All of this is speculation and not enough info to make any accuratet assessments. Talk to Slane as he is doing a 36C right now. I believe they are putting in Cummins QSBs that are around or over 400HP. I'd also contact Al Grovers Marine in Freeport, NY. They've done a lot of Yanmar repowers so they might have some insight for your project.

 

[jim rosenthal]

I spoke this afternoon to one of my friends who used to have a 36C-I. He repowered his boat with Cat 3126s at 420 hp. Used the 1.5" shafts and 1.5 gears. He had no trouble with the setup. With a full load of divers and equipment on board she would still do nearly thirty knots.

I suspect this setup will be fine, and I can't wait to see the sea trial results.

 

[Boatsb]

I spoke this afternoon to one of my friends who used to have a 36C-I. He repowered his boat with Cat 3126s at 420 hp. Used the 1.5" shafts and 1.5 gears. He had no trouble with the setup. With a full load of divers and equipment on board she would still do nearly thirty knots.

I suspect this setup will be fine, and I can't wait to see the sea trial results.

series 1 41c with the same engines, full tower and lots of extra fuel 26-28 Kts
34C with 315 hpcummins 6b 275 gal fuel full water lots of weight 27-28 Kts ( 1.75 shafts)

I see the 420 HP doing more than 30.

 

[ohiohatteras]

Lost the deal on the 420's.....back to looking for a screamin deal on a pair of re-man Cummins....

 

[jim rosenthal]

So you'll "only" go thirty knots..........

 

[ohiohatteras]

I have now found a local diesel guy to assist in the gas to diesel repower. However, I'm sick and tired of chasing down the local Cummins distributor. They don't call back and don't seem to care to take my money. Do any of you guys have a line or contact on a good deal on a pair of factory Cummins remans and trannys? 330hp or 370hp will work.....

 

[34Hatt]

I have now found a local diesel guy to assist in the gas to diesel repower. However, I'm sick and tired of chasing down the local Cummins distributor. They don't call back and don't seem to care to take my money. Do any of you guys have a line or contact on a good deal on a pair of factory Cummins remans and trannys? 330hp or 370hp will work.....

Tony Athens even with him in Ca he will work with you every step of the way he has done it with a friend of mine! He was a Major change like twin engine into a single screw 28' salty dog there is a article on Boat diesel about it. He said Tony was Great and Very Helpful.

 

[jim rosenthal]

Tony, or get the engines from T&S in Crisfield, MD. But Tony actually does repowers and he's a Cummins dealer, too, so he should be your go-to guy. He's done at least one identical boat to yours and mine and knows all the tricks. I would also recommend his Envirovents and his fuel filtration systems, too.

What kind of generator do you plan to get? I might make some suggestions for you.

 

[Tim Powell]

Tony, or get the engines from T&S in Crisfield, MD. But Tony actually does repowers and he's a Cummins dealer, too, so he should be your go-to guy. He's done at least one identical boat to yours and mine and knows all the tricks. I would also recommend his Envirovents and his fuel filtration systems, too.

What kind of generator do you plan to get? I might make some suggestions for you.

Do not forget Roger worthington when it comes to generators he put out some good prices during boat show.