Got the Amberjack in the water yesterday!

[270win]

My wife and I need to talk about it after I get some ideas from the mechanic. I'll share it here, I really think she wants something that'll cruise at 30mph all day long...that ain't happenin' with this boat. But we'll see, she's not being demanding, it's just her preference. Either way I think a big block is the way to go and just sell this fresh 5.7. I'm pretty sure all it needs is a cam and a cleanup.

 

[270win]

Hey Getaway,
what are you getting for wot rpms with that 16x16?

 

[Getaway]

I can hit 4700-4800r's easily. I'll check it again this weekend, but I'm sure I'm right up there, maybe even a little higher. I don't like to rev that BB up that high for long, but she will get there. My sweet spot is right at 2600-2800 and 24-25mph.

With my old prop, 15Px14.5dia, I could run the boat 36mph no problem. The only problem was it struggled to get on plane, then if you cracked the throttle, she would fall off plane easily.

Those big wheels (16x16) push enough water to keep these big heavy boats up on plane at low speeds and pop them up on plane fairly easily. Yeah, you lose some top end, but on the Great Lakes there are not many days you can run them wide open anyways.

 

[270win]

I can hit 4700-4800r's easily. I'll check it again this weekend, but I'm sure I'm right up there, maybe even a little higher. I don't like to rev that BB up that high for long, but she will get there. My sweet spot is right at 2600-2800 and 24-25mph.

With my old prop, 15Px14.5dia, I could run the boat 36mph no problem. The only problem was it struggled to get on plane, then if you cracked the throttle, she would fall off plane easily.

Those big wheels (16x16) push enough water to keep these big heavy boats up on plane at low speeds and pop them up on plane fairly easily. Yeah, you lose some top end, but on the Great Lakes there are not many days you can run them wide open anyways.

I think we'll give that a shot. I rarely like to run over 3K rpms for fuel economy and engine longevity, but I'd want to make sure the bigger prop isn't laboring in the engine. I'm expecting that my boat would never hit 36mph with a single 454 though, the additional beam, depth and weight just induce too much drag.

Money wise, our best bet would be to keep the boat and use it for years to come. I should be talking to the mechanic today about our options. He thinks it could just be a rocker that's backed off, and that's true so I'll let him investigate and get back with me. I'm just glad that I'm not working on it.

 

[Getaway]

I did not notice any laboring of the engine by moving to the bigger prop. In fact, it seemed to make the boat perform like it should. You had to rev the engine too high with the smaller prop to get the boat to perform. Now I get great performance at much lower r's with lots of throttle left.

I have not done a detailed check, but I do know I burn much less fuel than I used to as well.

Keep us posted!

 

[270win]

I did not notice any laboring of the engine by moving to the bigger prop. In fact, it seemed to make the boat perform like it should. You had to rev the engine too high with the smaller prop to get the boat to perform. Now I get great performance at much lower r's with lots of throttle left.

I have not done a detailed check, but I do know I burn much less fuel than I used to as well.

Keep us posted!

Will do! Thanks for the input.

 

[kbsunlovers]

I'm going to +1 on the 16x16 prop. Michigan Match in my case. We're a bit lighter than you, but cruise all day at about 3K and can go as low as 2500 and stay on plane. Planes quickly and WOT with the 5.7 is 4800.

I'll also +1 that you stick with the boat & the 5.7 a bit and see how it settles in as you tweak. I know from your posts that you've got a lot of blood, sweat and tears into the project & you've done things right - experiment a bit and see how you & the wife feel after a month or so. You may be surprised.

 

[270win]

I'm going to +1 on the 16x16 prop. Michigan Match in my case. We're a bit lighter than you, but cruise all day at about 3K and can go as low as 2500 and stay on plane. Planes quickly and WOT with the 5.7 is 4800.

I'll also +1 that you stick with the boat & the 5.7 a bit and see how it settles in as you tweak. I know from your posts that you've got a lot of blood, sweat and tears into the project & you've done things right - experiment a bit and see how you & the wife feel after a month or so. You may be surprised.

I'm wondering how much the added weight and beam of my boat will effect the cruise and planing speed. The 5.7 will get it on plane and hold plane at 2700 with some tabs in.

I didn't get to talk to the mechanic today, they're busy and I'm in no hurry, it's nice to have it out of sight for a short time.

 

[lime4x4]

I have a 1986 268 weekender. Which is a very heavy boat. I replaced the 5.7 with a 5.7 vortec engine. I can run all day at 30 mph at 3600 rpm's. I can keep the boat cleanly on plane at 2800 rpms. Just got back from the cheasepeake bay area. My boat survived what felt like a tornado the first day of our week long vacation. We made 2 non stop trips of an hour long holding the engine at 3600 to 4000 rpm's. and atleast 8 trips 30 minutes long doing 30 mph. I have 100 gallon fuel fuel tank. i filled the tank before putting her in the water. When we pulled out tonight i just have over a 1/4 tank of fuel left yet

 

[KC_Sundancer]

I'll also +1 that you stick with the boat & the 5.7 a bit and see how it settles in as you tweak. I know from your posts that you've got a lot of blood, sweat and tears into the project & you've done things right - experiment a bit and see how you & the wife feel after a month or so. You may be surprised.

+2 on sticking with the 5.7 for awhile. Do a lot of research, the added weight of the big block does not always outweigh the horsepower difference. Some minor performance upgrades on the 5.7 may get you the same results if not better for less $'s. Tough decisions, sit back and enjoy the water.

 

[270win]

I have a 1986 268 weekender. Which is a very heavy boat. I replaced the 5.7 with a 5.7 vortec engine. I can run all day at 30 mph at 3600 rpm's. I can keep the boat cleanly on plane at 2800 rpms. Just got back from the cheasepeake bay area. My boat survived what felt like a tornado the first day of our week long vacation. We made 2 non stop trips of an hour long holding the engine at 3600 to 4000 rpm's. and atleast 8 trips 30 minutes long doing 30 mph. I have 100 gallon fuel fuel tank. i filled the tank before putting her in the water. When we pulled out tonight i just have over a 1/4 tank of fuel left yet

The fuel efficiency of the 5.7 is one reason I liked this boat, we used to run all over the lake all day long at 3K rpms (30mph) in our 1990 220 Cuddy and we would use 25 gallons of fuel.

 

[270win]

+2 on sticking with the 5.7 for awhile. Do a lot of research, the added weight of the big block does not always outweigh the horsepower difference. Some minor performance upgrades on the 5.7 may get you the same results if not better for less $'s. Tough decisions, sit back and enjoy the water.

The more we talk about this, the more we lean toward fixing the engine and selling the boat. I like the idea of the standup head and the size/ride of the boat. But the performance is a big negative for the kind of boating we like to do. When we do stop, we usually hang out on the platform of in the water, the platform on the AJ is not conducive to this as the transom is actually at a negative angle to the platform...not too comfortable to sit on unless you want to lean forward toward the water the whole time. This was something my wife pointed out. I know we could add a platform from swimplatoforms.com, but with the performance negative being as significant as it is, it doesn't seem worth it.

We're talking about taking the bus out west next summer for 2-3 weeks at a time, this would make having the boat in a slip pretty silly...in all honesty, part of the draw to go "camping" is due to this whole boat adventure. Anyway, we'll put the boat back in the water when we get it back and use it, but in all likelihood, it will be listed for sale.

 

[KRB64]

Did you hear back from the mechanic yet on what is wrong?

 

[270win]

Did you hear back from the mechanic yet on what is wrong?

Not yet, I'm hoping to hear something this week.

 

[270win]

The mechanic is going to get into it this week. I just informed him that we just want to fix the current engine properly and sell the boat. For us, this one just isn't what we want. If anyone knows of a nice 1989-1991 220 cc with a 5.7/Alpha setup, that's what we're looking for. Also, I anyone wants a good 84 AJ with a new engine...etc. let me know.

When we get it back from the mechanic we're going to list it and use it while it's for sale. Unless we find a nice 220.

Ill post what the mechanic finds out here.

 

[270win]

Update-
It ended up being a wiped lobe on the cam. I hate flat tappet cams...anyway, we put a stock mercruiser replacement cam in it with new lifters and we replaced the rocker studs because the mechanic didn't like them. End result is that the engine runs like a sewing machine.

I have to admit I was really burned out and just ready to give up on the boat. We listed it for sale and never did put it back in the water this year. It had a few bites on the listing but nothing ever materialized. I was ready to sell it and just buy another hotrod, but the admiral said she'd much rather have a boat than another toy car. That was enough to spark the fire again.

I went to the broker today to pick up the boat and take it to my shop. I did let them keep the listing but I'm asking more for it. If someone wants to step up on a nice boat then I'd let it go. If that happens we'll get something smaller (faster)...but I'm not giving my boat away.

Just wanted to bring this portion of the story to a close.

Moral of the story...sometimes you gotta walk away and take a deep breath. In this case it was 4 1/2 months.