1987 Ski Centurion Tru Trac II - First Time Rebuild - Floor, Engine, Dash, etc.

[ACon977]

I've read the forum boards on this site a lot over the past couple years in preparation for my own rebuild, and finally found a boat to work on! I've been around boats all my life, but never something that needed an overhaul like this one. Very excited for the challenge and opportunity to learn.

Looks like the engine has had some work done to it previous to my purchase (plugs, wires, carb, starter has some new wires, hoses, etc), but it has been abandoned for quite a few years. Needs to have the seats, deck, dash wiring, and block touched up. Hoping to pull the engine, replace freeze plugs, and JB weld a small crack in the block to avoid a full engine rebuild. Hoping that the engine isn't seized, (if it is, it's the debate whether or not to try it myself). Then onto the floor, again hoping that we can just tear it up, and reglass and lay new boards, rather than doing the stringers. And finally the seats, engine cover, speakers, and gages in the dashboard.

Should be a fun project, looking for whatever advice or experience people are willing to offer. The more buzz this generates, the more pictures and such I'll post. Attached are some images of the boat when we bought it.

Cheers!

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[garbageguy]

suggest looking into show-stoppers (you define those for yourself) before putting any money into it. Got any pics? I think you just need to have 3 posts before you can upload them into your posts

 

[Big Gee]

Looking forward to following along!

Sounds like an interesting project.

Can you try the pictures again? :thumb::thumb:

 

[ACon977]

garbageguy I tried to upload pictures with the original post. I can see them. I have attached some to this post as well.

Show stoppers are definitely something that I've thought a lot about, but after buying this for $700 I'm not too worried about spending some money on it. Worst case is I have a shop rebuild the engine and then the rest I feel comfortable doing. i just had a friend redo his floor and dash.

I've already inspected the hull and there are a few rub spots but no holes. The seats are weathered, not sure if the frames are trashed or not, but wouldn't be opposed to building some new ones. The floor is rotten, haven't pulled it back to look at the stringers, but am being hopeful.

My biggest worries are regarding the engine, but I have to pull it in order to truly figure out what is necessary. From what I can see, and I can post pictures, is that there are a few plugs that are popped, one small crack next to one of the holes, that from other threads, i am going to try and grind, and repair.

 

[ACon977]

some pics of the freeze plugs

 

[ACon977]

Some extra pictures of the engine that I took

 

[Woodonglass]

I'd be surprised if the engine doesn't need major work. I'd also wager that the stringers, motor mounts and transom are bad. In other words a Total Gut job will be required. But you can always Hope for the best but...Prepare and Budget for the Worst. Motor work and Gut job could run in the $4-5 K range. How's the trailer?

 

[ACon977]

Woodonglass We were hoping to budget for 3-4k on the rebuild, doing most of it ourselves. If the engine needs major work then that would be the extra 1k that would get us to your range. What would be some tests I could run that would help to determine if it needs to be completely rebuilt? Ive seen people rotate the shaft from the front pulleys, after you remove the spark plugs, other people have taken the heads off and checked the pistons for rust.

The trailer is actually in decent shape, I would like to rebuild the bunks, but the steel is solid and the tires are semi new with a spare.

 

[ACon977]

Over this past week I put together a gantry hoist system that I had found from Frank Howarth, who has some cool design and build videos and has been using his for a long time. I reinforced mine in a few more places than he did, but overall same concept, and am pretty happy with it.

https://www.youtube.com/watch?v=PtPU1pOTLH4&t=64s

The biggest question is with the lift, I bought a 2 ton capable rope pulley and straps to hook to the engine to lift it out of the hull. Im not too worried, and have a trailer crank which I plan to mount to the 4x4 uprights to hold onto the rope.

Below are a few pictures of the finished build.

PS: In other exciting news, after re-inspecting the engine I found that there were no cracks in the block at all, although it is still rusted out on the inside, it was actually a piece of a sealer or gasket from a freeze plug that made the block look cracked in the picture. Still tons to do on it, but the first bit of good news in the project.
I am hoping to get the engine mounts detached, test the hoist, and pull the remaining freeze plugs and try to get a better inspection of the engine block rust.

I purchased some rust remover (https://www.amazon.com/gp/product/B005JVNQPQ/ref=oh_aui_search_detailpage?ie=UTF8&psc=1) that I had read other people used to "wash" the rust out of old abandoned engine blocks, and then also purchased Marvel Mystery Oil to put in the cylinders to try and ease the pistons and rings. After a lube and wash, I'm going to try to turn the engine over with the flywheel and a breaker bar. If that fails and the engine is seized, then I need to decide if I want to attempt to rebuild it myself, or put it on a trailer and bring it to a shop.

Any comments or advice is appreciated! I'm going to push through on this project one way or the other.

 

[Bayou Dave]

Great job on the gantry!

 

[devildogae]

I think your on the right track. Hopefully the rust is just in the water jacket, and not the cylinders. Get any kind of motor oil into the spark plug holes and turn the crank nut with a breaker bar, longer the better. Make sure the boat is in neutral when you do this, or you will be trying to rotate the drive system.

Do you have any engine building skills? If you tear it down, it would be advised to take to the machine shop and have them clean it and check for cracks. If the motor turns freely, do a compression check and leak down test. That will tell you a lot about the health and potential of the motor. That's where I would start.

BTW that a good looking engine hoist, nice work.

 

[ACon977]

Do you have any engine building skills? If you tear it down, it would be advised to take to the machine shop and have them clean it and check for cracks. If the motor turns freely, do a compression check and leak down test. That will tell you a lot about the health and potential of the motor. That's where I would start.

BTW that a good looking engine hoist, nice work.

DRS4164 and devildogae Thanks for the compliments on the hoist. The rope hoist worked to pull the engine out but I wasn't able to hold the weight with just my fingers on the rope, shouldn't be any surprise there.

So I went to Home Depot and bought a strap puller which replaced the pulley, worked like a charm and I ended up getting the engine up and out. From there I was able to remove the motor mounts and clean out the freeze plug holes and pop out the ones that were still in, the block is still looking like it is in good shape (from the outside) which is a great feeling.


I don't have a tremendous amount of engine experience, rebuilt carbs and new alternators, radiators, etc. but this could be my chance to learn a lot. If I go to the trouble of tearing it down and re-ringing then I would definitely take the block to a machine shop for them to clean it up and rebore the cylinders. Im sure it could use it, but not sure if I want that to be a thing after we have the boat in the water for a season.

After getting it out and cleaned up a bit I tried turning the engine over by hand and to my surprise, it rotated!! Not smooth and silky but it did rotate, which was a huge relief. So I added some Marvel Oil to the spark plug holes and kept rotating the engine until it was rotating relatively smoothly.

Looking at the plugs, cylinder 3 and 7 both had some carbon build up, the rest looked pretty good,

My next thought is to pull off the heads and look at the risers and valves to make sure that they have a full stroke. I think it may be worth trying to hook up a battery to the starter and see if it wont at least turn over for me. Then a possible compression test, or at least a leak test on each cylinder. Results of these 3 things will determine buying an engine stand and start tearing into it, or just put in new plugs, wash out the inside of the block to get rid of some rust, and do the rebuild at a later point.

As always, thoughts and comments are greatly appreciated!

P.S. My phone and camera died on Sunday night when I did all this so I didn't get good pictures, I will take some more tonight and then post them after I work on it a little this week.

 

[boedekerj]

IMO; I would scope it to look for scoring in the cylinders before you put too much into it that block, man. Google search "borescope camera for android". they're cheap. If you take a peak in each of your cylinders (at bottom) make sure that you still see good and distinct cross-hatching and no hazing or vertical scoring. This happens sometimes if debris/corrosion get's into the cylinders and you rotate it. If the cross-hatching is gone or its scored or hazed, you're going to have a smoky-blue haze that never goes away.

 

[ACon977]

boedekerj Thats great advice, I will be sure to get one of those on order. I would bet that the cylinders are not clean and pretty, its an '87 after all with no rebuild that I could guess having taken place.

Tell me if I'm wrong but wouldn't that be similar to a leak down test? Telling me that my cylinder walls are scraped out and I would need to have them worked. I know the engine isn't in great shape, but I'm more just trying to make sure that it's functional.

This is why Im debating getting it functional first, rebuild the floor and seats, and then tackle the engine at a later point, next year or so. Not trying to be lazy, just give me some motivation to get working on it faster and take smaller chunks. of the project at a time.

 

[boedekerj]

Ya know, I guess it would? I can think of a couple things it may not catch, but overall, I think you're right. Compression test may be a fine overall test.

Personally, I'd focus on the hull first, but that's just me. Whatever you can do to stay motivated, man.

 

[Ned L]

Since you have it turning over I would agree about getting it running. I suppose before trying to start it you could pull the valve covers just to see that the valves are all doing what they are supposed to.
Why pull the heads now?
I would do a compression test ONLY to see there is something in each cylinder and not even look at numbers until after it has run for a while under load and gotten good and warm.
If it starts, runs and idles decently what more do you want? It sounds like you want a boat to have fun with, you’re not going after a top performing race boat or heading 200 miles offshore for some fishing. There is a lot between a new fresh engine rebuilt to specs and one that is so worn that it will give chronic problems.
....sitting for a couple of years doesn’t necessarily mean anything. Those core plugs admittedly aren’t a good sign but you might be lucky.
Looks like a fun project.

 

[Scott Danforth]

the fact that the core plugs are out would scream improper winterization. assume your going to be looking for a block, heads and exhaust. I would look for a 351 out of a low mileage truck and plan on swapping your marine accessories, rotating electrics and tin over if you want to stay within your really low budget.

 

[ACon977]

Ya know, I guess it would? I can think of a couple things it may not catch, but overall, I think you're right. Compression test may be a fine overall test.

Personally, I'd focus on the hull first, but that's just me. Whatever you can do to stay motivated, man.

I think a compression test would be more thorough, but I always like the "gut checks" to ensure that it makes sense to keep working.

And I also agree about the hull first, it is in pretty decent shape thankfully. Some scuffs, but no dings or spiders. My goal was to start on the engine to see if I want to pull it out and rebuild, or clean it up, test it, and drop it back in. Then I get to do the fun work of floor (hopefully not stringers, tbd), seats, and wiring.

 

[ACon977]

Since you have it turning over I would agree about getting it running. I suppose before trying to start it you could pull the valve covers just to see that the valves are all doing what they are supposed to.
Why pull the heads now?
I would do a compression test ONLY to see there is something in each cylinder and not even look at numbers until after it has run for a while under load and gotten good and warm.
If it starts, runs and idles decently what more do you want? It sounds like you want a boat to have fun with, you’re not going after a top performing race boat or heading 200 miles offshore for some fishing. There is a lot between a new fresh engine rebuilt to specs and one that is so worn that it will give chronic problems.
....sitting for a couple of years doesn’t necessarily mean anything. Those core plugs admittedly aren’t a good sign but you might be lucky.
Looks like a fun project.

Ned, I think you hit my mindset right on the head. I want an engine that runs consistently and has enough power to pull skiers, it is a ski boat afterall. but I can deal with a little lack of power or the engine not being perfect. If the performance is rough enough then I put it back in the shop and do the rebuild that I will probably do at some point anyways.

I pulled the valve covers off last night (I was mistakenly calling them the heads before, sorry!) and the risers were following the cam shaft well as i rotated the engine, there was even oil on the top of the lifters! seemed like a good sign to me.

After manually turning it for a bit I tried hooking up a battery and jumping the starter to see if it would turn over. AAAAND nothing.The battery in the boat is most likely junk, I was only able to charge it to 7-8V. but the solenoid didnt fire, and the starter didn't even try. I figured even at a low voltage it would still attempt to turn or hum or something. Does the solenoid only fire at 12V? or should I look for a new solenoid and starter? I will have to get a new battery regardless, but dont want to burn up a new battery on a busted starter.

 

[jbuote]

Not a pro here, but I can tell you that a battery at 7-8 Volts is a dead battery and won't do a thing...
I'd get a new battery first, or at least test with a different battery.. Borrow from car if you have to..
Might be able to fully charge existing one then have it load tested at local parts store, but I wouldn't count on it being that low..

In any event, don't go buying a solenoid or starter until you can test with a known good battery..

My $0.02