1988 Imperial 280sf engine swap and restoration (pics)

[zool]

Launch Day, The final frontier: These are the voyages of the restoration of the sportfish Enterprise. The 2 year mission to explore strange new crevices, seek out rot and rubbish, to boldly go where many here have gone......

ok so, short history, ive owned the boat since the mid 90,s but its been drydocked for like 8 years after the pulpit hung under the bulkhead during a storm. Also, the motors, though relatively low in hours, are rusting out due to the PO cutting the drip edge of the engine hatches to allow room for the flame arrestors since the bonehead wanted to remove the cross brace out of lazyness i guess, ive struggled with it since, especially with these interference motors ....more on that later as its one of the repairs needed to be figured out.

Plan is to replace the twin 4 cyl volvo aq171c's with new twin GM 5.7l and shim up new lower units on the existing 290 drives. Check for bad wood in the engine compartment, and prep it for the new power. Repair the pulpit damage and the engine hatch butchery, renovated entire interior, in and out, shoot the entire boat with PPG Concept, and go over all other systems and fix whats needed. Needless to say, ill be here for a while

Anyway, ill try to update this as often as possible with plenty of pics, and am open to all advice, help, commentary, or any old BS....now lets see if the test pic i uploaded shows up....

 

[GWPSR]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Nice hull design. I'll be following.

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

all in all, its not in too bad shape, just needs like everything gone over......

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Welcome aboard...grab a beer...Im doing this basically alone, so cyber advice and or company is cool...

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Here's a pic of the hatchet job the PO did to the drain edge of the engine compartment.

I figure ill have to make a mold of the drip edge radius and glass it together. the water flows to a drain overboard port and starboard, at least that was how it was designed. Right now, it just drains over the engines if left uncoverd . The portions that are cut out are removable hatches.

 

[25thmustang]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Looks like a good project. Have you measured to confirm 350s will fit? Twin 4cyl equipped boats tend to have the motors mounted do close, that the outdrive holes may not work with v shaped engines. Hopefully you have the room and don't have to redo the transom for the twin v8s.

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Hey Mustang...

Yep, I measured 34" center to center. The boat has a 10' beam and i believe was available with the twin sbc option. The parts list for the conversion wasnt too bad, and ive got most of what I need.

I have the 161:1 lower gear ratios for the v8's, v8 y pipes, i still need the flywheel covers, and of course engines

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

I made up some quick cradles for the new lowers and a workstand for the shimming. I figured it was easier to reshim v8 lowers to my existing drives, as opposed to reshimming and lashing a new hypoid gear set in my original lowers. I also have a whole 280 v8 drive for parts if needed.

 

[25thmustang]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Glad to hear they should fit!

Nice stands as well.

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Thanks Mustang,

I was checking out your wood finishing and now I see im gonna be holding myself to a high standard, lol..nice work

Aside from rebuilding and refinishing the cabin entry bifolds, the interior is that 80's grey laminate over ply with the edges capped in plastic rubrail. Im planning to use some type of wood vaneer, then clearing over it for a full gloss, and capping it with wood molding.





Im not planning on taking the walls down to refinish, just the carpet and upholstery, doors off, ect.

What are your thoughts on laminating over the current grey laminate with the wood vaneer sheets..?

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Update:

I got a chance today to work on the boat today. All started out well, the sun was out, I drained the oil from the starboard drive and the oil was golden and clear!. The prop assembly came off with little effort, the steering pin came out as intended with the jacking screws, shift cover off no problem, the bellows I cut off cuz it needed it. The upper gear housing unbolted without a problem. Spent a good hour wrestling off the upper housing from the flywheel cover, but with a ton of wd40/crc/crowbar on wood blocking, it came out!



Task Complete!..well no, the thing about twins is just whem you're done...you're half way done...

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

So moving right along, the port side was next. I drained the oil and again, golden and realtively clear! The prop assembly came of without a hitch, started to remove the shift cover and the bottom screw head bolt just wouldnt budge. Sprayed with wd40, hammered screwdriver, heated with torch...nuthin. ok, ill get back to that.

Proceded to jack out steering pin with bolts from other drive and snap, both #8's broke off, this one looks like it hasnt been removed like ever.

So I drilled out the bolt and ran a 1/4-20 tap...and that snapped! Gonna try to make a spanner type tool for the mounting holes and wrestle it out, its just pressed in. Grr



If I can figure a way to attach the slidehammer to that stud with the nut i added, that might work too...the part is shot already.

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

I got most of the starboard engine disconected except the exhaust and the motor mounts which were sprayed with crc because im gun-shy of seized bolts now lol.

While i was working on that, i was figureing how I would get these engines out. I couldnt figure a way with the cherry picker cuz it dont swivel and has those big *** legs out front. The gunnel is 7' from the ground at its lowest point.

Then I figured I could build a gurny on pneumatic tires, cuz the boat is on blocks... but my partner Dilberrt seemed concerned at the idea.



That squashed that idea. I think it may be money well spent to try a local tower who has the boom to just lift these out and put on tires.

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Update: Ok, progress is being made....since I have rare full days to work on this, im finding that a stolen hour or so every day or so, goes a long way, especially for the pile of "little tasks" needed.

alot of whats been going on is dismantling, but to keep this project documented, ill post quick updates.

I got the PIA steering pin out, had to cut the center portion between the mounting holes and spin it with a crow bar...sacrificed the part, but it out.

A MAC inpact screwdriver made short work of the screw head bolt on the shift cover..this drive is salted shut.





Im gonna need some heat to get the head off..

So since the weather is warming up, im gonna start addressing the needed glass work, and reserve the summer for it all. The drives will go in the shop for rainy day work.

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

I started removing all the hardware off the hull, including a ton of old screw snaps that werent aligned originally and looked like crap when the canvas was removed. Got the aluminum rubrail off, and a bunch of other stuff. Way more screws than what will go back.

One of the 2 main repairs I need to make is the structural repairs to the pulpit. As I said, it hung under a bulkhead cap, when a spring line let loose at the dock in a storm. It appears to have originally broker "down".

The cap is attched to the hull bottom with screws into an approx 1x4 domensional wood strip running the length of the hull. Theres ccess to it at the damaged area thru the anchor locker. It will move up and down a good 3" under pressure, like a diving board.



Here you can see how it wraps the hull bottom, there was cauking that let loose, and damage to the rubrail and front flanks of the cap. If I remeber correctly, the marina just faired the cracked cap to keep out water, but was never structurally corrected.

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)



Heres a close up, i thought about tabbing it inside with a few layers of 1708 and fileting it outside to look like a molded pulpit, but im thinking it would be too rigid and ultimately ruin the new finish. I cant say that the factory would have done it if it was right, cuz they did lots of wrong......but im really not sure....you could stand on it before the damage.

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)



This is the access i have, when I remove the hatch, it should work ok....

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

I got a chance today to do some exploring below decks. There is a crawl space below the cockpit area which is easily accesable due to the raised flush deck. The forward area of the firewall wasnt glassed over, just the engine side, and where the coffin box buts the firewall bulkhead. there was gaps in the cloth wrap, with just resin. The stringers also have these wrap voids. The rear firewall bulkhead is scrap, as is the coffin box.



this is the coffin box, not the stringer, but the stringers have the same situation, plus theres some delamination where they were tabbed to the hull bottom. Ill get some more pics when I get a chance. At this point, im gonna take up the decking in pieces, remove the rear bulkhead, and slide the 150g tank out to see whats going on underneath it.

The cabin bulkhead has a bunghole plug with 2 atwood pumps...its dry down there with no access for water to come in from the rear, only thru an open cabin door from rain or a failed seacock.

At this point I think ill be ok, redoing all the wood from the cabin bulkhead back to the transom, along with scarfing new stringers.
So far the transom is solid, but ill take some skin off and make sure after the engines come out.
Its gonna be a fun summer

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

Update:

Ok, with a combination of heat, a large rubber hammer, and a crowbar with a block of wood, I got the port side upper housing off. Salt corrosion where the bolts go thru the intermediate was a real pain..





Next is the hinge pins...Im sure they'll be stuck too.

 

[zool]

Re: 1988 Imperial 280sf engine swap and restoration (pics)

I got the port engine stripped of its accessories to get around down there and make them easier to handle when removing. Also removed the fresh water pumping system, battery charging system, halon, blower vents, ect. The water heater is all rusted out on the bottom, and will be a mess to remove.

I got the cusion and backing wood off the seat mold, put it away to make templates. The Molded base is attached to a sliding rail with 10 corroded bolts. Most snapped, one still wont give.