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27' Uniflite w/ twin 318's.......questions

Akjohn

Contributing Member
New member here with questions.
I recently aquired a 27' Uniflite Express Cruiser with twin 318's and Paragon transmisions.
The boat is not in my possesion as of yet, however it has been sitting for 8-9 years and I have been told the motors willl need to be replaced or rebuilt and I am trying to learn and decide the best course of action.
When I get the boat I can evaluate the condition of the motors, trannies, shafts and all that.

In the meantime I hope to learn what to look for and what might be the best route, I have made the assumption that if the trannies are still uasble replacing the 318's would be the simplest way to go.......?
Is this a reasonable course of action? Is it likely I can rebuild these motors or should I anticipate replacing?

Finally, do I really need 450 HP, yeah, I know that will be fun, but what about a couple of GM 4.3's.......?

Thanks.........John
 
First off, I'd never suggest re-building a previously salt water cooled engine.... if that's the case.
You're only a few dollars away from good automotive cores.

John, if the Paragon transmissons are Borg Warner pattern, just about any V-8 that is Borg Warner F/C capable can be made to fit.

You mentioned in another thread... "exhaust manifold replacement".
You can probably build a pair of SBC for less than what you could build the 318's for...., given that exhaust will be replaced anyway.

The rest is easy.
The B/W drive couplers should fit the SBC.
images


B/W flywheel covers are very easy to find.

HGE0100-000.jpg


Johnson crankshaft pumps are a no brainer.

JOP10242281.jpg



I think that you'd be dissappointed in the 4.3's, and the transmission ratio would not be correct.

Engine mounts would change, but those too should be easy to find.


.
 
Thanks Rick, good info, concerning the cooling, I wont know untill I get my hands on the boat in May/June. Same with the trannys. I dont know what was typical for Uniflites of that era......?

I suspect you say I will be disappointed in the 4.3 is due to the torque diffrence in the two motors? I was looking for some economy.........if thats possible.........? I was expecting 10GPH X 2 with the Mopar's.

Uniflite did offer that boat in a single screw, weighing 6500 pounds, twins setups were 7700Pounds, I have no clue how well the single performed but assumed (2) 4.3 would be lighter than (2) v-8's and still more power than a single.......?

As far as tranny ratio, can that be corrected with props or is that the wrong approach?

Lots to learn here...........!
 
Usually, a properly propped, larger engined boat, will get better gas mileage (at sensible cruise speed) than the same rig with smaller engines. That said, the 4.3s are both smaller in dislacement and a bit lighter so, in off plane cruise mode (if you do a lot of that), they would be more economical.

Your boat was built for the 318s, however, so it will cost you a ton of $ to convert them to the V-6s. And, since rebuilt 318s are cheaper than SB Chevies, replacing the 318s is you cheapest option.

Jeff
 
John, Jeff makes a good point about power. There are only two efficient speeds to operate at.
Hull Speed...... and Planing Speed.... and the planing speed should be a tad bit above what it takes to get on top of the water!
Smaller engines would do this.... so fuel costs generally end up being greater!

BTW... GPH does not indicate fuel economy since distance traveled is not part of the formula.
MPG is a more accurate means.

********************

Jeff, I see that we have a different opinion on the 318 -vs- the SBC 5.7L cost..... and you may be correct! Have to research this.

But let's say for the moment that the SBC engine is actually less expensive, or perhaps no more expensive.
If John is replacing exhaust manifolds X's 2 engines, and is over-hauling or rebuilding w/ fresh 318 cores, I don't see the SBC conversion as being all that much more costly.
If I'm correct in my previous post, he can aquire two fresh SBC at a lessor cost than two fresh 318's.


New starter motors and alternators either way.
New exhaust either way.
Drive couplers should interchange.
Paragon's either way, but the F/C's will change to Chevy pattern.

Engine mounts I believe will need to be changed, or at least a portion of them.
New ignition distributors will be required. ($600 tops)
New fuel pumps.
Carburetors may work on the SBC's... don't know what he has now.

MM offers a re-man'd 1987-95 5.7L in Long Block form, LH Std Rotation for $2,100.
You'd need to add a bit for the Stbd side RH Reverse Rotation engine.

Here's a pair of Neptune Marine over-hauled 318's complete and w/ transmissions. No price, so perhaps you need to call for price.
They've also got those Goofy Exhaust manifolds.... but..........

Just tossing this in the mix.
Jeff may very well be right, but I'd at least explore the two avenues.
 
I've done two complete repowers and both involved SBCs. Those engines, even though the basic design is now almost 60 years old, are one of the best engines ever made and in a more advanced form, are still in use today.

But to the poster's question, I wouldn't get involved with trying to replace the 318s with small block GM engines (even though the Paragon reverse gear and reduction unit will bolt up). There are just too many issues and besides, the 318 is a fine engine, as well, and long blocks aren't that expensive.

First, he has two donor engines that (hopefully) have all the brackets and other tin pieces that he can use to build up the new 318 long blocks. That includes pulleys that are the right size and bolt pattern for the 318. His old engines also have raw water pumps that will have to be rebuilt but at least he has them. This isn't a trivial issue when you're looking at an engine on a stand in your garage and trying to figure out how you are going to mount an alternator or other accessory and you don't have the right bracket to do it.

Sure, there are some issues with repowering with 318s. The intake manifolds probably can't be reused if the old engines were raw salt water cooled, but you can buy aftermarket manifolds that will work. The starters and alternators will have to be rebuilt as will the carbs. The entire exhaust system will have to replaced. The motor mounts will have to changed but those too are available. The ignition system would probably have to be upgraded too.

Then there's the boat-to-engine wiring harness. I don't remember how Uniflite did it, but I'd much rather use the 318 donor engines' wiring harnesses that will plug into the ones in his boat than I would to try and make up wiring harnesses for small block GM engines and then adapt them somehow to the boat wiring.

Finally, those Paragon gears that he has now will work with his rebuilt 318s without worrying about changing the reduction ratio, shaft size or prop specs. While the poster probably doesn't really care, when he's finished, he'll have a Uniflite that is powered as it was originally deigned from the factory.

I'll admit that I'm no Chrysler engine expert having just finished only my third season with 360s in my Silverton. I've only ever been on one Uniflite (a 34 ft late 1970s that I rewired after a cabin fire) but those boat have quite a following even today and are probably worth saving.

Whatever he does, it's an interesting - and fairly expensive - project.

Bill
 
Thanks guys, lots of food for thought here, which is what I was hoping for.

The price of the boat as it sits is cheap enough, I have agreed to pay $2500.00, sight unseen except for some pics, the boat shows wear and age as expected, I have been assured the hull is sound and believe this boat was built prior to Uniflites "Blister" issue.

There are a lot of things I do like about the boat, still its ~40 years old and when all these upgrades are completed I suspect I will have more invested than the boat is worth, and I realize this is often the case. Is it worth it? depends on how much time one has and how much they like the boat and are willing to spend. I have limited time to work on it and realsistically use it, my hopes are in the next 5 years to have more time available...............dont we all.......!

It appears that I may be better off continuing to save and buy a functioning boat that beeds minor upgrades or buy one that someone else has already upgraded, if one can qualify that work.

Rick, Jeff and Bill, what do you suspect this project would run? Assuming I do 80% of the work myself. I have a well set up shop big enough to get this in on ocasion. I can remove, install, assemble motors, rebuild systems, pumps as needed, I am Ok with rewiring as needed. I know costs can vary, as I have limited time to work on the boat I am not in a hurry and can devote some effort to "shopping" for parts at a reasonable cost. I am just looking for a rough guess, I have spent many a hour working on my riverboat and I know things cost and can get out of hand in a hurry, there is always "something" else that is needed or would be nice to have.

Thanks guys, John
 
Bill, the suggestion of the GM V-8 was a take-off from John's comment regarding the 4.3's. Had he not mentioned that, I'd have not suggested the 5.7's. I still think that it's a good option given that other items require replacement anyway.

John, at this point there are too many unknowns and perhaps your level of engine building experience would help here.

1... were the 318's previously salt water engines?
2... were the 318's open cooling systems? (raw water cooled)
3... are you capable of a complete 318 over-haul assembly.... baring machine work.
4... is the stbd engine a RH Reverse Rotation?
 
Rick,
Unfortunaely I cannot answer most of those questions at this time, The current owner has never actually used the boat so has limited knowledege and the boat is literally buried in Snow in Valdez AK, they have recieved over 27' of snow so far this season. Fortunately the snow is getting shoveled off of the boat.

I was hoping some one with Uniflite knowledge would chime in here concerning if it was raw water or fresh water cooled. I have contacted a few other Uniflite owners and may be able to find out what was typical, a response may take several days, but I will see what I can find out. Same with engine rotation.........

I wish I knew more...........getting a education now.........Thanks
Yes, I have the means to go through the motor and a good local machine shop.
 
Palin-ville! That makes shipment of long blocks MUCH more expensive (along with anything else you'' need to 'import' from the lower 48).

That local machine shop is looking better!

Jeff
 
John, if you mentioned Valdez AK prior to your last post, I missed it.
For me, and if (key word IF ) these were raw "salt" water cooled engines, I'd strongly encourage NOT over-hauling these blocks and cylinder heads.
I dont' care how well these can be baked or hot tanked, there will be severe corrosion within them that has compromized integrity.
This may mean shipping no matter which way you go, unless you have an engine core supplier in your area.

If they've been closed system cooled, then that's a different story.

.
 
Rick,
I did not mention AK before, so yes shipping is a part of the equation, however its done every day and there is some fairly good rescources in AK. But it certainly is not like the lower 48 as far as accessablity to used and new parts.

To the best of my knowledge these were raw water cooled and the STB engine is reverse roatation.
(I spoke to another 27 Uniflite owner last night, while this may not be definitive info, its what I have to assume at this point)
So is this (best guess) a 20K project or given enough time to scource economical parts can it be done for less?

In my mind the list of what may be useable is much shorter than what needs to be replaced. I assume I will be able to use the tin off the existing (if I stay w/ the 318's), and hopefully the trannies are still sound. I assume I will need new long blocks, in & ex manifolds, exhaust system (not sure what that entails yet), starters, alternators, pumps, heat exchangers, ignition and carbs...I assume 40 year old boat carbs are the same as 40 year old auto carbs and worn out in the throttle shaft area..............?

I know there will be tons of other items on the boat, but for know I am mostly concerned what this repower will (could) cost......

John
 
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John..Only one guy to talk to..Dave at Hurrikane.com, thats the right spelling, he'll be able to tell you what you need to know
 
Thanks Pete,
I sent him a pm but it has been awhile since he has posted here, and I did not locate him via google, so if you know how to contact him please pm me.

I have been doing some research and the only economical solution I see is to find a pair of complete running, marine 318's that I can swap out.
The other option is to power with some used Outboards, maybe twin 150's or 200's, some advantages here as I gain a lot of room under the floor for fuel tanks or a fish hold or freezer.

This could be a spendy route as well, I know the brackets are 3-4K, reinforce and or repair the transom, shop for used OB/s, rerig the whole shooting match............Any thoughts......?


John..Only one guy to talk to..Dave at Hurrikane.com, thats the right spelling, he'll be able to tell you what you need to know
 
John,

I own a 73 uniflite 31 sport sedan, my engines are*318's and have*closed cooling with thestarboard being the counter rotator. I also have pargon transmissions and vdrives which have an external oil coolers that are raw water cooled, you needto watch out as older paragons had water jackets instead of the oil coolers andI have heard many stories of them rotting out. What year is your Uniflite? Theyare wonderful boats if they have been taken care of properly, anything below1974 should be a pre blister uniflite and I believe the blisters mainly occurredin the boats in the*warmer climates. You can try uniflite world for more info onyour specific model but the activity there has almost died off since they triedswitching to a Facebook only forum(try both the face book and google grouppages) and then re-opened the google groups page in an effort to save theforum. If you have something close to a 73 I have some price guides at homethat list some of the original equipment on most of the 73 models which you mayfind useful. I do not see you spending even close to 20k for a repower with 318's. The exhuast componets are pricey though, I want to say I spent around 800 to 900$ per engine for manifolds, risers and elbows.*You can search previous post on the forum and you may fins some pricing on rebuilt 318's.*

Best of luck,

Matt

 
Hi John,

You've had a lot of replies to your questions and Mattv actually owns a Uniflite so his opinion really counts!

I've done two major old-boat rehabs and the first turned out okay (sold the boat) and the second one so good that I kept the boat for eight years. I repowered both boats (Chris Craft 305Qs to home made GM 350Qs) and Chris-Craft 327s to home made GM 350s. The second boat's repower, with rebuilt long blocks, cost about $4,000 with me doing all of the work myself. With the rebuilt engines in, I then replaced the entire electrical system: every wire in the boat came out and was replaced. That cost about $1,000 and took two winters again, with me doing all the work.

After that, I used and really enjoyed the boat each season and during that time continued to fixing things when they stopped working: control cables; steering system; stuffing boxes; battery charger; new carbs; bilge pumps; old electronics; starters; alternators; gauges and eventually, a second set of exhaust manifolds and risers. It seemed (and I'm not complaining) that I was constantly reaching into my pocket to buy/fix something else. I would say that in the eight years I had that boat after repowering it, I spent another $10,000 - $12,000 to keep it going safely.

Of course, I love old boats and it's a hobby for me to work on them, so no complaints. I'm doing lots of these things again on another old boat, this time a Silverton.

I guess my point is that when boats are old, they will need constant maintenance and repair and no matter how handy you are, that does cost money.

Good luck with your Uniflite! They were nice boats.

Bill
 
Thanks again everyone for all the information, I dont have 20K to throw at this project and I hope I can get it done for roughly 1/2 of that, at least the repower. I know there will be plenty of other expenses and ongoing maintenance costs. I am not entirely new to boats. I have been mucking around with a jet powered riverboat for the last 6 years and there is always something need, and its a 2007.........!

The world of old fiberglass v-8, stern drives (if thats the right term) is new to me, I am confident I have the skills and knwoledge to perform 75% of the work needed, maybe more time permitting.

Ir seems there are 3 most likely options that are reasonable, twin OB's, R&R the 318's or go GM. Logically staying with 318's should be the least expensive and simplest, assuming the paragons are useable. I really need to try to pin down the cost of replacing, I have found 3 sets of complete running 318's, one set is on this forum listed for 5K with BW Velvet drives plus another 1K for shipping, this doesnt sound like a bad deal if I can qualify the motors. heres the listing.......... http://www.marineengine.com/boat-cl...hrysler318-2f240-hp-with-1-5-ratio-gears.html

Anyone familar with this outfit? and can I use the BW velvet drives?

Buying used from some one I dont know that is on the other side of the country is cause for concern, unlike a modern OB you cant plug it into the computer to find out how amy hours are on the motors. Maybe even if I have planned on rebuilding, they would provide plenty of donor parts.............I suspect the manifolds and exhaust system could still be questionable, Is that something that can be inspected?

The next course is to start with long blocks and start adding parts, I have looked some but not sure who to go to for that, any suggestions?

I did try to call Dave with Hurrikane and he is on the road, so will try again next week................

Thanks all.........John
 
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John,

Yes, you can use the Velvet drives although I believe the overall length of the Velet Drive is slightly longer than the Paragons you have on your old engines. If that turns out to be the case, you might have to shorten the prop shaft a bit to make them fit.

The Velvet drives in the ad have 1:1.5 reduction gears. Many Paragons had a similar gearset (1:1.51, I think). If your old Paragons are the same, you'd be able to get away without re-propping.

Bill
 
John,

I have followed this tread with interest, and have had boats own me for a far back as I can remember. If you are in the market for a Uniflite, why not pick up a fully operational one?

They do seem to sit on the market for quite some time, and are modestly priced, most of them are about in the ballpark you have in mind for your engine situation alone.
 
That certainly has entered my mind and at first consideration it makes alot of sense, I even spent some effort looking in the lower 48, and I found several for around 15K. They were sold and the one owner really liked his 27'. I could continue to shop to look, but the real reason is the logistics involved with buying a boat some 2400-5000 miles away.

If I was shopping for a 50K boat and could buy one for 30K in the lower 48, it might make sense, but not for a 15K boat, at least the way I see it. Finding the boat is just a matter of looking long enough. Once I found a likely cnaidate I would really consider getting it surveyed & determining if its worthwhile, as its a expensive proposistion just to go & look. Once a decsion and agreement is reached I have to go get it. Its a 2400 mile one way trip to Seattle and I am estimating it would cost 3-4K just to go get the boat if its on the west coast. Its a long way to tow a heavy boat, a 40 year old boat and most likely a 40 year old trailer. So I would have to anticipate spending some money on the trailer or I could have it put on the Ferry and delivered to Haines as thats only a 1200 mile round trip.

It just doesnt seem that spending 4K to retrieve a 15K boat is a good decsion.............? But then most boat decsions are in that category....LOL


So far the seller has been busy dealing with all the snow in Valdez and working and I may not even get this boat in my yard untill mid-June......


John,

I have followed this tread with interest, and have had boats own me for a far back as I can remember. If you are in the market for a Uniflite, why not pick up a fully operational one?

They do seem to sit on the market for quite some time, and are modestly priced, most of them are about in the ballpark you have in mind for your engine situation alone.
 
Hi John,

I know I am late to the party here but I wanted to say welcome to the forum. I have a 73 Uniflite 31 Sport Sedan. It is my first power boat (I have owned a number of sail boats and have sailed my entire life though, in fact I still have a sailboat I race). It has the 318's a paragon gears as well. My boat also needed work when I got her last April. I redid the upper and lower exhaust elbows, but did not replace the manifolds, instead opted to scrape them out as best I could (total cost $2,500 in parts). My boat is fresh water cooled, but I can tell you it will be almost impossible that the exhaust won't need to be replaced (and the elbows can not be boiled out because of the design). I also replaced the carter carbs with new edelbrocks ($1,000), and replaced the coils and added electronic ignition (pertronix, $250). The result is a pair of fine motors that run well.

Anyway, congrats on your purchase and let me know if you have any questions I can answer. Thanks!
 
318s Make sure you have these parts before you go on with the long blocks....the right oil pan,intake manifold,timing cover,different parts for counterrotator,the right valve covers....they are not included in my estimate below!!



Better put 5,000-6000 away for bolt on parts for both motors,go ahead and make nice strong motor mounts if those are iffy,get your rebuilt long blocks for 1500 a piece
9k is the tally go ahead and make that 10k to get it to you.If you go thru the trannies(rebuild yourself) add another 750 parts say 250 for hardware,wirings hoses,belts,odd ball pulleys,where we at 11k ,most likey good idea to look at that fuel tank throw out another grand right there start fresh 12k

what else what else???

oh, anything in the running gear below the boat needs to be replace 250 per item

Throw in a nice gps/2 or 3 batteries,decent charging system, with about 2-3 months of your time maybe??gettin on it pretty good when you can I think you'll just break it under 15,000 with your labor and whoever you can coax into helping!!

Like to see you do it
 
Thanks for all the input, some recent developments. Yestreday I bought two 360's with trannies. They were in Anchorage and I should have them on monday.

It was a CL ad and said "I have for sale two very large Chrysler motors that came out of a boat a family member bought with out thinking"......

Are you kidding, I couldnt ignore this, there was very little usefull info in the ad. But I spoke to the seller and apparently his uncle bought this boat, removed the motors to make repairs to the hull, had the boat in storage, didnt pay the storage fees, lost the boat to the storage yard and the nephew ended up with the motors in his warehouse and has now sold them to me............Can you believe this, I could not make this stuff up..........

I paid $600.00 for the pair, it is a roll of the dice..............the motors were running when they came out of the boat, they look complete, and have been in storage for about a year.........

The seller could not provide any more inof than that, I can see Chrysler Marine 250 on a plastic? cover on what I believe is part of the heat exchanger, it does have the exhaust manifolds & risers and I can see what looks like a trannie, the trannie does not appear to be a V-drive so they may be a bonus over the Paragons in the Uniflite.........

I tried to find out more info on the 360's.....? I know Chrysler made 360 marine motors from 71 - 88, if I remember correctly, I presume they will fit.......?

The plan when I get them is to remove the plugs, squirt some oil in the cyclinders and see if they turn over? If so I will let them set until I can get time to try and fire them up. If they run ok and the compression checks out I plan to drop them in the boat.......After I do some more inspecting, I probably need to clean the heat excahnger, check the raw water pump, new gaskets.........that will get done

The boat is still in Valdez, I hope to get the boat back to Fairbanks in April but it may not happen until end of June...

This is a budget project, for now, I want to make sure I like it, I wont put it on the water until I know its solid but 2 motors for 600 bucks..........
I couldnt pass that up.

John
 
"31' or 33' w/ swim platform
1974 Uniflite Sedan Cruiser Loaded"

Greasemonkey, I think it's just one boat.

Those hulls are interesting, the same design as the Navy PBR's.
 
Reverend,
I think Grease Monkey meant buy the 31 footer in Seward, which comes with a pair of complete 318's and then with the 27 footer I have, end up with two boats..........not sure where the 8 motors came in, YIKES....! things are really getting outa hand....!
Neat idea, but way too ambitious for me.....

I did in fact talk to the seller of the 31 a while back, it has been for sale all winter and at one point they were asking 20K, looks like a nice boat and sounds like a fair deal to me.......but too much boat for me at this time. I asked if they wanted to sell off the motors seperately and they sounded interested, but have never got back to me so I moved on...

I am concerned the 27 footer is too much boat when I go to tow it with my F250.....!

What do you guys think about the 360's in place of the 318's.............?
 
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