OMC 5.8 EFI and Cobra SX drive

[p8nt]

I have this power setup on my 95 Four Winns Vista 258. Runs fantastic, nothing wrong at the moment.

However I've come to understand a few key parts are NLA on the Ford engine and I'm curious about what options I may have should something go bad. I'm new to the forum and have done my best to search, so I apologize if this has been covered.

Being that this drive is a OMC/Volvo joint venture, would there be Volvo engine of a similar vintage that could bolt up to this out drive and engine mounts?

Are the Cobra SX and Volvo SX identical, or just similar?

As I say, Im just trying to prepare for the inevitable. Thanks in advance!

 

[Scott Danforth]

all the fuel injection parts are NLA

if the FI parts die, you can either find used, or you can convert the engine to carburated.....as far as other motors, you can find a complete GM based motor and swap everything forward of the transom

parts are available from volvo if the drive is a full-blown SX with OMC stickers

 

[Lou C]

Some parts for sure are NLA, Volvo may still stock them but they have a fair number of parts that are NLA also...the carbed engine is an option....they used Holleys when they used these engines with carbs...the drive parts...all should be as available as they are for the same year Volvo SX....

 

[p8nt]

Thanks for the quick replies, glad I found active forum!

OK so I can carb the engine I've got, good to know.

Also, am I reading correctly that any GM based motor (Volvo branded I'm guessing) will just drop in and use my current drive? That seems to good to be true.

Specifically regarding the joint venture drives. Are the OMC and Volvo branded drives IDENTICAL (apart from branding) in parts, or do they simply share SOME common parts?

Thank again, the advice is really appreciated!

 

[Lou C]

I believe the drives are identical. The switch from a FoMoCo engine to GM is not quite that simple...there are other differences...the engine mounts...the bell housing...inner transom plate...the exhaust Y pipe...and the rest of the exhaust system are all different. I bet most of those parts are NLA...but they are no doubt out there used.... If it were me as long as I could get exhaust manifolds and elbows (here in the salt we change em every 5-7 seasons)...I'd keep the Ford, as long as its in good shape. Re-man Ford marine engines are still available. The only other stumbling block would be the electronic ignition, if the module is NLA....what then...unless Mallory or someone makes a marine dist for the small block Ford still....

 

[p8nt]

Good call on the Mallory distributor - https://www.cpperformance.com/p-141...type-distributors-351w-ford-single-point.aspx

What about a manifold for converting to card? I’m not a ford guy, would a manifold off of a carbed 5.0 fit a 351w?

 

[Scott Danforth]

dont get the point distributor, get the electronic one if you are going to switch

Mallory is also now sold under the Sierra name (for about double they were being sold for prior)

 

[HT32BSX115]

there are other differences...the engine mounts...the bell housing...inner transom plate...the exhaust Y pipe...and the rest of the exhaust system are all different. I bet most of those parts are NLA...but they are no doubt out there used....

That's right!

After I removed all my OMG 460 King Kobra stuff from my 87 FourWinns 211LIB, I started trying to sell it all piece by piece.......

One guy in TX had his Y-pipe corrode so badly, that it nearly sunk (sank?) the boat! His only option was to switch to Thru-Hull exhaust if he couldn't find a Y-pipe (and he couldn't find one until he saw mine for sale)

Another guy in Cal had a coupler literally "blow-up" in his big Bayliner and it damaged (beyond repair) the 460 bell housing, inner plate and transom mount. He could not find one (anywhere nation wide unless he bought a boat with a 460 installed) and his insurance company had already decided to "total" the boat because there was no fix for it until I told him I had a good condition bell housing + transom mount for a 460.

I sold my old points type distributor and engine harness to a guy locally that had a Spit-Fire ignition system on his 90 460 King Cobra. (his was the "nightmare" ignition system and "nightmare" Interim OMC Cone clutch drive)

As I say, Im just trying to prepare for the inevitable. Thanks in advance!

Your best bet is to obtain a distributor and carburetor if (when) the time comes. You'll probably still have years of service parts available for the 5.8L FOMOCO engine as long as you don't break any of the (showstopper) hard parts.

I would be looking for the stuff to swap out the Ford engine and go to a GM 350 or 454 in a boat that big.......and in reality, I would want a Duo-Prop drive on it too!


If your boat has not been modified in the last 26 yrs, It might be useful to compare your model number to other models and look up parts numbers.

You can go to http://epc.brp.com/ and look up what you have. (btw It's possible for 1995 model year boats to have 94 model engines and drives If yours has an engine mounted raw water pump and it's EFI, it's should be a 95. The model number tells for sure)

Here's similar models for your year and 1 year earlier from : http://epc.brp.com/

584ACPMDA 1994
584AGPMDA 1994
58FACPMDA 1994
58FACPMDM 1994
58FAGPMDA 1994
58FAGPMDM 1994

58FBDPMDA 1994

Carbureted:
584APHUB 1995
584APHUE 1995

EFI: ( Yours should be one of these)
58FAPHUB 1995
58FAPHUE 1995
58FBPHUB 1995
58FBPHUE 1995


I noticed that the Y-pipe for example, is the same part number in 1996 for the 5.7L and 5.8L engines (but NOT the same for 94/95)

96 appears to be the last year for the Ford 5.0/5.8L engines.......the 5.0L in 1998 is a GM engine (dist behind the intake manifold)

The whole point of all this is that, by knowing your model number, you can look at other years close to yours and see which ones have identical part numbers, or see which part numbers you might need to do a swap etc.


I was really "stuck" with my 460. At the time, (new) exhaust manifolds and couplers were not available from anyone at any price. There were a few "New, Old Stock" manifolds available sitting on shelves across the country......Doug Russel for example wanted $1600 (each) for manifolds. A couple was nowhere to be found except for used. (I understand Sierra now does have couplers)

I lucked out finding the Mercruiser eng/drive used locally!

Good luck!


Rick

 

[p8nt]

That's right!

After I removed all my OMG 460 King Kobra stuff from my 87 FourWinns 211LIB, I started trying to sell it all piece by piece.......

One guy in TX had his Y-pipe corrode so badly, that it nearly sunk (sank?) the boat! His only option was to switch to Thru-Hull exhaust if he couldn't find a Y-pipe (and he couldn't find one until he saw mine for sale)

Another guy in Cal had a coupler literally "blow-up" in his big Bayliner and it damaged (beyond repair) the 460 bell housing, inner plate and transom mount. He could not find one (anywhere nation wide unless he bought a boat with a 460 installed) and his insurance company had already decided to "total" the boat because there was no fix for it until I told him I had a good condition bell housing + transom mount for a 460.

I sold my old points type distributor and engine harness to a guy locally that had a Spit-Fire ignition system on his 90 460 King Cobra. (his was the "nightmare" ignition system and "nightmare" Interim OMC Cone clutch drive)

Good point, thanks for the input Rick. To be honest, the reason I'm considering doing this BEFORE something breaks is that currently I have hard to find parts in perfect working order. Selling the NLA parts I have could offset some cost in swapping. Just a quick ebay browse turned up the inner transom plate and bellhousing I would need for a Volvo/GM based swap for dirt cheap.

Same with my SX outdrive. Sell what I've got after I locate an upper and lowers off a SX DP drive.

Here's the numbers I've come up with so far.

From the engine tag:
Engine - 58FAPHUB
Transom Assembly - 3868175
Outdrive - 3868158

Hull - FWNCS2090495

Thanks again for all the input everybody, I appreciate the education!

 

[HT32BSX115]

Same with my SX outdrive. Sell what I've got after I locate an upper and lowers off a SX DP drive.

If you're truly thinking about going to a VP DUO-PROP (or even a Mercruiser Bravo III) drive on your FW 258, I can tell you right now that switching to a similarly powered engine or even a 6.2L or 383 small block GM engine, you would see a spectacular improvement in performance.

If you found a complete package (like I did) the swap wouldn't be all that hard. I had no problem pulling out the OMG 460/King Kobra and installing the newer '97 7.4L + Bravo III package.

The performance difference was awesome...the 460 I had was similar in HP to the 454. The single prop Cobra was slow" out of the hole but fairly fast top speed. (about 60mph)

With the Bravo III. It comes out of the hole like a ski-boat and I'm only 3-5 mph slower (big deal)

I looked all over the PNW for a (SBC/BBC)300+ hp Duo-Prop VP package but never found one.

I did find a LOT of Mercruiser packages and and right after I bought the complete 1997 7.4L+ Bravo III set up, I found a newer (2000s) 425hp 496/Bravo III package for about $3500 more!

I now wish I had bought it. I could have nearly doubled my money selling the 454/B3 package!!

If you REALLY like your boat, it's in good shape (no rot etc) and you can do the swap yourself on your time line, it's worth doing this kind of swap.

If you can't do it yourself, it won't be worth it and you would probably be better off just selling everything in it's current shape while it's running good and finding something newer with the engine and power you want!

Buy boats in the fall right after Summer and before winterization so you can test-fly it.......and sell your boat in the Spring right after DE-winterization when people are hot to buy a boat for the Summer!!




Good luck!

Rick

 

[p8nt]

quick update:

I've found a new ecm for <500, and a used distributor 130ish. Exhaust parts seems to show up on fleebay with regularity.

I also found locally a Volvo 5.7 GL with 530 hours from a 1997 Sundowner 230. This engine is a complete drop-in, and both boats used the same inner transom mount.

I see this being our boat for the next few years at least. From the perspective of preserving resale value, Is my money better spent accumulating NLA parts, or putting those same dollars towards swapping for a more serviceable engine?

 

[Scott Danforth]

most people wont touch a Ford motor in a boat no mater how many parts you have

for resale, get something that most people can get parts for

 

[HT32BSX115]

quick update:

I've found a new ecm for <500, and a used distributor 130ish. Exhaust parts seems to show up on fleebay with regularity.

I also found locally a Volvo 5.7 GL with 530 hours from a 1997 Sundowner 230. This engine is a complete drop-in, and both boats used the same inner transom mount.

I see this being our boat for the next few years at least. From the perspective of preserving resale value, Is my money better spent accumulating NLA parts, or putting those same dollars towards swapping for a more serviceable engine?

I wouldn't waste any money trying to fix the EFI if it breaks. Just put a carburetor and marine dist on it and keep boating.

If you can buy a good condx 5.7 (GM) engine) with manifolds and risers and other accys, I would go for it! Once you're switched to a GM engine, with the SX drive, you'll have decent resale (compared to Ford powered) when the time comes!

And you could probably part out that 5.8 engine and EFI stuff if it all works. There's a LOT of people out there with broke EFI systems that can't find any parts for them.....

 

[Lou C]

Agreed once you go to a GM engine with the SX drive set up you will have easier parts availability and resale. And you can eventually convert your SX to an SX/DP by exchanging the lower units when funds allow. For my old boat that's what I plan to do when the Cobra drive acts up, remove the pivot housing and convert it to an SX drive set up. I already have the Volvo Penta style exhaust manifolds and elbows on it. The original OMC Cobra standard dog clutch models can be converted to an SX by exchanging the OMC pivot housing for the V/P one (slightly longer) and making a few other changes (crank mounted water pump, etc). You don't need to change the rest of the original OMC transom mount and steering assembly, that all can stay if its in good shape.

However if your Ford engine is in good shape now, not causing trouble....I'd run it as is....if the EFI acts up, Holley still sells the OE carb that was used on these engines. Reman Ford marine engines are out there, but you'd have to find out can you get other parts that might need replacement in the future (ie exhaust manifolds and elbows and couplers). I think manifolds and elbows are out there....check Barr marine....

 

[p8nt]

Thanks for the feedback guys, much appreciated.

A bit unrelated: any idea what this engine should be idling at? Pretty sure my tach is off and I’m trying to calibrate it.

 

[Scott Danforth]

get a good shop tach and see what your engine is idling at. then get your dash tach to match. I use a laser tach.

 

[p8nt]

And you can eventually convert your SX to an SX/DP by exchanging the lower units when funds allow.

Thanks Lou, this is something I've been eyeing as well.

Is it really as simple as swapping (with the correct gear ratio of course) the lower unit? Aren't there different iterations of the SX drive? C1, etc? Curious if certain SX/DP lower units will only work with certain SX drive versions.

 

[p8nt]

get a good shop tach and see what your engine is idling at. then get your dash tach to match. I use a laser tach.

Thanks, that's where I'll start.