Repower 496 HO Mag

[rightytighty]

Buddy hurt his 500 hour 496 HO Mag in a Lavey.

Believe to be “just a head gasket”

We’ve pulled the engine,

He LOVES the boat and has no desire to change. This boat needs to be “turn key” . We have other boats that are “play boats”.

As the engine is on the stand and looking at all of the hoses, coolers, fittings, injectors, wiring(just a maze of sruff), all of it 20 years old…even if we fix the current problem, i just have the feeling the engine is going to enter the stage of “what’s wring now”, that sucks with this style if boat.

So we are thinking re-power, complete.

Is there a mercruiser plug n play option, that is complete? Truly plug n play. I.e - a new engine that will communicate with existing wiring still in the boat. Teague is an option but dont want to go down the high HP rabbit hole of broken drives, upgraded fuel systems etc etc

Appreciate the help!

 

[JFMFG]

Buddy hurt his 500 hour 496 HO Mag in a Lavey.

Believe to be “just a head gasket”

We’ve pulled the engine,

He LOVES the boat and has no desire to change. This boat needs to be “turn key” . We have other boats that are “play boats”.

As the engine is on the stand and looking at all of the hoses, coolers, fittings, injectors, wiring(just a maze of sruff), all of it 20 years old…even if we fix the current problem, i just have the feeling the engine is going to enter the stage of “what’s wring now”, that sucks with this style if boat.

So we are thinking re-power, complete.

Is there a mercruiser plug n play option, that is complete? Truly plug n play. I.e - a new engine that will communicate with existing wiring still in the boat. Teague is an option but dont want to go down the high HP rabbit hole of broken drives, upgraded fuel systems etc etc

Appreciate the help!

I just bought a new long block from merc and swapped accessories. Me meaning I had a shop do it. I put a rod through the block at 400 hours.

 

[rightytighty]

I just bought a new long block from merc and swapped accessories. Me meaning I had a shop do it. I put a rod through the block at 400 hours.

Thats an option for sure.

And here’s #1. Others look normal

 

[Shlbyntro]

you can either long block it as stated above which is actually not a bad option. the merc 496 long blocks are made by Dart and are stronger than the original GM engines.

or the only drop in crate engine that is going to be available is mercs 8.2L emissions motor or a blue motor.

what ever you do, don't let anybody talk you into repowering with a small block of any kind. I don't care if the hp rating is the same, they are not equal no matter how much an engineer tells you it is.

 

[rightytighty]

you can either long block it as stated above which is actually not a bad option. the merc 496 long blocks are made by Dart and are stronger than the original GM engines.

or the only drop in crate engine that is going to be available is mercs 8.2L emissions motor or a blue motor.

what ever you do, don't let anybody talk you into repowering with a small block of any kind. I don't care if the hp rating is the same, they are not equal no matter how much an engineer tells you it is.

Will the 8.2 crate engine you mentioned above plug and play directly with existing wiring from 2002?

 

[Shlbyntro]

The 8.2 is a DTS motor so there would be some adapting. you will need new controls/harness for that and at a minimum there is an adapter box to convert the digital instrumentation signals to analog for your old gauges. or you can switch to smartcraft gauges or vesselview. but beyond that, it uses the same mounting holes in the boat and most the hookups will be in the same location. overall engine dimensions are near identical with the differences owing mostly to the catalytic converter exhaust manifolds

 

[Andy B.]

Crate motor from Merc and plug your injection in if you have other fast boats to run trust me!!!

 

[02HoWaRd26]

The 525 is always an option, there’s a few places back east that sell legitimate fresh rebuilds ready to drop in. And some may even accept his 496 as a trade in.

 

[JFMFG]

The 525 is always an option, there’s a few places back east that sell legitimate fresh rebuilds ready to drop in. And some may even accept his 496 as a trade in.

Prob 20k full investment.

 

[Andy B.]

Prob 20k full investment.

I wish I would have gone this route.

 

[JFMFG]

I wish I would have gone this route.

You’re telling me.

 

[rightytighty]

The 8.2 is a DTS motor so there would be some adapting. you will need new controls/harness for that and at a minimum there is an adapter box to convert the digital instrumentation signals to analog for your old gauges. or you can switch to smartcraft gauges or vesselview. but beyond that, it uses the same mounting holes in the boat and most the hookups will be in the same location. overall engine dimensions are near identical with the differences owing mostly to the catalytic converter exhaust manifolds

Ive noticed the mercruiser 540 . Its seems like its got a solid bottom end and rated at 465 HP. Its a complete engine but carbureted. I dont look at that as a bad thing. We boat at one lake so tuning is not an issue..

What do you think of that combo?

 

[rightytighty]

 

[Shlbyntro]

I like the engine. I don't think its a mystery to anyone here that I am a fan of carbureted engines. This engine would be much closer to a drop in replacement than the 8.2L. This engine will have a personality. IMO it has always been overpriced for what it is but if the price doesn't bother you, go for it!

 

[rightytighty]

I like the engine. I don't think its a mystery to anyone here that I am a fan of carbureted engines. This engine would be much closer to a drop in replacement than the 8.2L. This engine will have a personality. IMO it has always been overpriced for what it is but if the price doesn't bother you, go for it!

If my buddy wants to go the long block route (and switch existing hardware over), do you have a preference of builder/ supplier?

Thanks!

 

[Shlbyntro]

you are pretty limited in long block options on the 496. Merc is really the only dependable long blocker in that arena.

 

[chadzilla]

Couple things I would like to add here. First, unfortunately, the mercury 540 mag is no longer available. Not sure why but maybe price. In regards to price one must compare apples to apples. When you buy a long block from merc, it comes with a 1 year warranty. Second, depending on the model, it will come complete from the oil pan to the valve covers and some even come with the intake manifold. That is a big deal as most rebuilders only supply the base long block; not complete with oil pan, balancer, timing cover etc. Having to add all these parts costs time and if there is a leak, who is going to cover it? Third, the warranty. Nobody in the marine world has a better warranty than mercury. Period. If we install anything from mercury and it fails, all it takes is a few phone calls and a new part (sometimes a complete engine) will be on its' way. They will also pay us to r&r the part. I've dealt with almost every rebuilder in the country and now only offer mercury remans because of this. Mercury also periodically offers engines as CPO or certified pre-owned. They are complete engines and come with a standard 1 year warranty at a significantly discounted price. We just repowered a 1992 Formula 242 with a Mercury 8.2L mag DTS. Aside from having to convert everything to digital, the only issue we ran into was exhaust tip location. We had to make some tailpipes for it. Personally, I am a huge fan of DTS so long as the customer is educated on the system. Talk to your local mercury dealer and explore your options. Mercury also offers financing on the repower options so think about that as well.

 

[Shlbyntro]

Couple things I would like to add here. First, unfortunately, the mercury 540 mag is no longer available. Not sure why but maybe price. In regards to price one must compare apples to apples. When you buy a long block from merc, it comes with a 1 year warranty. Second, depending on the model, it will come complete from the oil pan to the valve covers and some even come with the intake manifold. That is a big deal as most rebuilders only supply the base long block; not complete with oil pan, balancer, timing cover etc. Having to add all these parts costs time and if there is a leak, who is going to cover it? Third, the warranty. Nobody in the marine world has a better warranty than mercury. Period. If we install anything from mercury and it fails, all it takes is a few phone calls and a new part (sometimes a complete engine) will be on its' way. They will also pay us to r&r the part. I've dealt with almost every rebuilder in the country and now only offer mercury remans because of this. Mercury also periodically offers engines as CPO or certified pre-owned. They are complete engines and come with a standard 1 year warranty at a significantly discounted price. We just repowered a 1992 Formula 242 with a Mercury 8.2L mag DTS. Aside from having to convert everything to digital, the only issue we ran into was exhaust tip location. We had to make some tailpipes for it. Personally, I am a huge fan of DTS so long as the customer is educated on the system. Talk to your local mercury dealer and explore your options. Mercury also offers financing on the repower options so think about that as well.

I personally am not a fan of DTS but I do believe that if they don't long block the boat then the 8.2DTS (even though I hate it) is the best crate engine for what they are looking to do with the boat

 

[Goodtime$]

DTS sucks for a REPOWER
It’s a complete new rig kit and the prices for up every quarter I feel.

Todd’s performance rebuilds the 496 metric block in lake havasu successfully. No one really makes upgrade parts for the 8.1
Psi makes the 8.8 but that’s another worm hole.

Most motor builders will do a nice carb to pan 540 bbc for $18k range Gen iv big block

There is a not a cheap 496ho REPOWER unfortunately yet. There is a market for it

1. Rebuild 496ho
2. Build a custom motor w Holley efi
3. Find a used hp525 and refresh
4. New Merc 8.2 Ho 502 is last on list for value in my eyes

 

[rightytighty]

So- just following up on this thread. I feel like we are getting super lucky.

My son’s friend (also a board member) found this low hour HO Mag on FB Marketplace. I heard it run and had a leak down performed in town lthis morning. (Thanks G!)

287 hours and 150+ are at idle.

Hopefully, it serves my buddy and his wife well.

 

[JFMFG]

View attachment 1283664 View attachment 1283665
So- just following up on this thread. I feel like we are getting super lucky.

My son’s friend (also a board member) found this low hour HO Mag on FB Marketplace. I heard it run and had a leak down performed in town lthis morning. (Thanks G!)

287 hours and 150+ are at idle.

Hopefully, it serves my buddy and his wife well.

Nice what did that set you back?

 

[rightytighty]

Nice what did that set you back?

$10 K

 

[JFMFG]

$10 K

Not bad

 

[yuppie]

My 496HO is coming close to 600hrs and I think I'll need to get it rebuilt a little later down the road. I've always thought of re-powering but it seems very incremental.

 

[rightytighty]

Not bad

I was stoked. More than 70% of the hours under 3K and very few over 4500 rpm

 

[HubbaHubbaLife]

Not much to add given My baby @Shlbyntro has spoken.... I've only been told these 496HOs especially one with such low idle rpm time run For-fucking-eva. Go forward in confidence. We have so much engine expertise on RDP and this aging engine model though being ugraded and surpassed still remains the Meat n Potatoes from its era.

 

[JFMFG]

I was stoked. More than 70% of the hours under 3K and very few over 4500 rpm

That’s badass.

 

[Singleton]

My 496HO is coming close to 600hrs and I think I'll need to get it rebuilt a little later down the road. I've always thought of re-powering but it seems very incremental.

I have driven the same boat I have with a 525 and 600. measurable differences, but huge cost differences.
If my 496HO decides it no longer wants to run (even with all the love it gets), I would be looking at the https://www.ilmor.com/Marine/High-Performance/Supercharged-650

 

[rightytighty]

Final update. Well- we did it! Had a little delay due to a surgery and general lack of winter motivation, but it is alive!

A couple of knuckle heads can switch out an engine (mostly), if you are partient.

While we had the outdrive out, we changed the gimble bearing, as well.

Had trouble aligning the engine after install. Took it to buddies mechanic in Rancho Cuc. He aligned and fired the engine. Start up video is from him.

Everything works, which is nice! Buddy Jeff took the boat to puddingstone and ran it around for an hour . All is back together now and ready for their annual mothers day trip to Pirates Cove.

 

[Ramjetfish]

Just curious where you went to in Rancho. Looking for a mechanic to re-align the gimble.

View attachment 1363239
View attachment 1363238
Final update. Well- we did it! Had a little delay due to a surgery and general lack of winter motivation, but it is alive!

A couple of knuckle heads can switch out an engine (mostly), if you are partient.

While we had the outdrive out, we changed the gimble bearing, as well.

Had trouble aligning the engine after install. Took it to buddies mechanic in Rancho Cuc. He aligned and fired the engine. Start up video is from him.

Everything works, which is nice! Buddy Jeff took the boat to puddingstone and ran it around for an hour . All is back together now and ready for their annual moth

 

[rightytighty]

Just curious where you went to in Rancho. Looking for a mechanic to re-align the gimble.

Concept Marine

 

[Fun Times]

View attachment 1363239
View attachment 1363238
Final update. Well- we did it! Had a little delay due to a surgery and general lack of winter motivation, but it is alive!

A couple of knuckle heads can switch out an engine (mostly), if you are partient.

While we had the outdrive out, we changed the gimble bearing, as well.

Had trouble aligning the engine after install. Took it to buddies mechanic in Rancho Cuc. He aligned and fired the engine. Start up video is from him.

Everything works, which is nice! Buddy Jeff took the boat to puddingstone and ran it around for an hour . All is back together now and ready for their annual mothers day trip to Pirates Cove.

Ruh Roh, Is it time for an upgrade yet with your buddy?

Mercury 496 supercharger - boat parts - by owner - marine sale - craigslist

Mercury 496 supercharger has about 80 hours comes with everything you see , even a $500 Hardin marine water pump pretty firm on price paid over $10,000 new

inlandempire.craigslist.org

Seems this guy in riverside is parting out a 496, https://inlandempire.craigslist.org/search/bpa#search=1~gallery~0~5

 

[rightytighty]

Just thought I'd update:

The new (to us) engine ran flawless all summer. Exactly as we all hoped. Check the fluids at the end of each weekend (nothing ever needed), add gas for the next weekend and turn the key.

On a side note: we hadn't noticed how much vibration at idle the old package had. It just crept in incrementally. New gimble bearing, proper alignment, and tight motor mounts ( the original had come loose on one side) and voila! Zero rattles or shakes.

Funny how we just remembered them as "normal" until we felt the new and proper normal.