460 corba making oil

[theguy5000]

I just bought a 1990 225 sundowner with a cobra 460 omc stern drive the guy I bought it off of a guy and was changing the oil on the dipstick looked new but when I started changing the oil it was milky a sign that water is getting in the oil. The gaskets in the exhaust water head too but am I looking at a new motor or is their something to look for that's an easy rebuild?

 

[HT32BSX115]

Re: 460 corba making oil

I just bought a 1990 225 sundowner with a cobra 460 omc stern drive the guy I bought it off of a guy and was changing the oil on the dipstick looked new but when I started changing the oil it was milky a sign that water is getting in the oil. The gaskets in the exhaust water head too but am I looking at a new motor or is their something to look for that's an easy rebuild?

Howdy,

Welcome aboard!

I am not sure what you're asking. How high above FULL is the oil?

The gaskets in the exhaust water head too

??

If you have water in the oil and the oil level is well above full, you likely have a cracked block. You'll need another engine.

You should pressure check the cooling system to determine if the block is cracked.

if it was run in salt water or the exhaust manifolds and risers have not been off in several years, they need to be removed and inspected and at least the riser gaskets replaced.

If they're even the least bit questionable, they need to be replaced.

I am sorry to say that I don't think you can buy manifolds anymore for a 460. You may have to go with very expensive after market manifolds if they're even available.

I had a 460 in my 1987 Four Winns liberator. I was unable to find manifolds in 2005.

They are available once in a while I think for ridiculously high prices. Every once in a while a marine business fails and the old parts are auctioned off. sometimes someone finds new (old-stock) 460 manifolds.....

Good luck


Rick

 

[jerryjerry05]

Re: 460 corba making oil

The dip stick only shows the level.The oil doesn't circulate in the tube, just raises and lowers with the level.
Take the plugs out and see if there is any rust?
Yours might have an oil cooler,possible it's leaking?
Pull the manifolds and check for rust?

 

[theguy5000]

Re: 460 corba making oil

Well I'm pulling the top end apart tomorrow I was inquiring to if their an easy repair I don't know about the extra water jackets in a marine if it could just be a gasket because the top of the manifold was removed and was leaking water to the exhaust or what else it could be other than the motor I do most of my own work I'm being optimistic and hope it's not a cracked block or heads.
What is this oil cooler I've heard that 460 had that problem with that, I was checking the oil from the first time I noticed it was high on the dip stick but I thought it was constant level till I emptied the oil and it was slim

 

[HT32BSX115]

Re: 460 corba making oil

Well I'm pulling the top end apart tomorrow I was inquiring to if their an easy repair I don't know about the extra water jackets in a marine if it could just be a gasket because the top of the manifold was removed and was leaking water to the exhaust or what else it could be other than the motor I do most of my own work I'm being optimistic and hope it's not a cracked block or heads

Before you pull the top end off, I strongly suggest you pressure check the block for leaks. That will tell you pretty definitively if the block or heads have cracks or there are other leaks in the cooling system.

After you pull the (intake) manifold and heads, it'll be impossible to tell.

There are no "extra water jackets" in a marine engine other than the exhaust manifolds and risers (which ARE jacketed)

A cracked block and/or heads are not a show stopper in your case. You can easily get a wrecking yard engine out of a truck. Ford made literally hundreds of thousands of 460's for trucks and motor homes etc. Even a 429 out of a big Ford LTD would work.

You do need to be worried about the manifolds and risers. If they are cracked, leaking or otherwise unusable, you may be "dead in the water"........... You cannot repair them.... you must replace them.

 

[Don S]

Re: 460 corba making oil

Before you go too far, if you have the OMC King Cobra with a cone clutch, and your engine is dead. You have a hull, don't even waste your time with the engine. You can't even buy an impeller for that drive. So why dump money into an engine that is no longer supported in parts.

 

[HT32BSX115]

Re: 460 corba making oil

Before you go too far, if you have the OMC King Cobra with a cone clutch, and your engine is dead. You have a hull, don't even waste your time with the engine. You can't even buy an impeller for that drive. So why dump money into an engine that is no longer supported in parts.

I just bought a 1990 225 sundowner with a cobra 460 omc stern drive

Yeah. (unless it's an 89 model (eng/drive) .......

If that engine/drive is REALLY a 90 model, you may already dead in the water.

Look for your model number.

If it's 754APEPWS (1990) you have the first year for the Cone clutch (King) Cobra

If it's 460AMLMED or 460APRMED It's an '89 model engine/drive and you have far more options.

xxxxxxxxxxxxxxxxxxxx


Now, I just went to epc.brp.com (BRP parts) and looked it up. The BRP parts catalog NOW shows the impeller for a 90 (cone-clutch) model as:

IMPELLER ASSY #0983895

Looks like they're compatible for a whole host of (Cone and Dog clutch) drives.

Evinrude parts indicates #0777128 replaces #0983895

Either I'm needing my glasses (again) or BRP and/or others have decided that the impeller model didn't change over the years......

If this is true, there's going to be a lot of happy people out there!!


983895 IMPELLER COBRA - Sierra 18-3058 - iboats

983895 IMPELLER COBRA - Sierra

983895 IMPELLER COBRA - Sierra Sale Price: $12.16
Save: $5.83
(32% Off $17.99)
Part # 18-3058
No Reviews | Write Review

So if the BRP part number is correct, you can buy that Sierra impeller right here on iBoats!!


Now, if you can buy manifolds, you may NOT be dead in the water......


Hey, maybe I should have kept my 460!!!:facepalm::facepalm:..................mmmmmmmmm maybe not.



EDIT.

Ok, False alarm (for some) .......I looked further into the BRP catalog....

The impeller changed in 1992........... for the 1990, 1991 (early) Cone clutch models, the impeller is the "same" as the "Dogs". For 1992 however, they went to an impeller with a different part number ..........#0987176

All the parts sites I looked at indicate either unavailable obsolete.....meaning that if they have one, you're gonna pay!

3854072 - 987176 OMC KING COBRA WTR PUMP IMPELLER Replaces OEM #3854072.
Part Number 3854072 Johnson 3854072 Evinrude	Manufacturer Evinrude Johnson OMC OBSOLETE
List Price $100.00	Your Price $100.00

 

[jerryjerry05]

Re: 460 corba making oil

Impeller superseded to part# 0777128 Boats . net says they have the impeller in stock. Under $17
Always include the serial#s when posting about ANY motor or problems.

 

[HT32BSX115]

Re: 460 corba making oil

Impeller superseded to part# 0777128 Boats . net says they have the impeller in stock. Under $17
Always include the serial#s when posting about ANY motor or problems.

Absolutely right. As I indicated above,

Evinrude parts indicates #0777128 replaces #0983895

But that impeller fits virtually ALL the "Dogs" and the 90/91 "Cones"

92 and above Cones with the "sea-water" pump on the back of the drive (up to but not including the VP SX drives) requires #0987176 superceded by #3854072

The above part is indicated as

List Price:	$43.96
Price:	$43.96
You Save:	$0.00

PRODUCT OBSOLETE

People with these drives must either scrounge the impellers collecting dust on part facility shelves and/or pay exorbitant prices for them, OR install newer Volvo Penta engine driven (SX style) raw water pumps on their engines.

Which would be my choice.

If the OP indeed has a 90 model, it would use the available #0983895 // #0777128 impeller. Sierra is making couplers again I think.....but his bigger problem will be finding exhaust manifolds if he needs them........ I would not put a new engine with old manifolds in that boat......

The after market SS manifolds will likely be more than a new engine. His bigger problem will be manifolds if he needs them. They appear to be NA. There are after market SS manifolds available but only one of them costs more than a rebuilt engine!! If that's the case, he's likely done with that engine and drive.

 

[theguy5000]

Re: 460 corba making oil

Didnt get a good a good pressure test my boat has an oil cooler but it's leaking water out but can't tell if it's getting water in the oil from their or somewhere else tho any ideas?

 

[bruceb58]

Re: 460 corba making oil

Curious how you did your pressure test since normally, a pressure test doesn't test the oil cooler at all.

 

[theguy5000]

Re: 460 corba making oil

It's external on the back of the motor maybe I did say it wasn't a good pressure test I noticed it leaking and removed it

 

[bruceb58]

Re: 460 corba making oil

You need to pressure test your cooling system. That means plugging the hoses going to the manifolds removing the hose that comes from the sterndrive to the thermostat housing and improvising a way to pressurize your block to 15psi or so.

 

[theguy5000]

Re: 460 corba making oil

Well I'm replacing the head gaskets so I'm too far along to pressure test it now but could you bypass the oil cooler or is it necessary on a boat? I know my truck doesn't have one on it

 

[bruceb58]

Re: 460 corba making oil

Well I'm replacing the head gaskets so I'm too far along to pressure test it now but could you bypass the oil cooler or is it necessary on a boat? I know my truck doesn't have one on it

Curious why you didn't take the advice here and pressure test the block first?

The head gaskets are not likely your issue.

I would put the oil cooler back on once you find another one or get your repaired. I would pressure test the oil side of the cooler to at least see if that was intact and not letting water into the oil. Also not likely since oil pressure is a lot higher than the water pressure in the cooler.

So how much water was in the oil? Enough to just make it milky or was it changing the level considerably? Not sure you really answered that question.

 

[HT32BSX115]

Re: 460 corba making oil

It's external on the back of the motor maybe I did say it wasn't a good pressure test I noticed it leaking and removed it

When you pressure the test the engine, are only pressuring up the block, heads, circulating pump and intake manifold.

The exhaust manifolds, risers, raw water pump, and any (oil/PS) coolers etc, are not included.

Is is possible to pressure test the ex-manifolds but the risers must be removed and you have to make block-off plates ........ any leaks are very hard to discern from the block-off plates themselves leaking. It's not possible to (easily) pressure test risers.

You will be wasting your time replacing the head gaskets if the block or heads are cracked...

 

[theguy5000]

Re: 460 corba making oil

Well I pressure tested incorrectly but the oil cooler was split and I'm changing the head gaskets because they came with the boat my times free the only thing it's going to cost me is the beer per hour some of my buddy's are expensive labourers especially when i do most if it but when I get it back together ill do a proper test I guess but if the motors done for I actually have a rebuilt 460 for a project truck I've been working on that I could repurpose that's build for low to mid range I know I'd need to change the cam but to boats have a thermostat because their wasnt one in the motor that it currently has in it?

 

[HT32BSX115]

Re: 460 corba making oil

Well I pressure tested incorrectly but the oil cooler was split and I'm changing the head gaskets because they came with the boat my times free the only thing it's going to cost me is the beer per hour some of my buddy's are expensive labourers especially when i do most if it but when I get it back together ill do a proper test I guess but if the motors done for I actually have a rebuilt 460 for a project truck I've been working on that I could repurpose that's build for low to mid range I know I'd need to change the cam but to boats have a thermostat because their wasnt one in the motor that it currently has in it?

If only the raw water "side" of the oil cooler is leaking, it just runs onto the boat (and sinks it if the bilge pump(s) cannot keep up or the battery goes dead etc)
But it will not cause water to enter the oil.................OTOH, It's very possible that a leaking oil cooler (oil side of it) can allow water into the oil if the boat is sitting in the water (engine NOT running) for extended periods of time and the cooler is below the water-line.


There's nothing wrong with using a "truck" 460 in a boat with a "wet" exhaust.

It MUST have a "marine", RV or even "truck-type" camshaft. You want a cam that gives you the torque between 2000-4500 RPM or so..... If you use a "lope-y" or high duration/overlap etc cam, you'll likely have varying degrees of reversion with very bad results...

Someone left the t-stat out........you should not run without a t-stat.