Special Impeller for 2.3L OMC?

[Keyboardman]

While reading the service manual on my 2.3l, I noticed it stated that the impeller for the 2.3 and the 3.0L engines has a specific impeller for those engines. I looked one up and sure enough, it's different than what was in my 2.3L when I got it. I'm working on the overheating issue right now by starting with replacing the corroded and pitted adapter plate, seal and O rings. I guess I better get the correct impeller that's supposed to go in it. I'm assuming the housing is the same as the standard type by cross referencing numbers. They seem to be the same. Why is the short type impeller use for these two engines alone? Will it help my water flow problem? Thanks.

 

[HT32BSX115]

They seem to be the same. Why is the short type impeller use for these two engines alone? Will it help my water flow problem? Thanks.

Howdy,

Well, the impeller for the (Cobra) 87-89 2.3L, 3.0L, 4.3L, 5.0L, 5.7L & 7.5L (and newer Dog-clutch) packages are ALL specified as part number 0983895 (REF: http://epc.brp.com/ )

And if you have any dog-clutch Cobra for example, They to appear to ALL be the same part number.

Looking at all the models available listed at http://epc.brp.com/ It also appears that the "2.3L" engine nomenclature was only used from 1987 to 1990. (86 and earlier it was called something else) And it appears it was discontinued in 1991. When the smallest engine was the 3.0L

So for the years that there was 2.3L and 3.0L engines available that were dog-clutch (Cobra) drives, the impeller appears to be the "same"


I guess the specific answer to your question is, without knowing what eng/drive package model number you have, it's probably not possible to determine what impeller you should use.

Maybe post your eng/drive package model number?

Year model of your boat is not usually all that helpful since all boat manufacturers still use "last years" model engine/drive packages if they have them on hand when assembling the boat.

Also, if you cannot figure out what you have, I.E. someone in the last 40+ years had swapped out the engine and drive etc..... post a picture of the drive and engine and someone here might recognize it.

Regards,


Rick









Regards,


Rick

 

[Keyboardman]

Hi Rick! Thanks for replying to my post. My boat year is a 1991 model with the 2.3L engine. The Vertical Drive is a model # 985683 2.3L. The last year I can find parts for is a 1990 engine so I've been assuming that it's a 1990 left over engine/outdrive as they didn't make the 2.3L in 1991. That being said, I did some research on the different years of the 2.3L and the 3.0L from 86 to 91. They all used the same standard impeller except for the model year 1990, both the 2.3 and the 3.0 used the different impeller and cup. I'm wondering why they used this type for only this year? The 1991 3.0L goes back to the standard full size impeller. I did read something about how mercury made different impellers as far as low pressure/ high volume vs low pressure/low volume? I don't really know what that might be all about or even related to this odd ball situation. LOL! Anyway, I'm a "rebuild it like it was" kind of guy and am going to use the one that the factory put on it for that year. As soon as it arrives that is. Thanks for your help.

 

[HT32BSX115]

They all used the same standard impeller except for the model year 1990, both the 2.3 and the 3.0 used the different impeller and cup. I'm wondering why they used this type for only this year?

Yes. I see that!

And it's pretty strange considering that the same impeller and housing/cup were the same for all "Dogs" all the way up to the 460 King Kobra!

For yours however, if the "One-Off" impeller/housing/cup are harder to find, I would switch it all to the more common one. More flow wouldn't be bad.

Over heats are almost always failed/damaged pump, or obstructions in the cooling system...... Either obstructions in the supply (from the pump) or obstructions in the exit (risers, manifolds, etc) or a stuck/clogged T-stat.....oil or PS cooler (if installed) and sometimes in a salt water engine, clogged (or nearly clogged) head(s), block and/or circulating pump, all due to rust.

 

[Lou C]

Interesting, I wonder what lead them to bother to make a smaller impeller for the 4 cyl engines? Too much flow leading to colder running or increased water pressure?

 

[Keyboardman]

Old corroded adapter plate removed and replaced. Pain in the butt tapping 3/8" threads in worn out alum. I had to go up to 7/16" on one hole. That old adapter plate was not sealing anything for sure. The factory specific impeller and cup are available and I have them coming in the mail.

 

[Lou C]

Great work there!
BTW the 2.3 and the 2.5/3.0 are both 4 cyls but very different. The 2.3 is the same engine Ford used in tens of thousands of Mustang IIs, Mercury Bobcats, Ford Fairmonts, Mercury Zehyrs, and Ford Ranger pick ups. The 2.5/3.0 is a GM industrial engine used in boats, forklifts etc. Parts for the 2.3 are limited because only OMC used it and only for a few years. Being an overhead cam engine it might actually give better performance than the OHV GM engine. Keep in mind it has a rubber cam belt that can break and leave you stranded (happened to a girlfriend of one of my brothers). The key is that you crank it to start and the distributor is not turning, the dist on those was run off the cam drive.

 

[Keyboardman]

Thanks Lou, I've had the Ford 2.3 in two Pintos and a Mustang. The Mustang was a turbo. Timing belt failure has happened to me before. I put a new one on it when I assembled the replacement engine. Also I have a spare used one along with spare cooling hoses stored in the bow. They are not the most powerful engines, but I'm not a speed demon and just cruising around 20 is fine with me. The Boat was $100 and I knew I needed to replace the seized old block. I found a 1986 Capri with an 86k mile 2.3 in it. I changed it over to a Marine application. A new aftermarket exhaust manifold set me back a bit though! It should last around 7 yrs or so here in salt. Longer than I'll probably own the boat.

 

[Lou C]

Looks good! Those blue 2.3s always remind me of the good old days of simple cars that you could fix yourself! My cousin had a Mercury Capri (European Ford Capri) with a 2.0 Ford OHC engine. Nice little sporty car of the 70s.

 

[Keyboardman]

Have the new impeller and cup installed. Now have to take it to the boat ramp to see if it's going to pump on it's own. From what I've been reading, the impeller has to be submersed to prime. I can get water in a dock box up to the anti cavity plate and the intakes but that's all. If the weather ever clears here on the east coast, I'll check it out. Thanks for all the help guys!

 

[HT32BSX115]

From what I've been reading, the impeller has to be submersed to prime

Yup,

Pretty much true. Those rotary type pumps don't pump air very good at all. Fastest way to destroy an impeller. They get very hot very fast.

With the boat in the water, the pump is below the "resting" waterline. On a plane, with the pump already primed, it won't lose it unless there's a huge leak in the drive (between the water pick-up and the impeller intake) and it can suck air.

If you're chasing a problem in the future, you can test by using a clear vinyl hose from the pump discharge to the T-stat housing and observe the hose for bubbles at various RPM