Mercruiser 165 inline 6's... or not ?

[silviasurfarn]

Hi, newbie here, need help identifying engines in an old Formula 233 from 1970.

Thing is, the owner wants to sell off the old inline 6's and replace with a single V8. I just might be interested in buying the engines and use for parts, possibly replacement, of my 2 x Mercruiser 160hp 250 CID IL6's from 1968. I believe virtually any Mercruiser 165 IL6 will fit into my boat. The outdrives in my boat are 2 x pre-Alphas (MC 160) with 1.65 gear ratio.

In the Formula there are a lot of things indicating an original installation in 1970 with 2 x Mercruiser 165's and pre-Alphas (trim pumps, alternators, starters, carbs etc) but I suspect the engines and outdrives have been replaced over the years. Today one outdrive is a pre-Alpha from 1980 or so, the other is an Alpha Gen1, and I don't know the ratio but guess/hope it's 1.65. The engines are clearly inline 6's, but the engine blocks are blue, and the covers don't have the Mercruiser logo. I cant find any engine numbers, only cast numbers. I suspect they might be from some old truck or so ? I can't even be certain that they're 165hp, who knows, they might be 200hp in which case the outdrives might even have a 1.84 ratio.

It would be nice to know exactly what kind of engines that are mounted in the Formula. Any ideas ? Cast number is 3994256 GM, and there is some more info on the block: CON 2 ... can't tell ... 4 0 together with a clock (!).

I've enclosed a couple of photos.

 

[Fishermark]

Re: Mercruiser 165 inline 6's... or not ?

It does look like they may have come from a truck - but yes, they do appear to be your basic Chevy 250 engines. The side lifter covers appear to be stamped steel instead of aluminum, which would lead me to believe they were truck engines at one time. But that's not a problem.

 

[Fishermark]

Re: Mercruiser 165 inline 6's... or not ?

Just a quick follow up - I couldn't find the casting number you supplied, but if the actual number is 8994256, then according to this site, it is a 64-67 292 engine. I am not familiar enough with the differences to say what issues you may run into. Just something to look into further for you.

 

[Don S]

Re: Mercruiser 165 inline 6's... or not ?

Looks like OMC blue to me. From the stringer drive days.

 

[EddiePetty]

Re: Mercruiser 165 inline 6's... or not ?

.....anybody notice the automotive type fuel pump?

 

[Fishermark]

Re: Mercruiser 165 inline 6's... or not ?

.....anybody notice the automotive type fuel pump?

I don't know if it is automotive or not, but I know many, if not all of the early marine pumps had no provision for the fuel overflow line.

 

[kilowatts]

Re: Mercruiser 165 inline 6's... or not ?

Hi Guys:

(i) The side covers are basic Mercruiser issue
(ii) They're definitely not 292 engines as they don't have the higher block and the side mount.
(iii) Mercruiser switched to the marine fuel pump (with the vent) in the late sixties early seventies. The transom plate is the older early seventies model too.

I purchased 2 similar engines, also painted blue and I believe they were rebuilt by a reputable machine shop who routinely repaint their rebuilds in blue. This may be the same case, although as Don said they may well be OMC!

I think the answer to your question is:

If they're the right price, buy everything and do the basic tests. If they are in good to repairable shape then you have a pair of stellar marine engines. I would tend to make sure both outdrives are matched though. Good luck.

kilowatts

 

[silviasurfarn]

Re: Mercruiser 165 inline 6's... or not ?

Thanks for all your help

I personally think the fuel pumps are original Mercuisers (from Carter). The inner transoms have the same general design, and the same kind of kill switches, as my transoms from 1968. That was one of the things that led me to believe in an original Mercruiser MCM 165 and MC 165 setup in 1970.

Since I now know - thanks to all of you - the engines are not 292 CID 200Hp inline 6's I think I can go on and consider buying them. Even if they might be truck engines I think the cams characteristics are close enough to the marine cams. Hardened valve seats might be an issue but I can live with possibly having to use lead replacement additives. Brass freeze plugs, if not there already, are easy to mount. All the other marine parts such as carbs, starters, alternators, manifolds, elbows, etc are original Mercruiser parts, I think. And if the engines are rebuilt marine engines, or original OMCs, then even better. Either way, they should work with my MC160 outdrives.

I might just consider buying one of the outdrives, too. Think I'll wait until the engines are removed and then count the number of prop revs to determine gear ratio. If it's 1.65 then I might make him an offer, if it's 1.84 then I'll forget it.

Once again, thanks.

 

[gettaway]

Re: Mercruiser 165 inline 6's... or not ?

they look like 165's to me, here are photos of mine

 

[dpoff]

Re: Mercruiser 165 inline 6's... or not ?

I miss my 165/6

 

[silviasurfarn]

Re: Mercruiser 165 inline 6's... or not ?

I agree, they are 165's but probably not original Mercruisers. And yes, they sure are great engines. Love to start them up and listen to that sound... two IL6's hummin together.

Still haven't figured out what to do. Contemplating buying remanufactured IL6's instead, and perhaps one of the pictured engines too (think I need to replace some marine parts like a fuel pump, distributor etc so I might as well buy it for the parts).

 

[gettaway]

Re: Mercruiser 165 inline 6's... or not ?

I think your engines are marine engines, and the fuel pump looks just like the ones on my Mercruiser 165's. My distributors have a gasket on the cap and a rubber grommet where the ignition wire passes through the side of the housing. look to see if the alternator has the screen mesh on the back side You have a marine manifold and thermostat housing
Id say they are mairnized. if they were rebuilds or if the valve covers were replaced the original OMC or Mercruiser serial plates would be gone. My original serial plate was a mercruiser 'decal" on the valve covers.

I bout these two engines as running take outs with less than 400 hours on them. I cleaned and painted them and have installed them in my 32' sportfisher boat. I runn easily at 12 knots and top out at 20

best part is they are very fuel efficient, @ 12 knots, I am only using about 4 gallons/hour total , plus they sound great!

 

[gettaway]

Re: Mercruiser 165 inline 6's... or not ?

took another look at your photos, the valve covers are cast aluminum mercruiser covers. they are identical to the covers on my engines.