help to identify vintage sea ray please.

[david davies]

I'm a new member here as of about 15 minutes ago.

my question to you all is can you help me identify this derelict Sea Ray I just bought?

in My youth i had a 17 with a mercruiser 4. the boat was, i believe, a 73 model with that lovely curved windshield, it had a walk-through.
yesterday i picked up this boat alongside the road for 200.00. I bought it because I love it. They are beautiful to look at. It's derelict, with a chev 6 .
This boat has a curved windshield with no walkthrough I did not get a title or a registration.
i will make the effort to post pictures on here. the deck is badly checked, the cutwater is clean almost no wear, and of course, the interior is shot, outdrive missing and the engine is of dubious value, it's coming out to go into a friend's boat. Trailer is EZ load.
the pic loaded oddly enough. apologies. but it serves its purpose


What year did S.R. option these runabouts with the curved windshield? I noticed the avatar of forum member El Capitan has a similar or identical boat to this one. Can you help me identify its probable vintage? It was full of garbage and I've not gone looking for vin yet, so i can't even help with those numbers.
thank you and greetings to all of you.

 

[JHornsby3]

Your in Oregon? Does it have the inline 6? If so I can help you to help me. I have the drive for a late 70's inline 6. My 1977 lake boat has the same trailer. And the same color gel coat.

The Hull ID Number is on the transom. Starboard side by the rub rail.

 

[Little Ducky]

Really that's the best picture you could take?

 

[vandal]

It is a 1971 model is 180.

 

[david davies]

Vandal: 1971 model. thank you for this.

Little Dicky: best picture: cool it.

Jhornsby3: yes up in Scappoose: rub rail VIN: I looked there and on the port side, nothing. your described location is where my other S.R. had them.
I then assumed it would be under the deck on transom or dash, but too littered with garbage at the time with heavy rain.

How can I help You? If I'm able, I will do so.

The six is coming out and will share its parts with a friend's boat. But there are a number of sixes here; I'm on the Columbia obviously- There are a ton of boat parts about the place, if you're looking for that. or if you're looking to sell, i may be interested.
Honestly, I did not buy this boat with any intention other than to preserve it in its current state. It was an impulse buy; the models are extremely uncommon in Oregon, and to my eyes, very attractive.

This winter It's getting shrink-wrapped under a boat cover and a dehumidifier inside on a timer to work six hours a night.
The hope is to wick out the moisture utterly from the innards of the vessel, under the floor and bow, pull fuel tank, etc. The dehumidifier will drain through the transom through a 1/4 tube.
Summer brings a sober appraisal of the value of the vessel. At the very least it will see duty as a swim platform at the farm in the pond for the children. At most: a proper repower and then ...

question: in that day swim platforms were not standard?
if I remember correctly our 73 had one but I could be confusing it with a later model.

 

[Ike]

If it's a 71, it didn't have an Hull Identification Number. They weren't required until late 72 and Sea Ray started putting them on 1973 models. My 72 190 doesn't have one either

 

[david davies]

thank you for this. it solves the mystery of my missing VIN.
id like to find another of these 71's they are lovely

 

[DaveKamp]

I have TWO... my runner (shown in the avatar) originally fitted with '120/140' 4cyl 153ci four, got a complete refit and interior, with a rather strong 250ci inline from a houseboat. Don't let anyone convince you that an inline six cannot generate power- that cleaver propeller is there for good reason.

The second one is slightly older, and it does NOT have a Hull ID number... in similar condition to yours, the interiors tend to go away quickly when they do. It still has it's inline six.

Prior to the fuel-crisis era of the early '70's, most hulls by most manufacturers were either flat, or had a slight 'rocker' at the transom (upward taper), while after, most had a slight 'hook'. This was done to help low-speed planing, but at the expense of high-speed performance. Both of mine have 'rocker', while my '77 SRV-22 and 74 SRV-240 have hook. They're certainly NOT in the same performance envelope (due to balance, wind drag, power-to-weight ratio, and sheer mass), but the planing character resulting from the difference is very noticeable. The SRV-180 with this windshield runs surprisingly stable at 70+mph, albeit, with very little of the hull wetted.

FWIW- this hull was available with the Ford 302. There was one in my local dri-stak, and his was not NEARLY as quick as my inline six... but to his merit, his was not fuel injected, with 10.5:1 compression...

 

[david davies]

tell me more about your six.
10.5:1?!

 

[DaveKamp]

Actually, I'd hafta pull my files, something tells me I might've gone 10.75:1... I built several other engines since then... but it was up there.

A raw-water marine engine runs substantially lower cooling water temps because they run at atmospheric pressure, not sealed like automotive application. This, and colder plugs, means you can get away with internal combustion antics that otherwise wouldn't be possible.

I used SBC 307 flattop pistons, 5.7" SBC rods, and it was either 0.030 or 0.040" overbore to clean up the holes. The stock head got 2.02/1.50 valves and modest porting, new guides and thread-in rocker studs. Camshaft is an Elgin, I had it ground with an RV profile, with .512" lift. I used SBC Rhodes lifters, and Harlan Sharp roller rockers, had to be careful with valve spring selection to avoid coil bind. I opened up the holes for larger pushrods, but don't recall which type or size I wound up using. Oil pump is standard, cam gear setup is stock, aside from drilling and threading the end of the camshaft to allow a retainer bolt to keep it from walking off. I used a standard flow/pressure oil pump... cleaned up the head and side cover returns to get oil back down, had a deep baffled pan made in attempt to keep windage under control.
Used the standard marine flywheel, but had to put on an aftermarket balancer, as the OEM wanted to shed it's ring.

I used the OEM style marine intake/exhaust manifold. Intitially I used a Crane 2000 optically-triggered ignition in the Delco distributor, with a Holley Marine Pro-Jection system, but replaced that with a Rochester TBI-220 (common for early '90's V6/V8's) and GM automotive injectors, a modified GM EST-HEI distributor (from a 5.7, running a 454ci marine module) and a GM 7727 ECM for both fuel and ignition timing management. I left the exhaust bellows off the drive, used a stock 140F marine thermostat.

With the 7747, I took the Park-Neutral input, and connected it through a relay that was wired into the Neutral Start Switch. What I found, is that this engine would NOT idle kindly or shift nicely without running several degrees LESS of idle advance, and it wouldn't stay solid in gear WITHOUT that advance. The '7747's ignition mapping had a page dedicated to PARK/NEUTRAL emmissions operation... so whenever that neutral state was detected, the'7747 would switch to the park/neutral advance map, dropping back 6-7 degrees. (the map's secondary axis are air temp, and manifold air pressure!). When in-gear, I advanced the 6-7 and got very respectable idle stability at 650rpm, and pulling it into neutral granted a crisp response to shift interrupt (yeah, gotta do that to get the shift dog to release) with a steady 650rpm attitude.

The combination of factors gave the power package a very noticable bump in torque curve around 1600rpm... when coming out of the hole, the Rhodes lifters would pump up, and duration and lift would respond. I made the fuel curve appropriate, as the exhaust backpressure would relieve rapidly above 1400, so it went from being fairly tame, to beastly torquey just a few mph short of being on plane.

Family and life kinda got in the way of using it, but now that I have one in, and one soon college-bound, I'll have time to uncover and wake it up. When I did this build, I was 25 years younger, and did NOT have access to many things I have now. I want to attend to several things, and I MAY do a few others in the process...but if I were to do it again, here's what I'd do:

1) Dry sump oiling. It spends lots of time in the air, and it is VERY noticeable when oil in the pan ventures up into the crank's neighborhood. Dry sump will eliminate lots of little problem points, as well as give me the opportunity to employ a water-cooled oil reservoir.

2) Custom made intake/exhaust. The factory cast unit is big and heavy, and doesn't flow particularly well- it flattens out the torque curve around 4400rpm.... such that it exhibits a significant loss compared to the dyno tests using automotive performance intake and exhaust. I would probably also pipe it out through-transom in whatever best-wayI could, without creating a massive racket.

3) Crank-trigger distributorless ignition, and a MegaSquirt (or other open-source/aftermarket) ECM system. The '7747 is a good unit, but adjustments require burning a new prom. I have a PromUtator, and it did work well, but technology has allowed many practical improvements that are so much simpler to manage.

4) Sequential port (not throttle body) injection, and a LUMP PORT kit (to improve breathing)

5) A modification of the drive, or swap to an aftermarket performance flavor (a Bravo?) that will not suffer from the 1R's 5000rpm limit. This engine's torque curve has much more to offer above 5k.

IF I were to be able to choose a different prime mover carte-blanche, I would PROBABLY select the 2008 GM LL8 (Vortec4200) and HOPE that it's tall stature would not be hard to work in under the engine cover... either that, or a 4.0L Jeep six with a WhippleCharger.

 

[david davies]

wow .
the chev will, take.512 lift!
are you zero deck with the piston?
valve relief?
a 140 thermostat, thats rather cool from my land based sixes,but to control detonation ?

love the dry sump idea.
simple and lotsa space with larger capacity of oil.
how do you control oil temps with fresh water cooling of oil? a thermostat?
feasibly with the oil cooled separately, you could diminish flow to the rest of the engine, possibly use a wet header?
ive been toying with cooling my sixes through the casting ports or so- called " freeze plugs" with a manifold and six 33/8-1/2" lines and threaded plugs operated by a davies craig electric water pump.

there are fantastic benefits to be had by this but of a diminishing return value, it will ( i think) even out the temp difference between cylinders and its hoped , reduce the amount of of coolant needed.
this is all on a land based engine. ive almost zero experience with marine engines. there is a growing body of knowledge turboing the ford 300 inlines , im new to GM inlines .
but a turbo has proven the six a fearsome competitor to the big and heavy v8.
also anchoring that much power aside from obvious transmission issues, does it have any negative effect on stringers, or attaching points?
so many questions . what you have done is a dream combo.
arenson surface possibly? assuming no skiers etc.

huge applause for this.

MS rocks, and will make even greater strides.
sequential in my experience has been greater headache than its worth. but im amateur at tuning.
i mean , batch fired at anything over 1500 is essentially identical.


MAF seems simplest
but many tuners seem to be digging the speed density .

did GM EVER efi the 292?

also, the coil near plug GM. thing is clean on a six.

EDIS 6 is bulletproof.
70 in a sea ray boggles.
that' s unimaginable to me. with its weight it must be fairly stable at that speed.


THANK YOU for this.
it excited the imagination. really.

a clever builder in Wisconsin has recently built a ford six with super- turbocharged . wicked. deadly etc

 

[DaveKamp]

iirc 140F thermostat is what MerCruiser fitted the inline fours and sixes from factory. Realize, raw water cooling lives by a totally different set of rules. On an automotive application, the thermostat is responding to block circulatory temperature to divert high-temperature coolant through the radiator, where it returns at a lower temperature. The differential from high to low side is fairly predictable, but the engine load, in general, is low... they may be capable of several hundred HP, but spend most of their time coasting or just working hard enough to maintain speed against wind drag. Even a large truck engine, or a locomotive only operates at full load for PART of it's running hours.

A MARINE engine, on the other hand, cannot COAST. Yes, when I chop the throttle from 50mph, it will be spinning down with no load (the prop actually yields some impressive drag),but the marine prime mover is under a full crankshaft load ALL the time... the only thing the throttle is doing, is varying the fuel-air volume to either maintain, or increase speed against wind and hydraulic drag. This means there's a considerably higher amount of waste heat to dispense.

We cannot use a pressurized system or additive coolant to alter boiling point... hot spots that occur WILL boil... so the tactic has to be to keep the coolant flow high enough to keep hot surfaces wet at all times... meaning... steam MUST not be trapped.

The marine engine resolves this by use of the infinite-heat-sink philosophy... large volume of flow... AND, it's coming in at a significantly lower temperature... generally, it will never be higher than 103F or so, and usually, it'll be somewhere 'tween 35F and 90F, and for MY boat... usually more like 65 to 85F.

Oil-cooling in a recreational marine circumstance isn't too much of a problem- on any 70+f day, raw water flowing through a liquid-to-liquid heat exchanger doesn't need any fancy consideration. IF it was 50F water, it might be better to have a bypass circuit somewhere downstream of the block, but prior to exhaust manifold... but due to the marine duty cycle being continuous in loading, it's not easy to 'over-cool' the engine oil.

Fancy block cooling isn't really necessary, nor is the head cooling a considerable problem... investment in resources there really don't yield much, as it's not a point of weakness or limitation.

In a MerCruiser R/1R/Alpha/Alpha One SS drive, there is basically NO engine output torque on the stringers... The engine torque moment is through the flywheel cover housing, into the transom plate. The stringer loading is that which results from engine mass responding to hull motion, and in the case of the inline six and four, it's actually not on the STRINGER, it's on a block in the front of the bilge, as the inlines are supported on a single-point mount to a wide aluminum casting 'foot'. This isn't to say the loading is insignificant... a 17ft boat tends to respond swiftly to aqueous elevation changes, and there's been quite a few times that I've had an unloaded prop, and a hull begging for a tail-number... it just happens, and the alternating pounding and weightlessness demonstrates excellent reason for dry-sump lubrication... I didn't know then, and I've found that even with a pan and scraper, that oil becomes a chocolate milkshake really easily.

My GREATEST reason for stepping away from TBI basically come down to plumbing. It resolves issues of plumbingspace.

The 250ci six is six 42ci cylinders in a line. Compare it to a 153ci four (38ci per cylinder)... both are flowing down the starboard side of the engine, to an elbow, then over, where discharge cooling water is added, then down, through the transom plate, to exit through the drive leg, or (in my case) out around the gimbal housing at a level about 14" closer to the surface than the prop hub. Compare this to a 350 V8: 43.75ci per cylinder (so a little larger), but they flow in TWO banks... four left, and four right. Now, in all three examples (V8s and V6's prior to'85ish being 'log style' exhaust), the exhaust flow from the rearmost cylinders exits a short distance to the elbow, then overboard. The NEXT pair forward, must exit and flowpast the rearmost. The NEXT pair forward flows past TWO OTHER, and finally, the forwardmost pairs flow past THREE others.

Those other ports are flowing, and while they aren't spitting exhaust at the SAME moment, they ARE contributing to exhaust exit flow, thus, the restriction, especially with cooling water flowing into a submerged exhaust, is limiting cylinder scavenging... and reducing intake vacuum.

On the inline six, you have FIVE OTHER CYLINDERS belching exhaust down that 'log' before getting to the elbow... effectively, that inline six log and elbow is trying to flow almost 50% MORE than the V8 log and elbow, and to add insult to injury, the TUNING for it basically doesn't exist... and this is why guys who slap a frumpy automotive cam into a boat motor wind up with no better performance, and usually worse, with no idle.

As far as intake, you have some close, and some far ports... and with it all together in the same casting, it is NOT reasonable to expect that port volumes will be well-equallized between cylinders... not on intake, and certainly not exhaust.

Going to a multiport, means a handmade exhaust fabricated with appropriate liquid cooling jacket, and a riser elbow ejecting to a low transom exhaust port would also have to be done... which would require plenty of patience, materials, and money... but it would offer opportunity to improve flow.

But here's the gotcha: The R/1R/MR/Alpha/Alpha One SS family of drives does NOT like high RPM... they do not cool and lubricate well once above 5k, and they melt the upper gears... and no drive shower or remote lube bottle will prevent it. The drive will take surprising amounts of torque, but spin 'em fast, and they die young. I didn't pursue improving my inline's breathing, because the marine log's flow efficiency starts it's rapid decent around 4700rpm. IF I found a way around it, there'd be a whole lot more HP on the graph, but to make use of it, the drive would be well above certain-death zone. Even when I run it fast, I don't keep it there for long, and there's good reason why kept several spare drives rebuilt and ready.

 

[DaveKamp]

GM MAY have experimented with a TBI on a 292, but I doubt it was of any significant volume if they DID. I DO know that the 292 will respond verywell to boost, and it'll break 500ft-lbs in mid-range with no substantial lower-end work. Some will disagree, but it's a 7-main-bearing block... and if one looks carefully, there are FORGED cranks out there for the 230,250, and 292.

IF I were really, really nuts, I would do the intake/exhaust thing + dry sump, then MAKE a surfacing drive setup that would BOLT ON to the MerCruiser gimbal setup... essentially go direct drive, and find some way to fit a clutch and a hydraulic throwout bearing inside the flywheel housing. I'd lose reverse...

And with that setup, I'd probably dump a huge wad of resources into something that would go fast enough to require alierons, elevators, a rudder, and some OTHER way to cool the engine as I hurtle over sandy island beaches basically out-of-control... but I have other projects (like a new workshop) that require my attention, and my insanity is already an excellent challenge to the domestic tranquility of my domicile.