SL 750 Ocean Pro Head

[Polaris_Nut#1]

I have been running double head gaskets on my 95 SL750 ever since hotseat accidently cut them for race fuel [img]/graemlins/angryfire.gif[/img] was supposed to be for pump gas.

I just got a brand new Ocean Pro head from Dennis Kirk on eBay for $69.99

I thought it was a good deal, seeing how slavage yards want $150 for used stock heads.

I'm just looking to run pump gas, and have some much needed reliabilty. :D

Anyone have any tips for use of this head?
I guess I'll start with the thick gaskets

Do I really need to put in the jets it came with?
And is it really ok to ditch the thermostat?

If anyone has a SL 750 with the OceanPro head and Flame Arresters properly jetted, I'd appreciate your input.

Those directions that came with the head leave plenty of room to cover their back sides, and I don't get any responses to the emails I send asking about jetting

[pcalonge]

Not familiar with these heads, but:
If they came with bigger jets, it stands to reason that they are higher compression than stock, so you better start with the supplied jets. If they run too rich, you can always go back to stock. If you run the stock jets and they are too lean, you could easily fry your motor in one run.
There are some good instructions on carb assembly/tuning right here on the SBT site under the tech section.
I have to assume that the Ocean Pro heads were intended to run on pump gas, I'll say 93 octane premium only, but that is only my assumption. Keep in mind that they do not stay in business by destroying their customer's motors.
Check your compression after changing heads.

[pro785lim]

I had a 94 SL750 with a 780 ocean pro head $25.00(using the thick gaskets) yes a 780 head on a 750, running 190 psi per cylinder, ocean pro vortex flame arrestors, aftermarket water box(dont remember the name of it), extended pump and ride plate and a few other goodies

All using the stock jets, I just adjusted the air screws. I did alot of testing on this, checked the plugs alot till i fell ok with the way they were burning. My altitude may be different than yours and using 93 octane pump gas and premixing the fuel. I remove those junk oil injection pumps.

hope this helps

[pro785lim]

And yes, get rid of the thermostat, just dont run it in cold water.

[Polaris_Nut#1]

WOW 190 psi seems awful high, but the alttitude might have something to do with it

I have 150 psi and the motor seems like it is getting to hot to me, yup 2 gaskets on each cylinder to bring it down to that, who knows how bad my squish is off. I had around 165 or 175 with one gasket if I remember correctly. thanks for the melt down hot-seat, says right on my invoice pump gas mod

Ocean Pro says over 160 psi use high octane race fuel.
Anyone know what the compression of a SL750 with stock heads should be with fresh pistions?

Their directions say that "Stock engines vary in cranking compression by as much as 40 psi so keep this in mind when checking your compression" How is that possible? Maybe on a used machine, but they are imply they leave the factory like that

The Ocean Pro head and Flame Arrestors were avalible right thru polaris maybe I can get an anwser out of them on which jets to use

I just hate pulling that carb rack off [img]/graemlins/angryfire.gif[/img] it's like stuffing a big block engine in a porcelain bath tub and having someone say change the crank bearings but don't pull the motor out [img]graemlins/buck.gif[/img]

[Greg T]

Be careful with that head. It is well known for burning up pistons. As has been mentioned often by SBT representatives, compression gauges of the cheap kind are all over the map. With that said, I have consistently gotten around 130 psi on my 750's. As I recall the OP head should bump it to 145-150 with thick gasket and around 155-160 with thin. You will need 92 octane with either. Make sure your fuel pump is good, or switch to the triple output type.

The problem with the mono block head is that it is dependent on all three cylinders being exactly the same height and perfectly plane. this is not a good assumption from a mechanical tolerance perspective. Improper sealing around one of the three cylinders is almost assured. The stock Polaris engines have separate heads for a good reason.

[pro785lim]

I work for the worlds largest Polaris watercraft dealership, 5 years running, I use Snap-on tools($15,000 worth and growing).......

WE build stock to custom race boats and at this time, I am building a 280 HP Polaris watercraft, witch will be seen in my area some time this coming summer.......

I'm just trying to say.......my info on ski's is well thought out and tested......that has made us what we are now.....besides formula one tunnel hull campion two years running......

[SeaLion]

Compression can vary greatly. Some of the variables are altitude, relative air density, humidity, heat etc. Throw in all the various gauges that are available and you can see how a compression test is the least accurate way to see what your fuel octane requirements are. Take a stock ski brand new in California at sea level and the same ski in another state at 1500'. Do a compression check with a calibrated quality gauge and you are most likely to see different readings. Heck even if the same ski travelled from sea level in Cali on the same day to Havasu, you would get different readings. It is however good to use a compression gauge to see either differences between cylinders or to see a blown cylinder [img]smile.gif[/img] It is definitely not a tuning tool and you can't assume that on 1 days test you get 160 lbs and you think it's safe to run pump gas and a week later the variables change and you are running 185lbs and you end up seizing.

[ShowMePro1200]

Does anyone make aftermarket separate heads for the 750 fuji-blues?

Pro785lim - Are you guys in the winter hours now, in other words closed on Sundays? I need to get by and get some parts.

Also, I'd like to see the 280 hp project some time. Might come down back and look.

[SeaLion]

Properly redesigned stock heads work very well. Especially with an o-ring mod. No more expensive head gaskets.

[Polaris_Nut#1]

pro785lim and SeaLion,

Would you recommend using this head? Or should I track down a set of stock heads?

I tried getting my machine to run with the 1 head gasket per cylinder. I put in 105 mains, but the gaskets would still blow out. and yes I checked the torque on them often.

We got snow here already, so I got plent of hours to kill. I just want to be able to get on this thing next spring and not have to worry about reliablity.

The 280HP project sounds cool. I'll never see anything like that around here.

[ShowMePro1200]

SeaLion -

When you say properly redesigned what do you mean in particular. This is from someone who doesn't want to do major modifications to an already good-running "family truckster", but would enjoy having a little extra power to blow the other "trucksters" out there off.

I'm saving the real mods for the future hot rod project I'm wanting.