Active Active   Unanswered Unanswered

Leaded vs. Unleaded Fuel and winterizing additive

Keeping your powerboat under power is a lot easier with good advice. Post your power systems questions here.

Moderators: Don Vogt, Al Benton, Don Ayers

Post Reply
User avatar
71Lancer19
Posts: 8
Joined: Fri Aug 08, 2014 7:01 pm
Location: Pacific Northwest

Leaded vs. Unleaded Fuel and winterizing additive

Post by 71Lancer19 » Sun Nov 02, 2014 4:51 pm

The manual for the 307Q engine advises using leaded gasoline with minimum octane of 92. All fuel I've found in my area is unleaded with a max octane of 91, so I've been using ethanol free, unleaded 91 octane gas.

Is this a problem? Should I be using a fuel additive or find a source for leaded fuel?

Is an additive like Lucas Upper Cylinder Fuel Treatment sufficient to replace the benefits of lead in gasoline? Lucas states it on their product page, but just want to confirm with this group. Should I have any concerns using this fuel treatment in addition to a Stabil fuel stabilizer?

I'm preparing to winterize, and I'm trying to locate a replacement to the Chris Craft recommended fuel conditioner and valve lubricant (part no. 56. 00-20629). Will this fuel treatment suffice for winterization?

Thanks for any help!

User avatar
mfine
Posts: 1405
Joined: Sun Jun 06, 2010 8:16 pm
Location: Pittsford and Penn Yan NY

Re: Leaded vs. Unleaded Fuel

Post by mfine » Sun Nov 02, 2014 5:04 pm

There is no source for old leaded auto fuel. The octane rating is not a problem, the old 92 number is a different testing method than is currently used is the US for unleaded fuel. If the engine has been rebuilt in the last 20+ years, it probably already has hardened valve seats and is setup to run unleaded. If not, there is plenty of debate about the use of the additives.

User avatar
71Lancer19
Posts: 8
Joined: Fri Aug 08, 2014 7:01 pm
Location: Pacific Northwest

Re: Leaded vs. Unleaded Fuel and winterizing additive

Post by 71Lancer19 » Sun Nov 02, 2014 5:10 pm

Thanks for the quick reply! I actually just updated my question to ask about a Lucas fuel additive and whether I can use it for winterization. Is there a recommended aftermarket fuel additive (Chris Craft part no. 56. 00-20629) and oil supplement (Chris Craft part no. 56. 00-20630) for winterization, assuming the Chris Craft brand fluids are no longer available?

User avatar
quitchabitchin
Posts: 568
Joined: Tue Dec 02, 2008 9:48 pm
Location: Oxford, OH

Re: Leaded vs. Unleaded Fuel and winterizing additive

Post by quitchabitchin » Sun Nov 02, 2014 6:07 pm

I use 93 octane pump gas, ethanol free if I can get it. I also always run the Lucas Fuel treatment in every tank as I do in all of my power equipment as well. For winterization, i use Stabil fuel treatment and fogging oil down the carburetor to inhibit rust in the cylinders. This is obviously in addition to ruining the engine up to temperature, then adding RV antifreeze to the water intake to cycle through the engine.
FLASH1969 Chris Craft Cavalier Ski-230 HP 327Q

CCABC Board of Directors Member

User avatar
71Lancer19
Posts: 8
Joined: Fri Aug 08, 2014 7:01 pm
Location: Pacific Northwest

Re: Leaded vs. Unleaded Fuel and winterizing additive

Post by 71Lancer19 » Sun Nov 02, 2014 6:26 pm

What's the point of RV antifreeze if you need to drain the cooling system, assuming standard non-closed cooling system?

User avatar
drrot
Posts: 1890
Joined: Mon Nov 14, 2005 12:28 pm
Location: Three Lakes, WI
Contact:

Re: Leaded vs. Unleaded Fuel and winterizing additive

Post by drrot » Mon Nov 03, 2014 8:13 am

On your particular engine you can't drain the intake manifold. Either run the engine and fill it with anti-Freeze or pull the big plug on the intake and suck out all the water you can. Then pour anti-freeze in the intake. Couple bucks now will save a pile in the spring.
Jim Staib
www.finewoodboats.com


1947 Penn Yan 12' Cartopper WXH474611
1950 Chris-Craft 22' Sportsman U-22-1532
1957 Chris-Craft 26' Sea Skiff SK-26-515
1968 Century 17' Resorter FG-68-174

User avatar
71Lancer19
Posts: 8
Joined: Fri Aug 08, 2014 7:01 pm
Location: Pacific Northwest

Re: Leaded vs. Unleaded Fuel and winterizing additive

Post by 71Lancer19 » Mon Nov 03, 2014 2:49 pm

Got it - I had not considered the intake manifold yet. Thanks for saving me some time. The manual advises to remove the square head pipe plug from the intake manifold and then pump water out using the oil sump pump. I'm guessing this is where you would then pour antifreeze back in? Would you put the plug back in place, or leave it off for the winter? Are there pockets of water that are hard to get to, or should filling it up with antifreeze be sufficient?

Just did a bit of reading, and this seems to be a point of frustration for other owners as well. The goal is to get antifreeze anywhere there is a water cavity, so the best solution seems to be:
1- Per manual's instructions, pull drain plugs on risers, cylinder block (use wire here to unclog any passages), seawater pump cavity, oil cooler, circulating pump. Suck water out wherever possible.
2- Put glycerine in the seawater pump cavity and turn engine over a few times
3- Pull square head pipe plug on intake manifold, suck water out, pour antifreeze in.
****Does it make sense at this point to plug the intake manifold and then turn the engine over a few times after the block has cooled down and the thermostat closed to circulate the antifreeze through the engine block? I'm guessing since water has already been drained from the intake there may not be enough intake water to generate enough pressure to circulate the antifreeze, and I'll just end up damaging my impeller.

What if after cutting fuel and running the engine until it stops (still in the water), I pull the boat out of the water and turn the engine over while it's still hot with the thermostat open? Would this cycle water out of the intake manifold and reduce risk of water pockets? Fuel would be cut off, so there's no combustion here, just battery turning the engine.

I read another post from a guy that goes through several cases of antifreeze each time he winterizes, presumably sucking them up from the seawater intake on the sterndrive. This seems wholly irresponsible, financially and environmentally. Am I summarizing this problem well? Any other tricks?

jim g
Posts: 1003
Joined: Wed Dec 14, 2011 10:55 pm

Re: Leaded vs. Unleaded Fuel and winterizing additive

Post by jim g » Mon Nov 03, 2014 9:44 pm

If you winterize your boat using anti freeze and have a thermostat you have to run the engine up to full operating temperature to get the thermostat to open after the thermostat opens you add the antifreeze.

Or another way of doing it is to drain the engine then start it up and run antifreeze through it.

User avatar
tkhersom
Posts: 971
Joined: Wed Feb 27, 2013 6:56 pm
Location: Edgecomb, Maine

Re: Leaded vs. Unleaded Fuel and winterizing additive

Post by tkhersom » Tue Nov 04, 2014 6:43 am

Lots of good stuff here.

1) The only leaded gas I know of that is fairly accessible is 100LL Avgas. Trouble is you have to tote it. Personally I add Marvel Miracle oil to my gas on every fill up. Don't know if it really does much to replace the lead but old engines seem to like it.

2) Stabilizing Fuel is a bit of a tricky one, based on a lot of opinion. I have been told that "Sta-Bil" brand only extends the life of the fuel for about 30 day. That being said I have used it with success. Make sure you get the aqua colored product for Marine use Ethanol. I tend to like CRC products and have used their stabilizer as well. Around here there are a lot of people who swear by "Star*Tron". On the advice of a friend of mine who owns Finestkind Boat Yard in Harpswell Maine I have started using a product called "Pri-G". Not only does this product stabilize the fuel, but also helps eat away at any "varnish" in the tank. I guess we will see how it works. :wink:

3) As far as winterizing goes I like to run my engines on fresh water for a while to bring them up to temperature and flush the system especially if the boat has been in Salt Water. I have also tried salt eliminator, obviously this is not necessary for a boat that is run in just fresh water. I than drain the system, close it back up and run the engine on pink antifreeze. I was introduced to "Ban Frost 2000" this year by my restorer Mike Mayne at Edgecomb Boat Works. This product not only protects to -100 but also has a lubricant/rust inhibitor. I think I will even replace the antifreeze in my enclosed/freshwater system with this stuff.

All of this takes time, but it sure beats finding a cracked block come spring. :mrgreen:
Troy in ANE - Former President CCABC

1957 CC 21' Continental "Yorktown" (Mom's boat)
https://www.chris-craft.org/boats/22625/
1958 CC 38' Connie "American Beauty"
https://www.chris-craft.org/boats/22607/
1985 Formula 242LS "Gottago"
1991 Formula 36PC "Band Aids"

Life Is Too Short To Own An Ugly Boat

Post Reply

Who is online

Users browsing this forum: No registered users and 4 guests