Sea Foam in an older I/B

[airman]

I have a pair of 1972 Chrysler 400's with 1960hrs on them, mostly at less than 1700rpm. They're getting a little weak and won't push past 3300rpm anymore and they tend to wander a little, both at idle speeds and moderate power settings. I've played around with timing, carbs etc but mostly they're just old. Compression isn't bad, about 125-135psi all around which is within manual specs. I was noticing lots of guys ranting about Sea Foam, but only in the O/B forums. Has anybody used this stuff in their 4-strokes? Has anyone ever had problems because of it? Reading Sea Foam's site, it looks like the best way to use it is to pour some in the oil, run around like an idiot for a 1/2hr or so and then tie up and watch other idiots at the launch ramp for a couple of hours to let it work. Then I'll drive in circles for another 10min to work it all around and change the dirty oil out. A little shot down the carbs and in the tank maybe. Generally I've been pretty shy about "miracle additives" for engines. My main concern here isn't with wasting a few bucks and an afternoon. That's boating, isn't it? I want to know if anyone has had troubles because of it. Thanks

 

[DJ]

Re: Sea Foam in an older I/B

airman,<br /><br />I've never used it in a 4 cycle crankcase. The only reason for doing so would be for a severely sludged engine. I doubt yours are.<br /><br />However, dumping some in your fuel certainly won't hurt. It may help break up some of the deposits on the back sides of your intake valves and piston tops.

 

[clanton]

Re: Sea Foam in an older I/B

Buy the pint can(not the spray can), use vacumm port to pull fluid into engine, then some in fuel tank, instructions on can.

 

[Lark40]

Re: Sea Foam in an older I/B

Pour it right into the carb, according to the instructions. It will create an incredible amount of smoke. But, it will sure clean out the carbon.<br /><br />Have used it in both cars and 4-cycle boats. Great stuff.

 

[airman]

Re: Sea Foam in an older I/B

I'm not that interested in putting it down the carbs as they're both fairly recently o/h'd and I can't see what it would clean, except maybe the intake valves a bit. In a 2-stroke, that's different because the fuel goes right into the crankcase. Sea Foam talks about putting it in the oil (4-strokes) on their website and that seems the only way to get at the carbon/sludge in the rings, valve guides etc. If I've got some, I'll throw a little in the carbs anyways but it's mostly the oil I'm interested in. Any experience here?

 

[Northern Eclipse]

Re: Sea Foam in an older I/B

Airman for those old motors thats pretty good compression...I would say they could use new timing chains and gears, thats a fairly cheap repair and can breath alot of new life to old motors as long as all else is good, these old cryslers are iron horses for sure, but they where hard on timimg chains, at least in the automotive world anyway, also you state that most of the running has been low rpms, they may not be revving up due to seized centrifugal advance in the distributers.

 

[DJ]

Re: Sea Foam in an older I/B

Airman,<br /><br />Northern Eclipse is dead on correct about his assesment of old Chyslers. Both the chains and the dist. advances were areas of concern.<br /><br />SeaFoam in your newly rebuilt carbs will not hurt a thing. That's the only way you are going to get at the carbon build ups. Putting in the oil will do NOTHING for you except dilute the oil. It won't get to your valves (cylinder side)and it will have little or no effect on getting to the top piston rings.<br /><br />As mentioned, if you siphon it out of the can on a manifold vacuum port, you will completely bypass the carbs. Even if you dump it down the carb throats, it will not get into the float bowls.<br /><br />Make it easy on yourself, dump some in the fuel and go for a ride.

 

[airman]

Re: Sea Foam in an older I/B

Thanks for the replies. Yes, my dist. advance was shot. Noticed that a while back, what I did was rev the engines to 2800 rpm and time them to 22 degrees (or so, I did the math to figure out what it should be). I suppose the power curve isn't what it was designed to be but they ran much better. It was looking like too much trouble/$ to find someone who could supply me with counterrotating marine distributors for those old engines so that was my solution. I'm not unhappy with my performance (18kt cruise, happy engines at 2800rpm) but everyone seemed so impressed with the Sea Foam I thought it would be worth trying. Anyways it looks like it doesn't matter. I was just looking in the General section and found a post (posted today - I did do a search before posting!) that said SF isn't available in Canada. We have UAP/NAPA, I just assumed they'd have it. Thanks anyways, I guess.

 

[Trent]

Re: Sea Foam in an older I/B

I use Berryman's B12 from WalMart or Napa.It works well and is normally cheaper.

 

[bomar76]

Re: Sea Foam in an older I/B

Ditto on the Berrymans B12!<br />That stuff will eat up any kind of gunk.<br />I poured in 6 cans (big tank), took the boat for a ride on the trailer to mix thoroughly then stopped and topped of the tank. <br />Put the muffs on and fired it up. After a few minutes of idle you should have seen all the crap that came out the exhaust. Let it run a few minutes more and shut it down. I changed the fuel filter and cut it open....(this was after I had changed it several engine hours prior)...full of crud from the tank B12 had dissolved. We ran out most of that tank on the water before refilling to get the full benefit. <br />I have also used the B12 carb spray-it it works tons better than the other brands.

 

[airman]

Re: Sea Foam in an older I/B

Phoned Walmart and NAPA. No Berryman's either. I'm moving to the States. Really I am, next spring, but not just for the Sea Foam.