I have been adding seafoam and an octane boost to the superunleaded I use and have noticed since then some backfiring when I start it. It will turn over start and then backfire and stall. It will do this once or twice the run smooth the rest of the day and not backfire when I start it again. Its only that 1st start of the day. Any ideas?

Seafoam will cause a motor to run like crap if you use to much

I fix motorcycles as a side business - I don't know why people suggest seafoam - that stuff is garbage for an engine.
I get a dozen cases a summer of guys spraying that crap in their motors and wonder why their engine is running like crap.
Yes it cleans your engine and lines of crap - but it pushes it all somewhere... Mostly it clogs your lines
I don't recommend it
Just My opinion.

Buzz, what do u recommend

Gonna go out on a limb here and say....GASOLINE...maybe?

WOW, awesome

are you adding seafoam every time you fill up? if so, why? i been using seafoam for years but only as needed. myself along with countless of others been using the stuff with no trouble whatsoever. as for the octane booster. personally think that shit is useless.

So I quit adding the seafoam to the gas and the backfiring has stopped. As for the octane additive, my engine would top out wot on plane at 3930rpm.....thats the most it ever went on the water. now, it is running at 4080 wot on plane.....It does work for me at least.

good to hear you gots it figured out.

Fuel octanes are not going to giv you more power due to a higher number... The higher the octane the less it will want to ignite... It is there so you can run Higher compression engines and have a SAFE fuel to run and get the most potential out of the motor.
Your avearge joe blow running super unleaded thinking it gives them a power advantage is crazy.

whatever it does, my boat runs at a minimum 100 rpm's faster than without. Never could brake 4000 untill i started using it.

I've been using Seafoam for years, and swear by it. Let a mower sit for almost over a year, and it started right up. Amazing stuff. I add it to every small engine I own. Followed the recommended mix, and I've never had a problem.

Late response:

I like the aforementioned "gas" answer

I tend to lean towards premium fuel - less ethanol the better

But as far as engine care - you can't go wrong with an ethanol stabilizer added to your fuel ( even low grade)

It cuts down on the build up and can prevent fouling in your lines. I've used it with good results

Seafoam like I said - works for cleaning out your engine of junk - most people use it AFTER they notice bad engine performance
Then it gets cleaned of all the crap that's been building for months or even years and clogs everything up

Get in the habit of adding a good ethanol treatment to your fuel and it'll run like gold for a long long time

Just my 2c

Hope it helps

Oh yeah - not overly familiar with octane booster... So no idea there

After playing with a few tanks and talking to a few mechanics I know, I have decided to keep adding octane boost and only add sea foam to the fuel when i change my oil . Running with and without the octane makes a difference on my engine and with it I can manage at the very least 4100 rpm in windy choppy conditions. I can run 4210 on slick water unloaded except for blind. That being said, my buddies all told me to run an ethynol treatment, which i do already and to add seafoam to the oil every oil change and to gas at that time to help keep from getting build up. So thats what Im gonna do.

So how much are you actually gaining from this extra 100 rpm's with the octane booster?

So how much are you actually gaining from this extra 100 rpm's with the octane booster?

Math says 0.75 mph....

100 rpm / 1.5 to 1 ratio = 66.66 rpm at the prop

12 pitch prop and extra 66.66 rpm after conversion to mph = 0.75 mph
Not allowing for lost efficiency wind speed gravitational pull or planet rotational BS - LOL

That's why I hit my props with an orbital sander between runs and clean it
up a bit - usually adds about 100 rpms too...

Just Curious - what octane boost are you buying there Eljefe ???

There is 2 different kinds I picked up at auto zone, dont remember their names ..... one I think is 108 boost (?)..... the other had dale earnhardts name on it. Both contain lubricants and octane....I notice more pep in the throttle and it seems to push a little harder in the mud, before it bogged down a little with the load at take off now it dosent even hesitate ( unless its got clay in it). I'm hoping with the blind off and just me I can pick up even more.... How many rpm's would i pick up with a carb kit? I know it would get rid of the linkage and make the throttle more responsive but would I see much more of an increase in rpm's?

Also, how much money is 1 mph on a mud motor? meaning if Im running a smooth 27 mph and I wanna do 32mph under the same conditions, how much do I need to spend upgrading? And how much can one do before the motor becomes unreliable or unstable? If I want to maintain reliability and not worry about tearing up the motor using it all the time, and quite frankly abusing it. What is the point at which I shouldnt cross on modding it?

x2

the first couple or three mph gonna cost about 500 bucks a piece,after that,more expensive and less stable lol.

I can blow Shit up!!!! The stock 36 has held up to alot. And as for being scared, I scare myself but breaking down don't scare me it just sucks.