Why does my Looper smoke so bad when cold?

[imq707s]

I've got an 89' OMC GT200 on the back of my Vegas. It seems like ever since I got rid of the VRO unit and when with an electric fuel put and 40:1 gas mix.......it smokes really back when the motor is cold and there is a little load on it (like when I'm idleing out of a no wake zone by the boat ramp).

After I get the boat in the water and fire up the motor, it will idle great and doesn't smoke much at all. But as soon as it's in gear and I'm idleing out of the no-wake zone......it start pukeing ton of thick grey/white smoke. As soon as I get out of the no-wak zone and start to open it up, it stumbles a little.....and then as the boat comes on plane it starts to run line normal. As soon as I have ran it around the lake for a minute to get everything heated up....it will idle around fine with no smoke at all. Even if it sits for a few hours and cools down....it will fire right back up and idle just great.

I'm assuming that that it has something to do with primeing it to get it started when I first put the boat in the water. When I hit the primer for a second.....the electric fuel pump probably pumps way more fuel into the carbs than the VRO ever did. I've tried starting it without priming it.....and it's a real pain.

Any other ideas as to why this thing smokes so bad when it's fired up for the first time in the morning? Is there anything I can do to restrick the amount of fuel that gest dumped into the carbs when I prime it?

Thanks

Thanks

[bigbore]

THE MAIN ONE IS OIL'S GONNA SETTLE AT THE BOTTOM OF YOUR GAS TANK (WHEN PRE-MIXING),the second is gas evaporates n oil does'nt,the 3rd thing about o.m.c. is the recirculating system has got to clean out (when fired):cool:

[pyro]

Gas & oil doesn't settle, it should be dissolved.

[Mark75H]

grey/white is usually steam, oil tends to be blue, over rich fuel more black

[SportJ-US-1]

Actually it's because the VRO ran at about 100:1 at idle and so there was very little smoke. Now you are a 40:1 and there is gonna be a lot of smoke. More oil = more smoke.

[Ted Stryker]

Gas and oil can seperate somewhat under a dead still enviroment over a long time, but any movement whatsoever and it will suspend again 100%... The drive to the lake would be about gazillion times more than it would need to re-mix...

[imq707s]

Thanks for all the replys....

I'm pretty sure ....well actually I'm 100% sure it's not steam....it's smoke from the gas/oil. What I don't understand is that after I get the boat off of the trailer in the water and fire up the motor....it will idle just fine. I can rev it up a bit, blip the gas and the throttle responce is great. But as soon as I get it in gear and start idleing out way from the dock....it start loading up, running really rough, and smoking like a smoke bomb. As soon as I get it up on plane it smooths out and runs fine.

After I run it around a bit.....it will run/idle fine with no problems. I've idled it around the lake for 20min before with no problems like loading up or smoking.

As far as the fuel being fully mixed.....I've got a 1 hour drive to the lake, so it all the bouncing aorund on the trailer....I'm sure the fuel isn't seperating out.


"the 3rd thing about o.m.c. is the recirculating system has got to clean out (when fired)" ....can someone please explain this?

Thanks again

[bigbore]

when at idle (before shutoff),its,still runing unspent gas&oil through the recirculating system (especially with the gas being forced in from a fuel pump)
causing it to load up when shut-off time,its no big deal (its actually a solid idea o.m.c. did for longevity).
basically its feeding it more fuel&oil than it needs and the fuel&OIL stays in the relief valve&lines until restarted.:cool:
thats what causes it not to have dry starts.

[imq707s]

So should I just trying cranking it longer to get it to start instead of hitting the primer a few times?

Can a motor run fine at idle with no load.....but then load up when it's in gear and idleing?

[SportJ-US-1]

So should I just trying cranking it longer to get it to start instead of hitting the primer a few times?

Can a motor run fine at idle with no load.....but then load up when it's in gear and idleing?

No, it's not gonna start without choking when cold.

Yes, because when you are in gear the motor is idling at a slower rpm.

[SportJ-US-1]

So should I just trying cranking it longer to get it to start instead of hitting the primer a few times?

Can a motor run fine at idle with no load.....but then load up when it's in gear and idleing?

Yes, because when you are in gear the motor is idling at a slower rpm.


FYI, the recirc system was EPA inspired to keep excess gas and oil out of the water. Back in the old days the motors just let it go out the exhaust, unburned and slick the water.

[bigbore]

its also a good idea for truer combustion burns but if to much unspent gets sent back through then it won't stay true in its w.o.t. state,THEN ITS ALL ABOUT CARB TUNNING,THATS WERE A GURU LIKE STOKER COMES INTO PLAY,SOMEONE THAT KNOWS LOOPERS LIKE THE BACK OF HIS HAND,THERES OTHERS BUT THERES MASTERS TO,THE THINGS THAT GUY CAN DO WITH A LOOPER IS UNBELEIVABLE:eek: SEND IT TO HIM,HE'D PUT REEDS IN AND TUNE IT FOR AROUND THE VISCINITY OF A GRAND,IM TELLING YA YOU CAN PLAY WITH THESE LOOPERS (TRYING TO TUNE)FOR DAYS AND STILL HAVE 1 OR MORE CYLINDERS OFF,HE'D TUNE IT FOR THE FUEL PUMP TO.:cool:

[pyro]

Oil and fuel in the bleed/recirc lines, and particularly anything that's puddled up in the crankcase, tends to concentrate the oil as the volatile fuel evaporates, leaving the motor nicely oiled. As you start up and idle, the fresh fuel washes the extra oil into the cylinders, giving you the fresh start smoke.

"Loading up" while idling is the same concept, except there's not as much excessive oil, just general excessive fuel/oil puddling in the motor that burns off as you get on the throttle again.

[imq707s]

So basically it sounds like you guy are saying that it's normal and I just need to deal with it? :D

[Jay R.]

also don't rule out grey white smoke as unburnt fuel from not being warmed up yet.

[SportJ-US-1]

So basically it sounds like you guy are saying that it's normal and I just need to deal with it? :D

Pretty much, as it is the nature of the beast without VRO and I never trusted the VRO system. I mean they changed it over 100 times in a couple of years. Do you see a pattern here.

[B.Mac]

[QUOTE=bigbore]THE MAIN ONE IS OIL'S GONNA SETTLE AT THE BOTTOM OF YOUR GAS TANK (WHEN PRE-MIXING)
You just jumped from 75/1 to 40/1......Don worry be happy........Open throttle and she clears out....

Don worry, 'bout it. Jus' go fast and make that Vegas stand up on the pad......oil is good......
B.MAC:D

[SportJ-US-1]

[QUOTE=bigbore]THE MAIN ONE IS OIL'S GONNA SETTLE AT THE BOTTOM OF YOUR GAS TANK (WHEN PRE-MIXING)

Don worry, 'bout it. Jus' go fast and make that Vegas stand up on the pad......
B.MAC:D

This statement is about as wrong as it can get. By the time you have towed to the ramp the gas and oil will be as mixed as if you just shook the tank. Where do you guys get this info? The oil and gas have to sit very still for a long time for there to be any seperating and if the liquids move at all they recombine. The oil is formulated to stay in the gas. back in the 50s and 60s this was a problem but not anymore.

[B.Mac]

Smoke.....
If you don't burn your fuel every time out (empty the tank) When you drop it in again it's gonna smoke until you get enough violence (shaking) to mix it up.
OMC's smoke more naturally anyway 'cause they got more sense than a Merc. Kinda like the joke about the old bull and the young one lookin' over the heffers......:D As long as i's smokin' don't worry.......be happy.......
B.MAC:D

[bigbore]

[QUOTE=B.Mac]

This statement is about as wrong as it can get. By the time you have towed to the ramp the gas and oil will be as mixed as if you just shook the tank. Where do you guys get this info? The oil and gas have to sit very still for a long time for there to be any seperating and if the liquids move at all they recombine. The oil is formulated to stay in the gas. back in the 50s and 60s this was a problem but not anymore.
yea,if he has to tow it to use it,then NO DOUBT theres nothing to worry about,if it sits on the trailer or BOAT LIFT (is what i was thinking cause of the lake usage)then the oil could seperate n settle,but yea if it gets towed at all theres no worries.:cool:

[H2OPERF]

Its gonna smoke at 40/1 but u may be able to make it somewhat better by fine tuning the jetting and idle timing.The motors are jetted from the factory abit rich so they will run in most any environment (cold, high alt, ect.)without too much lean sneezing and quitting when first started.If yours doesnt sneeze at ilde when u first start u may be able to go abit leaner on the idle jets,also the more u advance the idle timing(to speed up the idle) the richer it will get,often u can increase the jet size on the idle circuit instead of advancing the timing to speed up the idle depending on alt/climate,and not allways on all cylinders.Dvae

[RIVERRUMMER 70]

I Have Had Some Success With Making Sure The Motor Is Trimmed Level To + Trim Angle When Idling My Non-vro V-4 Looper!
This Has Some Effect On The Carb Downdraft Into The Manifold.
Tucking The Motor Under Will Cause My V-4 To Load Up Bigtime!!!
But When I Stand On It It Takes 15 Seconds To Clear Out.
Been Runnin Vro Free For 10 Years, 87 Commercial V-4 140 32:1 @6500
Rock On Dude!!!!!

[imq707s]

Thanks again for the help guys.........

But if you look at my original post, the motor only smokes when I first fire it up after I get the boat off of the trailer. Once I run it for a few minutes down the lake, it runs fine. Even if I let the boat sit in the water for 6+ hours......it will fire up fine and idle great.

It seems like I only have problems when the boat's been sitting in the garage on the trailer for a week or more. Could the fuel in the carb bowls be leaking into the motor somehow when it's sitting for a long time?

Thanks again.

[lokinutz]

I read a thread about this a year or so ago and remember racer saying that when your boat has sat for a period of time, the fuel in the motor will evaporate, leaving the oil still in the motor, causing a smokey condition until the motor has been run enough to clean the excess oil out. I would imagine your boat doesn't smoke in neutral because there isn't enough load on the motor to force the excess oil through the combustion chamber. I bet if you start it on the trailer it doesn't smoke at all, but as soon as you rev it good once or twice it will smoke like a banshee until you get it on plane and clear it out. That's what mine does. One question...does it only do it your first start of the day and then not the rest? Would say it's the reason above.

[imq707s]

Yep....it only does it after it's been sitting for a few days and I first start it in the morning. If I run it in the morning and the boat sits for a few hours....it will fire back up and not smoke a bit.

That sounds like a good explination....the gas is evaporating after sitting for a few days.....then there is excess oil left in the motor. I'll have to try revving the motor some more before I idle away from the dock....maybe that will clean it out some.

Thanks.

[lokinutz]

Unfortunately, revving the motor more on the trailer will just make it smoke more. (Although you could always try it and see what happens) You need the load and heat of being on plane to clear the oil. Just keep doing what you are doing and have fun.

[imq707s]

Got to love that smokey 40:1mix.

Would running fully synthetic old cut down on the "start up" smoke at all?

[Over-Easy]

What trim angle is it at? That has alot to do with the way they run at idle. If you've got it trimmed high all the way to the bouy it will pool fuel and oil. waiting for the angle to come down or the engine velocity to pick up, pulling the excess fuel into the engine.

[imq707s]

I usually trim it up pretty high....usually level with the water or higher . If I tuck it in....it really smokes bad! It idles better with the Bobs exhaust snout just sticking a little out of the water....sounds better that was also :D

[Wolverine]

Got to love that smokey 40:1mix.

Would running fully synthetic old cut down on the "start up" smoke at all?
It'll still smoke at start up with synthetic. I've been running 50:1 in my drag motors for over 10 years ( at the recommendation of my engine builder) with no oil related problems.
I talked to David Pou about this awhile back. He twists his high dollar Diamond Marine motor over 11,000 rpm's using Klotz at 50:1 . That's good enough for me.
But......even at 50:1....... it'll still smoke when it's cold.:)

[Lockjaw]

When I got my looper and put it on my boat, it didn't have oil injection connected, since my flow was pre-mix. It smoked pretty good at idle, even after it was warmed up and idling.

Once you got out on the water and ran the engine and warmed it up, it didn't smoke as much. Revving it up in idle made it smoke way worse.

I found synthetic (Penzoil) smoked worse then the XD-25 omc oil. I have since reconnected the oil injection, and it smokes very little. The oil injection was actually pretty reliable, its just alot of things got blamed on it that were not its fault.

[lokinutz]

I also run Pensoil synthetic at 50:1 and it smokes pretty good too, I think more than blend oils. The best way to keep your carbureted looper from smoking is to keep it on the trailer!!!

[bigbore]

its carburated so running 100% synthetic is not nescesary,or not wanted (i've been told more than once).
also i should be idleing (in gear)around 700 r.p.m. or a little better (if it starts sneezing and dieing)you can play with the idle-air if it doesn't idle right(in gear)also,you'll get her,and it's gonna smoke some.:cool:

[imq707s]

Well I had the boat out this weekend and it seems like the smokey idle problem is getting worse. I put a fresh set of NGK's in it, but that didn't help. Once it's up and on plane it's fine.....but any idleing and it smokes and starts to load up. It never did that last year (even with the 40:1), but it seems like this summer it's doing it all the time. Even after I run it around for a while, as soon as it idles around for over 3-4 minutes....it starts smoking and loading up.

Could the idle bleed jets on one or more of the carbs be clogged? Also...I've heard some people mention the recirculation system on OMC's....can someone explain that? I guess there are some check valves that need to be cleaned every once in a while??

Any help would be great......I'm getting tired of this Looper puffing out smoke all the time.

[baja200merk]

my loopa'z jetted rich for breakin but when i replaced my recirculation valves and cleaned the lines it idled 200rpm lower with out stalling... somthin ta think about...
id think the smokey start up has alot to do with left over oil, but if ur sayin it does it after runnin id think ur idles are rich... but im no pro just somtin ta look into!
kevin

[imq707s]

Can someone give me some info and maybe post some pics of the recirculation valves and the lines?

[ezeke]

I respectfully disagree on the "live with it".
The pre-mix fuel ratio for the looper is 50:1, and the recirculation check valves beg for periodic replacement.

[imq707s]

OK......you guys keep talking about check valves and the recirc system.....but can someone PLEASE tell me were the checkvalves are located??? I looked all over my motor and all I can find is a 1/2" hose that runs from the top of the motor to the bottom of the motor....and near the bottom there is a T fitting with an arrow on it that I'm assuming is a checkvalve. It's pointing towards the top of the motor....and the line that is T'd off is running into the airbox for the carbs. Is that the entire recirculation system?? One hose from the top of the motor to the bottom of the motor with a T/ check valve in it?

Can someone please give me some more info on the recirc system.....what it does, what it's there for, what it looks like.......how many check valves (1,2,3)??

What am I looking for here?

Thanks again.

[bigbore]

coming from the side of the cylinder to the intake manifold,they are 1\2 in. vent lines,what they are connected to (on the cylinders)is the releif valves.
on the intake-manifold is just fittings.
replaceing them is a good idea,its not to spendy,and its possible they have carbon in them causing cloging which could lead to unsteady idle and running through out the entire rpm band.syncronize syncronize syncronice,thats key when trying to make all 6 perform in tune.from thorottle linkage to releif valves to carb tuning,they need to sing together.:cool: