New to forum......first question

[91Astro]

Hi all....I'm new to this forum and still somewhat new to boating. I recently bought a 91 ASTRO 18 FSX and had the Mariner 150 V6 rebuilt (the oil injection failed and the cylinders were trashed. I had the oil injection system disabled and now mix my fuel ....never to worry again!). The boat has run great for the last year but now stalls out sometimes when I accelerate--when it gets going, it runs great. I think I'm going to rebuild the fuel pump myself.....does this sound sensible? Should I run some kind of injection cleaner in the fuel? Any ideas would be most helpful.

Thanks in advance!
Dan

 

[Texasmark]

Stumbling upon acceleration is inadequate fuel from the low speed circuits. You didn't say if your engine was carbureted or not. If it is, open the low speed jets (the only ones you can tweak) about 1/8 turn at a time until it will take throttle and not hesitate. If you get out to 1 3/4 turn area and still no help, might check compression and timing and if ok, might get yourself a ported prop or port yours. Unloads the engine in the hole shot for a faster shot and disappears at higher speeds.

When I joined this forum in 2004 I was introduced to Sea Foam by comments from some senior folks here that were competent OB mechanics and experimenters....racers. I got some and was never without it. Some folks ridicule products such as this but that's their business, not mine. Get some and use it per can instructions. Go ahead and do your 1:50 pre mix ratio but just add this as icing on the cake.

On the fuel pump, if it weren't working you wouldn't be making the "--when it gets going, it runs great." comment. If in doubt but really unnecessary, squeeze the bulb when you think the pump is failing you. If it is and you squeeze the bulb (do the fuel pumping job for the pump) and the engine immediately recovers, then go after your pump.

Mark

 

[91Astro]

Mark,

Thanks so much for the feedback! Sorry I didn't mention this OB is carbuerated. I will definitely try the Sea Foam...I will also look into the low speed jet adjustment--this is not something I've done before! Down the road some I'll try and get smarter about props too. Currently, I'm running a SS Quick Silver Laser II.

Thanks again for your help!
Dan

 

[Faztbullet]

Depending on year of engine it may or may not have mixture screws, if it does it will have plastic caps on them,,DO NOT REMOVETHESE!!! Turn CCW to richen and its possible your has the accelerator pumps on the sides of them and if weak they will cause bogging problems

 

[gm280]

One issue you may think about is that fact that being carbed engine, you will have three carbs to adjust and not just one... So don't adjust one carb and try and keep adjusting just that one carb.

 

[91Astro]

Lots to learn obviously for me...thanks all for the fast replies!! I will be doing a lot googling on carbs! Just a follow up....I have 6 carbs....

Thanks again!
Dan

 

[91Astro]

Xxx

 

[91Astro]

Well, after a lot of reading, I've decided to do the easy stuff first. I bought some Seafoam motor treatment and some Deep Creep as well. I went through 3 cycles of running the motor with treatment & spraying the carbs with Deep Creep (at idle in the drive way wit muffs). Each cycle consisted of 15 min running the treatment out of a 2 gal external tank and spraying the 6 carbs, then 15 min off. The hope here is that the injectors were cleaned and the carbs decarbed. I made a lot of white smoke for sure! One thing I noticed after the 2nd cycle was that my motor didn't seem to shake and vibrate as much.....seems to run smoother/better at idle now. Really won't know anything until we take out tomorrow.....I'll post results tomorow night.

 

[Texasmark]

Well, after a lot of reading, I've decided to do the easy stuff first. I bought some Seafoam motor treatment and some Deep Creep as well. I went through 3 cycles of running the motor with treatment & spraying the carbs with Deep Creep (at idle in the drive way wit muffs). Each cycle consisted of 15 min running the treatment out of a 2 gal external tank and spraying the 6 carbs, then 15 min off. The hope here is that the injectors were cleaned and the carbs decarbed. I made a lot of white smoke for sure! One thing I noticed after the 2nd cycle was that my motor didn't seem to shake and vibrate as much.....seems to run smoother/better at idle now. Really won't know anything until we take out tomorrow.....I'll post results tomorow night.

Smart move! Would have done that myself........"don't fix it if it ain't broke". Too many smart, experienced people recommending SF on here for it to be nothing burt Snake Oil!!!!!!!!!!!!!!!!!........plus my own experience with it being a plus.

 

[91Astro]

Well, we got the boat out today. We eneded up going to a local lake that has a 10 mph speed limit though. The engine started first time every time, and idles and run much smoother. Upon acceleration (to 10 mph!), the motor responded very well. I am confident that decarbing the motor has helped immensely, but still need to run it harder to be sure.

 

[Texasmark]

Well, we got the boat out today. We eneded up going to a local lake that has a 10 mph speed limit though. The engine started first time every time, and idles and run much smoother. Upon acceleration (to 10 mph!), the motor responded very well. I am confident that decarbing the motor has helped immensely, but still need to run it harder to be sure.

Did you "goose it" a couple of times within the 10 mph limit? How'd it go? If it took the goose, ready for more, you should be good to go. Keep the "Snake Oil" in the tank on future fillups.

 

[91Astro]

I did goose it a few times and it took it! Cant wait to run it somewhere else to enjoy the goose!

Thanks....

 

[91Astro]

Well, I finally got the boat out all day yesterday on a lake I could let fly on. After running SF through it and decarbing, it starts easily and run very smooth. However, when I try to go from idle to plane, the motor bogs down when I accelerate.....I have to baby it until it "takes". Then, when it goes, it really goes and runs fantastic! Any ideas on the bogging down? Scratching my head and frusrated...

Thanks!
Dan

 

[91Astro]

Bump