Is this a carb problem?

[smithrock]

'85 Mercruiser Alpha 1 Gen 1

the boat will idle and cruise through the marina at 5mph no problem but when I try to go to WOT it bogs down and stalls! Then it takes several tries to get it restarted? Any ideas on what's going on there?

 

[Don S]

Re: Is this a carb problem?

It could be.

 

[smithrock]

Re: Is this a carb problem?

It could be.

Anything else it could be, or is that the first place i should look? I don't think the secondaries are opening up. I have an Edelbrock on there.

 

[tkmichael11]

Re: Is this a carb problem?

I just went through the exact same problem. It turned out to be the carb. I replaced it and havent had a problem since. The one piece of advice that I got was to borrow one that you know is good and try it. You can also find used ones on craigslist.com or ebay for next to nothing. I got my new one through www.i-5automotive.com The carb was about $200 and the customer service over there seemed to be pretty good. PM me and let me know how you make out.

 

[jtybt]

Re: Is this a carb problem?

Why buy a carb if the problem is somewhere else.

Sounds like fuel flow problem but there is a procedure.

The easiest thing to do if an engine dies is go back and remove the flame arrestor and pump the throttle as you look down the primary bore of the carb to see if the accelerator pump is squirting gas. If not, that could indicate gas flow to the float bowl is restricted or a float valve is stuck closed and it's running out of gas. If it is squirting gas, it could mean the float valve is stuck open and it's getting too much gas.

Report back what you see and you will be advised what and where to check or do next.

 

[tkmichael11]

Re: Is this a carb problem?

My suggestion was to borrow a carb that works and try it first. If that solves the problem, than the problem is the carb. The easiest thing after that would be a replacement. Hence the suggestion to buy a carb.

 

[jtybt]

Re: Is this a carb problem?

Also pull the fuel/water separator end empty into a glass jar to see what comes out. There is also a little filter in the carb fuel inlet.

 

[smithrock]

Re: Is this a carb problem?

Also pull the fuel/water separator end empty into a glass jar to see what comes out. There is also a little filter in the carb fuel inlet.

Will do, I'll check it tomorrow. I did however, remove the flame arrestor yesterday and checked the throttle. it does rev up but the secondaries weren't opening. I think they open under load though. I do see fuel squirting into the front 2

 

[jtybt]

Re: Is this a carb problem?

You have to check the accelerator pump right after it quits.

Another check is the fuel pump flow. when you disconnect the fuel inlet to the carb. have someone turn the engine over for just a bit to see the volume of gas being pumped. Be careful and get a coffee can the catch the gas. Ground out the coil wire. Be careful.

The upper secondaries(trap doors) of the Q-jet only open under load.

 

[Gene70]

Re: Is this a carb problem?

tkmichae/11 stated in a post that he got a carb online at i-5automotive. I hope it is a marine carb. They carry marine but you have to ask for it. It is very dangerous to install an automotive carb and a $5000 fine if marine police or coast guard catches you. An automotive carb floods on intake manifold. A marine carb floods and dumps internally.

 

[snoski]

Re: Is this a carb problem?

Why buy a new carb when the Rochester is simple to rebuild????

 

[snoski]

Re: Is this a carb problem?

Sorry, but Edelbrock can also be easily rebuilt...

 

[smithrock]

Re: Is this a carb problem?

I took apart the carb and cleand it, it looked fine. nothing gummed up or blocked. However the floats were stuck closed! Could that cause my problem of bogging and stalling when trying to go to WOT?

also, checked the water/fuel separator, it was fine.

 

[180shabah]

Re: Is this a carb problem?

However the floats were stuck closed! Could that cause my problem

Absolutely!

Buy a rebuild kit, soak the carb, blow it out, reassemble, go have a great day on the lake.

Unless, you still also need filters and a tune up. Now would be a good time.

 

[smithrock]

Re: Is this a carb problem?

Absolutely!

Buy a rebuild kit, soak the carb, blow it out, reassemble, go have a great day on the lake.

Unless, you still also need filters and a tune up. Now would be a good time.

I sure hope thats all it was! I took everything apart, jets, filters cleaned and blew out everything. It all looked good except for the floats stuck in the closed position!

Now if I could just get my shift cable adjusted correctly I installed a new one but I'm having trouble getting it to be just right. I have the manual and have followed it. I think my upper cable (remote control) is adjusted right?