engine stalls at idle

[smtilford]

I have a 1984 BayLiner CX225 19', it has an AQ225D with a 280 outdrive. I have replaced the starter, alternator, plugs, wires, new electronic distributor, new coil, new relay, new battery, and a rebuilt carb. It starts when I give it full throttle, but when I back it of it dies. I double checked to make sure it was at TDC. I am at a loss on what to try next. Any advice would be greatly appreciated! Thanks! Sean

 

[midcarolina]

It sounds like it is fuel related......... I would pour a little gas in the throat of the carb and see if she fires........If so then you know it's fuel related and can then revisit the carb rebuild, check fuel filters, check fuel pump.

 

[smtilford]

Thanks, Midcarolina! I will give that a try tomorrow and see what happens.

 

[jerryjerry05]

Sounds like the carbs low speed side isn't working.
Turn the air screws in till they just touch.
Then out about 2 turns.
Then adjust from there.
A lot of times these older quads get rebuilt and just don't work well??

 

[Scott Danforth]

I would guess the primary side jets and the idle circuit need some love. time to pull the carb and give it a good cleaning.

 

[smtilford]

I will adjust as recommended. My father-in-law came over today to give me a hand, and we found that when we disconnected the fuel line from the carb no fuel was being pumped. We removed the pump and all lines, and replaced the fuel filter. We cleaned up the pump, and when we disassembled it, we did not see any obvious signs of damage. When we tried to re-install we found that the linkage rod had fallen, and didn't know how to fix. I think I have found the answer, that I need to make a hook out of wire to lift the rod and then put the pump back on. I will try that tomorrow. I am also going to check my vent hose, as that is the only line I did not remove, and I have read that it can become clogged and not allow fuel out of the tank. If I still have no fuel, I am assuming that I need to replace the pump. It is 30 years old, so the diaphragm may not be strong enough anymore. If you can think of anything else I need to check or replace, please let me know! Thank you! This forum is such a vast wealth of knowledge!

 

[midcarolina]

Since you have the pump out and it is 30 years old I would not bother putting that old pump back in......... get a new pump

 

[smtilford]

I am on a budget right now with a 2 month old girl, so I will have to wait at least a couple of weeks to buy a new pump. I am going to install the old to continue to rule out any other issues while I can test in my driveway instead of stranded in the Puget Sound!

 

[smtilford]

Ok,so after installing the fuel pump and cranking the motor for a while, i have determined that the pump is dead. I just ordered a new electric pump and fuel line, i am going to replace the hard fuel lines with marine grade 3/8 fuel hose.

 

[Scott Danforth]

if you run an electric fuel pump, you need to wire in an oil pressure switch and relay.

 

[smtilford]

I was planning on buying a Holley 3 leg oil pressure switch, from what I have been reading tonight, it acts as the relay, connecting the normally closed leg to the starter, the normally open leg to the ignition switch and the common leg to the fuel pump. Does this sound correct?

 

[midcarolina]

Yep..... remember to get a blank off plate and gasket for the mechanical fuel pump opening on block.......

 

[smtilford]

Midcarolina, can you direct me to a link for the block of plate? I cannot find it. But then, I might not be searching correctly.

 

[smtilford]

Nevermind, I just had to phrase it correctly. Found this one http://m.summitracing.com/parts/sum-401030 $3.97!

 

[smtilford]

So, after fixing all the wiring problems, which were numerous, and then new fuel hoses and filter, oil pressure switch, new pump, it started! I got the carb dialed in, and then set the timing to 8° BTDC, she purrs like a kitten! I am going to take her out in the morning! Thank you for all the help, guys!

 

[midcarolina]

That's great glad you got her fixed.............

 

[smtilford]

Well, I thought she was fixed, but the tachometer is all over the place, and when I tried to run WOT, it backfired and surged. I am once again at a loss. Any help would be greatly appreciated!

 

[midcarolina]

The new electronic distributor is it a direct replacement or a upgrade?

 

[smtilford]

It is from a mechanic who replaced his aq225 with a fuel injected motor. The distributor in my boat had points, and was very corroded, so I installed this one.

 

[smtilford]

I still have my old one, and I have a electric conversion kit for it, do you think it would be worth trying to clean up and install it?