AQ225 idles good, dies with some throttle

[86Capri]

Hello all,

I have a 1986 AQ225D, with a quadrajet I just purchased re-manufactured off ebay. I just replaced the fuel filter, fuel pump, starter, and alternator. I have set the timing to 8* and triple checked it multiple times. It starts and idles great! But if I give it any gas, it falls on it's face and dies. IF I hold the choke almost closed, it allows me to rev it up just fine. I get about 15 vac using the nipple that would be going to the little metal vac puller thing. I have gotten it all the way warm, letting it idle for over 10 minutes in a bucket of water, I'm glad the water pump works good. I did have a vac leak on the bottom right "port" where the electric choke would be, but plugged it with some tape. Same issue. I have used a tube up to my ear to find any other hisses or leaks, and I can not find any. I am starting to think there is something wrong with the carb, possible incorrect jets? It is a 305, if he put in 350 jets, would that cause a problem like this?

Thank you.

 

[Maclin]

Sounds like the accelerator pump linkage is not hooked up or is way out of adjustment. With engine off, and the flame arrestor removed, look down the primary bore and move the throttle, may need to hold the choke plate open. When the throttle is moved there should be 2 strong streams of fuel squirted into the primary bores, speed and density proportional to the throttle movement. If none are seen or heard, or the stream is not strong or only a dribble then the carb neeeds looked at.

 

[86Capri]

Thank you for the idea, but the accelerator pump is working perfectly as it should. I can see it squirt, and if I hit the throttle hard it will rev up for a second, then die down. Also, if while it is stalling from having a little bit of throttle, I can hit the accelerator pump and it stays alive. I am confident that they are working.

Thanks again.

Also, when I say I am giving it gas, I don't mean a quick blip. I can crack the throttle just barely, and it will stumble and die.

 

[Maclin]

Fuel should come out of the squirters any time the throttle is moved. If there is some play in the accel pump linkage then it may not hit the squirters soon enough. You seem knowledgeable about the accel pump so nuff on that. Now it sounds like a lean/clogged idle circuit, causing a problem with transmission to the main jets.

 

[Maclin]

I think it should rev even with too small of main jets, but not if they are already clogged. Have you had the top off and looked around for foreign material?

 

[86Capri]

I can agree with that. It was supposed to be a new unit right from i5 carbs, but I guess I have to uninstall it and take it apart to see. How much of the throttle does the idle circuit get used in? When do the main jets kick in? Thanks.

 

[86Capri]

I just went out and did some more testing before I take it off and give up. I put my hand over the primaries, and was able to get to rev and run pretty good. I could physically feel the cool fuel hitting my hand though. I then loosened the e-choke and closed it just the perfect amount, and it was able run and rev perfectly. I manually flicked the secondaries and the tach shot up super quick, very responsive. I really think these primary jets or something to do with the primaries is causing a very lean condition.

Can I get one more confirmation before I open up a freshly rebuild carb?

Also, I have my original old carb that came with the engine that was just completely junked up. I just took the jets out of it, but I don't see any numbers or marking on it. Is there any way to tell what size it is? Any harm in cleaning them out and swapping them into my new carb? Do I have to have the corisponding rods? One of the rods was bent in my original carb.

 

[no704]

1st make sure your dizzy advance is on the top end of the carb, not full manifold vac. 2nd get a can of starting fluid, in a well ventated area, and spray around gaskets n carb. If you hit a vac leak rpms will go up. Good luck.

 

[Maclin]

Yeah, vacuum leak testing is needed. Way too lean in the primary flow right now.