Volvo AQ171a will not stay running. Please Help!!!!

[tompowers85]

I have an AQ171a that will not staying running. I had the entire rebuilt cylinders bored, new rings, pistons and rebuilt the carbs. I also replaced the mechanical fuel pump and put in an inline electric fuel pump. I am getting plenty of fuel at the carbs and when I pump the throttle it spays fuel into the engine. If I do that a few times the engine will run for about a minute but then stall. If I pump the throttle a few times it will start again. It usually backfires through the carbs when it stalls. I cannot figure out the issue. Can anyone please help me with the issue?

 

[Don S]

Re: Volvo AQ171a will not stay running. Please Help!!!!

Sounds like you may need some timing, and carb mixture adjustment, after you get the engine warmed up and the choke off.
It takes a bit of adjustment to get a newly rebuilt engine running right.

 

[tompowers85]

Re: Volvo AQ171a will not stay running. Please Help!!!!

The timing for the engine is all electric. The choke is electric and it has some hoses that I tried to hook up but the one hose will not reach the back carb. I also cannot get find the correct wire to connect to the choke.

 

[Don S]

Re: Volvo AQ171a will not stay running. Please Help!!!!

Disregard, AQ171A, I was thinking AQ271, Which is a Chevy V8

 

[Don S]

Re: Volvo AQ171a will not stay running. Please Help!!!!

Ok, AQ171 now. You still have to set the the static timing with a timing light, even with the electronic (Renix) ignition.
You may also have to re adjust the carbs, and sync them after the rebuild. The manual gives you preliminary adjustments only, final adjustment must be made to work properly.
You also need to make sure the "restrictor plates" are installed under the carbs properly.

Here is a link to download the OEM manual (Free) in case you don't have one. http://www.4shared.com/file/64741910/25295432/230_250_251_131151171.html

 

[tompowers85]

Re: Volvo AQ171a will not stay running. Please Help!!!!

Looking at the manual I downloaded I did put the restrictor plate on the front the wrong way. The book I bought really sucks. Could this be an issue with the coil? I have great spark but reading some forums it sounds like this could aslo be the problem.

 

[Don S]

Re: Volvo AQ171a will not stay running. Please Help!!!!

I would sure fix the restrictor plates first. If you have good spark, there is no reason to replace a coil just because you "read it somewhere"

 

[tompowers85]

Re: Volvo AQ171a will not stay running. Please Help!!!!

I fixed the restrictor plate and I also found that the vacuum hoses were switched. I have also tested compression and everything is great, but it sill only runs for a few seconds and then stalls out.

 

[Don S]

Re: Volvo AQ171a will not stay running. Please Help!!!!

Are you working with the carb to keep it running? Those engines do not have chokes and may take some work to keep running, even when all set up. Since you haven't had it running to set dwell, timing, and adjust the carbs, it may take some work an rpm to keep it running until it warms up.

 

[tompowers85]

Re: Volvo AQ171a will not stay running. Please Help!!!!

I can get it running buy filling the carb with the accelerator pump and then run back and start adjusting the idle, but it takes a lot of work and then no matter what I do it stalls. I can hear the carbs sucking air and see the fuel flowing into the intake manifold. When the engine stalls I can also see fuel down in the intake manifold. I checked the floats for saturation and they are proper weight. When I pulled the plugs I noticed they were black and dry.

 

[Don S]

Re: Volvo AQ171a will not stay running. Please Help!!!!

Does it restart right away?

 

[tompowers85]

Re: Volvo AQ171a will not stay running. Please Help!!!!

if I pump fuel in using the accelerator pump it may take a second but sometimes it may take few tries. I usually have to pump it again to get fuel in manifold to get it running once it stalls.

 

[Don S]

Re: Volvo AQ171a will not stay running. Please Help!!!!

Like I said earlier, no choke and they can take some work to keep running until you get it warmed up and adjusted.

 

[tompowers85]

Re: Volvo AQ171a will not stay running. Please Help!!!!

Do I need to worry about the RPM's getting too high? I am just running it on muffs and I do not want to damage anything.

 

[Don S]

Re: Volvo AQ171a will not stay running. Please Help!!!!

If you stay under 2000, you will be fine. keep it around 1500 if possible.

 

[tompowers85]

Re: Volvo AQ171a will not stay running. Please Help!!!!

If I cover the top of the rear carb with my hand the engine revs up and stays running without me pumping the throttle. Does this mean I have a vacuum leak at the rear carb. When I just cover the front carb I really do not notice a difference.

 

[tompowers85]

Re: Volvo AQ171a will not stay running. Please Help!!!!

I have gone through the fuel system and made sure everything is tight and no difference. I can still keep it running if I cover the back carb with my hand, but it will also work if I cover the front carb with my hand. The spark plugs are black and dry but it seems like I am just not getting enough fuel into the engine.

 

[tompowers85]

Re: Volvo AQ171a will not stay running. Please Help!!!!

From reading several posts I have decided that I have a vacuum leak, but I do not know how to explain the extra fuel that is still in the intake manifold. It seems like it is not getting enough fuel but it still has plenty in the intake manifold, but I did order a vacuum gauge to test the vacuum for my engine. I hope that will tell me a little more.

 

[captmello]

Re: Volvo AQ171a will not stay running. Please Help!!!!

so you're sure you have your air/fuel mixture screw set to the proper preliminary setting? there are two settings for early and late model versions. 2 revolutions out for the early models and 10 revolutions for the late model.

by putting your hand over the carb, you're basically choking the carb manually. Like Don said, there are no chokes on those carbs so they can be tricky sometimes until they warm up. Can you keep it running long enough to get a timing light on there and see where the timing is @ 10 dtdc @ 900?

 

[jason niswonger]

Re: Volvo AQ171a will not stay running. Please Help!!!!

I just started to work on my 171A and I have the same problem, I think it has to do with getting both carbs set just right. I will let you know my progress. I need to buy new spark plugs, what spark plugs did you buy for your 171A?