1984 Volvo Runs Rich!

[zvolv]

I am working on my buddies 1984 Bayliner with a Volvo AQ130? engine. Its the 4 cyl with a single carb. 270 outdrive.

They just bought the boat and it only went 6mph. We fired it up on the shore and found out only cyls 1 and 3 were firing. I found this out by pulling plug wires one at a time and noticing no change when wires 2 and 4 were pulled.

Pulled the plugs and 2 and 4 were completely fouled. Black. I put in a new set of 4 plugs and the boat fired right up and we had fun for about 30 minutes and the engine was running great. Then it started backfiring and missing when up on a plane at higher rpms.

Got back to the dock barely. Engine was barely alive. Pulled the plugs and they were all fouled black and number 2 was wet with what I still cant tell if it was fuel or oil. There was also excessive smoke coming out the prop when flushing it.

The carburetor doesnt appear to be original.The previous owner also made a comment along those lines too. Its a 2 barrel and it says made in spain.

So do you think its the carb, or can a weak ignition cause the plugs to go black? I can see a decent puddle of fuel down in the carb with the throttle open. Does one barrel feed cyls 1 and 3 and the others 2 and 4?

What might the problem be?? How would you go about diagnosing it?

 

[Haut Medoc]

Re: 1984 Volvo Runs Rich!

Welcome to iboats.........
I'm not familiar with the older Volvo engines, but there are some here that are, so stick around......
You might want to post the engine serial # for better ID........
Did you ever do a full tune up?......
Points, wires, cap & timing as well as the new plugs you put on?.......
Are you sure you have the wires in the right order?....

 

[zvolv]

Re: 1984 Volvo Runs Rich!

I am new to the forum, but not new to boats or mechanics. I am an automotive Volvo nut but they run EFI and electronic ignition.

I am thinking a carb rebuild might be in order.

Is there any way the points in the distributor could be causing this problem?

 

[Don S]

Re: 1984 Volvo Runs Rich!

Sure the points could do it, the cap, rotor, condenser, bad wires, as mentioned, do a full tuneup and a compression check. If the compression is bad, all the new parts in the word won't help.

 

[zvolv]

Re: 1984 Volvo Runs Rich!

I have established that the carburetor isnt the original for the engine. It is supposed to have the Solex single barrel, but it has some double barrel made in Spain.

The boat was just serviced by a professional shop and the headgasket was just done and the cap says changed 11/07. I will pull the cap and see if there is anything wrong inside.

I am awful at dealing with points. Any tips there?

So black plugs can also mean weak ignition?

 

[ccmarsh]

Re: 1984 Volvo Runs Rich!

I put in a new set of 4 plugs and the boat fired right up and we had fun for about 30 minutes and the engine was running great. Then it started backfiring and missing when up on a plane at higher rpms.

Thats the key right there. What could be fouling up the plugs so fast. Perhaps gasoline getting into the oil somehow. Just a thought.

 

[zvolv]

Re: 1984 Volvo Runs Rich!

I put in a new set of 4 plugs and the boat fired right up and we had fun for about 30 minutes and the engine was running great. Then it started backfiring and missing when up on a plane at higher rpms.

Thats the key right there. What could be fouling up the plugs so fast. Perhaps gasoline getting into the oil somehow. Just a thought.

The oil smells fine.

Is there supposed to be a small puddle of fuel in the bottom of the carb?

Can a bad ignition cause black plugs?

 

[CharlieB]

Re: 1984 Volvo Runs Rich!

No carb is supposed to have a puddle of fuel sitting anywhere than inside the float bowl.

From the repeated condition of the spark plugs this carb is running way too rich and fouling the plugs.

The correct Solex and the Volvo works fine, I expect that someone was hoping for a little more power from installing a larger carb, it 'could' make some improvement in power, but the float height and jetting must be correct or you could end up with the problems that you are having now.

Cross your fingers, clean and adjust this carb and start looking for the correct Solex carb.

 

[ccmarsh]

Re: 1984 Volvo Runs Rich!

Ignition system defects will cause engine misfire. If the spark plug electrodes are improperly gapped, excessively worn, or corroded, the engine will misfire during acceleration. You might also want to check the timing, make sure that the spark plugs are firing in the right order, and that the plug wires are in the right place and order but before you do all that you need to check the compression like Don says. Trust me, if Don says to try it, then try it.

 

[zvolv]

Re: 1984 Volvo Runs Rich!

First of all, thank you guys for your responses! I appreciate it!

I am certain the plug wires are connected correctly and in the right order otherwise the boat wouldnt have run fine for an hour or so. I did find one of the wires broke right off the boot when I pulled on it lightly. POS Sierra aftermarket wires! I had to put on a couple of spare wires to get it started. Then I didnt note the firing order, but I figured it out.

The more I think about it I believe its the carb. I showed the plugs to a few buddies and they think way too rich too. And its definately not the original carb for the boat. It also smelled like gas when the misfiring started to happen and the smoke from the prop during flushing didnt smell or look like oil. Smelled more like fuel.

I didnt have my compression guage or timing light with me at the time but I will definately put those on there just to check.

The fuel down in the carb also points towards flooding. It wouldnt start for a while when I got back to the dock and so I opened the throttle and aired out the carb for a while and she restarted.

I am still open for any tips or suggestions! Thanks!

 

[Don S]

Re: 1984 Volvo Runs Rich!

The carburetor doesnt appear to be original.The previous owner also made a comment along those lines too. Its a 2 barrel and it says made in spain.

My guess is you have either an automotive engine or an automitive intake and carburator.
Every AQ130 model put out by Volvo had 2 single bbl carbs
If that is the case, what else is automotive? Starter? Alternator? Distributor? FUEL pump????

While that may not be the cause of the problem it is a serious safety concern for you.

 

[bruceb58]

Re: 1984 Volvo Runs Rich!

My guess is you have either an automotive engine or an automitive intake and carburator.
Every AQ130 model put out by Volvo had 2 single bbl carbs
If that is the case, what else is automotive? Starter? Alternator? Distributor? FUEL pump????

While that may not be the cause of the problem it is a serious safety concern for you.

At least in the US, Volvo never offered a carb'd version of that engine for automotive use.

 

[Don S]

Re: 1984 Volvo Runs Rich!

The 130 is not the OHC engine with a timing belt. It's an OHV pushrod engine.

 

[zvolv]

Re: 1984 Volvo Runs Rich!

Its definately a boat manifold. I am also 95% certain its a boat carb.


I think I am just gonna buy a rebuilt Solex one barrel that is supposed to be on the boat.

And I am completely unsure of the engine designation. It is the OHC 4 cyl with timing belt. 1984.


These are pics from an ebay listing with the manifold our boat has, but these pics seem to have the proper Solex carburetor for the engine. Like I said, all I know about me carb is that its a 2 barrel made in spain when my boat is supposed to have a 1 barrel SolexFrom my research the carburetor its supposed to have is the Volvo Penta 1bbl Solex 44PA1. I definately do not have that carb on the boat

 

[Don S]

Re: 1984 Volvo Runs Rich!

You aren't listening. The 130's did not have a single carb nor a manifold like that.
Are you sure you have an AQ130A,B,C. or D engine?
How about some pictures of YOUR engines.

Just checked, the last year of 130's was 1977.
Somehow I bet you have a 131, which is a completely different engine.

 

[zvolv]

Re: 1984 Volvo Runs Rich!

I have no idea what engine it is. I will try to get pics of it up soon.

It has the exact same intake manifold as shown in the pictures though. Single carb.

 

[Don S]

Re: 1984 Volvo Runs Rich!

Probably an AQ125. Bayliner used a lot of them back then.

Look on the port side of the engine. Around the distributor and fuel pump. You should find a metal tag with model and serial number on it.

 

[zvolv]

Re: 1984 Volvo Runs Rich!

Probably an AQ125. Bayliner used a lot of them back then.

Look on the port side of the engine. Around the distributor and fuel pump. You should find a metal tag with model and serial number on it.

There is a metal tag on the bellhousing adaptor with a serial number on it. We wrote it down in the manual, but the boat and book are 20 miles away right now. Once I get that info I will cross reference it and figure out which engine it is.

As of right now its just an engine that fouls plugs!

 

[bruceb58]

Re: 1984 Volvo Runs Rich!

Is the exhaust manifold and intake manifold on the same side of the engine?

 

[zvolv]

Re: 1984 Volvo Runs Rich!

Is the exhaust manifold and intake manifold on the same side of the engine?

No.