AQ175A Volvo Penta Engine dies after a couple of minutes

[Privatear]

Volvo Penta AQ175A
Not long after changing the fuel filter the engine started to cut out after a couple of minutes. I can restart it usually just once but again it cut out after a while. It was suggested the fuel pump was the problem, fitted a new one, but the problem persists. Started cold engine this morning, run at 3000rpm for couple of minutes and engine cut out. Managed to restart on tick-over, ran for 15mins at 1000rpm and no probs. Increased revs to 2000rpm and after 30secs engine died. Waited 10mins, restarted on tick-over but engine died after a minute or so. Waited 15mins, started on tick-over, just keeps running steady at 700rpm. Hmmm?any ideas?
Cheers / Privatear

 

[Maclin]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

I would suspect there is an air leak on the suction side of the pump now especially if it was not doing this before the filter change. This could have been introduced from the filter change. Some times the screw-in filter's gasket sticks to the mounting and does not come off with the filter. Then when a new filter is installed the original gasket interferes. I would retrace those steps and double check everything involved with the filter change, a fitting could have been bumped too hard, filter too tight and gasket give out, etc. The filter itself could also be the problem, not the right one, or it has a leak around a seam, something like that...

 

[Maclin]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

My comments are based on you still having the stock replaceable element type scre on housing/filter setup. The element may not be seated well, or the housing cross threaded, or mounting/fitting not clean.

 

[Don S]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

If your filter is like the one pictured below, did you replace the gasket #28 ? If not, it's probably sucking air and causing your problem.
If you did replace it, check the bowl rim carefully, those are just thin metal and get damaged easily.

I normally remove those filters anyway, and throw them away. Then install a water separating fuel filter kit from any marine store. Much better filter and it will trap water too.

 

[Privatear]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

Thank you Don and Maclin, much appreciated. The filter body is the one in the illustration Don. I did buy a spare filter and a complete new water seperating filter but thought it would be too much trouble to fit. Sounds as though it might be worth it!
I'll let you know how it goes.
Thanks again / Privatear

 

[Privatear]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

Tried the other new filter. It'll run all day at 1500rpm max. Any higher and the engine just dies after a minute or two. Maybe the replacement filters aren't up to the job? Supposed to be the correct replacement ones. Wish I'd kept the original Volvo filter, would have been easy to check if it was a filter problem. (lesson learned). So, I'll fit the water separating kit. Running out of time this season though!
Thanks again.
Privatear

 

[Don S]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

Hook up a remote fuel tank (outboard tank) directly to the fuel pump and see how the engine runs.

Did you have any running problems prior to replacing your fuel filter? If not, and it actually ran for a while after changing the filter, I would have to think water in your fuel. When you originally replaced your fuel filter element, was there water in the bowl?

 

[Privatear]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

Morning Don,
When I originally replaced the filter there was no water in the bowl but when I put in the other new one yesterday there was about a quarter of a teaspoon (largish ball bearing) of water in the bowl. Can't remember exactly what happened when I first changed the filter. There was definitely no water in it but quite a few 'bits' that I cleaned out. Think I ran it for half an hour as a test and it was fine. Then a week later I was going out for the first trip and the engine dying problem started. I did have friends on board and a full holding tank on the way out so there was a definite list and the fuel level was low. Given the tank is 25yrs old there may well be water on the bottom. Only other thing was I took the old filter off, then it was 10 days before I put the new one on. So the fuel system was 'open' for that time.

No one around at the mo (tide out) for me to borrow a tank. So will buy the parts, (hose, hose barb, etc for fitting the water seperating filter) and I'll be able to connect the remote tank direct to the fuel pump and test.

Cheers Don

 

[Privatear]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

Hi DonS,

Back down for the weekend. 10 gals of new fuel in, put the new water seperating filer on - same problem - engine dies above 2000rpm. Connected a fuel line direct to the new fuel pump from an outboard tank - same problem. So I guess I now move on to the carburetor? Or could it be an electrical component failing?

The only other point is, you may recall, the engine compartment did flood early in the season, just to the level of the starter motor (I had that rebuilt) and I thought I'd cleaned everything. Could salt water have affected something?

It's been a beautiful day here on the river - there are compensations to this boating lark!

Cheers

 

[RogersJetboat454]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

So I guess I now move on to the carburetor? Or could it be an electrical component failing?

Could very well be some trash in the carb, or a float issue.
Electrically speaking, could be loosing spark, but... sounds allot more like a fuel starvation issue.

 

[Privatear]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

Thanks RogersJetBoat454,
That'll be next weekends job then! Last one of the season - hope I can fix it.
Cheers

 

[Privatear]

Re: AQ175A Volvo Penta Engine dies after a couple of minutes

Success! Thank you all.
There is also a small inline filter where the metal fuel line enters the float chamber. Removing the fuel line and unscrewing the cap nut gives access. Cleaned the filter (needs to be replaced though as pretty grot) and there was some improvement. Finally took the plunge and removed the carburetor cover, but float chamber clean as a whistle, so thought best left alone. Replaced the cover, started the engine to see if I had put it the cover back on okay, bit of a cough and splutter, and away she went sweet as a bird. What can I say? Perhaps sometimes you just need a bit of luck...or maybe...no, let's not go there. As Shakespeare said, "All's well that ends well." Happy autumn all.
Cheers