Engine problem Volvo Penta 145AQ

[spannerman]

Having read the above advice and guess you have checked the obvious, carbs adjusted correctly and opening fully, diagphragms OK.
Have you changed the condensor and points, could be worth a look. And as mentioned check the advance mechanism too. But my feeling is that the cam timing has jumped a tooth or two. Dead easy to check, there is a notch on the rear cambelt guidewasher on the crank, line it up with the small mark on the timing belt cover. (check No 1 is at TDC by looking at the rotor arm position, should be near No1 plug lead on the distributor cap) then if you look on the back side of the camshaft pulley you will see a notch which should line up with a mark on the front end of the cam cover if I remember correctly, although some engines lined up to the top surface of the cylinder head at either 3 o'clock or 9 o'clock. The best thing is to take off the cam cover and check the two lobes on No1 cam are both pointing upwards equally, any marks a very obvious on these motors, if it has jumped just slacken the tensioner and realign the belt, its worth considering changing it if it has jumped as it means its probably stretched, check the tensioner bearing too. These engines suffer from rusting on the cam drive pulleys so give it all the once over, you will have to remove the heat exchanger but its dead easy after that.
Good luck and definitely go after your £2k, sounds like he shouldn't be near anything more complicated than a can opener!

 

[ontheplane]

I fear the chances of getting my 2k back are pretty slim - the guy had VOLVO PENTA all over his van - but not in the Volvo font - turns out he isn't a volvo dealer/agent at all but if you read his paperwork VERY carefully it turns out he doesn't quite claim to be - just "specialises in Volvo Penta" (well anyone can do that).

My 2k has allegedly bought me a full service, oils filters etc, new bellows on leg, and a strip down and replace of the leg that had some issues (though I now am not sure that it did) - I am certainly not going back until I find what's wrong, then I might to see if I can get some money back.

So if you want your Volvo's serviced at Portishead in Bristol ask me and I'll tell you where NOT to go in a PM.

Back to the problem. I will try and get a photo of the engine / carb
I will also try to check the cam timing etc as suggested.

However I am still puzzled as to why removing the Air filters and Flame arrester cures the problem (although it still won't get on the plane with a 15in prop - so on that boat It's supposed to do about 20ish knots) so I do think quite down on power.

I will look into the things suggested thanks - any more ideas from anyone??

Grant

 

[overdrawn]

It does sound very rich,but do check all base settings first.
If it is not in tune it cannot burn the fuel efficiently so the plugs would be black.
Removing air box and arrestors may be leaning it off a bit,so it runs a little better whilst out tune

 

[Callisto]

If your plugs are black (and probably wet) you may actually be overfuelling and when you take the filter/arrester off, you are letting more air in which gets mixture closer to where it should be for decent combustion.

Solex carbs also have a float chamber under the top cover with a needle valve operated by the float, if this is stuck open as you wind open the throttle,t he fuel pump is shoving fuel through and the only place it can go is straight down the throat of the carb via any hole it can find main jet, idle jet etc, hence part flooding the engine.

I think you may have a carb problem and they can be overhauled quite easily. Also check the cam belt as Spannerman suggests though as I had a 250 series which was down on revs and that was a tooth out on the belt. Sorted it and much better. My idler was rusty too so a couple of good points to check.

Cheers

JH

 

[dt1]

your right black plugs is a sign of overfuelling,,what i couldnt understand is why the engine comes back too 1000rpm after it had bogged down normally a flooded engine would cut out ,then be difficult to restart, which made me think he was running out of fuel ,, white spots on plugs does indicate water in the fuel,,still after all this it could still be an ignition problem
,, i for one would love to know what the problem was,,once its been fixed. /forums/images/graemlins/confused.gif

 

[ontheplane]

Rest assured I will let you all know!!

Plan of attack is.....

1) Check cam belt/cam timing/idlers etc...
2) Check ignition timing, points, dwell angle etc
3) Strip carbs and rebuild - the muppet who did the service has allegedly done this but I now have no faith he's done it properly

after that - I don't know - but I need to find out what the prob is fast - I am so fed up with her I am selling her once this is sorted out.. I will get something smaller and hopefully cheaper to run - I'd forgotten how much boats this size cost to run!

Grant

 

[ontheplane]

Other point guys - anyone know where I can download something like a Haynes Manual for this thing?

 

[ontheplane]

WOOHOOOOOOOOOOOO

Thanks to all you lovely people, we MAY have found the problem with this f*c*i*g engine.. lol...

Having lined the timing mark on the crank up with TDC mark on the block, the camshaft pully mark is... yes you've guessed it... wait for it.... about 3 teeth on the cambelt out!!!!!!!! Weyhey we thought... is this the answer, will my boat perform now????

Anyhow, the belt looks pretty new.. and therein lies some questions -

1) Can you tell if a cambelt is new or old by it's look?
2) Can you tell from the tensioner if it's stretched?

From what I can see it looks almost new - so that opens up the possibility that rather than slipped - perhaps some numpty has actually replaced it and just fitted it wrongly!

We then tried to adjust the tensioner to allow us to move it and came upon the next snag - we can't see how on earth you adjust/slacken off the tensioner in order to adjust that timing. Also, how on earth do you replace the belt? It looks a mamoth job to get all the bits off to get full access for replacement, is it a case of a total front end of the engine strip and rebuild or is there an easy way?

From what a few people have typed, they've said things like "just slacken the tensioner" and "it should be simple after that" - well we are at the "after that" stage and have hit a brick wall!

Hoping you can come to the aid of one who now believes that all MBM forumites are gods and all Marine Engineers in Portishead in Bristol need to be shot.

Thanks

Grant

 

[scotty628]

aq lack of power

hey grant, just wondering how you got on with the penta aq. I have a very similar issue with my aq170. low / now power to get on the plane. wondering if u fixed it? cheers scotty

 

[carlton]

Grant - just sent you a PM.

 

[volvopaul]

That engine is one of the simplest ever apart from the pushrod lump.

Having just read all the post id said in my head its the timing too far advanced maybe he set the timing right but with the cam wrong the fuel was just pushed back as the inlet valves were partially open, anyway now your set up id 100% fit a new belt as once its been slackened off it really needs a new one.

Get a volvo car manuall from the 144 or 145 days, maybe download it from the haynes website.

Its easier the fit the belts and get it 100% right if you take off the heat exchanger off first.

Get it done then tell the vp guy how its done, good luck!

 

[scottie]

check the sea water pump for signs of leakage

Water leaking from the telltale hole can cause a build up of gunge on the pulleys causing cambelt slippage

 

[NorthUp]

petrol was only 88p a litre when this thread started........

 

[alruss]

Petrol has been in since last year, "kept tank full to avoid condensation". I thought this was a diesel thing and petrol oodoes not keep for very long. Could this be a contributing factor in power problem?

 

[spannerman]

The motor is based on the B series overhead cam engine, so a Volvo manual for a 244 / 245 will cover this as they used the B21 and B23 which are the same basic lumps, I cut my teeth on these engines back in the 80's.