Slow starting volvo

[TAMD60C]

Hello,
My first post ,But i have been reading posts for a while so go easy on me .
I have 2 Volvo Penta Tamd 60c engine (1985) with 2500 hours logged. During this summer they have been starting slower & slower .I was told to try a heater in the engine room which improved the starting speed . Why does this help ?

I also serviced all 12 injectors which had know effect & engines are serviced every year .Other than the slow starting problem they run fine & have never missed a beat .
Does the panel think I have a compression problem or is it time for a re-build ?
Any help you be greatly appreciated as I'm only on the water a year
Thanks & what a great forum this is

Tom

 

[Whitelighter]

Just a quicky, have you checked the condidion of your start batteries. Big lumps like that take a serious amount of juice and if you have batteries on the way out it could gives the symptoms you describe.

 

[TAMD60C]

Hi Jezbanks,
I replaced all the starting batteries at the start of the season so hopefully that's not my problem .
I thought my starters might be in need of a re -con .what do you think?

 

[volvopaul]

Firstly is the boat 12 volt or 24, if 24 then it may be the starters are getting ready for new brushes and a clean up on the comm, at 2500 hours there hardly used but the bores could be glazed if you dont run them hard, so compression may be an issue here, or the valve seats are worn and compression is lost there.

I worked on old fairline 40 few weeks back, from 1982 vintage, apart from new heat exchngers and some other bits they started within 5 secs of turning the keys my mate roger has a pair in his ocean 42 he recons they must have done 6000 plus hours now without the heads being off one of the engines.

The early motors dropped a few valves in there time so beware, best look into it before its too late.

 

[TAMD60C]

[ QUOTE ]
Firstly is the boat 12 volt or 24, if 24 then it may be the starters are getting ready for new brushes and a clean up on the comm, at 2500 hours there hardly used but the bores could be glazed if you don't run them hard, so compression may be an issue here, or the valve seats are worn and compression is lost there.

I worked on old fairline 40 few weeks back, from 1982 vintage, apart from new heat exchngers and some other bits they started within 5 secs of turning the keys my mate roger has a pair in his ocean 42 he recons they must have done 6000 plus hours now without the heads being off one of the engines.

The early motors dropped a few valves in there time so beware, best look into it before its too late.

[/ QUOTE ]
Thanks Volvopaul,
She is 24 volt so i might look into replacing the brushes.
I tend to drive her on (75% throttle/20 knots) on long passages ,but 10 knots most weekends .
When you say "early motors dropped a few valves in there time" What should i do on this ? What should i do to prevent this ?
What do you think of the way a small heater helps them start faster ?
Thanks for the help
(I might be sorry for asking with you mentioning dropped valves /forums/images/graemlins/blush.gif)

 

[volvopaul]

Have you got a broom then? I work on quite a few.

Heater in the engine room to help start suggests worn rings or low compression, do you get a lot of smoke and fumes out of the breather filters when your under load, 20 knots sounds good unless its a light boat.

 

[TAMD60C]

[ QUOTE ]
Have you got a broom then? I work on quite a few.

Heater in the engine room to help start suggests worn rings or low compression, do you get a lot of smoke and fumes out of the breather filters when your under load, 20 knots sounds good unless its a light boat.

[/ QUOTE ]
Thanks Volvopaul
I have a Neptunus ( Dutch & 12 ton )
The crankcase filters don't smoke when under load .Just a slight mist which gets sucked into the air filters .
They run fine & only use a small amount of oil when run hard for a long period .

 

[DavidJ]

Putting on my trouble shooting hat rather than having particular knowledge of your engines. I'm intrigued that the problem is with both engines. It's statistically unlikely that brushes, glazed bores etc will happen at the same time so it's something both engines use in common. There can't be many. Electrical earthing points? Thicker oil at last service? etc etc maybe try and brainstorm a few more.

 

[ExcaliburII]

At risk of being pedantic, I think we need a clearer definition of "slow starting" here, as the two interpretations could have vastly different causes. Different peeps are throwing in good advice based on different scenarios.

1. Both engines turn over very slowly on their starter motors.

A poor earth connection, especially if common to both engines and/or battery banks would get my attention first. As others have said, if the symptoms are common to both engines, it is most likely the cause will be too.

2. Both engines spin over at a good speed, but take a long time to catch.

No point in looking for problems with the starter motors for this one and, again, if the symptoms are the same for both, what is common to both engines? Oil too thick sounds like a good suggestion (especially if warming them up improves things). Or what about the fuel system? Has it got something in it (ie apart from clean fresh diesel)?

 

[TAMD60C]

[ QUOTE ]
At risk of being pedantic, I think we need a clearer definition of "slow starting" here, as the two interpretations could have vastly different causes. Different peeps are throwing in good advice based on different scenarios.

1. Both engines turn over very slowly on their starter motors.

A poor earth connection, especially if common to both engines and/or battery banks would get my attention first. As others have said, if the symptoms are common to both engines, it is most likely the cause will be too.

2. Both engines spin over at a good speed, but take a long time to catch.

No point in looking for problems with the starter motors for this one and, again, if the symptoms are the same for both, what is common to both engines? Oil too thick sounds like a good suggestion (especially if warming them up improves things). Or what about the fuel system? Has it got something in it (ie apart from clean fresh diesel)?

[/ QUOTE ]

Both engines spin over at a good speed, but take a long time to catch .I have been putting 15w 40 oil into these engines .
The fuel system is clean & treated with fuel set on ever fill up .

 

[volvopaul]

Do you get white smoke when turning over before they fire up, approx how long before they do fire, could be pump timing as timing gears wear over the years, is the stop solenoids returning fully to run position.

maybe get a compression check carried out this winter.

 

[ExcaliburII]

Right, if they turn over at a good speed we can assume there's nothing wrong with the starters, and oil & fuel seem OK from what you have said. The trouble with diagnosing problems like this at a distance is that you miss out on all the semi-hidden, almost subconscious clues. So, some more questions (in addition to VolvoPaul's):

1 Do you only get the problem from cold, or is it the same when the engines are up to temperature and have only been stopped for a short time?

2. When they do catch, do they instantly go from totally lifeless to running smoothly, or is it a sort of gradual "fire on one pot, splutter, cough, nothing, fire again, bit more, chug, chug, faster, faster, OK, we can manage without the starter motor now, phew!" sort of event? (This ties in with VP's query about the white smoke as well which is another clue.) Sudden transition from lifeless to sweetness and light would indicate fuel suddenly becomes available at that point, so look for something stopping it being delivered until then (eg stuck stop solenoid being shaken free). If the gradual process, I would guess there's fuel there but volume and/or timing are screwed. Or, something more serious like loss of compression. However, if symptoms on both engines are the same this would be a quite remarkable coincidence.

You said things have been gradually getting worse over the season - have both engines always been about the same or is/was one worse than the other?

It is very rare for more than one thing to go wrong at any given time, so if lots of different symptoms suddenly appear, you can almost always work back to a single cause and fix that.