Volvo Penta 290 SP-A ... Outdrive question.

[moresparks]

I am scratching my head on this one and wondered if anybody has had a similar problem.
At displacement speeds the drive is fine but at full forward load one of my drives seems to lift. The trim indicator has shown the drive in a slightly raised position and the feel of the throttles confirm this to be the case. I can also experience cavitation at planning speeds similar to prop slipping. I have marked the props and they seem o/k. On checking the hydraulic oil in the trim motor, it was a nice shade of pink – so water in the hydraulic oil. So RAM service this winter!
Is it possible for the drive to lift in forward? Or should I be looking elsewhere?

 

[robrennie]

I have two 290s on my boat. When the rams have worn out, the drives tend to fall down when going forward - so yours does seem a bit odd - one would think it was not possible for them to drift up when under power.

As a test to remove a wiring fault that may be driving the motor in an un-commanded way - would it be worth disconnecting the power to the trim tabs?

 

[moresparks]

Many thanks for your suggestion – I agree it does appear to be an electrical problem . I can cruise all day at displacement speeds with no movement on the drive but the moment I hit planing speeds one of the drives seems to lift, hence why I am scratching my head! The boat has been fine all summer and this is a sudden event but it did coincide with the sea water filter lid suddenly developing a leak and spraying water everywhere. Hopefully I can test further before the winter lift.

 

[CLB]

Under forward power, the leg will be forced down, so what you are experiencing MUST be caused by an external power source. Do as suggested and disconnect the power to the trim pump/motor. If it still rises, you need to consult a physicist, as you have found some new thing that defies physics

 

[BruceK]

......... you need to consult a physicist, as you have found some new thing that defies physics

Nothing associated with the word boat surprises me any more.

 

[QBhoy]

Hi
I can say with some certainty that there is likely no way your leg is raising when under way in a forward manner. Most likely the old well known VP sender cog wheel playing up or the calibration needing “0”d. Worst case scenario is the steering helmet bush is on its way out. This being the case, best have a look. This is starting to be a problem happening all too often on the 290 drive of a certain vintage.

 

[moresparks]

Hi apologies for resurrecting this thread but I still have an issue which is really puzzling me.
I did substantial work over the winter – replacing rams and checking pump connections. I had the prop checked for slip but still have a strange problem and wondered if anyone can suggest remedies.
To recap... Twin engine setup and under no wake speed everything is fine. If I increase to planing speed one of the drives seems to lose grip and the revs increase dramatically. The problem also occurs if Increase revs hard in reverse whist docking. At the beginning of the season I could get over the problem by being gentle on the throttles but now with half a seasons fouling the problem is worse. As the problem originated last season, I thought I cured it by replacing the reverse latch springs as one was broken. It still feels like a reverse latch problem and maybe I need to replace all the pawls and catches, but kicking up in forward seems to defy physics!
The trim readings do not alter so the rams or pump is not the issue.
Gear shift cables all checked and o/k.
As I am on a mooring checking is not easy without a yard lift so need to be well prepared.
So apart from the reverse latch mechanism, could anything else cause this problem?
Thanks in advance.

 

[Beamishken]

Are you sure the drive is actually kicking up it sounds to me like it could be the drive clutch starting to slip

 

[moresparks]

Hi – Thank you for responding.
Re Drive Clutch.... I just don’t know – I cannot be sure its kicking up as you cannot see. I suppose I was hoping it maybe easy and shut my mind to the drive clutch!!! as I am not sure how this works on the 290 SP-A.
Are my symptoms similar to a failing drive / cone clutch?
The drives are nearly 30years old and as far as I know the cone clutch is original.

 

[robrennie]

Hi there,

I am pretty sure there is no way the leg can kick up going forward, the kick up problem is usually when the reverse catch doesn’t work.

Sounds like the clutch to me - I have over the last couple of years replaced mine on both outdrives, at around 1000 hours.

If the boat is out of the water, take a little bit of oil out, if the clutch is knackered it will smell awful.

 

[moresparks]

Hi... Apologies for being a pain but if it “is” the cone clutch it is probably season over, so forgive me for seeking confirmation.
I assumed that if the cone clutch was faulty I would have problems selecting either reverse or forward and the gear selection is fine.
Am I mistaken and the drive slip at higher revs is highly likely to be the cone clutch?

 

[[2068]]

It could also be the rubber “bush” on a propellor that is slipping and needs replacing.
Easy way to test if this is the case - swap props and see if the problem swaps sides too
Propellors can be re-bushed ... there are places that have a hydraulic press. Or get another prop.

If not, then start looking at more expensive fixes.

.

 

[robrennie]

You are not being a pain mate.

So when mine went, it was at low revs and in both forward and reverse - what would happen is that I put it in gear there was no drive, when I increased revs there would be a bump and it would start power.

The idea above on props is worth a look - seems entirely plausible to me and would make sense with your loss of drive at higher revs - much cheaper fix too!

All the best

 

[moresparks]

I can recheck the prop no problem. But I will be disappointed as the prop is only a couple of seasons old and I had it checked specifically for prop slip over the winter by sending it away to a specialist prop repair company.
Many thanks for your suggestions.

 

[aquatom]

If one outdrive is not providing enough drive it is possible for it to kick up if the other drive is pushing the boat through the water fast enough.

 

[CLB]

Assuming both props are handed the same, try swapping them over to see if the problem moves with them. If they are differently handed, you could still do this but would need to move the throttles to reverse to go forward.

 

[oldgit]

There is no clutch as such in the leg,ie no friction plate to burn out and smell ,only the cone which slides up and down a shaft. A metal to metal contact.
The only stink would be from the lubricating oil itself which can be bit acrid. ?
There is a nearly new cone for 290 being advertised on ebay at the moment.
If the cone is working well there should be a detectable "clonk" coming from the leg on drive engagement.

Quick simple in the water test would be to run each engine/leg seperately.
A few mins at WOT each side and see if there is any difference in performance.
If the boat has to come out of the water vital to check both legs while you are at it.

 

[moresparks]

Hi, I do get the typical Volvo “clonk” on the drive engagement both in forward and reverse and they are identical on both engines.
All the symptoms point to a spun prop hub – BUT I have had that professionally checked “supposedly”. Anyway I removed the prop and marked the inner and outer hub and will try again. I will also run just on the offending engine in case the momentum of the other engine is forcing the drive upwards.
As the props are handed I did not want to swap them over, anyway knowing my luck I will drop one in the drink!
Many thanks for your suggestions.
Shame really, toying with the idea of moving upwards to a shaft drive boat as I am getting older and weaker to lift 2 heavy stern-drives every couple of years for the full service and bellows change.

 

[oldgit]

Shame really, toying with the idea of moving upwards to a shaft drive boat as I am getting older and weaker to lift 2 heavy stern-drives every couple of years for the full service and bellows change.

No Comment .

 

[CLB]

Shame really, toying with the idea of moving upwards to a shaft drive boat as I am getting older and weaker to lift 2 heavy stern-drives every couple of years for the full service and bellows change.

Just take the top section off in that case.