pete1987
Active Member
The set up shown in Marcus' photo is almost identicle to mine so this seems to be the original installation.
wheel needs 18turns from lock to lock???
- Thread starter vas
- Start date
david_bagshaw
Well-Known Member
Certainly having a bigger ram could play havoc with the auto pilot, as it would take longer to apply a course correction than the system would expect.
There is probably an adjustment via dip switches to compensate for the time for lock to lock. consult the instruction book, it will be in there some where.
good luck.
There is probably an adjustment via dip switches to compensate for the time for lock to lock. consult the instruction book, it will be in there some where.
good luck.
vas
Well-Known Member
thanks again for all comments/suggestions.
What I forgot to mention is that A/P was changed from something to the current 618 CETREK sometime in the past (mid 90ies?). Two scenarios I can think of:
A. It MAY just be that at the time the A/P wasn't working as it should with the existing setup and they decided to fit an oversize ram, messing the helms and messing a bit less the A/P action.
B. They fitted the new A/P with the old ram, all was fine and then the ram started leaking and replaced it with the big 'n messing both helms and a/p response, but couldn't care less and left it as is.
I'll dismantle the old ram in a mo and see what I get, send it to be pressure tested tomorrow and then figure out if scenario B was likely to be the one. Judging from the things I've seen around MiToS I'd put my money on B.
Still cannot understand how air in the system can make something work from 4-5 turns to 4 times that
.
I mean from car brake and clutch bleeding experience, I simply don't get it. Yes air compresses, but there aint any up at the helm pump so pump is picking and pressing oil down the pipe. On the ram side, if there's any air, it would buble and still move the rudder albeit if forced against the movement the rudder would shift back a bit (don't see it happen, not even on full lock)
Anyway, tomorrow should make things much clearer with the venting of the ram.
cheers
V.
What I forgot to mention is that A/P was changed from something to the current 618 CETREK sometime in the past (mid 90ies?). Two scenarios I can think of:
A. It MAY just be that at the time the A/P wasn't working as it should with the existing setup and they decided to fit an oversize ram, messing the helms and messing a bit less the A/P action.
B. They fitted the new A/P with the old ram, all was fine and then the ram started leaking and replaced it with the big 'n messing both helms and a/p response, but couldn't care less and left it as is.
I'll dismantle the old ram in a mo and see what I get, send it to be pressure tested tomorrow and then figure out if scenario B was likely to be the one. Judging from the things I've seen around MiToS I'd put my money on B.
Still cannot understand how air in the system can make something work from 4-5 turns to 4 times that
.I mean from car brake and clutch bleeding experience, I simply don't get it. Yes air compresses, but there aint any up at the helm pump so pump is picking and pressing oil down the pipe. On the ram side, if there's any air, it would buble and still move the rudder albeit if forced against the movement the rudder would shift back a bit (don't see it happen, not even on full lock)
Anyway, tomorrow should make things much clearer with the venting of the ram.
cheers
V.
Divemaster1
Well-Known Member
Question Vas,
You would have noticed this on your delivery trip .... can you recall having to turn the wheel like that then? .... I am sure you would have reacted then... so suspect answer may be simpler....
You would have noticed this on your delivery trip .... can you recall having to turn the wheel like that then? .... I am sure you would have reacted then... so suspect answer may be simpler....
vas
Well-Known Member
Yep, turning to no end, hence stopped bothering and was using the engines...
Further, spotted the leak in the lower helm and was trying to avoid using the wheel as it was pssing more oil down there and had to constantly fill the top helm wheel.
So, I'd say the problem was there when I got her (only there were two probs, and last week I sorted the leak)
off to take appart the old ram, brb
V.
vas
Well-Known Member
not quite right back, but I dismantled and cleaned the bits.
Now, first of all there is a 2540.3 stamped on the body of the ram. Does it mean something to anyone??? Not to me it doesn't.
Further how it compares to the 345 cm3 of the current ram?
Second, all seems sound, seals are nice and softish (well after 40yrs I'm impressed they are not breaking apart on touch!)
Problem is that both threads where the two pipes were connected have a leftover piece of yellow pipework broken in and flush to the body of the ram.
Took me 10secs to unscrew with a sharp thin flat screwdriver pushing this plastic ring around in a tangent.
I cannot imagine that on removing the pipework to install the new A/P they managed to break both inlets and they decided to change ram, but what do I know
I'll get a set of seals locally (shouldn't be more than 10euro) and I'll have it on standby.
Once I figure out the capacity of the helm stations AND the A/P pump, I should be able to decide what to do.
Update in the evening after I return from MiToS
cheers
V.
Now, first of all there is a 2540.3 stamped on the body of the ram. Does it mean something to anyone??? Not to me it doesn't.
Further how it compares to the 345 cm3 of the current ram?
Second, all seems sound, seals are nice and softish (well after 40yrs I'm impressed they are not breaking apart on touch!)
Problem is that both threads where the two pipes were connected have a leftover piece of yellow pipework broken in and flush to the body of the ram.
Took me 10secs to unscrew with a sharp thin flat screwdriver pushing this plastic ring around in a tangent.
I cannot imagine that on removing the pipework to install the new A/P they managed to break both inlets and they decided to change ram, but what do I know
I'll get a set of seals locally (shouldn't be more than 10euro) and I'll have it on standby.
Once I figure out the capacity of the helm stations AND the A/P pump, I should be able to decide what to do.
Update in the evening after I return from MiToS
cheers
V.
PaulGooch
Well-Known Member
Now you have it apart, can you partially assemble it, so you could push the piston to one end and tip fluid in and see how much it holds ?
BartW
Well-Known Member
I forgot to announce that MapisM found out, and prooved that this zig zag effect on Blue Angel (only at planing speed)
can be improved to almost no zigzag, just by the settings of the A/P
we still have to do some fine tuning at completely flat see,
but at least I'm now convinced that my rudder system is OK, and that we can improve A/P behaviour just by the settings.
vas
Well-Known Member
Right,
old ram is imperial units, so unlikely to be the original equipment in an Italian craft... Could be part of the package deal with the CETREK AP though... Hence couldn't find ANY of the seals off the shelf, got to order them, checked with the pump guy and he recons it should be ok, so I'll try it, if it doesn't leak I'm keeping as is. So it's not 40yo and that's why the seals are okayish.
Instead of filling it up with fluid and measuring as Paul suggested and since it's dead easy to measure piston travel and inner/outer dia of the area, I did my calcs:
Outer dia for the fluid: 25.4mm
Inner dia (i.e. the ram shaft) 12mm
Travel 138mm
So outer vol is 69.9cc
inner vol 15.6cc
subtract and you get 54.3cc
compared to the 348cc of the current ram means it's 6.4 times smaller ie faster, so with the 54cc ram, I'd get just around 3turns from lock to lock, which is a tad on the fast side, but should be ok.
This bit done, had a look at the helm stations pumps and mainly on the f/b one that is fully exposed and easy to spot any screws /trimmers etc. NOTHING, plain thing, three pipes to it and on top a cup to fill up oil. So Alf, no way I can speed up so to speak the helm.
Lower helm although inaccessible does seem to have something at the rear but I think it's only markings and nothing you can regulate flow from:
Also, anyone knows what this thing is? It's under the lower helm inline to the other box (the one that was leaking) before it meets the f/b pipes:
Final bit was checking the A/P pump. checked CETREK literature, but the pumps they mention don't quite look like the one I have installed.
It's a FRACMO from Hastings England as it says on the nice label that has NO info printed on! Amazing...
I can see on either side by each outlet there are 2 screws a big 'n and a small. These I guess could be some sort of strangling regulation thingy, but I have to find info or start testing.
Final test I did was turn on AP, having the rudders turned fully to one side, and with AP in standby and a theoretical route to whereever the compass says, I hit the pilot button so effectively the AP is steering. It takes around 10-12secs to get the rudders in straight from full lock. Reading the CETREK manual and remember from other sources on a planning craft lock to lock the AP should do it in 9-12sec, mine now does it in almost 25...
So looks to me that things are going to be manageable and crisp if I change the ram to the other one.
Anyone thinks there's something wrong/missing in the above?
If not, I guess I have to remove the other one and fit this. I'll test fit it temporarily and if it's working. I'll refurb all the flex pipework as it's rubber gone horribly hard and I don't like it.
cheers
V.
old ram is imperial units, so unlikely to be the original equipment in an Italian craft... Could be part of the package deal with the CETREK AP though... Hence couldn't find ANY of the seals off the shelf, got to order them, checked with the pump guy and he recons it should be ok, so I'll try it, if it doesn't leak I'm keeping as is. So it's not 40yo and that's why the seals are okayish.
Instead of filling it up with fluid and measuring as Paul suggested and since it's dead easy to measure piston travel and inner/outer dia of the area, I did my calcs:
Outer dia for the fluid: 25.4mm
Inner dia (i.e. the ram shaft) 12mm
Travel 138mm
So outer vol is 69.9cc
inner vol 15.6cc
subtract and you get 54.3cc
compared to the 348cc of the current ram means it's 6.4 times smaller ie faster, so with the 54cc ram, I'd get just around 3turns from lock to lock, which is a tad on the fast side, but should be ok.
This bit done, had a look at the helm stations pumps and mainly on the f/b one that is fully exposed and easy to spot any screws /trimmers etc. NOTHING, plain thing, three pipes to it and on top a cup to fill up oil. So Alf, no way I can speed up so to speak the helm.
Lower helm although inaccessible does seem to have something at the rear but I think it's only markings and nothing you can regulate flow from:
Also, anyone knows what this thing is? It's under the lower helm inline to the other box (the one that was leaking) before it meets the f/b pipes:
Final bit was checking the A/P pump. checked CETREK literature, but the pumps they mention don't quite look like the one I have installed.
It's a FRACMO from Hastings England as it says on the nice label that has NO info printed on! Amazing...
I can see on either side by each outlet there are 2 screws a big 'n and a small. These I guess could be some sort of strangling regulation thingy, but I have to find info or start testing.
Final test I did was turn on AP, having the rudders turned fully to one side, and with AP in standby and a theoretical route to whereever the compass says, I hit the pilot button so effectively the AP is steering. It takes around 10-12secs to get the rudders in straight from full lock. Reading the CETREK manual and remember from other sources on a planning craft lock to lock the AP should do it in 9-12sec, mine now does it in almost 25...
So looks to me that things are going to be manageable and crisp if I change the ram to the other one.
Anyone thinks there's something wrong/missing in the above?
If not, I guess I have to remove the other one and fit this. I'll test fit it temporarily and if it's working. I'll refurb all the flex pipework as it's rubber gone horribly hard and I don't like it.
cheers
V.
PaulGooch
Well-Known Member
That ram is not big enough, it will give you around 2.8 turns lock to lock. That's going to be very hard to steer indeed and may well overpower the A/P (be too hard for the pump to work, or even damage the pump).
vas
Well-Known Member
just the thing I didn't want to hear, but was slightly afraid of...
thanks, so I have two rams and must buy a third one?
Do that, or replace the helm pumps? I wonder what is cheaper more reasonable to do.
Mind, forgot to mention that with all this testing and turning against the AP, checking etc level at the f/b pump didn't move at all.
Vented the nipples on the ram, no air straight liquid from them.
HOWEVER, with the AP off, I can reach the lock on either side and on trying to turn the wheel hard on the lock, I get enough resistance. If I keep on trying to turn, after a sec or so it gives in and I turn the wheel another 10-20degrees before it sort of locks again hard, but pushing I can go over it as well ad nauseam. Just got bored after 3 full turns and stopped.
Does it mean something is slightly leaky (internally)?
Would that be the helm pumps or the ram?
No leaks anywhere to be seen, and no level drops after this exercise.
Suggestions?
V.
thanks, so I have two rams and must buy a third one?
Do that, or replace the helm pumps? I wonder what is cheaper more reasonable to do.
Mind, forgot to mention that with all this testing and turning against the AP, checking etc level at the f/b pump didn't move at all.
Vented the nipples on the ram, no air straight liquid from them.
HOWEVER, with the AP off, I can reach the lock on either side and on trying to turn the wheel hard on the lock, I get enough resistance. If I keep on trying to turn, after a sec or so it gives in and I turn the wheel another 10-20degrees before it sort of locks again hard, but pushing I can go over it as well ad nauseam. Just got bored after 3 full turns and stopped.
Does it mean something is slightly leaky (internally)?
Would that be the helm pumps or the ram?
No leaks anywhere to be seen, and no level drops after this exercise.
Suggestions?
V.
Divemaster1
Well-Known Member
The device at your helm may enable you to disconnect the flybridge main system and also function as a one way valve system ... so this may cause some issues for you if leaking...
BartW
Well-Known Member
Vas, can I hijack your thread for my question ?
its a bit appropriate here:
I have two new pressure hoses, and had renewed the seals on 2 cylinders from my passerelle,
going to fit this next week,
can someone explain me how to bleed the system ?
how can I be sure that all the air is out ?
its a bit appropriate here:
I have two new pressure hoses, and had renewed the seals on 2 cylinders from my passerelle,
going to fit this next week,
can someone explain me how to bleed the system ?
how can I be sure that all the air is out ?
vas
Well-Known Member
an update since I managed to clear up the f/b and removed the steering wheel and assembly.
Steering pump (or however you call this thing) has a
SEIPEM.GE and 2500/8 stamped on it.
google's your friend and you come up with
SEIPEM in Genova IT doing hydraulic systems for the last 40yrs apparently, so mine was one of their first attempts.
Funnily enough, they are also the producers of the old steering ram!
So story seems to be coming together at last
Now, the 2540.3 on the ram and the 2500/8 on the steering wheel pump don't feature on any of the PDFs I picked up from their site but I would hazard a guess that they are original equipment on MiToS, so will have a go at fitting them.
Actually the steering ram on the first page of the relevant PDF seems to have the right 3/8'' fittings and dims (will check for sure tomorrow as the ram is not at home.
Should be fitting again the steering pump on the f/b tomorrow so will test on Tue if I have enough time.
V.
Steering pump (or however you call this thing) has a
SEIPEM.GE and 2500/8 stamped on it.
google's your friend and you come up with
SEIPEM in Genova IT doing hydraulic systems for the last 40yrs apparently, so mine was one of their first attempts.
Funnily enough, they are also the producers of the old steering ram!
So story seems to be coming together at last
Now, the 2540.3 on the ram and the 2500/8 on the steering wheel pump don't feature on any of the PDFs I picked up from their site but I would hazard a guess that they are original equipment on MiToS, so will have a go at fitting them.
Actually the steering ram on the first page of the relevant PDF seems to have the right 3/8'' fittings and dims (will check for sure tomorrow as the ram is not at home.
Should be fitting again the steering pump on the f/b tomorrow so will test on Tue if I have enough time.
V.
vas
Well-Known Member
more Qs re steering/fluids/bleeding et al
Managed after a lot of hassle to re fit the steering pump on the f/b in it's new position and connect all pipework.
So filled up with fluid and started turning the wheel left and right to get it to fill up and bleed the thing. Mind it was only the steering pump removed and that's the top of the whole assembly so shouldn't really need anything else for bleeding.
Started with wheel turning like crazy no feel to it, eventually started stiffening and becoming notchy and after 4-5mins fooling around I have an operational (albeit 18turn!) f/b helm
Great, so next step will be to replace the 345cc ram with the 5something cc ram and see what happens.
HOWEVER, the thing is that f/b helm is now quite towards VERY heavy and very notchy! Don't ask if it was like that before, I *think* it's worse than before.
From various posters it seems that there maybe air in the circuit.
I'll do the A/P steer right, me steer left trick again tomorrow on both wheels but I don't honestly see it coming together... What else could I be missing?
Finally a fluid Q, previous owner was using some red coloured automatic transmission oil in the steering system. Is that okay or should I bleed the whole thing with something else? Dunno, steering wheel fluid, brake fluid??
cheers
V.
Managed after a lot of hassle to re fit the steering pump on the f/b in it's new position and connect all pipework.
So filled up with fluid and started turning the wheel left and right to get it to fill up and bleed the thing. Mind it was only the steering pump removed and that's the top of the whole assembly so shouldn't really need anything else for bleeding.
Started with wheel turning like crazy no feel to it, eventually started stiffening and becoming notchy and after 4-5mins fooling around I have an operational (albeit 18turn!) f/b helm
Great, so next step will be to replace the 345cc ram with the 5something cc ram and see what happens.
HOWEVER, the thing is that f/b helm is now quite towards VERY heavy and very notchy! Don't ask if it was like that before, I *think* it's worse than before.
From various posters it seems that there maybe air in the circuit.
I'll do the A/P steer right, me steer left trick again tomorrow on both wheels but I don't honestly see it coming together... What else could I be missing?
Finally a fluid Q, previous owner was using some red coloured automatic transmission oil in the steering system. Is that okay or should I bleed the whole thing with something else? Dunno, steering wheel fluid, brake fluid??
cheers
V.
rbcoomer
Well-Known Member
Not an expert, but I wouldn't think brake fluid would be a good idea! It can be quite corrosive if components aren't designed for it.
My guess would be that it's an AQF type power steering fluid?
I think the the air could take a while to work out and I think I'd check first for any high points/loops in the pipes where air could get trapped and eliminate if possible. Then I'd work it for a while and leave to settle. Repeat this a few times as the small air bubbles could take their time to find their way up to the highest point (hopefully the reservoir!) The warmer the outside temperature, the less time this should take. I don't know much about power steering on a boat, but where does the pump get it's power - engine or electric pump? Assuming engine, is the belt tight or could it be slipping? I'd imagine that insufficient power would make it heavy or failing that, issue with the pump perhaps?
My guess would be that it's an AQF type power steering fluid?
I think the the air could take a while to work out and I think I'd check first for any high points/loops in the pipes where air could get trapped and eliminate if possible. Then I'd work it for a while and leave to settle. Repeat this a few times as the small air bubbles could take their time to find their way up to the highest point (hopefully the reservoir!
) The warmer the outside temperature, the less time this should take. I don't know much about power steering on a boat, but where does the pump get it's power - engine or electric pump? Assuming engine, is the belt tight or could it be slipping? I'd imagine that insufficient power would make it heavy or failing that, issue with the pump perhaps?
david_bagshaw
Well-Known Member
Most likely to use a light viscosity hydraulic oil, Agricultral supplier will be best bet, or truck supplier.
We use similar with a single wheel and a non reversing electro hydraulic power pack.
Thick oil will make it heavy, notchy, suggest there is a problem with the pump, if the rudders are free. Have you tried moving the rudder with the ram disconnected, should be easy and not bind.
DO NOT USE BRAKE FLUID, as it almost certainly will ruin the seals.
We use similar with a single wheel and a non reversing electro hydraulic power pack.
Thick oil will make it heavy, notchy, suggest there is a problem with the pump, if the rudders are free. Have you tried moving the rudder with the ram disconnected, should be easy and not bind.
DO NOT USE BRAKE FLUID, as it almost certainly will ruin the seals.
Last edited:
PCUK
Well-Known Member
We use jack oil from most car shops.
vas
Well-Known Member
reviving a 6m old thread 
since I uncovered the f/b and superstructure, I've done some work on the f/b helm and inevitably had another go at turning the wheel (both f/b and lower helm) left and right checking for bubles and generally fooling around.
Still notchy, still 18turns, still possible to turn the wheel further and further once it reaches the end of the travel
Without great difficulty, I managed 3-4 turns of the wheel whilst on full lock 
Just have to do it slowly and not aggressively.
Mind can be done both on f/b and lower helm.
Seriously considering removing all fluid and refilling.
Currently using Automatic transmission fluid. Should I change to thinner/thicker or what?
Also considering fitting the other ram with the newly replaced seals and see what happens (and avoid getting into the fluid replacement palaver...)
Anyway, got to work on the lazarette, so I might as well start with some of these actions.
Any further ideas?
Especially what does it mean to be able to slowly turn the wheel when on full lock!
To me it would meant that:
A. ram seals gone
B. oil wrong viscosity.
cheers
V.
since I uncovered the f/b and superstructure, I've done some work on the f/b helm and inevitably had another go at turning the wheel (both f/b and lower helm) left and right checking for bubles and generally fooling around.
Still notchy, still 18turns, still possible to turn the wheel further and further once it reaches the end of the travel
Without great difficulty, I managed 3-4 turns of the wheel whilst on full lock Just have to do it slowly and not aggressively.Mind can be done both on f/b and lower helm.
Seriously considering removing all fluid and refilling.
Currently using Automatic transmission fluid. Should I change to thinner/thicker or what?
Also considering fitting the other ram with the newly replaced seals and see what happens (and avoid getting into the fluid replacement palaver...)
Anyway, got to work on the lazarette, so I might as well start with some of these actions.
Any further ideas?
Especially what does it mean to be able to slowly turn the wheel when on full lock!
To me it would meant that:
A. ram seals gone
B. oil wrong viscosity.
cheers
V.
david_bagshaw
Well-Known Member
quite usual with hydraulic steering to be able to continue to turn the wheel, but not very far. if you hold pressure on the wheel then let go and re pressure, the wheel will move round a few degrees, then go firm again.
If you are able to turn it further with constant pressure, afraid the pump or ram are worn out or you have a leak.
If you are able to turn it further with constant pressure, afraid the pump or ram are worn out or you have a leak.