Vp dpe trim reading issue

Lochlomond

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Joined
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www.campbellsairconditioning.co.uk
God you have to love boats or go insane it’s fix 1 thing for another 2 to crop up.

Serviced legs recently and afterwards Starboard leg all good but Port leg would not go back down, traced fault to helm switch, quick £100 at keypart for new switch and all good. (Swapped connections at helm switch to find fault originally).

After fitting new switch decided to test legs through full range and starboard decided to play up, as I buzzed up would suddenly jump from -5 to 15 then continue to rise to 40+ with my finger no longer on button nor the leg actually moving up. Ignition off then back on display -5 then again jump to 15 and repeat. Assumed sensor gone wonky and wallet out time again.

Been back to boat at the weekend and over both days behaviour has changed, ignition on leg fully down shows -6 or -5 and if I raise leg to say -2 to 0 all good, I can then raise all the way to 40 + and back down to -2 or -3 or anywhere before that with no issue but as I creep towards -5/-6 it then starts to play silly buggers again and the gauge heads upwards even with my finger still on down?

I’m hoping it’s not a faulty sensor as access is horrible and tight as, did playing around swapping helm switches to diagnose port fault cause issue or is it possible while servicing leg that the little toothed cog jumped a tooth in the rack knocking things out. All help appreciated, cheers Campbell
 
That'll be a sensor, don't ask how I know.

And yes, access can be a little tight... again don't ask how I know ;) Actually, I can't complain much... access wasn't too bad. But having looked at other sports cruisers, I just don't know how it'd be possible to change.

VolvoPaul mentioned removing the air inlet tube, which makes sense and looks like it would have given more access, if needed.

BTW, in my case, the sensor wouldn't play up until a few minutes into a trip... I don't know was it the heat causing erratic readings... could have been co-incidence.
 
That'll be a sensor, don't ask how I know.

And yes, access can be a little tight... again don't ask how I know ;) Actually, I can't complain much... access wasn't too bad. But having looked at other sports cruisers, I just don't know how it'd be possible to change.

VolvoPaul mentioned removing the air inlet tube, which makes sense and looks like it would have given more access, if needed.

BTW, in my case, the sensor wouldn't play up until a few minutes into a trip... I don't know was it the heat causing erratic readings... could have been co-incidence.

Thanks Alt, my worst fear as the Targa 37 is so tight in the engine bay, not looking forward to this at all. Maybe pay an engineer to replace lol
 
Been there too. Throw a duvet over the top of the engine and squeeze your way in. It's a bit of a handful but once in easy enough to get to. My biggest issue was to get it to line up with the shaft on the gear wheel. As it turned out I had to remove the helmet from the drive and insert the shaft from the bottom to locate into the new sensor. Cause of failure appeared to be growth on the underside of the wheel (not visible until dismantled) forcing it upwards hence the shaft was about 2mm too high for the sensor to relocate once the old one had been removed. Remember this if you struggle with relocating the new sensor. Would have saved me about 3 hours of frustration in a cramped space.
 
Been there too. Throw a duvet over the top of the engine and squeeze your way in. It's a bit of a handful but once in easy enough to get to. My biggest issue was to get it to line up with the shaft on the gear wheel. As it turned out I had to remove the helmet from the drive and insert the shaft from the bottom to locate into the new sensor. Cause of failure appeared to be growth on the underside of the wheel (not visible until dismantled) forcing it upwards hence the shaft was about 2mm too high for the sensor to relocate once the old one had been removed. Remember this if you struggle with relocating the new sensor. Would have saved me about 3 hours of frustration in a cramped space.

Thanks Bruce some good experienced advice there, thinking I might just get a quote for an engineer to do it lol. The duvet is a good idea and should minimise the bruises I always pick up in the engine bay!
 
Bruce was good enough to offer me same advise when changing mine but thankfully the new sensor slid right in. BUT!!

But, it would not fit in with the O-Ring (not supplied, had to order extra), or any other O-ring in my kit. But then I remembered that there wasn't an O-Ring on the one I took out. I nervously installed without the O-Ring and checked that there was no water - thankfully no water ingress! (I tested while static, revving engines, after a run etc.)

While you're at it, make sure to grease the steering while back there (nipple on the port side of each sensor, hard to miss) - I pump this with grease annually until i see grease coming out the stern above the steering helmet (have someone there to shout at you)
 
Bruce was good enough to offer me same advise when changing mine but thankfully the new sensor slid right in. BUT!!

But, it would not fit in with the O-Ring (not supplied, had to order extra), or any other O-ring in my kit. But then I remembered that there wasn't an O-Ring on the one I took out. I nervously installed without the O-Ring and checked that there was no water - thankfully no water ingress! (I tested while static, revving engines, after a run etc.)

While you're at it, make sure to grease the steering while back there (nipple on the port side of each sensor, hard to miss) - I pump this with grease annually until i see grease coming out the stern above the steering helmet (have someone there to shout at you)

Hi Alt, waiting on a quote from my engineer as feeling lazy lol. regarding the grease nipple I noticed this when locating the sensor and would like to grease these points, what grease do you use?
 
Hi Alt, waiting on a quote from my engineer as feeling lazy lol. regarding the grease nipple I noticed this when locating the sensor and would like to grease these points, what grease do you use?

I use a grease gun (few £ from Amazon) with a FLEXIBLE hose at the end. I just use bog standard marine / waterproof grease. Although, i'm in the camp of ANY GREASE IS BETTER THAN NO GREASE.

Here is a random Google link, i'm sure you'd get it in your local motorfactors: https://www.homedepot.com/p/Steel-Core-1-Handed-Pistol-Grip-Air-Grease-Gun-39209/301118242

You mention access is tight (I'm lucky that I could get to mine easy), but this is a job I wouldn't skip over... once you're in only takes 2 mins per engine.
 
A handy idea that worked for me was to have a couple of flexible hoses made up that were about 600mm long with a grease nipple at the end (one per drive). Unscrewed the existing hard to get to nipple on the drive and screwed the hoses in and tie them off near the top of the engine somewhere where they are easy to get to.
 
Ok so engineers quote in at £530 arghhh looks like I'll be giving it a go myself!!

So bit the bullet and bought the sensor £230, clearly I'm running the wrong kind of business, anyway couple of questions guys.

1) Approx. how long should this take to replace?
2) I notice on the new sensor there is a white mark on the plastic body and the metal spinning part I'm assuming I line these up when I install (Instructions that came with it laughable)
3) Do I position the leg fully down then install the sensor and that way its in the correct position and reading correctly?
4) Do you have to calibrate or will it ready correctly if installed correctly?
5) Is this as simple as unplug sensor, remove nut/bolt, remove bracket, remove sensor, line up install new sensor and put back together, then bingo?

Thanks in advance.
 
1) Approx. how long should this take to replace?

Half an hour a piece once you've made room. You may need to remove some piping on top to reach easily. If you struggle to locate them correctly much longer. I really struggled with mine and it took 4 hours total including removing helmet etc to come in from underneath

2) I notice on the new sensor there is a white mark on the plastic body and the metal spinning part I'm assuming I line these up when I install (Instructions that came with it laughable)

try and take off the old sensor at say 0 trim. before locating and tightening down new sensor, wire it up and set to 0. Chances are that you will need to calibrate by loosening helmet rack gearing and adjusting the gear wheel, but you may get lucky

3) Do I position the leg fully down then install the sensor and that way its in the correct position and reading correctly?

see 2
4) Do you have to calibrate or will it ready correctly if installed correctly?

see 2

5) Is this as simple as unplug sensor, remove nut/bolt, remove bracket, remove sensor, line up install new sensor and put back together, then bingo?

Pretty much but like all things boat there is a black tank full of Murphy's just busting to trip you up. But in essence a simple job
 
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BTW, it's a 2 man job. The 2nd man gets to drink tea and call out guage readings and encouragement to you
 
I'm on the phone so short reply but advise above is not quite correct.

You trim the leg down max and apply some pressure (approx 15kg). You want to then fit and hand tighten nut. You then get the 2nd person at the helm to tell you the figure and you get it to match the other. In my case -3

Doing it this way meant I did not have to loosen anything outside ie. Cog / Wheel

I may have been lucky but when I popped mine in it was -5 So I had very little adjusting to do and only took 5 mins to adjust once in.
 
Why would you need to add 15kg of weight to anything? It's on rams. I can understand you wanting to go to an endpoint but not sure that is entirely necessary so long as it's a known point against which to calibrate.

Gear wheel sometimes because in tightening the sensor mine would shift a couple or so points and it's easier to adjust there than faff about
 
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Why would you need to add 15kg of weight to anything? It's on rams. I can understand you wanting to go to an endpoint but not sure that is entirely necessary so long as it's a known point against which to calibrate.

Gear wheel sometimes because in tightening the sensor mine would shift a couple or so points and it's easier to adjust there than faff about

Only going on the advice I received on here previously. Even on rams there may be a miniscule movement so I guess people are just being OCD which I've no problem with.

I disagree 're adjustment....its dead easy (on my boat anyway) to adjust at the sensor but that may be due to the not-so-bad accessibility
 
Not denying what you are saying, just trying to understand the rational. I've only had to do mine once so can only base my experience on that, and although succeeded may not have been by the most efficient means.
 
Not denying what you are saying, just trying to understand the rational. I've only had to do mine once so can only base my experience on that, and although succeeded may not have been by the most efficient means.

Likewise, i've only done mine once too, so not experienced.

I'm not disagreeing with you, when I had a lad lean against the out-drive, it made no difference. I was only following protocol :)

Maybe if they put 7.5KG pressure on the out-drive we'll all be in agreement!
 
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