Jamie Dundee
Well-known member
I’d be interested in the result of the opposite scenario, run the ’good’ engine on full with the ‘faulty’ engine in neutral.
D1-30 cannot get above 2000rpm and its not the prop or fuel
- Thread starter Gavdog
- Start date
Gavdog
New member
Hmmm, I've never heard of this before but this certainly sounds plausible. I've noticed sometimes it gets to 2300rpm on startup when I first move into gear but then it drops slowly down to 2000rpm and then that's it so your clutch idea is definitely a possible. Only problem is, how to test that theory without having to buy/install new sail drive or clutch pack? Any thoughts on that? Thanks heaps
Gavdog
New member
Definitely not tacho. Speed is significantly slower on port engine. Thanks though.
Gavdog
New member
Doesn't change anything. Regardless of whether boat is at speed or not using starboard engine, the port stays at 2000rpm. Cheers
Gavdog
New member
Ps, can you please confirm which is the hose location of the one you're meaning. Is it the massive black one that leads out of the boat or a different one? I'll try to go through all the hoses in any case when back on the boat. Cheers
Gavdog
New member
Can it be the governor though if it still revs fine out of gear? Cheers
Cariadco
Active member
Fuel Pump/Governor.
When loaded, it doesn't supply enough fuel, hence the low revs.
Unloaded, no probs, it'll rev fine.
Regards.
When loaded, it doesn't supply enough fuel, hence the low revs.
Unloaded, no probs, it'll rev fine.
Regards.
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bignick
Active member
Do you get black smoke when at wide open throttle?
scottie
Well-known member
Definitely sounds like a fuel problem from your answers either lack of fuel to engine which should be checked with independent temp supply possible air in supply, line blockage breather blockage then if still faulty check for faulty fuel pumps including lift then governor
scottie
Well-known member
Remember that any dismantling of the fuel lines increases likelyhood of Leak so plenty of new washers in case
Talulah
Well-known member
I’ve only just seen this thread so apologies if I’ve missed the bits about the prop.
If the prop is a feathering prop it’s possible the stop inside the hub has broken. Depending where it is jammed will affect the pitch of the prop. It’s possible the pitch has now significantly increased and the engine can no longer turn it at the higher revs.
If the prop is a feathering prop it’s possible the stop inside the hub has broken. Depending where it is jammed will affect the pitch of the prop. It’s possible the pitch has now significantly increased and the engine can no longer turn it at the higher revs.
bignick
Active member
Hi Gavdog,
I just re-read all your earlier replies, and noticed that you said that it revs fine to 3000 RP,M in neutral AND REVERSE. This is quite important, so please double check.
Can you confirm that you’re getting full astern thrust and the stopping power is similar between port and on starboard engines?
If they are similar then it is more likely to be something in the drivetrain. This isn’t 100% certain, because fwd/reverse gearbox ratios are often different and prop efficiency can vary, but is a good indicator. if you’re getting similar engine performance P & S when under load in reverse, and completely different when running ahead RPM, then it looks more like a drivetrain issue.
I can’t find a reply about what drivetrain these engines are connected to, but I’m guessing that since you’re talking about a pair of D1-30s, you’re talking about a cat, not a MoBo. Correct? Saildeives? If so, then I’d start with the clutch pack in the gearbox, as mentioned in post #37 (it’s quite a common thing to fail on high hours saildrives).
This is an expensive fix though, so if you can swap over the exhaust hoses between P&S engines to eliminate exhaust back pressure issues, which is a job you could do yourself, then I’d try that first. It would be criminal to strip a saildrive and replace a clutch pack and find later it was a £50 hose.
PS, to test astern thrust, you’re better doing a dock pull , ie. Build up astern RPM gradually with the boat tied securely alongside the dock. If you just give it loads of astern RPM when you’re moving then you will most likely cause cavitation, which won’t generate the same engine load and won’t prove anything.
cheers,
nick
I just re-read all your earlier replies, and noticed that you said that it revs fine to 3000 RP,M in neutral AND REVERSE. This is quite important, so please double check.
Can you confirm that you’re getting full astern thrust and the stopping power is similar between port and on starboard engines?
If they are similar then it is more likely to be something in the drivetrain. This isn’t 100% certain, because fwd/reverse gearbox ratios are often different and prop efficiency can vary, but is a good indicator. if you’re getting similar engine performance P & S when under load in reverse, and completely different when running ahead RPM, then it looks more like a drivetrain issue.
I can’t find a reply about what drivetrain these engines are connected to, but I’m guessing that since you’re talking about a pair of D1-30s, you’re talking about a cat, not a MoBo. Correct? Saildeives? If so, then I’d start with the clutch pack in the gearbox, as mentioned in post #37 (it’s quite a common thing to fail on high hours saildrives).
This is an expensive fix though, so if you can swap over the exhaust hoses between P&S engines to eliminate exhaust back pressure issues, which is a job you could do yourself, then I’d try that first. It would be criminal to strip a saildrive and replace a clutch pack and find later it was a £50 hose.
PS, to test astern thrust, you’re better doing a dock pull , ie. Build up astern RPM gradually with the boat tied securely alongside the dock. If you just give it loads of astern RPM when you’re moving then you will most likely cause cavitation, which won’t generate the same engine load and won’t prove anything.
cheers,
nick
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neilf39
Active member
High pressure pump to injectors starting to fail? If it's failing then maybe not pumping enough fuel when engine under load? Partial blockage somewhere in high pressure lines?
Bilgediver
Well-known member
The governor does not have to apply much fuel for neutral running. so part of the governor is fine. However to get enough fuel delivered for full load at full revs the governor has to move the components a lot further and it is possible that it is under these conditions things go wrong. and it is unable to move the fuel pump rack to full delivery and as insufficient fuel being delivered the engine slows down
Gavdog
New member
Definitely not the fuel pump. I replaced that. Also bypassed using tote tank and exactly same revs. Could be governor though but not sure how to check. Thanks!
Gavdog
New member
Yes that clutch seems definitive plausible but like you say I've got to eliminate everything else first. I've got to reassemble before I can rest revs again on my mooring but yes I'm sure we got to 3000 in reverse at the marina (just waiting on new thermostat to arrive from overseas before I reassemble and refill coolant). I'll switch the hoses like you say too. Cheers, will let you know how I get on. Everything is slow in this process as it is winter and it's on a mooring so getting out on fine day when not working is hard to come by
Gavdog
New member
OK, I definitely think governor is worth investigating again. I'll have to do some forum hunting to see how to check that though. I thought the mechanic had said that he thought governor was fine but is there a way to tell that easily?
Gavdog
New member
Hmmm, interesting idea. How do I check that one? Thanks!
scottie
Well-known member
Try a temporary fuel line first
clean (spotless ) fuel straight to lift pump
this will elimnate supply shortage possibly
clean (spotless ) fuel straight to lift pump
this will elimnate supply shortage possibly
Cariadco
Active member
Sorry, I did mean the high pressure pump, not the lift pump.