Volvo D2 75F Waste-gate stuck

[Kuno]

We got a Volvo D2 75F. It’s 3 years old and has around 400 hours. For the first year I could get 2800 rpm under full throttle. Volvo recommends to run the engine wide open every 10 hours to prevent carbon build up in the turbo and waste gate. I noticed that in the second season we only got 2700 rpm. I could not quite figure out why. This fall when I did the oil change I noticed that the 2” hose clamp that holds the rubber hose that connects the turbo out to the engine intake slipped off and therefore would lose some of the Turbo charge. At that time I realized that the Waste gate is firmly stuck. Questions. Does anyone have the same problem? Since everything seams to run fine, would it create problems if I keep running the same way? Is there a way to free the Waste gate without rebuilding the turbo for $2000.

[skipperpete]

Waste gates jam up quite often but usually in the closed position so there should be no loss of turbo boost or efficiency but it would be nice if it worked. For a drop of only 100 rpm at full throttle there could be many things to explore ...starting with the propeller health and working up to fuel filters, air intake filter and engine control cable adjustment.
Hope you find the missing 100rpm

[Kuno]

thanks for the reply. the waste gate is stuck in the closed position. The turbo charge loss is at the flexible rubber connection. I did put the hose clamp back in place but as soon as I go over 2600rpm the hose balloons and pulls the clamp off again. Too much pressure.so basically the rubber hose acts as a waste gate. The question is. 1. will it create problems down the line? 2. is there a way to free the waste gate without pulling everything apart?

[jimbunyard]

Whilst looking for information on the waste gate found this at YBW.com.

https://forums.ybw.com/index.php?thr...-turbo.431360/

"Just had to rebuild my wastegate on my d2-75 turbo caused by a volvo penta casting fault on the exhaust water injection elbow. The bottom fixing point of the casting obstructs the waste gate from opening and requires grinding away if you want the waste gate to ever open. My engine has done less than 300hrs!! It's worth checking all you d2-75 owners, just put your hand under the turbo from the port side and tug the wastegate actuator bar it should move towards you approx 15mm."

[Kuno]

thanks that locks like our situation. I will try to find our how they resolved the problem.

[billknny]

Over boosting from a stuck closed waste gate is NOT a trivial matter. Too high a boost can seriously damage your engine.

It's not just "nice it if works"--it is vital to the longevity of your engine!

Take it to a turbo shop. Have them fix and recalibrate it for you.

[ohthetrees]

Same here. Just bought the boat, and I’m doing all the baseline maintenance. Interesting PO. If it was on a maintenance schedule, he did a great job. If not, just common sense, or noticing things out of place or corroding, he ignored completely. Very by the book, and a few things were in terrible condition.

Anyway, doing a full service of the engine, and the wastegate actuator isn’t moving, at least with hand pressure. I believe the same elbow casting previously discussed is obstructing the wastegate. That assumes the pushrod is supposed to move toward port side when actuating. That isn’t happening, there is a big chunk of casting in the way

Pic 1: from port side, you can see the big chunky attachment point for the elbow.

Pic2: from aft, can see pushrod and actuator. Actuator would have to move left and through casting if I understand correctly.

I’m wondering if Volvo might cover a repair considering I think I can say with some confidence that my waste gate has never once worked.

If they don’t, does anyone have a degree of difficulty/ rough procedure involved with remedying the situation? The pushrod has zero play in it, And I can’t even move it a millimeter, so I assume it is frozen in addition to the casting interference problem. How hard will this be to fix DIY?

My degree of difficulty comfort level: new water pump or alternator: yes, reboring cylinders or new valve seats: no.

Advice appreciated!

[jimbunyard]

Originally Posted by ohthetrees

Same here. Just bought the boat, and I’m doing all the baseline maintenance. Interesting PO. If it was on a maintenance schedule, he did a great job. If not, just common sense, or noticing things out of place or corroding, he ignored completely. Very by the book, and a few things were in terrible condition.

Anyway, doing a full service of the engine, and the wastegate actuator isn’t moving, at least with hand pressure. I believe the same elbow casting previously discussed is obstructing the wastegate. That assumes the pushrod is supposed to move toward port side when actuating. That isn’t happening, there is a big chunk of casting in the way

Pic 1: from port side, you can see the big chunky attachment point for the elbow.

Pic2: from aft, can see pushrod and actuator. Actuator would have to move left and through casting if I understand correctly.

I’m wondering if Volvo might cover a repair considering I think I can say with some confidence that my waste gate has never once worked.

If they don’t, does anyone have a degree of difficulty/ rough procedure involved with remedying the situation? The pushrod has zero play in it, And I can’t even move it a millimeter, so I assume it is frozen in addition to the casting interference problem. How hard will this be to fix DIY?

My degree of difficulty comfort level: new water pump or alternator: yes, reboring cylinders or new valve seats: no.

Advice appreciated!

As far as I can tell, the turbo is supplied integrally with the wastegate from the manufacturer; the exhaust el is added by Volvo in its marinization.

Since the problem is a result of Volvo's engineering or quality control (or lack thereof) common sense would dictate that they should be responsible. Good luck with that, though some with more experience may inform us that there is indeed a bulletin addressing the issue, perhaps even a service recall.

Doesn't look too hard to DIY; mark the offending area with a marks-a-lot, remove 5 bolts #19, bolt #7, hose clamp #23, the not-shown clamp holding the exhaust hose to the exhaust outlet, pry the elbow off.

After making sure there's enough meat to make the 'adjustment', take a 4" grinder and do the business, preferable somewhere that it doesn't matter if you throw ground cast iron all over the place. If you have a die grinder, that would also work, and could possibly be done in place, but...

Dry fit to make sure you have clearance, plus a little more, clean the mating surfaces to metal, install with new gasket 21194801 (34.00 euros!, though they're available aftermarket from an outfit in Oz for 10.00 Aus), and you're done.

Probably easier than changing a water pump, depending on access...

https://www.marinepartseurope.com/en...0-25-6806.aspx

https://www.marineenergy.com.au/prod...et-replacement

[captainjay]

At four hundred hours get new exhaust elbows. Tear down the turbo and clean up the wastegate with acid and a Dremel. You can make it work again. The RPM loss is likely from clogged exhaust elbows.

[SVHarmonie]

Originally Posted by ohthetrees

Same here. Just bought the boat, and I’m doing all the baseline maintenance. Interesting PO. If it was on a maintenance schedule, he did a great job. If not, just common sense, or noticing things out of place or corroding, he ignored completely. Very by the book, and a few things were in terrible condition.

Anyway, doing a full service of the engine, and the wastegate actuator isn’t moving, at least with hand pressure. I believe the same elbow casting previously discussed is obstructing the wastegate. That assumes the pushrod is supposed to move toward port side when actuating. That isn’t happening, there is a big chunk of casting in the way

Pic 1: from port side, you can see the big chunky attachment point for the elbow.

Pic2: from aft, can see pushrod and actuator. Actuator would have to move left and through casting if I understand correctly.

I’m wondering if Volvo might cover a repair considering I think I can say with some confidence that my waste gate has never once worked.

If they don’t, does anyone have a degree of difficulty/ rough procedure involved with remedying the situation? The pushrod has zero play in it, And I can’t even move it a millimeter, so I assume it is frozen in addition to the casting interference problem. How hard will this be to fix DIY?

My degree of difficulty comfort level: new water pump or alternator: yes, reboring cylinders or new valve seats: no.

Advice appreciated!

Before you go ripping into things, but sure you know what "right" is. I have an older Volvo turbo, and the spec for the waste gate movement is 0.3mm. Yes, that's it. About 4 sheets of paper. It might be moving that much and you don't even think you feel anything. You NEED a dial gauge to test it.

Do you have a shop manual? Do you know the spec???? Many of these don't move easily unless disconnected, and that messes up the settings...

The advice above to take it to a turbo shop is well worth doing. A bad turbo can have consequences more serious than just low power.

Turbos are cool things, they let us get a lot of power out of smaller lighter engines, but they require maintenance. They are precision devices with highly precise clearances that require specialized tools to test and balance. Attacking it with an angle grinder is a great way to destroy it.

[a64pilot]

100 RPM is nearly insignificant and can be from wind, or more heavily loaded or a slightly dirty bottom or prop.
I would find out spec for boost and install a gauge and see if I was overboosting, if I wasn’t, then I wouldn’t worry about the wastegate.
However turbos do require maintenance, sort of like injectors, meaning that at some interval they should be removed and sent to a shop. It’s much less expensive to pay for maintenance on a schedule than to buy new turbo’ s.

[jimbunyard]

Did any of you last three posters even read the new post? Do you understand that the question was not from the person who originated the thread?

If not, I'd suggest you reread the new post, and try and provide relevant information to that post, since the OP's has virtually no bearing on O-trees's.

At four hundred hours get new exhaust elbows. Tear down the turbo and clean up the wastegate with acid and a Dremel. You can make it work again. The RPM loss is likely from clogged exhaust elbows.

And you know the new poster has 400 hours how? You must own Volvo stock to recommend sight unseen that O-tree springs 663.00 euro each for new exhaust elbows(?).

Before you go ripping into things, but sure you know what "right" is. I have an older Volvo turbo, and the spec for the waste gate movement is 0.3mm. Yes, that's it. About 4 sheets of paper. It might be moving that much and you don't even think you feel anything. You NEED a dial gauge to test it.

Do you have a shop manual? Do you know the spec???? Many of these don't move easily unless disconnected, and that messes up the settings...

The advice above to take it to a turbo shop is well worth doing. A bad turbo can have consequences more serious than just low power.

Turbos are cool things, they let us get a lot of power out of smaller lighter engines, but they require maintenance. They are precision devices with highly precise clearances that require specialized tools to test and balance. Attacking it with an angle grinder is a great way to destroy it.

And your "older Volvo turbo" and it's (suspect) .3 mm 'movement' (what does that even mean?) matters to the new poster how?

Suggest you look in the manual ( https://www.manualslib.com/products/...5-4009757.html ) to find the 'spec'... except there isn't one, because, as previously advised, the wastegate is supplied integrally with the turbo.

Bringing the turbo to a 'turbo shop' will do nothing to alleviate the problem, which, if you'd actually comprehended the picture (giving the benefit of the doubt that you actually looked at it) O-tree supplied, and had a basic understanding of the operation of the assembly in question, and were conscientous enough to actually research a problem before making grossly simple, non-helpful, so-broad-as-to-be-useless generalizations, you'd already know.

As you'd also know (if you understood the problem) that nobody suggested "attacking it (I assume you mean the holy turbo) with an angle grinder", since the issue is with the 'ear' on the elbow (not the turbo) that the waste gate lever is hitting, as shown in O-tree's picture.

As can be seen in the pictures below (providing the viewer has the visualization skills), the wastegate actuating lever must be able to move past the plane defined by the surface of the discharge flange on the exhaust volute of the turbo. The ear on the exhaust elbow supplied by Volvo obstructs this movement. The fix is to relieve or remove the obstruction.

By the way, the D2-75 is a Shibaura N844L-T, there are pictures of the turbo here that, in conjuction with the exploded drawing previously referenced, (for some) might illustrate the problem being discussed...

https://naplesturbo.com/shop/Turbo_I..._135756190_OEM

...However turbos do require maintenance, sort of like injectors, meaning that at some interval they should be removed and sent to a shop. It’s much less expensive to pay for maintenance on a schedule than to buy new turbo’ s.

Yeah, maybe, especially if you pay Volvo prices. These guys have one delivered for 300 USD.

https://www.dhgate.com/product/rhf4-...BoCFIQQAvD_BwE

Shop rates around here are about 100/hr...

[Kuno]

Thanks Jim, that is good information. I did not know the manufacturer of the turbo. These pictures really help to understand what is happening with the turbo. It is really hard to get under the turbo to get a cleat view. Our boat is in Greece and we are stuck back home in Canada. So as soon as I’m back I will pull the elbow off and replace it with a stainless one. Hopefully I can free up the waste gate and be done with. I will report back in the fall.

[DougR]

Kuno,
Attached are three fotos of the turbo assy. taken with the turbo upside down on the bench. The actuator with its pressure hose running from the compressor side housing, the linkage across to the wastegate lever, and a closeup of the wastegate actuator arm with exhaust elbow in place.

On this particular assembly there is 4mm of travel from rest position until the actuator arm hits the boss on the exhaust elbow, measured at the black dot by the ruler. The internal actuating arm on the wastegate, as seen on the turbo photo supplied by Jim, is about the same length as the external actuating arm, so that means the wastegate itself will lift 4mm off of the bypass opening. Frankly, I don’t know if this 4mm would be enough to allow sufficient bypass to control the max boost.

On the D2-75 the boost spec starts at about 1200 RPM and raises to 8.7 psi @ 2000 RPM, then stays there until 3000RPM where it is 8.8 psi. Not really a lot of boost pressure.

My suggestion, when you get back to the boat, would be to free up the wastegate and make a series of test runs to check the actual boost pressure. You can remove one end of the small hose on the wastegate actuator and insert a T in the line and run the T to a pressure gauge to see what boost you actually have. You might find that with the linkage free the boost is correct. Or it may be that the wastegate lever isn’t moving enough.......

This afternoon I spoke with an old colleague at VP and he didn’t recall any service bulletins about this wastegate issue, but he does specialize in larger h.p. engines and might have missed it. He did offer to research your engine serial number to see if there are any bulletins which apply to it if you can provide the number.

Hope this helps.

[Kuno]

Hi Doug, thanks for the reply. 8.8 psi at 3000rpm is probably measured with the wastegate open. Installing a pressure gauge will probably give me the best information and should be easy to do.
Since I'm not on the boat right now I don't have the serial #. I do have a product # D2-75F 869648 2017 maybe that works to look up the service bulletins.
thanks for the info and pictures.