Need Some Feedback re: Mechanic experience

[Solstice]

Would appreciate some feedback on my recent experience. Not feeling real good about it, but perhaps overthinking. Some background:
I have a new Yanmar 3YM30 and am 3 weeks away from warranty expiring. I typically do all my own engine work and am rather familiar with these engines. During warranty periods with Yanmar, I know to be meticulous about following their requirements (from experience). So I had a Yanmar certified mechanic come to the boat on Friday to do a Intake/exhaust valve check (per the manual), check alignment and look into whether I had a tach issue or a governor issue as my boat idles at 4100 (since about hour 20--currenty have 58 hours).

Amazingly there are only a couple of authorized Yanmar mechanics who will travel locally. Tragically, the more well known of the two unexpectedly passed away a couple of weeks ago. So I scheduled the other--couldn't find any references good or bad, but didn't have much choice.

Here is my concern, of the 3 items I asked to have checked, here is what happened:

--my CB was sloppy and I blamed it on myself since I should have checked alignment after taking delivery after the initial adjustment by the dealer. I got lazy and didn't. The mechanic checked and said it was within .003; but I'm not sure--again my bad because I was on the boat with him, but did not insist on taking a look myself. I'll take him at his word, but a bent shaft is possible, but unlikely--very short shaft that comes out of a skeg, no strut.

--valve adjustment--mechanic did not have service manual with him and mine was on my computer and not with me. Needless to say, he did not know what it should be. To his credit, he had a call into Mack Boring before he showed up and called them and spoke with them while on the boat. In the meantime, he opened it up and said 'they were loose, marked before he started and then tightened. However, he did not have the correct measurement ( .15-.25mm) before he started. This is what bothers me.

--RPM--checked the tach and found it to be within 25-50 rpm off, basically accurate. We ran it in nuetral and verified tach to be accurate at a range of throttle. Tach measurement showed 3950 at WOT. Mechanic called M-B again and discussed. They said 300-350 isn't that unusual with no load. Mechanic wanted to test under load and said at the dock with docklines would not be an accurate guage. Offered to do a sea trial with me (again to his credit), but I chose not to. I agreed that next time I go out, I will test under load. However, I know from experience that the rpms are high under load as well. We discussed prop pitch etc and he wrote down model #, pitch etc. I agreed to call him back if I confirmed high rpm under load. So he wasn't willing to adjust the governor.

Bottom line: of the 3 items looked at, I don't feel like we accomplished much and may have adversely affected valve clearance. The advice of get another mechanic is a problem at the moment (see above) and I'm wondering if I am needlessly worrying? Sorry for the long post, but would love to hear from others on this. Thanks in advance....

 

[kenn]

Not 100% clear on the problems...

1) you say the cutless bearing is sloppy... are there discernable issues with the driveline (vibration, roughness, shaking/shuddering, rattling) ? You say the mechanic claimed coupling alignment is within .003" which is ok. Worst case - if there are discernable problems, remove prop shaft and check it for runout, replace the cutless bearing, reassemble and check alignment.

2) Did he not get that info on the phone? if the mechanic didn't have the spec at the time, did he tell you what value he did align to? Assuming he had general diesel experience, I'd expect he'd know the difference between ok and loose. Worst-case - if you want certainty, either you or a mechanic will need to check the valve clearance again.

3) shoulda done that sea trial, eh? It's now up to you to get that info and if you find the engine top speed is too high, then you need to have the governor adjusted.

I'm not a mechanic, but I worked as a helper for one a couple years ago. No disrespect intended, but as a concerned customer, it sounds like you didn't prepare yourself or the boat as much as you could have to get the best value out of the mechanic's visit.

No crime has been committed, your engine is apparently not showing symptoms of a serious issue, so you have the luxury of time to get your uncertainties cleared up. Happy sailing!

 

[Solstice]

Not 100% clear on the problems...

1) you say the cutless bearing is sloppy... are there discernable issues with the driveline (vibration, roughness, shaking/shuddering, rattling) ? You say the mechanic claimed coupling alignment is within .003" which is ok. Worst case - if there are discernable problems, remove prop shaft and check it for runout, replace the cutless bearing, reassemble and check alignment.



2) Did he not get that info on the phone? if the mechanic didn't have the spec at the time, did he tell you what value he did align to? Assuming he had general diesel experience, I'd expect he'd know the difference between ok and loose. Worst-case - if you want certainty, either you or a mechanic will need to check the valve clearance again.

3) shoulda done that sea trial, eh? It's now up to you to get that info and if you find the engine top speed is too high, then you need to have the governor adjusted.

I'm not a mechanic, but I worked as a helper for one a couple years ago. No disrespect intended, but as a concerned customer, it sounds like you didn't prepare yourself or the boat as much as you could have to get the best value out of the mechanic's visit.

No crime has been committed, your engine is apparently not showing symptoms of a serious issue, so you have the luxury of time to get your uncertainties cleared up. Happy sailing!

Kenn,

Thx for the reply. No disrespect taken--where I wasn't prepared was in not having him show me what his measurements were. My CB was a bit sloppy this spring, so the alignment is the first place to look--especially given that it is a new boat and it wasn't aligned after it settled; that was my fault. I know i should have done it a couple of weeks after getting the boat. No vibration or ill effects yet, but the CB being a bit sloppy tells me there is a problem somewhere.

As far as the tolerance, yes he should have told me what he set it to, but didn't and again my fault for not asking him to show me. He did not get the answer on the phone. It was one of those things where I knew as soon as he left that I should have asked him to show me. Where I was unprepared in this case was my shop manual arrived 2 days after this mechanic visit.

Finally, I opted not to do the sea trial because I didn't want to ring up the hours if I end up hiring someone else (if I can find someone else). We agreed that when I took the boat out next, I would check it both at the tach and with an IR at the engine. Turns out the governor is right on and it maxes out at 3650 under load, and knowing that my tach is off by that much, I'm now comfortable that that governor is set as it should be.

At this point I will check the alignment myself and will probably have someone else check the tolerance. Again, with no disrespect, shouldn't the mechanic have come prepared with the proper specs and know what the no load WOT should be? I guess that's why I have questions about everything else.

 

[Stu Jackson]

Hi,

Has it really been almost a year already? Time flies...

Question: what made you think your CB was sloppy in the first place? Were you out of the water or did you giggle it behind the engine? Reason I ask is that I would figure with your configuration (no strut) that you should be able to easily check that before alignment. Those old tricks of using string to hold the shaft in the middle of the sterrn tube should work for you. Then check the engine alignment.

Any reason to think your shaft is bent? Hit anything?

I once had a friend call and said he had a lot of squeaking underneath his C34 after he had a new CB installed, and what do I think it is. I asked him he'd run aground. "How did you know!?!" Sand in the CB...

I would think you could check the true of the shaft by decoupling and turning it. Or do you not have the room?

Have you asked on the C355 board?

Glad you're enjoying your new boat.

All the best,

Stu

PS - Yeah, it's a bummer when you start having bad vibes. Take a deep breath, 'cuz YOU are gonna figure it out. That's why so many of us think "diesel mechanic" is an oxymoron, except for the good guys Roger found on his way north.

 

[kenn]

At this point I will check the alignment myself and will probably have someone else check the tolerance. Again, with no disrespect, shouldn't the mechanic have come prepared with the proper specs and know what the no load WOT should be? I guess that's why I have questions about everything else.

Fair question, and the only reply I have is that even the good guys occasionally have bad days. Yes the mechanic should have arrived with all necessary info, and with all this stuff digitized, you'd think every mechanic would carry a laptop with all their manuals.

But the operative phrase is "caveat emptor" and as Stu and many others will stress, no-one's as interested in your boat as you are. So it's always in your best interest to be the best-prepared guy, with your own manual available, and with a sharp eye and thoughtful questions.

Nothing in your description seemed to indicate that the mechanic was flat-out careless or incompetent... did you see enough potential to forge a good relationship with him, as opposed to trying again with someone else?

 

[Solstice]

Hi,

Has it really been almost a year already? Time flies...

Question: what made you think your CB was sloppy in the first place? Were you out of the water or did you giggle it behind the engine? Reason I ask is that I would figure with your configuration (no strut) that you should be able to easily check that before alignment. Those old tricks of using string to hold the shaft in the middle of the sterrn tube should work for you. Then check the engine alignment.

Any reason to think your shaft is bent? Hit anything?

I once had a friend call and said he had a lot of squeaking underneath his C34 after he had a new CB installed, and what do I think it is. I asked him he'd run aground. "How did you know!?!" Sand in the CB...

I would think you could check the true of the shaft by decoupling and turning it. Or do you not have the room?

Have you asked on the C355 board?

Glad you're enjoying your new boat.

All the best,

Stu

PS - Yeah, it's a bummer when you start having bad vibes. Take a deep breath, 'cuz YOU are gonna figure it out. That's why so many of us think "diesel mechanic" is an oxymoron, except for the good guys Roger found on his way north.

Thx Stu. When the boat was on the hard this winter I found the CB to have enough movement (vertical) where I was on the edge of replacement--and decided it wasn't enough to do the job this spring. However I wanted to address whatever caused the wear. Since I should have checked alignment after the initial commissioning, this seems like the logical place.

Haven't hit anything and no vibration or shaft wobble. As you say, with a short shaft and no strut, there is no chance of shaft whip. The only other possibilities are the shaft came from the factory not true or there is a coupling issue. But since I am not experiencing any real issues, need to go back to alignment before I start taking the next steps.
I guess the point of my original post was the 'bad vibes' as you so aptly put it, not so much the issues I wanted address--as you say I will figure it out as I am a DIYer. I guess I would say it was the mechanic who wasn't properly prepared and that is what bothered me.
The 355 board activity is a bit thin (as you see on the 34 forum so for now I rely on the good folks on these great forums...