PDQ OWNERS FORUM

Duane, have you (or anyone else) ever done this turbocharger “washing” process on your boat? If so, did it improve performance?

hi mac,

i did that years ago and also a variation. can't say i saw any major difference. with that said, it was when boat was fairly new. if i did now it might make a noticeable difference.

Have you ever asked a Yanmar tech/dealer if they use this technique? I asked ours and they said the NEVER do this. They prefer to dismantle it, clean it properly and replace whatever gaskets need replacing. They say it is a fairly tricky, complex task and advise again the quick "wash" concept.

the variation i did was take an artist brush and lacquer thinner to clean the turbo blades. it cleaned up perfectly but as i said didn't seem to make much difference. also don't forget turbo performance starts at the other end. if the exhaust end gets dirty, it probably matters more

Mac,

Yes, I have done it, but I never let my turbo blades get dirty, so the washing is more preventative. I have heard some others who had not done it for a very long time say it did help to get more RPM at the top end.

So, what do you do to maintain your turbo blades?

So, what do you do to maintain your turbo blades?

There is another recent thread in which I posted the instructions from the Yanmar Operators Manual. The mechanic might have good reason for not believing the Yanmar folks, but I follow the instructions.

Duane, can you remember the topic name? I have searched and did not find it

mac,

isn't it explained in the diagram in the first page of this thread?

Yes, it was exactly THIS thread but on page 1. Sorry for misdirecting you.

Got it. thanks.

I did it on my 75's. They don't have an after cooler. One of the turbo's had been sticking a little and not spinning freely. It did fix the problem.

A couple of months ago, I had an exhaust leak between the turbo and a spacer that is between the exhaust elbow and the turbo. I had to take the turbo off to do the repairs. You might be surprised how dirty it was on both the intake and exhaust side. I think part of the reason the intake side gets so dirty is the blow by from the crankcase ventilation hose from the valve cover to the intake. I gave it a thorough cleaning while it was off.

Alan

So here’s a conundrum….I see my own post here from a few years ago claiming our boat was running great and achieving 3,800@WOT with 15.5” pitch three blade propellers. It was, but now it doesn’t! Exhaust system cleaned, turbos cleaned, valves adjusted and injectors removed, cleaned and tested. Had props off and “tuned” by 0.06”. Now I have had two prop shops calculate 12.5” to 13.0” as the ideal prop pitch for the boat which corresponds to what most folks have written here. I’ve been told it’s possible the props on the boat are not those I had tuned (will check in a day or two), but in the meantime I am completely befuddled why performance has dropped off. Motors start and run great so next step is to re-prop per the calculations, but that feels like giving up!

As an aside, if I am going to re-prop, I’m thinking about 4-blade props. I know the pros….any cons? What pitch and diameter are some of you running with a 4-blade prop. I know prop shop can calculate, but wondering what others are actually running.