My TAMD41p-a

[Moses26]

Good day I have 2 TAMD41p-a they have been running fine for the last year I have owned them. The boat sat on the mooring from September till today. I was starting them and using them periodically (when we weren’t on a lockdown) but today wa the first time I was able to go for a good run and I noticed that they would not rev over 2000rpm and large amounts of black smoke would start at 2000rpm.
Turbos are not stuck they spin freely with my fingers.
Just filled the boat up before the run.
up until 2000rpm they run as normal
Under no load they will rev up past 2000 with no problem or smoke.
I’m a mechanic by trade although other than basic maintenance I’ve never worked on these engines in-depth. Ive read many scenarios of possible problems. Im looking for some guidance on where to start looking. Any help you can give me would be appreciated.
Thanks

 

[oldgit]

Before trying to find any complicated problems.
99% it will be ..............
A/ Dirty bottom. Weed and Slime.
B/ Props . Usually barnycules.
C /Clogged primary and/or secondary fuel filters.
D/ Air filters.
It does not take much fouling to slow down the boat and produce a nice coating of black soot on stern . Just because very little fouling is visible at waterline does not mean there is not sufficient underneath to cause the smoke.
Most boats have not moved for 12 months.or more.

 

[Moses26]

Hello thanks for your reply the bottom is not bad and neither the props or running gear my problem is not lack of speed the engine stops climbing in revs once it hits 2000rpm the further you push the throttle the more black smoke comes out.
Air filters are good I ran it without them for a bit to make sure that was not the problem.
I will try changing the fuel filter elements and see if that helps but the amount of smoke that comes out the exhaust tells me that I have excessive Unburnt fuel or lack of air.
my other problem is there are no parts suppliers locally so I have to import everything andshipping and duty fees are huge.

 

[BruceK]

I agree with OG. Despite you saying

the bottom is not bad and neither the props or running gear

it really doesnt take much to produce what you are experiencing. Have you had the boat out and inspected? Otherwise black smoke would as you correctly point out seem to be a deficit of charged air to fueling mix. Have you put a boost pressure gauge on to see you are making the required boost?

 

[Moses26]

I agree with OG. Despite you saying

it really doesnt take much to produce what you are experiencing. Have you had the boat out and inspected? Otherwise black smoke would as you correctly point out seem to be a deficit of charged air to fueling mix. Have you put a boost pressure gauge on to see you are making the required boost?

I have not tried a boost gauge yet I will definitely try that as soon as I can get my hands on one.
To pull boats here is very expensive most people get bottom cleaned in the water and only come out once a year for maintenance.
thanks for your comments and suggestions!

 

[Jamie Dundee]

Unlikely both engines will have an identical problem. As others have said bottom/prop fouling the most likely explanation. Do they rev up ok out of gear?

 

[oldgit]

Unlikely both engines will have an identical problem. As others have said bottom/prop fouling the most likely explanation. Do they rev up ok out of gear?

"Under no load they will rev up past 2000 with no problem or smoke. "

It does not take much fouling to slow boat down.

My boat prior to going on our drying blocks at WOT gave 17 -18 knots .Max revs 2900- 3000 both engines.
When hull exposed, not much at all visible, light coat of slime , you could count the small number of barnycules.
Jet wash and A/F. Next trip out 24 knots and 3600 on both engines.

Princess 41.
On a club cruise .
Flat out max of 10 knots masses of black smoke, see him trailing behind from miles away
On arrival at destination, diver summoned .
Both propellers smothered with big barnycules.
Props scraped off. 22 knots achieved on return journey..