Reply
 
Thread Tools Display Modes
 
Old 06-28-2016, 04:32 PM   #1
Veteran Member
 
City: White Rock
Country: Canada
Vessel Name: Mojo
Vessel Model: Tollycraft 34 tricabin
Join Date: Aug 2013
Posts: 49
6bta 5.9 turbo

Low hour engines
Would black soot and small amount of oil be an issue
I'm looking at why my 3788 only pulls 2200 rpm at wot
I've looked at all the other possible issues
Attached Thumbnails
Click image for larger version

Name:	20160628_125749.jpg
Views:	103
Size:	130.9 KB
ID:	53591  
__________________
Advertisement

yoeman is offline   Reply With Quote
Old 06-28-2016, 05:28 PM   #2
Guru
 
djmarchand's Avatar
 
City: East Greenwich Yacht Club, RI
Country: USA
Vessel Name: Bella
Vessel Model: Mainship Pilot 34
Join Date: Aug 2012
Posts: 2,484
2,200 rpm at wot vs 2,600, 2,800 rpm or 3,000 rpm rated (depending on model) is way over propped and you are damaging your engine. Not enough information in your post to comment further. I suspect that you need a complete servicing of the raw water and air cooler system before going further.


David
__________________

djmarchand is offline   Reply With Quote
Old 06-28-2016, 05:31 PM   #3
Senior Member
 
tadhana's Avatar
 
City: New England to Florida
Country: USA EAST
Vessel Name: Tadhana
Vessel Model: Helmsman 38 Pilothouse
Join Date: Jul 2011
Posts: 426
The crank case breather has a check valve. sometimes they stick open and then you get extra oil into the air intake, and you may even see oil dripping out of the air sep.
tadhana is offline   Reply With Quote
Old 06-28-2016, 05:38 PM   #4
Guru
 
City: Northport
Country: USA
Join Date: Aug 2015
Posts: 536
There was a lot of information and ideas thrown around on your last recent post on this issue and I think the better question is this...


What is the possibility that both turbo's have the exact same problem at the exact same time?


"Would black soot and small amount of oil be an issue"
To answer this question with the information posted and just this one picture I would say these look very typical of many turbo's I have seen in various Bayliners and Sea Rays. Can you get a boost reading even with a temporary gage?
smitty477 is offline   Reply With Quote
Old 06-28-2016, 06:51 PM   #5
Veteran Member
 
City: White Rock
Country: Canada
Vessel Name: Mojo
Vessel Model: Tollycraft 34 tricabin
Join Date: Aug 2013
Posts: 49
Quote:
Originally Posted by tadhana View Post
The crank case breather has a check valve. sometimes they stick open and then you get extra oil into the air intake, and you may even see oil dripping out of the air sep.
I added the pictures and did have another post with more info on the low power
I was told that $1700 was the cost to rebuild the one turbo
So don't want to make the mistake
Props are clean
yoeman is offline   Reply With Quote
Old 06-28-2016, 10:21 PM   #6
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 3,296
When was the last time the engines made their rated rpm?

What has changed since then?
Ski in NC is online now   Reply With Quote
Old 06-29-2016, 12:06 AM   #7
TF Site Team
 
Baker's Avatar
 
City: League City, Tx
Country: Texas
Vessel Model: Carver 356
Join Date: Oct 2007
Posts: 5,406
I hate to say this but many times this is a mental issue. We chase problems down the wrong rabbit hole while totally ignoring advice given. I see it over and over and over. People keep trying to bang you over the head with the most likely solution but you are too far down the wrong path to listen. YOU ARE LIKELY OVERPROPPED!!!! I know of a person that chased every possible solution expect the one that was causing the problem....right up until the point where holes were burned into the pistons. Listen up!!!!! When people like Ski say something....it should be like EF Hutton!!!!!
__________________
Prairie 29...Perkins 4236...Sold
Mainship Pilot 30...Yanmar 4LHA-STP...Sold
Carver 356...T-Cummins 330B
Baker is offline   Reply With Quote
Old 06-29-2016, 06:22 AM   #8
Guru
 
City: Northport
Country: USA
Join Date: Aug 2015
Posts: 536
"I hate to say this but many times this is a mental issue. We chase problems down the wrong rabbit hole while totally ignoring advice given. I see it over and over and over. People keep trying to bang you over the head with the most likely solution but you are too far down the wrong path to listen. YOU ARE LIKELY OVERPROPPED!!!! I know of a person that chased every possible solution expect the one that was causing the problem....right up until the point where holes were burned into the pistons. Listen up!!!!! When people like Ski say something....it should be like EF Hutton!!!!!"


Baker has a great summary posted.
If you want to hear a different suggestion here I would suggest that you somehow secure some additional information so that folks are not attempting to diagnose an issue from one picture.
Things like this....
- What is the boost readings at various rpm from 1800 to max?
- Do your trim tabs full work? (that boat needs max tabs to reach planning angles)
- What are your curremt prop specs? D X P X number of blades and material)
- What are your trans ratios?
- When was the last time your boat achieved planning speeds and correct rpm?
- Over how long of a time period did this problem happen?
- What other symptoms do you have? (soot, temps, high idle rpm readings, etc)
smitty477 is offline   Reply With Quote
Old 06-29-2016, 07:59 AM   #9
Guru
 
Join Date: Oct 2007
Posts: 607
Nobody mentioned a fouled prop!! Dramatic impact on WOT!!
Assuming (not clear from posting) that engine did reach WOT in the past and prop has not been changed, then how could engine be overpropped??
Chrisjs is offline   Reply With Quote
Old 06-29-2016, 08:41 AM   #10
Guru
 
City: Northport
Country: USA
Join Date: Aug 2015
Posts: 536
"Nobody mentioned a fouled prop!! Dramatic impact on WOT!!
Assuming (not clear from posting) that engine did reach WOT in the past and prop has not been changed, then how could engine be overpropped??"


You would have had to read the other post from a couple of days ago. If you so desire the link is right here.....


Bayliner 3788 Low rpm
smitty477 is offline   Reply With Quote
Old 06-29-2016, 10:38 AM   #11
TF Site Team
 
Baker's Avatar
 
City: League City, Tx
Country: Texas
Vessel Model: Carver 356
Join Date: Oct 2007
Posts: 5,406
Quote:
Originally Posted by Chrisjs View Post
Nobody mentioned a fouled prop!! Dramatic impact on WOT!!
Assuming (not clear from posting) that engine did reach WOT in the past and prop has not been changed, then how could engine be overpropped??
I guess the proper term here would be overloaded. We still do not know if it used to reach WOT and now it does not. But you can overload a boat that was previously perform well by a fouled bottom or fouled props.

Another thing not discussed is while it may appear both engines are suffering the same problem, could there be an engine that is malfunctioning(ie turbo) and causing the other engine to be overloaded??? I think I read a case on boat diesel where the HEALTHY engine was belching smoke because it turns out, it was the only one trying to do work while the other engine had a slipping transmission or something like that. Bottom line, a fault of one engine made it appear that the good engine was faulty.
__________________
Prairie 29...Perkins 4236...Sold
Mainship Pilot 30...Yanmar 4LHA-STP...Sold
Carver 356...T-Cummins 330B
Baker is offline   Reply With Quote
Old 06-29-2016, 11:03 AM   #12
Guru
 
City: Northport
Country: USA
Join Date: Aug 2015
Posts: 536
"Assuming (not clear from posting) that engine did reach WOT in the past and prop has not been changed, then how could engine be overpropped??""


The OP - Yoeman is posting on the BOC as well as the trawler forum.
I just saw a few posts over there that indicates he has bought at least 2 maybe more boats very recently through an auction with no background on the boats and no sea trails.
Based upon that and the previous posts here I would guess that we have all the information he has so far on this new to him boat.
When and if any additional data become available I am sure folks here could narrow this down quickly - until then it is just a wild ass guess.
smitty477 is offline   Reply With Quote
Old 06-29-2016, 02:09 PM   #13
Guru
 
City: gulf coast
Country: pinellas
Join Date: Jun 2014
Posts: 2,013
not again?????
bayview is offline   Reply With Quote
Old 06-29-2016, 02:21 PM   #14
Guru
 
timjet's Avatar
 
Join Date: Apr 2009
Posts: 1,905
Not enough info. 2200 WOT is so far below rated WOT that it's hard to know where to start.

Read David's and Ski's post again, they are both experts and will save you much time and money if you listen.

And read Bakers post again. I could be and probably am the guy Baker refereed to as chasing the rat down the wrong hole. I was overpropped and got the reman to prove it.
It probably is the obvious problem even if you don't want to believe it.
__________________
Tim
Tampa Bay
Carver 355 ACMY Twin Cummins Diesels Sold
timjet is offline   Reply With Quote
Old 07-01-2016, 05:39 AM   #15
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 15,601
Perhaps the PO installed a set of cruising props and WOT cruising is no longer contemplated?

Black soot is the usual sign of a prop being run at an RPM too great for it.

Try 1800RPM or so to see if she runs well there as that probably was the goal.

Even 15-1600 might be a great cruise.

Not every owner wants to tow water skiers.
FF is offline   Reply With Quote
Old 07-01-2016, 12:15 PM   #16
Senior Member
 
kapnd's Avatar
 
City: hawaii
Country: usa
Vessel Name: #31
Vessel Model: ex-Navy MUB 50 fish/cruise
Join Date: Aug 2013
Posts: 179
I concur with FF, however if overpropped is going to be considered normal, and the engine run at reduced rpm, the throttle should be limited to eliminate the possibility of overstressing the engine.
The seller should also disclose such information upfront.
I'm curious as to what max rpm is out of gear?
Envirovent is an aftermarket blowby separator system from Seaboard Marine that works well for the Cummins B's and C's, worth looking into.
kapnd is offline   Reply With Quote
Old 07-01-2016, 05:33 PM   #17
Veteran Member
 
City: Terrell
Country: USA
Vessel Name: Willie Pearl
Vessel Model: Seahorse 54 Sedan
Join Date: Mar 2016
Posts: 71
What is the EGT.......was mentioned about over proped or fouled if EGT's are higher 1000 1300 I agree with proper symptom
pearlwindham is offline   Reply With Quote
Old 07-04-2016, 09:50 PM   #18
Guru
 
C lectric's Avatar
 
City: Gibsons, B.C.
Country: Canada
Join Date: Oct 2007
Posts: 1,606
Quote:
Originally Posted by yoeman View Post
I added the pictures and did have another post with more info on the low power
I was told that $1700 was the cost to rebuild the one turbo
So don't want to make the mistake
Props are clean

So put a link into your post so we can read it without a great pia search. I tried a search but no dice.
Help us help you. Or repost all the other info.
I agree, no where enough info to hazard any kind of reasonable suggestions.
C lectric is offline   Reply With Quote
Old 07-07-2016, 09:10 PM   #19
Guru
 
C lectric's Avatar
 
City: Gibsons, B.C.
Country: Canada
Join Date: Oct 2007
Posts: 1,606
I suspect this a dead issue since the O.P. hasn,t replied but

SOOT

Yes soot, if it is indeed soot, is an issue. That is most likley an exhaust leak. Soot from that will quickly plug air filters. Engines are excellent vacuum cleaners. A plugged air filter can cause poor performance and often heavy black smoke at the transom.

Soot will also make a big mess. You may have to watch while the boat is run to locate exactly where it is coming from. Soot often leaves telltale blackening where it leaks from so you may find the leak with a close examination of the entire exhaust .

Edit. Sooting in the engine compartment is what I was referring to.
C lectric is offline   Reply With Quote
Old 07-07-2016, 10:05 PM   #20
Guru
 
Hawgwash's Avatar
 
City: Sidney
Country: Canada
Join Date: Feb 2015
Posts: 2,143
If he's not coming back, I don't feel bad about a sidebar...what are "spooling" and "droop."?
__________________

Hawgwash is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 08:54 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012