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KAD42 Problem with cutover between Super Charger amp Turbo

bobfisco

New member
"I have sealine 36 with twin V

"I have sealine 36 with twin Volvo Penta KAD42's. The boat wont go on the plane as the port engine keeps "holding back" when the super charger cuts out & hands over to the Turbo Charger.Ive read that the supercharger is electronicly operated so as to cut in and out according to rpm. Have checked fuel & filters, there are no air leaks, the turbo spins freely and is not pumping out smoke.When the engine is not underload she revs fine, but when under load she wont go past the point where turbo takes over. Any suggestions please as im running out of ideas?"
 
"Hi Andre,
All the supercharg


"Hi Andre,
All the supercharger does is help the turbo spool up quicker to produce maximum boost.The fact that it cuts in and out is a red herring. The problem could be in the turbo itself or at the injection pump.You need to connect a pressure gauge to the inlet manifold to see what pressure is generated,preferably without the supercharger. Disconnect wiring to clutch assy. Do a acceleration test.Port engine will still accelerate but slower.If not enough boost get turbo tested/checked.
Other problem could be the boost compensation pod on the top of the pump. This allows more fuel to be added as boost increases and is directly linked to the inlet manifold and or turbo.If the turbo checks out fine, get the pump checked.Also check the supercharger clutch assy. They collapse fairly regularly.
Finally, how clean is your hull?
Hope this helps."
 
"Andrea,
Do you have electric


"Andrea,
Do you have electrical controls to your engines?, have you calibrated?
Make sure you get full trottle on the engine, check the wire and make sure you have 100% full trottle at the diesel pump."
 
"Hi Martin, yes i do have elec

"Hi Martin, yes i do have electrical controls, not the new type but the type that run to a servo which then pulls/cable. I have changed he cables but had the problem both pre & post change. If this was the problem as you suggest, would the engine not rev through its rev range when in neutral which it does? I hadnt considered this option at all, i think you might have something. I guess i could compare the cable travel between the 2 engines when under way ?"
 
"Hi Andre.
Yes, the engine wi


"Hi Andre.
Yes, the engine will rev up to max rpm with very low trottle without any load.
I think you have to check the controlls and calibrate them, this is a rather common problem, I had a customer bought a almost new 35 feet boat with 2 KAD32, the boat only did 9 knots on full trottle, so he manage to reduced the price heavily, it took me 10 min to calibrate the controlls, after this 33 knots!
My suggestion is that you pull full trottle on your shifts, then check on the engine to make 100% sure you have full trottle on the diesel pump.
If you have some friend who can drive the boat, you can manually push the trottle on the engine when you have full trottle to see if you get more rpm, then you have found the problem.
Dont forget to bring somethings for your ears, the engines makes alot of noice!
Let me know the result."
 
"Martin Your A Genius! Sorry i

"Martin Your A Genius! Sorry i havent come back to you, boat was launched this week & we took her out today to prove your theory correct! Its exactly as you suggested im kicking myself i never thought of this first weve been looking for all sorts of other problems. Just found instruction book for Micro Commander unit just got to work out how to increase the movement, tried adjusting on cable adjustment but its the server movement that needs increasing. Thanks again for your help your a star!"
 
"Hi Andre,

Glad to be able


"Hi Andre,

Glad to be able to help.
20 years of experience with Volvo engines gives you some advantage when it comes to problem solving. :)"
 
"Hi Martin. Followed instructi

"Hi Martin. Followed instructions & made adjustments & she went like a dream today. thanks again. Can you advise with another problem please.....im on my 3rd rev counter in 6 years. Its volvo penta (vdo technik) needle with digital hour meter. Its the same problem each time, turn on the ignition digital hours read ok, then start the engine and the display goes blank and the needle just "ticks" on the zero rev mark. Does anybody repair these or can i fix myself they are quite expensive to buy? Thanks Andre"
 
"Hi All
I have similar proble


"Hi All
I have similar problems, I have 3 KAD42's that were all replaced 2 years ago and have run 100 hours. Previous to changing the engines the boat ran at 40 knots without any effort and would overspeed if you let it, but since the change I can only make 34 knots (3400 rpm)on a good day and the two outboard engines run hot (95)if you don't pull back the throttles to 3200rpm. The bottom is clean, she has new filters and the water pipes are all good. I have not pulled off the turbo's as I find it a little strange two engines are acting the same, if no one has any other ideas I will do so this winter. I have also checked the throttles run to 100%, they are mechanical cables and they make the mechanical stop on the fuel pump. Given the weight of the boat 11 tons approx if the superchrgers cut out too early would the boat still have the power to get up too speed? or do the turbo's need the additional boost? I would appreciate any suggestions, many thanks"
 
"Hi Peter!
I see you are loca


"Hi Peter!
I see you are located in Stockholm, I am too!
But we take it in english anyway.
Did you earlier had KAD42 in your boat antd they was replaced with new KAD42´s?
I do not think you have a problem with your compressor or your turbos, the engines is too new.
If you only get 3400 RPM your engines works very hard, the RPM should reach 3900 when the whater is cold and at leas 3700 now with warmer whater.
Does all your 3 engines goes hot?, i do not think so, probably only 2 of them, as I think your problem is that your 3:rd engine does not help as it should, problably caused by not get full trottle.
I think you should investigate hard on your engine that not get hot, as I think this one is not giving any power to help the other 2."
 
"Hi Martin!
Thanks for the re


"Hi Martin!
Thanks for the response, I am located just outside Stockholm but I agree we keep it in english.
The old engines were kad 42's also and I suspected the middle engine as when they did the engine change they changed the middle drive and if they made a mistake with the ratio of the gears then it would explain it.
I have checked the temp of all the engines with a laser and they are pretty much the same although the middle instrument temp gauge reads low. I also checked the rpm with a strobe as the middle one over reads but it is a gauge problem and the engines all run at the same rpm.
One thing I did notice is the outboard engines have some sort of one way valve in the water intake pipes where as the middle is a straight pipe, I think this could be worth looking at with regard to the temp problem. As for the gear ratio on the middle drive then I will have this checked next time I lift the boat this winter."
 
"Hi Peter.
I think you have f


"Hi Peter.
I think you have found the problem an that is the middle engine with it´s drive.
Your engines works to hard, your outer engines have the correct drives and correct props for speed over 40 knots, but your middle engine have wrong ratio in the drive or wrong props, this makes all your 3 engiones to work to hard and you will not get your top speed and your correct rpm on your engines, and adding to this your fuel economy is probably wery bad!"
 
"Hej Martin

I am quite conv


"Hej Martin

I am quite convinced also, as for the fuel ecomomy I use about 4ltr's per nautical mile. I will get the boat lifted next week and I will let you know. If your every in the bockholmen area ask for me at the gas station and they will let you know where we are, we spend the summer on the boat.
thanks again!"
 
"Martin
Just to update you, w


"Martin
Just to update you, we have solved the problems with the heating and lack of power. It was due to incorrect adjustment of the fuel pumps. There are 3 adjustments,
1 low speed, this was ok
2 boost mid range, it allows a smooth change over from compressor to turbo,when we checked this there was a reduction in pressure when the compressor cut out and a delay before the turbo came in, even then it did not make it to full pressure.
3 High speed setting, these were also low thus the engines were not getting the fuel they need for the high speed range.
Now she runs well although we must make final adjustments to sync them and with a clean hull there will be no problem making 40 knots
thanks to you and everyone for your input."
 
"I have a kamd300 only reachin

"I have a kamd300 only reaching 2000 rpm smoke white at start up and idle, have tested most sensors, no code by the way on edc, change all fuel filtrers lift pump, found air leak at after cooler fixed it , compressor kicks fine but not poping out of the hole as fast, HELP!!! injectors maybe, or pump?"
 
"Hello everbody. I´ve a simila

"Hello everbody. I´ve a similar problem. This text is posted in "Low rpm and white smoke in Kad 42 230hp". First, I´m spanish, so... Sorry for my English, I will try give my all.

I want to buy a ship (8m) with a Kad 42 230hp (or Tamd 42) engine whith 800 hours. Theoretically it should reach 20 knots and 14 of cruise, but in the test only it reach 2500 rpm and 15 knots max, and pumping out white smoke. In addition, in a few minutes the engine (alone, doing nothing) lowered to a few revolutions and returned to 2500 in a few seconds.

Theoretically the seller says that it is alone for the dirty hull and that it has cinder in the turbo, but i don´t know if can be something worst.

I´ve readed the Martin Hellstrom solution in "KAD42 Problem with cutover between Super Charger & Turbo" but I don´t know if ca be relationated whit this.
SomeBody can help me? Thanks."
 
"bueno amigo ,yo tambien soy e

"bueno amigo ,yo tambien soy español y no se ingles pero para eso esta el taductor ,yo tengo un rodman de 8,14 metros con un KAD 42 ,y montado con cola DP-D y helices B6 a 3200 revoluciones de crucero hace 24 nudos y 3700 unos 29 nudos ,yo lo llevo siempre a 3000 rpm y hace 20 nudos ,la unica vez que no alcanzaba revoluciones suficientes fue una averia en la bomba inyectora
que se estropeo por el lodo del combustible ,ahora le ponga tres filtros antes de que llegue el combustible a la bomba y me va muy bien ,saludos"
 
"I have read all posts have a

"I have read all posts have a sport fisherman engine KAD 42A,B / DPX, engine completly rebuilt from top to bottom, brand new turbo, problem max rpm is 2200, cannot plane, have checked all electrical, lines, turbo and still have problems, any further suggestions also blows black on water badly"
 
Hi Stephen

Does the engine


Hi Stephen

Does the engine run hot? have you checked the timing and fuel flow. You can see the problems I had above and what I did to fix them.
 
"my 300 is cable to potentomet

"my 300 is cable to potentometor? norm is it jumps right out but now lack of rpm supercharger comes on and cuts at the right time but now rpm top 2600 was told injectors all bad they replaced, same prob. exaust pipes clean, trcked edc giving boost and no black smoke so think turbo ok.get code on needle lift sensor 7-2 ran it with unplugged ran fine for a year finally hooked it back up ran fine.Now codes even with new #1 injector unplugging did not work.seems to be lack of fuel.Ran it off remote tank no change so tanks ok Any ideas thanks, oh cleaned speed sensor,new filters clean bottom???"
 
Re: "Hi All I have similar proble

"Hi All
I have similar problems, I have 3 KAD42's that were all replaced 2 years ago and have run 100 hours. Previous to changing the engines the boat ran at 40 knots without any effort and would overspeed if you let it, but since the change I can only make 34 knots (3400 rpm)on a good day and the two outboard engines run hot (95)if you don't pull back the throttles to 3200rpm. The bottom is clean, she has new filters and the water pipes are all good. I have not pulled off the turbo's as I find it a little strange two engines are acting the same, if no one has any other ideas I will do so this winter. I have also checked the throttles run to 100%, they are mechanical cables and they make the mechanical stop on the fuel pump. Given the weight of the boat 11 tons approx if the superchrgers cut out too early would the boat still have the power to get up too speed? or do the turbo's need the additional boost? I would appreciate any suggestions, many thanks"

Having been thru all this I can tell you the first thing to do is connect a drum of diesel to the engine lift pump and take it for a run.When I did the engine performed like never before. I fitted a new inline fuel filter/ water trap and blew back thru the fuel lines. Have not had a problem since. Just one thing
30 litres last no time because the return fuel is going back to the main tank.
Jim
 
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