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KAD300 TurboSupercharger Problem

steve63

New member
Hi
First time poster hoping t


Hi
First time poster hoping that someone can offer advise. My 2003 KAD300 with EDC on 800 hours has just started to exhibit a problem. Supercharger kicks in at 1500 rpm as normal and kicks out at 2700 rpm. However turbo does not seem to kick so revs drop so supercharger kicks back in and this cycle keeps repeating. However once over approx. 2900rpm turbo seems to respond normally. No smoke.

Turbo pressure gauge has never worked properly so not sure of boost pressure.

I'm not sure its coincidence or a symptom of the underlying cause but I've also noticed that the engine will not rev out beyond 3600rpm in light trim whereas historically it revved to 3850rpm. Bottom is pretty clean.

Any advise or assitance would be greatly appreciated.

regards
Steve
 
"By way of update I had the Vo

"By way of update I had the Volvo Serviceman on the boat this week. He used a diagnostic computer to try and find a fault without success. We took the boat for a sea trial, reached 3750rpm so that seems to have been resolved. Turbo boost was 22psi (exactly the same as when we bought the boat 3 years ago)He checked the function of a flap on the airbox and it seemed OK. He also took off the turbo inlet pipe to check for carbon buidup on turbo vains but this was also OK. Overall he felt the engine was OK.

However I took it out for a fish yesterday and the primary symptom is still there ie unless the boat has good momentum up at the 2700rpm cutover between supercharger and turbo charger the turbo does not seem to kickin so revs drop so supercharger kicks back in and this cycle keeps repeating. However once over approx. 2900rpm turbo seems to respond normally.

I'm going to load the boat uptoday as I htink its going to be much worsein heavy trim.

Any suggestions would be greatly appreciated.


PS Dean thanks for your call and advise on the phone. Much appreciated"
 
"Hi
I too have the same prob


"Hi
I too have the same problem with my starboard Kad 300. If rpm drops under 3200 i get very bad hunting which means i have to stay 3300 and above for this to stop which is 27,28kts and can be a bit fast in a heavy sea.Any suggestions would be appreciated thanks Gary Walker"
 
Re: "By way of update I had the Vo

"By way of update I had the Volvo Serviceman on the boat this week. He used a diagnostic computer to try and find a fault without success. We took the boat for a sea trial, reached 3750rpm so that seems to have been resolved. Turbo boost was 22psi (exactly the same as when we bought the boat 3 years ago)He checked the function of a flap on the airbox and it seemed OK. He also took off the turbo inlet pipe to check for carbon buidup on turbo vains but this was also OK. Overall he felt the engine was OK.

However I took it out for a fish yesterday and the primary symptom is still there ie unless the boat has good momentum up at the 2700rpm cutover between supercharger and turbo charger the turbo does not seem to kickin so revs drop so supercharger kicks back in and this cycle keeps repeating. However once over approx. 2900rpm turbo seems to respond normally.

I'm going to load the boat uptoday as I htink its going to be much worsein heavy trim.

Any suggestions would be greatly appreciated.


PS Dean thanks for your call and advise on the phone. Much appreciated"
What was the problem?
 
Hi
Did you ever find the solution to this problem? I have exactly the same problem on a KAD 43P - supercharger kicks in at 1500 rpm and out at 2700 rpm but engine revs immediately drop until supercharger kicks in again. Volvo have fitted a new turbocharger but still no improvement. Details of how you solved your problem would be gratly appreciated.
 
Hi Aquila

Just a quick one, i see you have had the same fault, you say the turbo has been changed, was this with a new unit?, also have you had any water in the fuel over the last few years?, we have had a few kads where the injection pump has needed to be overhauled due to water contamination to the system over years and this then causes wear internally
 
Hi The Turbo was rebuilt by a spe******t KKK rebuilder. However nothing was found when it was stripped down but it was still completely rebuilt. There has been no water contamination of the fuel. The supercharger is set to cut out at 2500rpm and I wonder whether this is too low - other respondents talk about 2750rpm.
Regards Aquila
 
This issue is quite common on the Volvo Super/turbo charged engines. We have had it on our KAD32's as well. Twice it has been due to wear in the turbos (they are pretty crappy quality like many of Volvo's modern parts), and once due to an air leak caused by loose bolts on the inlet manifold.
Ideally you need to get a boost gauge on the engine and see how low the turbo boost is when the supercharger cuts out. Things I would check:
1) Listen for any strange 'whilstling' sounds as you rev the engine. These can be signs of an air leak in the manifold or the rubber connecting pipes.
2) Check all the turbo to manifold pipes and connectors.
3) Check the air filter (not sure if a blocked air filter could slow the turbo, but I guess it might
4) Check that the supercharger is cutting out at the correct rpm's
5) If all that looks OK, you need to check the boost as the next job is to replace the ridiculously expensive turbo
 
This issue is quite common on the Volvo Super/turbo charged engines. We have had it on our KAD32's as well. Twice it has been due to wear in the turbos (they are pretty crappy quality like many of Volvo's modern parts), and once due to an air leak caused by loose bolts on the inlet manifold.
Ideally you need to get a boost gauge on the engine and see how low the turbo boost is when the supercharger cuts out. Things I would check:
1) Listen for any strange 'whilstling' sounds as you rev the engine. These can be signs of an air leak in the manifold or the rubber connecting pipes.
2) Check all the turbo to manifold pipes and connectors.
3) Check the air filter (not sure if a blocked air filter could slow the turbo, but I guess it might
4) Check that the supercharger is cutting out at the correct rpm's
5) If all that looks OK, you need to check the boost as the next job is to replace the ridiculously expensive turbo



I response the above, I am having similar issues in that the clutch on supercharge keeps burning out.

I feel that the Air supply is not clean/cool enough. have rerouted the air intake around the engine to a cooler area and have installed inline blowers to feed clean dry air to that area.

still to test run the boat!

any thghts on this?

Can the super charger be fittd with a switch to control when it kicks in??
 
Many people put a switch in the wires feeding the supercharger clutch to allow the supercharger to be turned off and on manually. Is your clutch burning out or is it the electronic control circuit that is burning out? It is unusual for the actual clutch to burn out, whilst the control circuit failing is more common and can be fixed with an aftermarket change to the circuitry.
 
Many people put a switch in the wires feeding the supercharger clutch to allow the supercharger to be turned off and on manually. Is your clutch burning out or is it the electronic control circuit that is burning out? It is unusual for the actual clutch to burn out, whilst the control circuit failing is more common and can be fixed with an aftermarket change to the circuitry.

How do you rebuild circuitry for clutch. I'm burning my clutch every 4-5 fishing trips. I have a kad32 and I'm changing clutch every few trips. Problem is the fuse on black box trips and when reset continues to trip. Change clutch and doesn't trip for 4-5 trips then acts up again. Thanks
 
Is it the clutch on the front of the supercharger or the electronic control box on top of the engine that is failing? If you run those engines for long periods on the supercharger (say on rough weather days where you need to go a bit slower etc) then the control box is known to fail quite regularly. The fix for this is to put a switch at the helm that breaks the wiring to the clutch magnets. You can then turn off the supercharger when you want to run at medium speeds.
If the clutch itself is burning out then you may have a problem with the supercharger. They can get 'glued' up with fuel/exhaust type residue and become very difficult to turn. We had one that was completely seized and were told by Volvo that they are an 'unserviceable item. They tried to sell us a new one. We pulled it apart and gave it a full service before we realised that the problem was just sticky residue on the vanes. We still had it off the engine so we just ran carb cleaner etc through the vanes and cleaned them up. That was around 1000 hours ago and it is still as good as new.
 
Is it the clutch on the front of the supercharger or the electronic control box on top of the engine that is failing? If you run those engines for long periods on the supercharger (say on rough weather days where you need to go a bit slower etc) then the control box is known to fail quite regularly. The fix for this is to put a switch at the helm that breaks the wiring to the clutch magnets. You can then turn off the supercharger when you want to run at medium speeds.
If the clutch itself is burning out then you may have a problem with the supercharger. They can get 'glued' up with fuel/exhaust type residue and become very difficult to turn. We had one that was completely seized and were told by Volvo that they are an 'unserviceable item. They tried to sell us a new one. We pulled it apart and gave it a full service before we realised that the problem was just sticky residue on the vanes. We still had it off the engine so we just ran carb cleaner etc through the vanes and cleaned them up. That was around 1000 hours ago and it is still as good as new.

The clutch has to be changed every 4-6 trips. On 5or6 trip the circuit breaker trips on small black box as soon as supercharger comes on. Reset it and trips again within 2 minutes. Drained oil from super charger and oil is gray in color and looks like metallic paint flakes in oil. Doesn't look orange and clear like the original. Little over 120 hours on oil.
.
 
You may have done a bearing in the supercharger. The oil normally stays good for 100's of hours. Pulling it down for a service is a DIY job is you are moderately capable. Just take lots of pictures and notes, and be especially careful to mark the gears etc for the supercharger vanes. They need to go back in exactly as they came out or the vanes will bind through incorrect 'timing'.
 
Try swapping the boost sensors from one engine to the other. I watched a tech have an injection pump, injectors, and turbo rebuilt over the same symptoms you describe. Fixed nothing. I sea trailed the boat a few days later and swapped the boost sensors and the problem went to the other engine. Diagnosis was obvious.
 
Try swapping the boost sensors from one engine to the other. I watched a tech have an injection pump, injectors, and turbo rebuilt over the same symptoms you describe. Fixed nothing. I sea trailed the boat a few days later and swapped the boost sensors and the problem went to the other engine. Diagnosis was obvious.

Where is boost sensor located?
 
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