KAD 300 engine temps

Al Dickson

Al Dickson

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Can someone tell me what the normal operating temps are for KAD 300's please.

Under normal running up to about 3500 rpm my Starboard engine runs approx 200 degrees and the Port one (which also heats the hot water) runs about 185 degrees.

At the weekend I decided to open her up a bit and after 10 mins at WOT (I presume this is actually manufacturers max 3800rpm and not the 4000rpm the tachos read) the Starboard engine was reading 250 and the Port one 200 - cut back the revs to 3500 and the temps quickly dropped back again.

250 Just seemed a bit hot to me ...
 
Have you checked filters? Not sure about up North but its been a very bad year for weed on the South Coast especially at the top end of the river Hamble.

We had to limp from Calshot to Cowes on one engine because of this

SAM_1137.jpg
 
Yuk - normally we get very little of that in the Clyde so I only check them every 6 hours or so and apart from a couple of bits of sea shell they are OK. I'll check tomorrow
 
185F seems normal for cruising speeds and They should not go over 90C or slightly under 200F at WOT. 250F is too hot.
 
Which engine had the impeller problems earlier this year

You would expect the engine with the colorifier to run cooler initially but should even out on a run.
Which engine run power steering?
 
Questor said:
I suspect the guage isn't reading true, as I thought the alarms were set to trigger at approx 92°C (which is less then 250°f)
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95°c +/- 3°c on the 300 so that is 198 to 208°F so the alarm should have gone off. Perhaps worth swapping the sensors over to see if it is a faulty sensor?
 
Eastbrae said:
Engines have done 840 hours and serviced by Volvo every season (last done at 800 hours) How often do the HE's need cleaned out ?

Alan
Click to expand...

I think the handbook recommendation might be 5 years but I am really not sure - VolvoPaul's your man for a definitive answer. A few years ago when I had a Targa 37 it would overheat at WOT, and this was sorted out by cleaning out the heat exchangers. At that time the boat had done c.700 hours, and was about 8 or 9 years old, and the heat exchangers had not been previously done.

Cheers
Jimmy
 
I always work in deg C anything over 92 deg C and the system in my opinion isnt working a good as the day it left the factory, even 2 tubes in a het exchanger stack will reduce the cooling capacity, on the 41/42/43/44/300 series coolers they build up on the end plate, its a simple enough job to remove and check just 2 hoses and 1 bolt and its off, of course boat type and installation permitting, also oil coolers build up reducing the flow of sea water through the whole system, kad 300 is slightly different route as raw water hits the intercooler first then heat exchanger and oil cooler last, so thats where you will get a build up of sea weed and growth on a 300.
 
I was also thinking the alarm should have sounded, there is a test switch to check that the alarm buzzer works. Perhaps try that before you switch the sensors.
As always with these issues a ir temp thingy is very helpful.
 
My best cruising rpm is 3000 and 3500 for fast cruise.
Both at 3000,3500 and wot temp stays at 85C/185F.
Last month I did a long trip at 3500rpm and temp never increased and stayed at 85C.
This year I did cleaned heat exchanger, oil cooler and steering oil cooler. Engine oil cooler was a bit dirty but untill cleaning it didn't caused any fault.
I have a few friends with single and twin KAD300s and they have/had overheating and/or higher temps while cruising without alarms triggered. When they cleaned/flushed heat exchangers and coolers their temps stayed at 85C.
Best regards.
Melida
 
Thanks people this is all good stuff - im not suspicious of the impeller issue at the start of the season - they were only run for a few minutes off load and if Volvo are to be believed itt was acutally an airlock :-) we have done 50 hours since then and the temps at normal RPM are all same as last year.

There have been no alarms and the buzzers are working

I will check which engine the PAS pump runs off

I did wonder about the accuracy of all the guages (apart from the fuel guage which is the first one I have ever had thats bang on !) the max rpm for the 300 is I believe 3800 rpm but the tachos read much higher than that at WOT.

It looks an easy job to take the heat exchangers off and from what Jimmy & Paul say its probably overdue as the boat is in its 8th season - i'll check with the previous owner to see if he ever cleaned them - is it a DIY job to actually clean them ?
 
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Hi there,
I have KAD 300`s ,850 hrs apiece ,on a V42
Last year I had an overheating problem on port engine.
Normal running temp 180(2000rpm)-200(at 3500rpm).
mine was hitting 240 on port at 3200rpm(alarm going off though).
On investigation I had taken seaweed into the exhaust inlets but they blocked before the raw water strainers, so they appeared clear.
I couldnt clear this blockage , so throttled back to 3000rpm and ran her at this rpm, until her lift out at the end of the season. I cleared the blockage easily and she has run perfectly this season.
S
 
Well thats us all sorted - checked out all the filters, heat exchanger etc etc and took her for a run out with the engineer who pointed his heaat detection gun thing at each engine.

Both are running within 3 degrees of each other and at approx 87 degrees C which is why the alarms never went off - the guages read 115 !!

Thanks for all the advice

Alan
 
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