1985 Perkins T6-354 RPM

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Fogarty62

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Joined
Oct 18, 2018
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7
Location
USA
What is the average rpm on this. I have a 35’ Overseas Trawler.
If I run over 1500 she starts to overheat. Strainer is clear as well through hull screen.
 
There are several possibilities to your problem.

1, Remove the end cover off your Jabsco seawater cooling pump, check the vanes are all intact, if some are broken, drain down any water then get a wet & dry vacuum cleaner, place the nozzle UP the pipe towards the heat exchanger to suck out any broken impeller vanes or debris, then, replace the new impeller using washing up liquid as a lubricant (it also lubricates the impellers during the first dry start up). Run the engine and check for leaks.

2nd, using a proprietary radiator flushing liquid clean the cooling system as per directions, if necessary do it twice, when refilling after cleaning the cooling system fill with an anti-freeze mixture.
Even in hot climates, the AF mixture contains both a lubricant for your recirculating water pump and a cleaner to keep your water galleries clean to aid dissipation of heat via radiation and I highly recommend keeping it in all year round.

3rd, are you over propped ?

I hope this helps you solve your problems BUT, fix the problem and under NO circumstances let the engine overheat
 
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Thanks, check it how? What am I looking for?
You probably have the Mannycooler like I do. (1984)
That could be a problem. The ends were made from dissimilar metals and corroded and the tubes may need replaced.

There is a company in Oregon that rebuilds them, but it is not cheap.
Orca Marine


The other option is a $4500 replacement kit from TAD (Trans Atlantic Diesel).
 
Actually there should be two thermostats in the front of the cooler you can check. I would pull them and check the tubes and then run it without the thermostats and see if the temp holds.
 
This is scary because I just bought an engine like this and did not presssurize the system to see if it leaked or if it over heated. Just ran it off the coolant in the heat exchanger. I hope I didn’t screw up. Having the raw water pump rebuilt now and I guess we will find out soon enough.
 
You should be able to cruise at 2200 - 2500 depending on the model.
Lots of replacement heat exchangers on the web for about $1200 or less.
Good place to look: Perkins Marine Heat Exchangers
 
What is the average rpm on this. I have a 35’ Overseas Trawler.

I also have the T6.354
In regards to rpm, I usually run around 1800 to 1850 rpm at about 7.5 to 8kts. Temps at this rpm are usually around 175 degrees.
 
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Pull the hose (both ends) from the outflow side of the raw water pump and take a look. God knows how many bits of old impeller vanes are in there.
 
If you need a heat exchanger the OE suppliers are www.ejbowman.co.uk.
Drop them an email with your engine number and they can supply and ship the correct parts to suit your engine, probably cheaper than buying local and you have an OE part.
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