Perkins Prima m50 cooling system maint

[mjcayman]

Recently took apart the heat exchanger, drained the coolant (flow arced over my contraption to catch and ended up pretty much everywhere), and am replacing the thermostat and sender. All this started with a temp gauge that read too cool... Lasered the thermostat housing and it read right so engine is fine. Anyways few questions: Does the HX stack go back either way? I didn't think to look when I took it out. Are there no gaskets for the Prima 50- I only see the rubber end caps and the two hose clamps on each end. Lastly- how do you bleed the air from the system after refilling (and offhand anyone know how much coolant it needs?)? Sorry I am not a mechanic and am just trying to learn some routine maintenance. FYI the whole system looked clean after 20 years. The HX tube was perfect.

Last thing- what do I keep reading about sleeves? My stack came right out by itself. I kinda see two rubber sleeves inside the HX, should they have come out? Can I just slide it right back in and does it matter where the holes in the tube are/ or direction they face?
Again, apologies, I am no diesel mechanic by any stretch! And have searched google for hours.

[mjcayman]

Anyone?

[oldcal46skipper]

Hi,
I am a trained, experienced marine diesel technician with over 50 years experience. Yes, I am old and opinionated. In my shop we only work on Perkins as they are built to last. We have a Perkins Prima M-80 that we have prepared to sell, but M-50 should be about the same.
My comments embedded, marked by ***

Hope this helps,
Tom

Originally Posted by mjcayman

Recently took apart the heat exchanger, drained the coolant (flow arced over my contraption to catch and ended up pretty much everywhere), and am replacing the thermostat and sender. All this started with a temp gauge that read too cool... Lasered the thermostat housing and it read right so engine is fine. Anyways few questions: Does the HX stack go back either way?
***Should go either way if both ends the same. I flush and soak in vinegar overnight.

I didn't think to look when I took it out. Are there no gaskets for the Prima 50- I only see the rubber end caps and the two hose clamps on each end.
***The rubber end caps act as gaskets. Clean them and apply a little non-hardeneing gasket sealer, assure your hose clamps are in good condition

Lastly- how do you bleed the air from the system after refilling (and offhand anyone know how much coolant it needs?)
***Unless your coolant heated water heater is higher than your fill, it is self bleeding. If any part of the system is above the fill, then will need to bleed at the highest point.

? Sorry I am not a mechanic and am just trying to learn some routine maintenance. FYI the whole system looked clean after 20 years. The HX tube was perfect.

Last thing- what do I keep reading about sleeves? My stack came right out by itself. I kinda see two rubber sleeves inside the HX, should they have come out? Can I just slide it right back in and does it matter where the holes in the tube are/ or direction they face?
Again, apologies, I am no diesel mechanic by any stretch! And have searched google for hours.

[jimbunyard]

Don't know about the sleeves you're referring to, but the exchanger goes back with the tiny hole up and the 2 large holes down.

[Jaden44]

Expect that you've already found answers to your enquiry. If not, then suggest that you use the CF Search facility and look for the thread Perkins Prima-50 HeatExchanger started June,2012. Read the full thread and the replies. Your questions are answered there.

In your question, you say that you saw two(2) rubber sleeve pieces (inside the heat exchanger bundle housing) after removing the tube stack. This seems odd! To my knowledge, there is only one (1) sleeve piece on the heat exchanger tube bundle. The sleeve material could be either rubber or plastic (dependent on engine number/date of factory assembly). If you see two rubber pieces, then its possible that the single rubber sleeve has at some time in its life, divided into two halves. Either way, inspection is suggested to determine the origin of the pieces.

Suggest that you install a replacement sleeve. See below.

The sleeve performs an important role. A baffle wall is cast to the inside of the heat exchanger cavity. The baffle is factory drilled oversize to enable the tube bundle to slide the full length of the HX cavity. To install the sleeve, It is necessary for the sleeve to be first installed on the end of the tube bundle, and then slid forward (attached to the stack). Thereafter the sleeve will engage with the baffle and also retain a friction fit on the tube stack. At this point, two sealed chambers are created inside the exchanger cavity. A serviceable sleeve is necessary to ensue that the heat exchanger functions correctly in that the raw water flow is directed from the first inlet chamber, through the tube stack (only). The raw water flow then exits the tube stack in the second chamber. Expect a new genuine replacement sleeve to be costly (+/- US$50). Regards.