Nissan LD28 Heat Exchanger HELP!

[JFOkie]

Hello,

I've removed the heat exchanger on my Nissan LD28 and had it cleaned. However, I need to find new gaskets and a pair of end caps as the original need to be replaced.

Does anyone know where I can find the gaskets and end caps? I love this engine, but trying to find parts is a problem.

Worst case, I guess I could install a new heat exchanger, but how do you know what size to get? What type or model will work?

Thanks,
John

[rebuckley]

John,
Not sure what exchanger you have, I have found most of my exchanger materials at "Mr. Cool" give a quick google for him with the word exchanger his place is in NJ, but I have called him to get clarity on my orders and needs, always helpful!

http://www.mrcool.us/

[TorreyWP]

The end cap gaskets can be made with rubber gasket material from NAPA or similar outfit. If you have the old ones and they are in one piece you can use them as a template, otherwise use the cap to trace onto the gasket material and cut with a sharp utility knife. As for the end caps, I have an old tank and will look closely at the end caps, I'm not sure what kind of shape they are in...

As for a replacement heat exchanger, its possible. A specification to note is that it is an expansion style tank (has the radiator cap on the exchanger itself). Generic and other engine manufacturer tanks exist and somewhere I saw a formula for capability of heat transfer. Outlet and inlet hose sizes would be important. I started to head down this road myself recently for a spare LD28 engine I am preparing to get running. Obviously with a generic tank some hoses would have to be replaced and the tank would ultimately end up getting mounted to the bulkhead wall infant of the engine.

Try:

http://www.orcamarine.com

I'll post any more info I gather in regards to a generic fit that has proper capability.

[JFOkie]

Reb & Torrey,

Purchased some gasket material and made new gaskets; also flushed and cleaned the heat exchanger. I installed the exchanger, but ran out of time for a trial run. It fired up with no leaks, will take it our for a trial run Friday and see what happens.

Thank you for you input, very much appreciated.

Regards,
John

[JFOkie]

Reb & Torrey,

Well, I have now pulled the water pump and will order a new one; this is the only thing left for me to try.

I wasn't seeing any water coming out of the exhaust, so I took off a hose and saw that the impeller was turning. My guess is that it's not a good seal or something...…

Needless to say, it has been a terrible summer for boating for me.

Regards,
John

[tego]

John, If the impeller was turning in the raw water pump, it'll pump water even if it is worn. Before you get a new pump, try pulling the hose off your engine raw water thru hull (after turning it off of course) and you should have a small geyser when you open it. If you don't, the thru hull is blocked. This is quite common and the first check if your exhaust is dry. I assume you've pulled all your hoses to make sure your raw water lines ahead of the pump don't have a hole or air leak. Your pump will not pull water thru a hose that has an air hole somewhere. Another possibility, disconnect your water hose from your exhaust riser and then blow thru your H/E exit hose to make sure it's clear.. This last test will also check water flow thru your water heater and your tranny oil cooler. This tranny oil cooler is often plugged with old impeller chunks that a PO never checked for. Lastly, you may have the old original cast exhaust riser and it may be severely corroded, blocking water flow into the exhaust tube. Good luck! This is a very simple and reliable engine and I love mine, but a less-than-informed PO can really make it tough on a new owner for awhile. Ben

[rebuckley]

Agree with Ben. Start at your through hull and make sure water is moving, check hoses for leaks or cracks, gasket on impeller housing, any in line exchanger or cooler becomes a trap,for impeller parts. but tracing e flow through the system will help you locate the place you have an issue and make it much easier to troubleshoot

[JFOkie]

Time for an update. I pulled the water pump and found a few things; the o-ring was pretty old and probably not creating a good seal and the fly wheel (or whatever it's called) was wobbling and the shaft didn't seem to be spinning properly.

Ordered a new pump from Jamestown Distributers and received it the next day (today) and will install it Friday.

I've checked the raw water intake and even went it and cleaned it just in case. I've also pulled every hose and checked for blockage; everything seemed to be okay.

This is the fist issue that I've had with the engine and even though it has been frustrating, I love the Nissan LD28. Will provide another update this weekend, hopefully everything will go smoothly and I will be able to get some use out of the boat.

Thank you everyone for your suggestions and assistance, very much appreciated.

Regards,
John

M/V Nirvana