New to a Nissan LD28M

[TorreyWP]

I am new to a 1985 FC with the Nissan LD28 engine. Since acquiring her in October I have run up close to 30 hours to a total of 2116, she has ran great aside form some silly stuff; raw water hose bursting under way and an alternator belt breaking. I am the junior mechanic at a local marina and I have a particular interest in learning as much as I can about this boat mechanically and keeping her running reliably.

After having a few things happen under way, I got a baseline by preforming lots of preventative maintenance. All new hoses, belts, oil, filters, trans fluid, coolant, valve lash, raw pump impeller etc.

The boat has been run in salt water for the majority of its life but has faired well, nothing has come apart with abnormal difficulty so far.

I have two concerns I am looking for input on: Exhaust elbow issues and injection pump belt

Having reading some of the precautionary tales here about Nissan exhaust elbow issues, I removed mine for inspection. It does not appear to be in horrible shape. I was thinking I would have a local machine shop boil it, clean it up and possibly magna flux it to get an idea of where its at. I would just blindly replace it but the custom made options seem steep. Its stamped with "Barr Marine 20-0082". Might be worth seeing if they are still available as I am familiar with Barr still being around making Mercruiser replacements. Thoughts?

The injector pump belt. I have a pretty well detailed repair and maintenance log for the boat going back to 2004. The engine has not been through any very major work. It is my understanding that this engines injector pump is belt timed and a belt breakage = dead in the water. Anyone have experience replacing one?

I have a service manual for the LD28 that I eventually need to share with the library and the marine application supplements. I would love to hear any thoughts about those concerns and any other problem areas I should be aware of.

[TorreyWP]

Update:

A simple google search revealed that the Barr Marine 20-0082 riser elbow is still available, and cheap! Like under 150. Maybe this will help someone with the same issues. This is still a cast iron elbow so those in salt may still benefit from a custom with different metals.

[kerrye]

Maybe coat the inside of the cast iron with epoxy? I've fixed a lot of cast iron sewer pipes with epoxy and it holds up well.

[tego]

Howdy Torrey and welcome. I'm considering doing the IP belt myself in the near future. The manual says every 500 hrs, and I'm knocking on that door now. It appears that it's going to be a bear. I have to remove my heat exchanger, and that'll get me about 5-6" space in front of the engine and some visibility, but I'll still be using a mirror to see the timing marks. I also have a small oil leak under the front somewhere (can't see exactly where). Maybe I'll just remove it and it'll be a whole lot easier! There's a lot of LD28M info on the Nissan Diesel site but you have to dig all over for it. I'll post my experiences with this when I tackle it. Luckily, I can work on mine all year long down here in TN, so probably after the first of the new year. - Ben

[JT48348]

That's good info on the exhaust elbow. Would you be able to post some pictures of your set up?

[TorreyWP]

Pictures soon!

Ben, Thanks for your response...agreed: the task is a bit intimidating but I do believe the marine application will be easier compared to our automotive friends (no radiator, ac, power steering etc removal required..). Also I agree, the Nissan Diesel site is a bit cryptic...this has been my best guidance so far:

http://nissandiesel.dyndns.org/viewtopi ... nce_IPBelt

There you will find the info you need to replace your front crankshaft seal that is most likely the cause of your slight leak. I plan to do mine as well while Im there. I wish there was more info on how to come across a tensioner. I hate to put old (possibly suspect) parts back when replacing other related parts with new. As far as I can tell the tensioner is NLA and if it fails even a new belt can skip a belt tooth causing issues. Anyway, I'll be on the look out for your posts if you start busting knuckles before me. I plan to send my exchanger out for descaling while its off.

Im jealous, I'll play with mine all year too but ill be under the shrink wrap and Buffalo cold!

Torrey

[TorreyWP]

Some engine and exhaust pictures attached. I'll post more of the inner condition of the elbow and scan the service manual and marine supplements I have to add to the library this weekend.

Torrey

[JT48348]

Interesting. My engine has the same fiberglass repair. Thanks for the photos

[TorreyWP]

Its a common place for the muffler to fail when the muffler does not get drained down during winterization. The water inside freezes, expands and blows the top out. Patched properly they can last a long time. The muffler is available from a company called Centek if you are ever interested in replacing.

Here is the link to their site. You would just need to get some dimensions to determine the direct model replacement.

http://www.centekindustries.com/vernaliftfig2.html

[Beta Don]

I wish there was more info on how to come across a tensioner. I hate to put old (possibly suspect) parts back when replacing other related parts with new. As far as I can tell the tensioner is NLA and if it fails even a new belt can skip a belt tooth causing issues.

www.rockauto.com is a good source for LD28 parts. They have most of the engine parts available and at pretty good prices. The IP belt is $7.69 and they have the bearing for the tensioner available for $7.01. Click 'Nissan' and '1982' and 'Maxima' and then '2.8 L6 diesel'. The IP belt is under 'Engine' and it's called the 'timing belt'. The tensioner bearing is listed right under it

Don