MANN ENGINE INJECTORS

[jas0381]

I was wondering if anyone on this site has run the injectors past the 1000 hour mark that Mann suggests for replacement. I am close to that number. Have limited smoke at start up and have Good fuel economy. Knowing how Mann is very conservative about their recommendations I am wondering if this is also a very conservative number. Your thoughts please. Thanks.

[stanfromhell]

Injectors on any diesel engine will work very well for long past 1000 hours as long as the fuel being supplied to them is free of contamination and WATER. The care you take monitoring your fuel filters and water separators will determine the life of your injectors. Heavy smoking and hard starting are the most common symptom of worn injectors.
If you are unsure of your injectors it is very easy to remove them, take them to an injector rebuild shop for testing. Many places will do it at no cost and will show you the spray pattern of faulty injectors you might have. Also, there is no need to purchase new injectors, have them rebuild instead, they will work just as well and last just as long as new ones.

[Omega]

Hey Joe,

I replaced my injectors a couple mounths ago, trying to mitigate a severe sooting issue when I was under way. Unfortunately, I don’t believe the injectors were the entire issue, as I found the previous owner re-propped the boat with a set that was 2 inches overpitched and caused undue bogging of the engines. I say that, as I had similar sooting after it replaced the injectors, The issue went away the second I de-pitched the props and has been fine ever since.

What i I learned in the whole of my issue is that the injectors do have a longer life than 1000 hours. I have about 1700 on my engines and only worried about my injectors when the sooting got really pretty bad. A little smoke at start up is normal, depending on the temp etc. I personally wouldn’t mess with the injectors if things are still running well, etc. If I was concerned about anything, I would probably start with having them tested and replace or rebuild only the ones that don’t meet the oem requirements. At about $900 per injector new, there’s no need to replace what doesn’t need fixing It would save you a ton.

Oh and btw... the correct nozzles and such for rebuilding your existing injectors generally have to come from Bosch in Europe.

I hope this helps,

BJ
OMEGA
5788

[MerlinV]

We’re at 1150 hours now on our MAN’s, and we are planning an injector service this winter. There’s no sooting on the transom, but we are seeing some extra smoke at startup.
The plan is to service the existing injectors at Fred Holmes Fuel Injection in Richmond BC. I may also have the turbos serviced there at the same time.

[simbad]

Isn’t that extra smoke at start up kind of normal in the cold weather? I have it too not a lot but enough to notice but it’s gone as it warms up. Just wondering if you really need to do injectors so regularly. Per BJ above seems like he was more props than injectors.
I’m due a service and wondering what I need to put on my list.

[jas0381]

Thanks all. Very much appreciated responses.

[Omega]

It’s not too much to have th injectors pulled and tested. It’s woth it, as rebuilding all twelve injectors can cost several thousand dollars, where rebuilding a few can save a lot...

BJ