Winter Service, Injector re-build re-tip, coolant filter add

[rustybucket]

Heading down to the boat with the 15yr old driving, needed a distraction so figured I'd update this.

On the list for this winter was a full tune up. Before we got ready for the tuneup procedure I ran a few tests on the engines, and really glad I did.

These are 600hp 8v92 TI's

The only real 'symptom' we had was port side of port engine egt was running consistently 50degrees F higher than all the other 3 egt sensors. Also, even after prop adjustment we were about 150 rpm off of our desired WOT loaded rpm of 2350. Also, coolant temps seemed to creep up slowly when running over 2100 rpms, which leads to the thought of being overloaded/overpropped or a mechanical issue being present.

Both engines are about 300hrs off major overhaul. They start right up, little/no smoke and generally purr like kittens.

Test #1 was to run the boat at 1500 rpm at the dock and take temps of all exhaust manifolds approx 1" from the heads. (as a disclaimer I do not know if this is an actual Detroit Diesel test, I just thought it would be a good way to isolate a possible issue by showing me the cylinders that may, or may not, be 'out').

Here are the results from that test.
Port
Fore to aft
1500 rpm
outboard
156 - 157 - 187 - 213
Inboard
188 - 167 - 195 - 120


Stbd
Fore to aft
1500 rpm
outboard
205 - 193 - 235 - 197
Inboard
194 - 164 - 169 - 188


There were more anomalies than I was expecting to find but the two that really stood out are the 120 deg on port and the 235 on starboard. The other variances were deemed 'reasonable' by a couple of old timers with detroit experience.

After that test had isolated a couple of cylinders of interest I performed a dead cylinder test on the 120 deg port cylinder. When I pushed down and held the injector plunger down there was very little, if any, change in engine rpm. When I pushed down any other injector plunger on that engine there was a notable stumble which quickly recovered due to the governor compensating.

So basically we were running on 7 cylinders (at low rpm at least) on port engine.

At this point I decided that I would be pulling all 16 injectors and sending out for rebuild.

I ran a bore scope up in the 120deg cylinder and can still see very fresh cross hatch hones, everything looks good. I'll be performing a cold compression test on it this week as well to rule out a bad valve.

The injectors in my boat are 7125's which have 7 spray holes in the tip. The current injector for this engine is the 5670, which has a 9 hole spray tip.

After some consultation on Boat Diesel I decided to also at this time have all the 7125 injectors updated to 5670's. The 7125 and the 5670 are identical in every aspect except the tips with the 5670 having 9 holes which is apparently for better low idle fuel atomization. Being that we spend extended times at trolling speed I figured it would be an appropriate upgrade/update.

So all 16 injectors were pulled Friday night. It took approx 4hrs of labor (from me) and wasn't a bad project at all. I did end up with a couple of skinned knuckles and probably should have worn mechanics gloves during the procedure lol.

The injectors shipped out this morning to RPM diesel in Ft Lauderdale for rebuild. If all other parts are good the bill should be $95/injector to rebuild our injectors.

Other items on the list this winter are a couple of small oil leaks/slobbers, mainly on cover plates that will be addressed.

Also we will be adding coolant filters on both mains and the generator. I ordered 3 filter heads today. No particular reason or symptom to make me add the coolant filters other than I run them on every other diesel engine I own and have been routinely amazed at what they pull out at filter change. Being that the 92's are wet liner I feel that coolant condition and cleanliness would be very important to longevity.

https://www.dieselequipmentinc.com/...MI9O-qysaF5gIVBZyzCh1AhwVgEAQYAiABEgK5lvD_BwE


I'll update the thread as these projects progress.
These use the same napa filters I use on my trucks/tractors, so it will be nice to have a filter common to all.

 

[Cricket]

Rusty, think I remember you posted about an additional oil filter you had added or are about to.
What is the brand because it probably is a project we would like to do. Looked online and Amsoil was all over the place.
We are already moving the stbd engine fuel filter because you have to spin it off to change the raw water impeller, only took me 17 years to finally do it.

 

[oscarvan]

https://www.dieselequipmentinc.com/p...iABEgK5lvD_BwE


I see a bracket..... Am I supposed to see a head? Thanks.

 

[ageless]

Rusty, don't just replace the tips of the injectors, it's another $100 per but do the barrels and plungers as well. I have had them do a couple (m15) at a time as they become weak. Maybe mine costs more but they were $175/ea You should be good to go for several years unlike reliajunk's

 

[kelpy]

RPM won't return an injector to you if it isn't in perfect condition.

 

[rustybucket]

Rusty, think I remember you posted about an additional oil filter you had added or are about to.
What is the brand because it probably is a project we would like to do. Looked online and Amsoil was all over the place.
We are already moving the stbd engine fuel filter because you have to spin it off to change the raw water impeller, only took me 17 years to finally do it.

I went with the Frantz triple stacker. I looked at the Amsoil and others and honestly they are all probably good enough. If I had cats or newer tech engines I'd probably go with the amsoil or one of the other newer tech bypass filters. It seemed like the Frantz triple stacker had a greater capacity for soot than the others I looked at. After all, the Frantz filters are the same era as my Detroits so they were basically made for these engines. The triple stackers were VERY common with long haul truckers with detroits. They are no longer produced so you have to find them used or new-old stock. I was able to find two new-old stock on ebay for a couple hundred dollars each. One of them is weeping oil on the t-handle so I'm going to replace all the seals in them with vitton this winter as well.

This is not my image but shows a triple stacker next to a normal single stack bypass oil filter.

The idea is the same as the coolant filter, it takes a small stream of oil (I tapped into one of the out plugs on the full flow oil filter), runs it through the triple stacker cellulose or synthetic filter media which filters it down to < 2 micron, removing all soot particles that the full flow filters completely miss, then I returned the oil to one of the plugs just above the oil pan. I believe these plug were intended for alternate dipstick locations.

The cellulose media removes any moisture/water from the oil, the synthetic media will not remove moisture but has different properties, they slip my mind at the moment, but I think I'm going to be running 2 cellulose and 1 synthetic in each triple stack to get the best of both worlds. Currently I have 3 cellulose media in each can b/c that's what the filters came with.

Some guys even stick a strong rare earth magnet to the side of the filter housing so that any metal particles are caught for inspection.

We ran about 50ish hours with the triple stackers installed on the mains this summer and I was quite surprised. Usually after 15-20 hours I can feel the soot grit between my fingers when rubbing the oil from the dipstick. I can feel the oil now and it is still very slick, it is not gritty feeling like it used to be. It is still black, but perhaps not as black as it normally is, if that makes sense?

 

[rustybucket]

https://www.dieselequipmentinc.com/p...iABEgK5lvD_BwE


I see a bracket..... Am I supposed to see a head? Thanks.

That is the head, it is integral with the bracket. The filter just screws on the bottom of that. The in/out ports are on each side.

 

[rustybucket]

Rusty, don't just replace the tips of the injectors, it's another $100 per but do the barrels and plungers as well. I have had them do a couple (m15) at a time as they become weak. Maybe mine costs more but they were $175/ea You should be good to go for several years unlike reliajunk's

RPM won't return an injector to you if it isn't in perfect condition.

What kelpy said, after talking with RPM, and a few other people who have done business with them I am inclined to trust them. I told them to make them like new, and was told, yeah, uh that's what we do when we rebuild them lol. I have given them the go-ahead to replace any parts that are in need.

 

[kelpy]

They do good work there. If you take your injectors in and ask them to just change the tips, they will most likely just hand them back to you .

I have all 32 of mine done by them every two years.

 

[rustybucket]

They do good work there. If you take your injectors in and ask them to just change the tips, they will most likely just hand them back to you .

I have all 32 of mine done by them every two years.

Curious, How many hours approx do you put on them in 2 years? Do you think a 2 year rebuild schedule is the way to go? Or should it be on an hourly schedule?

 

[rustybucket]

Coolant filter heads came in, figured I'd post a couple pics as the online pics of these are lacking.

 

[racclarkson@gmail.com]

Thanks, simple enough. Show us where you tapped in when you get round to it.

 

[kelpy]

Curious, How many hours approx do you put on them in 2 years? Do you think a 2 year rebuild schedule is the way to go? Or should it be on an hourly schedule?

Summers in the Northeast and winters in South Florida and Bahamas. That works out to approx. 30,000 gallons of fuel over those two years so let's say about 1000 gallons through each injector. Maybe a bit more with extended Bahamas runs.

 

[rustybucket]

Summers in the Northeast and winters in South Florida and Bahamas. That works out to approx. 30,000 gallons of fuel over those two years so let's say about 1000 gallons through each injector. Maybe a bit more with extended Bahamas runs.

I would love to be posting those types of numbers!! Someday!!!

 

[davidwigler]

Thanks, simple enough. Show us where you tapped in when you get round to it.

Also send us a link to the filters you use with it. I’m all in for this.

 

[rustybucket]

Also send us a link to the filters you use with it. I’m all in for this.

The coolant filter I use in all my other stuff is napa 4070. According to the specs of that filter head the napa 4070 should fit it but I have not tested yet. Will report back when I do.

 

[rustybucket]

Got 2 coolant filters installed on the main engines. Was easy enough. I tied into an existing/empty plug after the water pump and returned to the top of the tank. I mounted the filters forward of the engines on the floor support cross members.

Filter mounting location, very easy access when in the ER.

This is the supply line. I did NOT drain the coolant to add this fitting. I had a crimped/zip tied short length of hose affixed to it. I unscrewed the existing plug and screwed this one in as quickly as possible. I estimate I lost less than half a cup of coolant in both engines combined (WEAR EYE PROTECTION if you do this, gravity is def against you and the coolant wanted to spray more than I had expected.

Here is the return location. I had to use heat on every single plug I removed, hence the burned paint around them. Amazing how a little heat makes them so easy to remove.

No pics of the filters attached but NAPA 4070 did indeed fit these filter heads.

Did not run the engines any to test for leaks (still waiting on a few tuneup parts), will update with progress when I do. Also, I plan on running these filters for approx 100hrs and then cutting them open. Will post pics here when I do.

 

[rustybucket]

Finished the tuneup procedure and fired the engines. I can verify that coolant is making it's way through the new coolant filters!

Tuneup procedure was followed step-by-step via the manual and almost everything went off without a hitch. During the last steps of running the rack, I missed a step of pulling cotter pins from the fuel rods at the correct time. So I basically had to run the rack twice, once incorrectly, and the second time correctly.

I kinda got the feeling halfway through the second engine that i was not doing something right, so I came up and re-read the manual on running the rack and realized what I had done. One positive thing that came from it was that I became very good at setting the rack by feel by the time I was done.

One trick I got off youtube was to use a long set of vice grips. Clamped to the rack they allow you to visually see/feel even the most minute movements of the rack. That tip was not in the manual but was a great help.

The engines fired right up and were purring like kittens! I ran them at the dock at multiple rpms and WOT and everything sounded/looked great. Seatrial scheduled for Saturday!! Will have a diesel mechanic joining us on the seatrial so will have someone knowledgeable with detroits to check over my work and help look for any warning signs.

Can't wait to spool the 'ol gals up and see what she's got now! Diver hitting the bottom and running gear this week so we will be able to get some good numbers!

 

[davidwigler]

Great thread. Thanks!

 

[rustybucket]

Well, left the dock around 2 Saturday afternoon for a short shakedown trip. Overall engines ran great, good even temps on all cylinders. Full fuel aft, full water, about 1/8 tank fwd fuel. Overall I would say we were loaded about average, definitely not light, def not heavy.

Top speed was 25knts into the wind at WOT 2150. So we are still 200 rpms off where we need to be, and it felt like the boat was lugging. With a little prop work we should easily pickup those rpms and probably some more top speed as well. @2150rpm we were making 25knts, @1950rpms we were making 21knts, @1850rpms we were making 18knts

We are getting a little oil smoke on starboard engine, we are thinking maybe stuck ring, which should free up when we run her hard, or it could be blower seal. Really wish that blower seal was easier to inspect. These engines have been idled a lot lately and really need to stretch their legs for an extended period of time.

We got to really test out the newest version of Yacht Brain I've been working on for a few years now. Not to get too technical but it takes digital sensor data from the engines (currently only temps) and broadcasts them via wifi on the boats wifi network. So any device connected to the boat's wifi can access the data by entering an ip address in their browser, so iphone, ipad, computer, smart tv...etc. We had the engine temps running on the salon tv, an ipad on the bridge and an ipad in the engine room.

Here are the gauges shown on an ipad

Here they are on the tv